DEFINITION

Vascular tumors are diverse and often have a confusing nomenclature. Part of the confusion resides in the ambiguity of the term tumor, which literally means “growth” or “swelling” but usually connotes a proliferative process. Vascular tumors were often named based on clinically descriptive terms (eg, strawberry hemangioma) rather than underlying histopathology. Consequently, the term vascular tumor

has been applied to both nonproliferative and proliferative lesions.9 Similarly, the term hemangioma has been used to describe various vascular lesions that have different biologic behavior.14

Since 1996, the International Society for the Study of Vascular Anomalies (ISSVA) has adopted a standardized nomenclature to facilitate the classification, diagnosis, and treatment of vascular tumors.14

“Vascular anomalies” is now the widely accepted term for benign congenital vascular lesions that include both vascular tumors and vascular malformations.

The majority (90%) of vascular growths of the hand fall within this category (benign congenital lesions).

Vascular tumors, or hemangiomas, are true neoplasms characterized by endothelial proliferation. The most common vascular tumor is infantile hemangioma.

Vascular malformations are nonproliferative lesions that result from dysmorphogenesis. Examples of vascular malformations include capillary malformations, venous malformations, and congenital arteriovenous fistulas (AVFs). Many of these malformations have been historically mislabeled as hemangiomas (Table 1).

The remaining 10% of vascular lesions not included in the previously mentioned group include noncongenital vascular tumors, which may be benign (eg, glomus tumor) or malignant (eg, hemangioendothelioma, hemangiosarcomas, glomangiosarcoma, and malignant hemangiopericytoma), and traumatic or iatrogenic lesions, such as AVFs and pseudoaneurysms.

Table 1 Historical Terms for Vascular Anomalies

Tumors

Infantile hemangioma (strawberry hemangioma)
Lobular capillary hemangioma (pyogenic granuloma)
Kaposiform hemangioendothelioma

Vascular Anomalies Malformations

Arteriovenous malformation (arteriovenous hemangioma)
Venous malformation (cavernous hemangioma)

The incidence of congenital vascular tumors and malformations in the general population is about 2% to 6%.20

Most are discovered at birth, although some may not be evident until adulthood.

About 15% to 26% of vascular anomalies present in the extremities,24,37 most commonly the hand and forearm.20

Vascular anomalies are fourth in frequency among upper extremity tumors, after ganglions, giant cell tumors, and inclusion cysts.

Vascular anomalies are categorized into tumors and malformations. Note the historical terms in parentheses, which in many cases are misnomers.

Capillary malformation (port-wine stain, capillary hemangioma)
Lymphatic malformation (lymphangioma)

ANATOMY

Arteries in the hand terminate at either a capillary bed or a glomus body. The glomus is a specialized arteriovenous shunt that functions as a neuromyoarterial mechanoreceptor. It lies in the stratum reticularis of the skin, especially in the subungual region and distal pads of the digits. The glomus body acts as a thermoregulator and it regulates peripheral blood flow in the digits and possibly controls peripheral blood pressure. It contains the glomus cells surrounding the Sucquet-Hoyer canals, which are narrow vascular anastomotic channels.

PATHOGENESIS

Various theories for the pathogenesis of vascular tumors exist. Some implicate endothelial cells originating from disrupted placental tissue that becomes embedded in fetal soft tissue; others link hemangioma formation

to abnormal circulating hematopoetic stem cells.27 Various theories exist as to the pathogenesis of vascular malformations, but broadly speaking, they are thought to occur as a failure of differentiation or involution of common embryonic vascular channels.24

Acquired vascular tumors are usually due to trauma that induces pseudoaneurysms or fistulas.

NATURAL HISTORY

Vascular Tumors

Infantile Hemangiomas

Also referred to as strawberry hemangiomas or capillary hemangiomas, infantile hemangiomas are the most common benign vascular tumor in infancy, with a reported incidence of 1% to 4% among Caucasian infants.37

Thirty percent of hemangiomas are visible at birth, but this increases to 70% to 90% before the infant is 4 weeks old.37

Hemangiomas typically are reddish lesions that become raised during the growth phase (FIG 1).

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FIG 1 • Infantile hemangioma of the second web space of the right hand. Note the typical red color and raised appearance. During the proliferative phase, these lesions may ulcerate.

These lesions classically progress through a proliferative phase marked by rapid growth, an involution phase

marked by gradual replacement with fibrofatty tissue, and resolution.34,36 As a general rule, the overall rate of involution among affected individuals occurs at 10% per year; thus, 50% of hemangiomas will involute by the

time the child is 5 years old and 70% will involute by the age of 7 years.37 Exceptions do occur; a subset of infantile hemangiomas (rapidly involuting congenital hemangiomas or RICH) are characterized by a lack of a proliferative phase and complete resolution by 12 to 18 months of age, whereas another subset of

hemangiomas (noninvoluting congenital hemangiomas or NICH) do not spontaneously involute.37 Because these hemangiomas also tend to be fully formed at birth, they are usually categorized separately as congenital

hemangiomas to distinguish them from infantile hemangiomas.27

Histologically, hemangiomas are characterized by endothelial proliferation and consist of plump endothelial cells with high turnover rates.20 They may be further classified by other histologic features and location (superficial, subcutaneous, or intramuscular).24 Thirty percent of upper extremity hemangiomas will ulcerate, which becomes acute or chronic paronychia, especially in children who suck their fingers.33 Other complications include bleeding, infection, pain, and permanent skin changes after involution.37

If the hemangioma is associated with thrombocytopenia and consumptive coagulopathy, it is termed

Kasabach-Merritt syndrome, which is unrelated to the size of the hemangioma and is associated with a 30%

to 40% mortality.13 Multiple treatment modalities exist, including surgical extirpation, ablation, and/or compression, none of which are consistently efficacious.

Sclerosing hemangiomas contain a perivascular thickening of the lymphatic cells. These lesions have fibrous rather than a hematogenous origin and represent 10% of all hemangiomas.24

Although observation is the rule for infantile hemangiomas, occasionally, complications such as ulceration, slow regression, impairment of function, or psychosocial factors prompt intervention. Common agents include intralesional or oral corticosteroids and vincristine. Propranolol, a nonselective beta-adrenergic agonist, has in recent years been shown to be efficacious and safe in the treatment of hemangiomas. Although no clear protocols for its use in hemangiomas of the upper extremity exist, propranolol is a valuable therapeutic option that has changed the paradigm for hemangioma management and may be considered as an alternative to

observation in problematic lesions.17

Kaposiform Hemangioendothelioma

Kaposiform hemangioendotheliomas have been historically included with capillary hemangiomas.14 Although capillary hemangiomas, or infantile hemangiomas, have been reported to represent about 57% of

subcutaneous hemangiomas, the incidence of true kaposiform hemangioendotheliomas is exceedingly small.19

Histologically, these lesions are distinguished from infantile hemangiomas by their characteristic tightly packed “can-nonball nests” of endothelial cells within the dermis, sheets of spindle cells, and close resemblance to

Kaposi sarcoma.19

Clinically, these lesions do not spontaneously involute and the treatment modality with the most consistent results is vincristine alone or surgical resection.37

Lobular Capillary Hemangiomas

Lobular capillary hemangiomas, or pyogenic granulomas, make up 20% of the vascular tumors of the hand and may be a variant of a capillary hemangioma. They appear as a well-circumscribed lesion.

They develop rapidly and become pedunculated, friable outgrowths that are easily traumatized and bleed. In children, these lesions are more commonly found on the glabrous portion of the palm and digits as well as in the mouth and around the lips and face. In adults, they are more commonly found on the fingers and toes.

They may occur spontaneously but more frequently present as an overgrowth of granulation tissue in an area of previous penetrating trauma (FIG 2).7,24,31,36

Vascular Leiomyomas

Vascular leiomyomas are very rare tumors of the hand. They arise in the smooth muscle of the tunica media of veins in 50% of cases and are typically well encapsulated, small, round, firm, colorless, and curable (FIG 3).15

FIG 2 • A. Pyogenic granuloma of the left ring finger. The patient developed an open lesion of the cuticle that progressively swelled and then blistered over the nail bed. B. Pyogenic granuloma of the left index finger. Notice the granular, raised appearance.

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FIG 3 • A. Vascular leiomyoma of the right index finger. The patient presented after a 7-month history of having a trauma at work. She stated that the growth appeared 3 months later and had increased in size since then. B. Intraoperative photograph of the above vascular leiomyoma. It is a well-circumscribed lesion that is difficult to differentiate from an aneurysm except on pathology.

Vascular Malformations

Vascular malformations are uniformly present at birth but may not be visible until childhood, adolescence, or adulthood. Most appear by ages 2 to 5 years.36 They enlarge proportionately with the child unless they are stimulated by trauma, hormones, infection, or surgery.4 These lesions have an equal sex distribution.

Malformations generally have flat, slowly dividing endothelial cells.

Vascular malformations present with a mass or skin discoloration depending on the depth of the lesion. They enlarge shortly after birth and grow with the child.31

It is important to differentiate vascular malformations from hemangiomas because vascular malformations do not involute. Growth is due to progressive dilatation of the vessels and recurrence or regrowth after excision is

due to alteration in hemodynamics and rerouting of flow through previously quiescent aberrant channels (FIG 4).

Patients with vascular malformations will complain of the mass effect of the lesion, increased size with exercise, or pain due to thrombosis. Elevation of the extremity eases symptoms. These lesions may lead to nerve compression at the forearm and wrist and digital compression may be seen with localized

thrombosis.31,33

Vascular malformations consist of venous, capillary, arterial, and lymphatic malformations. Because up to 70% of vascular malformations are mixed, classification is not always straightforward. In the Hamburg classification, vascular malformations of the extremities are classified by the predominant vascular defect and by whether a

truncular or extratruncular form, depending on involvement of a major axial vessel.3

Vascular malformations are also classified as either low-flow or high-flow lesions based on their radiographic appearance and clinical characteristics. Before the routine use of magnetic resonance imaging (MRI) and Doppler ultrasound (US), angiography was used to estimate flow rates and shunt volume. Based on these findings, high-flow lesions were distinguished from low-flow lesions by the caliber and rate of opacification of feeding and draining vessels. The use of angiography has been augmented—and increasingly supplanted— by the development of Doppler US, nuclear scanning, and MRI, which have allowed more precise

measurement of flow velocities, shunt volumes, and soft tissue anatomy.18

Low-flow malformations have large channels without intervening parenchyma and often are associated with phleboliths. These lesions are more common than high-flow lesions, representing 90% of vascular

malformations. They consist mainly of venous, capillary, and lymphatic malformations.32

High-flow malformations usually have an arterial component and arteriovenous shunting. Marked enlargement and increased number of arteries, small vessels, and veins are consistent findings.5

High-flow malformations present early as a painless mass. They have a bimodal occurrence: 40% show up

at birth and another 34% after 10 years old.31 They do not contract with elevation. Later in childhood, they can become painful and lead to distal ischemia or even high-output heart failure if large and untreated.

They have been divided into three types:

Type A lesions have single or multiple AVFs, aneurysms, or ectasias involving the arterial side. They are localized to a specific anatomic region.32,36

Type B lesions consist of arteriovenous anomalies with microfistulas or macrofistulas that are localized to a single limb, hand, or digit. They have stable flow characteristics and provoke minimal to no distal symptoms. As with type A lesions, they remain localized to an anatomic region.32,36

Type C lesions enlarge slowly. They are diffuse, with microfistulas and macrofistulas involving all limb tissues. With increasing size, vascular steal occurs. They can cause distal ischemic pain, tachycardia, and congestive heart failure. Compartment syndrome, compression neuropathies, and ulceration secondary to ischemia or attempted surgical interventions can occur. The result can be unrelenting,

progressive pain, eventually leading to amputation.31,32 These lesions are notoriously difficult to treat.32

Venous Malformations

Historically termed cavernous hemangiomas (see Table 1), venous malformations represent the majority of vascular malformations and are also the most common vascular anomaly overall.31

Venous malformations are characterized histologically by thin-walled vessels and abnormally arranged smooth muscle cells that lead to ectatic changes over time, hence the term cavernous hemangioma.

Clinically, venous malformations present as bluish compressible nodules. Slow commensurate growth, compressibility,

and phleboliths are pathognomonic for venous malformations (FIG 5).20

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FIG 4 • Vascular malformation of the hand. Note the dilated vasculature. The growth of these lesions is due to progressive ectasia of the vessels and regrowth after excision is due to rerouting of flow through aberrant channels secondary to alterations in hemodynamics.

FIG 5 • Venous malformation of the ulnar side of the left hand. Notice the blue color and slightly raised appearance.

They can occur in isolation or with any number of syndromes, including blue rubber bleb nevus syndrome or

Klippel-Trenaunay syndrome (see section on Syndromes Related to Vascular Malformations of the Hand and Upper Extremity).37

They may be associated with limb or digit overgrowth.31

Capillary Malformations

Capillary malformations, as known as port-wine stains or nevus flammeus, are a common congenital vascular

malformation.37 They are dark red to purple and may have other associated vascular lesions. Over time, they become darker and acquire a cobblestone appearance.

Histologically, these lesions are characterized by a normal number of dilated capillaries and postcapillary venules in the upper dermis.

The treatment for these lesions is generally nonsurgical and consists of pulsed dye laser. Other modalities include intense pulsed light, photodynamic therapy, and angiogenesis inhibitors such as topical imiquimod and

rapamycin.37

Arteriovenous Malformations

Arteriovenous malformations have direct arteriovenous shunts without intervening capillaries and, like venous malformations, may be associated with a number of syndromes, including Parkes-Weber syndrome and Klippel-Trenaunay syndrome. These are more likely to be high flow and be complicated by ulceration and high-output failure as well as amputation (FIG 6).

As with venous malformations, arteriovenous malformations may be associated with limb or digit hypertrophy.31

Lymphatic and Mixed Malformations

Lymphatic malformations enlarge secondary to fluid accumulation, cellulitis, or inadequate drainage of

lymphatic channels.20 They can limit hand motion, and infections are common.31 They can also cause bone hypertrophy (FIG 7).

Mixed vascular malformations share the characteristics of their combination of vascular malformations.

Syndromes Related to Vascular Malformations of the Hand and Upper Extremity

Klippel-Trenaunay syndrome is characterized by port-wine stains, combined low-flow vascular malformations

(capillary, lymphatic, and venous), and limb enlargement due to hypertrophy of soft tissue and bone.37 Visceral malformations may occur as well.

FIG 6 • A. Arteriovenous malformation involving the entire upper extremity of a teenage boy. B. Angiography demonstrating the dense nest of blood vessels at the elbow. Note the enlarged feeding and draining vessels.

C. Surgical dissection of the forearm. This patient ultimately required an amputation at the shoulder secondary to high-output heart failure.

Parkes-Weber syndrome, like Klippel-Trenaunay syndrome, is also characterized by combined vascular malformations and skeletal hypertrophy of the affected limb. A distinguishing characteristic is the presence of

high-flow lesions and complex multiple AVFs.18

Both of these syndromes may have significant medical sequelae, including congestive heart failure, pulmonary embolism, venous thrombosis, bleeding, and cellulitis.

Proteus syndrome is a progressive condition characterized by widespread cutaneous and subcutaneous nevi, lipoma, and mixed venous malformations.18

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FIG 7 • Lymphatic malformation of the right hand.

Maffucci syndrome is characterized by multiple endochondromas, exostoses, and venous malformations.18 Blue rubber bleb nevus syndrome is characterized by multiple venous malformations of the skin. A distinguishing feature is the presence of gastrointestinal malformations that are at risk for bleeding.18

Acquired Lesions

Acquired lesions comprise both true and false aneurysms of vessels, glomus tumors, pyogenic granulomas, fistulas, and vascular leiomyomas.

True aneurysms contain all three layers of the vessel wall: intima, media, and adventitia. False or pseudoaneurysms do not contain all three layers of the vessel wall.

FIG 8 • A. Venous aneurysm of the palm. Again, a bluish tinge is noticeable over the lesion. B. Intraoperative view of a venous aneurysm. There is dilatation present at the vein. C. Ulnar digit artery false aneurysm. The patient sustained a traumatic injury at work and noted an increase in the size of the lesion over the ensuing 6 weeks. D. Hypothenar hammer syndrome. The patient was releasing a mechanical latch of a machine by using the heel of his hand, which caused a sharp pain. The patient presented with coolness of the ring fingertip and associated pain.

True Aneurysms

True aneurysms account for 6% of all tumors of the hand.24

True aneurysms, most notably hypothenar hammer syndrome, usually follow blunt trauma in the area of the vessel. The trauma may be a single event or repeated injury. The vessel dilates in response to injury to the arterial media, leading to fusiform vessel enlargement.

Aneurysms also occur secondary to disease processes such as arteriosclerosis, metabolic disorders, Kawasaki disease, Buerger disease, hemophilia, osteogenesis imperfecta tarda, granulomatous arteritis, and cystic adventitial disease (FIG 8).20

Pseudoaneurysms

Pseudoaneurysms account for most (83%) aneurysms of the hand and generally occur on the palmar surface of the hand.

They may be secondary to a puncture wound (such as from a knife or pencil) or complete rupture of the vessel

wall with continuity maintained by the surrounding soft tissues.20,24 They typically present with significant soft tissue swelling (FIG 9).

Pseudoaneurysms develop slowly over time and are usually not evident for weeks to months after the injury. A bruit may be noted on examination. Like true aneurysms, the most common vessel is in the ulnar artery.

Acquired Arteriovenous Fistulas

Acquired AVFs occur secondary to trauma or surgical intervention. AVFs consist of a communication between an artery and a vein that shunts away from the higher resistance capillary system.

Traumatic AVFs occur when there is penetrating injury to an artery and the adjacent vein, leading to a hematoma and

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shunting. This may occur secondary to injury with such objects as small knives or pencils, but it may also be due to venipuncture, arterial cannulation, or catheterization procedures. AVFs secondary to iatrogenic vascular injuries tend to occur slowly, whereas those that occur secondary to other trauma are usually rapid in onset. This may be secondary to the size of the puncture that occurs; iatrogenic injuries tend to be smaller

punctures than traumatic ones.33 Patients with intrinsic coagulation deficiencies are more vulnerable to this complication.

FIG 9 • A. Pseudoaneurysm of the radial artery due to injury, associated with significant soft tissue swelling.

B. Angiogram showing extravasation of blood from the proximal radial artery walled off by surrounding soft tissue.

Surgical AVFs are formed for dialysis access in patients with renal failure and can cause similar symptoms, including vascular steal (ischemia distal to the fistula secondary to shunting of blood), venous arterialization, and hand edema.

Glomus Tumors

Glomus tumors make up 8% of the vascular tumors of the hand and 1% to 4.5% of all hand tumors.24,34 They arise in the neuromyoarterial apparatus that was first described by Wood in 1812 and then again by Masson in 1924. These lesions have been found in the stomach, trachea, and retina but are most commonly found in the

digits. Glomus tumors are more consistent with a hamartoma than a true tumor.20 Sixty-five percent of these lesions are found in women 30 to 50 years old.

FIG 10 • A. Glomus tumor of the left ring finger, subungual region. The patient presented with minimal discoloration and sensitivity to heat and cold. B. Glomus tumor of the left thumb. The patient had more significant discoloration of the subungual region consistent with a glomus tumor. C. Although the patient had minimal discoloration with the nail plate on, the bluish hue becomes more discernible after the nail is removed.

Between 26% and 90% of solitary glomus, tumors are located in the subungual region.20 These lesions tend to be small—normally 5 mm and usually less than 1 cm. They are encapsulated and contain numerous small lumina when found as single tumors. Multiple tumors tend to be nonencapsulated, rarely subungual, with larger shaped vascular spaces.

Multiple glomus tumors tend to be asymptomatic and present earlier in life, whereas solitary tumors often go undiagnosed or misdiagnosed for years because the lesions are small and not palpable (FIG 10).21

The classic triad of pain, tenderness, and cold sensitivity is associated with glomus tumors. Lancinating pain is the most common symptom.28

Malignant Tumors

Malignant vascular tumors account for less than 1% of all vascular hand and forearm tumors.24 There are several types of malignant vascular tumors: hemangioendothelioma, glomangiosarcoma (malignant glomus tumors), angiosarcoma, Kaposi sarcoma, lymphangiosarcoma, and hemangiopericytoma.

Hemangioendotheliomas tend to arise adjacent to or within veins. They extend centrifugally from the vessel. They are slow-growing tumors, and tumors that show greater than one mitosis per high-power field on histology are more likely

to metastasize. Metastasis may occur locally to lymph nodes or distantly to the lungs, liver, or bone.36

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Glomangiosarcomas are extremely rare and were first described in 1972 by Lumley and Stansfield. They tend to be low-grade tumors that are locally invasive. They occur in adults aged 20 to 89 years. There are three categories of glomangiosarcoma: locally infiltrative glomus tumor (LIGT), which are identical to solitary glomus tumors except for the tendency toward infiltrating growth and recurrence after resection; glomangiosarcoma arising in a benign glomus tumor (GABG); and de novo glomangiosarcoma (GADN), which is a sarcoma with

round cells and features of the a benign glomus tumor.16,25,26

Angiosarcomas are rare and aggressive and metastasize early. They may occur after radiation therapy or long-term exposure to polyvinyl chloride. They are sometimes mistaken for hemangioendotheliomas on

histology. The prognosis is extremely poor for these tumors; the mean survival after diagnosis is 2.5 years.20,24,36

First described by Kaposi in 1872 in elderly men of Jewish and Mediterranean heritage, Kaposi sarcoma present as small, purple macules. They are a malignant degeneration of the reticuloendothelial system. These lesions tend to start on the hands or lower extremities, progress to the trunk, and coalesce into large papules. In this patient population, the disease has an indolent course and may be treatable with surgery and radiation.

Kaposi sarcoma has been closely associated with HIV/AIDS, and in this patient population, the disease is much more aggressive, with a larger number of lesions. In these patients, it is associated with human herpes virus 8.20,24,36

Lymphangiosarcoma is a rare cancer that occurs after long-standing lymphedema, as seen in some postmastectomy patients. These lesions metastasize rapidly.

Hemangiopericytoma is a diffuse proliferation of capillaries, encased in connective tissue, and surrounded by pericytes. They have no nerve elements and are generally painless. Patients tend to delay treatment secondary to lack of pain. They may present as a nonpigmented bleeding mole; an ulceration with prominent telangiectasia; or a dark blue, hemorrhagic swelling.

Histologically, they have sheets of spindle cells surrounding capillaries, regular oval nuclei without anaplasia, indistinct cytoplasmic borders, and a reticulin sheath surrounding each cell on silver stain.15,35

FIG 11 • A. Hemangiopericytoma of the right forearm. The patient presented with a large mass of the forearm that had been present for 46 years. B. Intraoperative view of hemangiopericytoma. The lesion was 9 × 6.6 × 5 cm and weighed 168 g.

Pathologists have described three histologic grades based on the previously mentioned criteria: benign, borderline malignant, and malignant. It has an unpredictable behavior and may metastasize years after excision; therefore, long-term (5 to 10 years) follow-up is recommended (FIG 11).

PATIENT HISTORY AND PHYSICAL FINDINGS

A complete history and physical examination of the patient is imperative.

It should be determined whether the lesion was present at birth or infancy or appeared later in adolescence or adulthood.

The history of rate of growth may help to differentiate between a hemangioma and an arteriovenous malformation in early childhood.

Hemangiomas

Hemangiomas will appear as a reddish lesion that becomes raised. Lesions of the axilla or interdigital region will be chronically macerated. Fingertip hemangiomas may present with findings similar to an acute or

chronic paronychial infection, especially in children who suck on their fingers.32 Vascular malformations

Low-flow malformations most commonly present as a mass or skin discoloration. If a capillary component is present, there may be a reddish stain of the skin. The presence of a compressive symptoms from the lesion consistent with a mass effect, distention, or pain with exercise would indicate a venous malformation.

Ulceration is uncommon in these lesions.

If there is a lymphatic component, patients may present with intralesional infections secondary to ruptured vesicles and maceration of large lesions.

They may also be found in association with syndromes such as Parkes-Weber, Klippel-Trenaunay, Proteus, and Mafucci (see section on Syndromes Related to Vascular Malformations of the Hand and

Upper Extremity).31,32 When multiple lesions are present, an associated syndrome should be considered.

High-flow malformations tend to be painless early on but then progress to be warm, painful masses with palpable thrills and bruits as the child grows.

Relief of the pain with elevation, increased pain with exercise, and increased warmth in the lesion may help to distinguish these from low-flow lesions.

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Presence of symptoms of congestive heart failure, which may occur as sequelae of an untreated high-flow malformation31

Any patient who is suspected of an arteriovenous malformation should be evaluated for other lesions, Nicoladoni sign (decrease in pulse rate with occlusion of the fistula), and any evidence of distal ischemia.20 Aneurysms and pyogenic granulomas

A history of trauma in the region, how long the lesion has been present, whether a pulsatile or bleeding mass is present is sought.

Glomus tumors

The classic triad of paroxysmal pain, pinpoint tenderness, and cold intolerance is typical of a glomus tumor. On physical examination, the physician should look for a bluish discoloration (found in 28% of patients) and a pulp nodule or nail deformity (found in 33% of patients).21

Duration of symptoms can assist in differentiating glomus tumors from other upper extremity tumors because most patients tend to have symptoms for more than 10 years.

A patient with multiple glomus tumors tend to be less symptomatic.

An Allen test should be performed.1

Methods for examining vascular lesions of the hand:

Inspect for blue spots, nail ridging, reddish, raised lesions, pulsatile masses, or traumatic injury, which helps to differentiate between malformations, aneurysms, pyogenic granulomas, and glomus tumors.

Using a stethoscope placed gently over the lesion, listen for bruits or thrills that are consistent with a fast-flow arteriovenous malformations.

If a pulsatile mass is felt, ascertain whether the lesion is compressible and tender.

Love pin test: To locate a glomus tumor, use the head of a pin or paper clip pressed gently against the tender area to localize the site of maximum discomfort. In subungual tumors, the pin is placed on the nail

plate at various locations to find the tumor.21

Hildreth test: The digit is exsanguinated by placing a tourniquet at its base or the hand is exsanguinated by elevating it and making a tight fist. The point of tenderness located by the Love pin test is then repeated: If the patient has diminished pain with this maneuver, then the test is considered positive for a glomus

tumor.11

IMAGING AND OTHER DIAGNOSTIC STUDIES

Plain radiographs of the digits and hands

Phleboliths (in 6%) and bony hypertrophy may be noted.20,24

There may be evidence of a soft tissue mass or signs of bone erosion or destruction of the cortical surface, which is seen in about 6% of patients with hemangiomas.24

Doppler ultrasonic flow detection is a noninvasive study that does not require the use of contrast.

It has been used to confirm high-flow anomalies and to help differentiate between hemangiomas and malformations.31 Doppler ultrasonography will show these lesions to be monophasic with low-flow velocity averaging 0.22 kHz.30

Computed tomography with contrast enhancement may show bony involvement of the tumor, especially in type A high-flow malformations.32

MRI/magnetic resonance angiography (MRA) can be used to evaluate the site, size, flow rate, and characteristics of the lesion as well as involvement of contiguous structures.32

It may be used to determine whether a malformation is low flow or high flow and can also distinguish between dense parenchymal lesions and malformations with large vascular channels.14

It can also be used to evaluate glomus tumors, which have a high signal intensity on T2-weighted spin-echo MRI or after gadolinium injection.21

MRI has a sensitivity of 90% and a specificity of 50% for glomus tumors, so that it cannot be used as the only diagnostic study for glomus tumors, especially if they are less than 2 to 3 mm in size.2

Hemangiomas will appear as well-circumscribed mass lesions that enhance with gadolinium and will have a high T1 signal secondary to infiltrative margins and fatty tissue overgrowth as well an extremely high,

heterogeneous T2 signal. A serpentine pattern in the mass may also be seen on MRI.36

MRA may be performed at the time of MRI to evaluate lesions in patients who are unable to undergo angiography secondary to renal problems or contrast allergies. It can be used to define the anatomic extent of lesions and their relationship with the surrounding tissue. It can be used to evaluate for both arterial and

venous tumors without contrast enhancement.8

Technetium 99m red blood cell perfusion and blood pool scintigraphy will show increased activity on early and late blood pool images with increased perfusion in hemangiomas and may be useful in their diagnosis.36 Angiography is the gold standard evaluation of certain tumors, including vascular malformations. No longer

routinely used for diagnosis of a lesion, it is used as an evaluation for operation or embolization.32 It may show

a cluster of anomalous arterial branches with multiple communications with venous trunks draining the site of involvement.22

Closed venous angiography uses contrast injected into the venous system distal to a proximal arterial tourniquet applied on the upper arm. Contrast is injected into the exsanguinated extremity distal to the tumor,

and radiographs are taken as the vascular tumor fills to get an accurate assessment of the anatomy.20 Arterial angiography is performed through a stick into the femoral artery with a catheter that is fed into the involved extremity. Dye is then injected and both the arterial and venous phases of circulation are evaluated. This can be used to evaluate the size of the tumor, locate the feeding vessels, and embolize feeding vessels before

operation (FIG 12).20

DIFFERENTIAL DIAGNOSIS

Foreign body Bacillary angiomatosis Pyogenic granuloma Glomus tumor Hemangioma

Arteriovenous or lymphatic malformation AVFs (traumatic, congenital, iatrogenic) Traumatic aneurysm (true or false)

Mycotic aneurysm (hematogenous or exogenous) Arteriosclerotic aneurysm

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FIG 12 • A. Angiogram of hypothenar hammer syndrome. The ulnar artery flow is absent and collaterals have formed to allow for flow in the palmar arch. This patient was relatively asymptomatic until a trauma to the hand. B. Angiogram of a second patient with hypothenar hammer syndrome. In this patient, there are no collaterals present, and he presented with coldness of the ulnar distribution digits.

Congenital aneurysm

Metabolic aneurysm (eg, osteogenesis imperfecta, granulomatous arteritis, Buerger disease) Vascular leiomyomas

Glomangiosarcoma Angiosarcoma Hemangioendothelioma Hemangiopericytoma Kaposi sarcoma Lymphangiosarcoma

NONOPERATIVE MANAGEMENT

Observation is the mainstay of management for hemangiomas. Up to 90% of these lesions will involute by the age of 9 years.37

Large venous or capillary malformations should be observed for limb growth disturbances and a possible underlying high-flow lesion.

Limb compression garments can be used to compress massive congenital AVFs that are inoperable, giant venous malformations, lymphatic malformations, or large hemangiomas in the arm and forearm.24,31 For larger lymphatic lesions, home compression pumps can be used to decrease edema at night.31

Antibiotic prophylaxis is indicated in patients who have recurrent infections in lymphatic malformations. The bacteria most commonly responsible for these infections is penicillin-sensitive beta-hemolytic streptococcus.31 If a patient with venous malformations or capillary-venolymphatic malformation has recurrent intralesional

thrombosis, then low-dose aspirin may be added to the compression garments for effective therapy.31

Local wound care and dressings may be required if ulcerations occur in the periungual regions or the central portions of large lesions during the involutional phase.31

Pulsed dye laser or argon laser may be used with some hemangiomas to treat the pigmented lesion without damaging the overlying skin, sweat glands, and hair follicles. Lasers of 585-nm wavelength work well on vascular lesions, such as hemangiomas, which are rich in hemoglobin. The laser heats the hemoglobin, causing coagulation of the vessels in the dermis. Scar formation ensues and replaces the damaged blood

vessels.24

Sclerotherapy with 1% sodium tetradecyl sulfate for small superficial lesions or 100% ethanol for large, deep saccular lesions may be used in treating venous malformations.

With the larger lesions, there is a possibility of skin ulceration, necrosis, inflammatory changes, and contracture due to the treatment and patients should be warned to watch for these sequelae.31

In arteriovenous malformations interventional radiology may be used for embolization of selectively catheterized vessels with polyvinyl alcohol foam or tissue adhesive. This may be done as a stand-alone treatment or in conjunction with surgery. In small lesions, embolization may completely occlude the malformation and destroy the lesion, eliminating the need for surgical resection. Several embolizations may be

necessary.20 In larger or more complex lesions, embolization is usually followed by surgical resection 24 to 48 hours later.

Complications of embolization include tissue loss, neurologic deficit, and enlargement of the malformation if the lesion is large and not excised promptly.12,22

Either intralesional or systemic steroids may be useful for the treatment of hemangiomas. A 6-week course may help to treat life-threatening or tissue-threatening lesions. This is also true for interferon alpha-2a or 2b. However, neither of these medications has been shown to have any effects on malformations, and the morbidity (neutropenia, elevation of liver enzymes, and spastic diparesis) of interferon must be considered

before its use.31,36

Radiation therapy was used in the past for sclerosis of hemangiomas; however, it leads to atrophic changes in the skin and subcutaneous tissue as well as arrest of skeletal growth.24

SURGICAL MANAGEMENT

Indications for surgery include pain, intralesional thrombi, episodic bleeding or ulceration, recurrent infection, or functional problems related to the size or weight of the extremity. It is important to consider whether the extremity will be functional after the proposed surgical treatment; in many cases, amputation may be a better

option.31

Lymphatic malformations have the added difficulties of beta-hemolytic streptococcal septicemia, skin maceration, and vesicular eruptions. This makes the planning of surgical

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resection complex. Complications occur in 25% of all procedures. The surgeon should be aware that tumor-

free tissues, such as grafts or flaps, may be necessary for coverage.31

Preoperative Planning

Radiographic studies should be reviewed carefully to plan resection of large or complex lesions.

An Allen test should be performed on the patient to evaluate for the patency of the superficial palmar arch and to see if the patient has an adequate ulnar artery.

If the Allen test is abnormal, reconstruction of the radial artery is necessary if it is to be resected.

Positioning

A proximal arm tourniquet is used, but the arm should not be exsanguinated with an Esmarch bandage to avoid the proximal spread or localized compression of the tumor. Exsanguination with the Esmarch bandage may also obscure the margins of hemangiomas and malformations.

Injections around the tumor should also be avoided to reduce the risk of local spread and compression of the mass, which could cause incomplete resection.

Approach

The technique chosen is based on the location of the lesion and the access necessary for excision.

Ligation of Feeding Vessel

For lesions that are small, with few feeder vessels, direct exploration and ligation of the feeding vessels can lead to involution of the lesion without significant tissue loss.

If tissue loss occurs, excision of the area and either primary closure, skin grafting, or flap reconstruction can be performed.

Staged Excision

Staged excision is useful for venous malformations, lymphatic malformations, combined malformations, and types A and B high-flow malformations, especially when large or involving multiple anatomic areas.32

For larger lesions, interventional radiology may be helpful in embolizing feeding vessels. This will decrease or limit the amount of open exposure necessary in the first stage.

In this approach, the extremity is not exsanguinated completely to facilitate identification of the vessels.

Several key principles must be adhered to when dealing with malformations of the upper extremity: (1) rigorous hemostasis with tourniquet control, (2) staged dissection within well-defined anatomic areas, (3) careful identification and preservation of all anatomic structures, (4) complete removal of well-localized lesions,

and (5) delay of next stage until after return of function and softening of scar tissue.32

When excising these lesions, all feeding and draining vessels must be ligated proximal and distal to the tumor. It is possible that ligation of these vessels may induce distal ischemia. The authors' preference is to temporarily occlude feeding and draining vessels with vascular clamps and assess distal perfusion. If distal ischemia is observed, the surgeon should be prepared to bypass the anatomic defect with autogenous vein grafts. Alternatively, the vessels in question may be selectively preserved, with the understanding that multiple staged procedures may be necessary and reexpansion of the tumor may occur.

If the tumor is adherent to the skin, that portion of tissue is excised as well and the area is covered with grafts or flaps.24

Amputation

Amputation is the treatment choice for highly aggressive malignancies such as hemangiosarcoma, lymphangiosarcoma, aggressive hemangioendothelioma, and massive arteriovenous malformations that have created a nonfunctional extremity.

This should be performed with a proximal tourniquet for operative hemostasis.

If the lesion is too proximal for a tourniquet, an internal vascular balloon can be used to occlude the feeding vessel or vessels.

Guillotine amputation is an option if infection is present; otherwise, closure should be performed at the time of amputation.

The most common error we have seen after amputation of a digit or hand is failure to obtain adequate, tension-free soft tissue coverage.

Wide local excision may be considered for less aggressive hemangioendothelioma, hemangiopericytomas, malformations, and hemangiomas that have not involuted.

TECHNIQUE

Transungual Excision

Transungual excision is an approach to subungual lesions, such as glomus tumors. Make small radial and ulnar corner incisions over the nail fold (TECH FIG 1A,B).

Half the nail is then elevated and folded over, allowing for visualization of the nail matrix (TECH FIG 1C).

The nail can be completely removed with a Freer elevator if necessary for access to the tumor (TECH FIG 1D).

Make a longitudinal incision with a no. 15 blade into the nail matrix, directly over the tumor, and excise the lesion circumferentially down to the phalanx (TECH FIG 1E,F).

Curette the bone before the nail bed is closed with 6-0 plain gut.

Replace the nail into the eponychial fold as a dressing for the nail bed and suture the corner incision closed (TECH FIG 1G).21,29

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TECH FIG 1 • A. Radial and/or ulnar incisions of the nail fold are drawn. If the lesion is proximal in the nail bed, one or both of these incisions may be necessary to access the lesion. B. The incisions are at oblique angles to the nail fold to avoid contracture of the area. C,D. The nail plate is elevated off the nail bed with a Freer elevator. Half the nail is elevated primarily (C), but the entire nail may be removed to allow for access to the lesion (D). Incision(s) are then extended, if necessary, to allow for visualization. E,F. A longitudinal incision is made in the nail bed to allow for removal of the lesion. The bone is curetted to remove any tumor, and the nail bed is then closed with 6-0 or 7-0 plain gut. G. The nail plate is then replaced as the dressing and the incision(s) are closed with 5-0 or 6-0 nylon or chromic.
Lateral Incision

This is an alternative to the transungual excision and allows exposure of the dorsal distal phalanx without violating the nail matrix. Because the view of the tumor is narrower, we do not recommend this

approach.21

If this approach is to be used, then a longitudinal midaxial incision slightly dorsal to the neurovascular bundle is used (TECH FIG 2A).

The incision is placed on the radial or ulnar surface of the digit, based on the location of the lesion.

Sharp dissection is carried out to the distal phalanx without manipulating the surrounding soft tissue. A small, sharp elevator is used to create a subperiosteal dorsal flap (TECH FIG 2B).

A small curette or elevator is used to excise the lesion.

The flap is replaced, and the incision is closed with interrupted or running nylon suture.29,34

TECH FIG 2 • A. A midlateral incision is drawn just dorsal to the midaxial line. The incision is carried sharply down to the bone, keeping the neurovascular bundle volar to the incision and dissection. B. A Freer

elevator is then used to create a subperiosteal flap to allow removal of the lesion.2,4,5,6,7,8,10,11,12,14,15,16,20,21,22,23,24,25,26,29,30,31,32,33,34,35,36
Epiphysiodesis

P.1303

Epiphysiodesis, destroying the growth plate by scraping or drilling, may help to diminish hypertrophy in patients whose digits have reached adult size.

Make a midaxial incision sharply, with dissection continued to the bone.

Retract the neurovascular bundle volarly to avoid injury (TECH FIG 3A).

TECH FIG 3 • A. A midlateral incision is made sharply and dissection continues to the level of the bone. The neurovascular bundle is retracted with the volar flap to ensure that it is not injured during dissection. The dorsal branches may be ligated or left intact, if it does not interfere with the exposure of the phalanx.

B. A drill is used to annihilate the growth plate of the phalanx to halt its growth. The incision is then closed with 5-0 or 6-0 nylon.

The dorsal branches may be transected if it is necessary to gain access to the dorsal aspect of the phalanx.

Use a burr to destroy the growth plate of the phalanx (TECH FIG 3B). Close the incision with 5-0 or 6-0 nylon.

PEARLS AND PITFALLS

Avoid overly aggressive

Have a tourniquet on the extremity before the incision for resection of lesions. arteriovenous malformations.

Make the family aware of the guarded prognosis for complete ▪ Exsanguination of an

removal of arteriovenous malformations and possibility of arteriovenous malformation may overgrowth or recurrence of the lesions. lead to incomplete excision.

Insist on multiple high-quality imaging studies to evaluate the ▪ For small lesions, imaging lesions. may not fully show the lesion.

Check patient for associated syndromic abnormalities.

POSTOPERATIVE CARE

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After excision of the lesion, most patients will require a conforming dressing and will be able to return to their normal activity within 1 to 6 weeks, depending on the size and location of the lesion.

Patients with partial resection of arteriovenous malformations may need to continue wearing compressive garments postoperatively when the dressings are removed.

If a skin graft or flaps is required, dressings and splints should be left in place to keep the patient from shearing the graft or pulling at the flap until the incisions are healed.

Graft bolsters or splints should be left in place for about 4 to 7 days to allow the graft to adhere.

For patients who require amputations, prosthetics may be helpful, depending on the patient and level of amputation. These are more readily available for patients who have below- or above-elbow amputations, although patients who have forequarter amputations may also be candidates for specialized prosthetics.

OUTCOMES

The prognosis of hemangiomas is not affected by race, gender, tumor site, size, or presence at birth.16 Attempts to excise arteriovenous malformations may lead to serious complications.

Complications are seen in about 22% of slow-flow lesions and 28% of fast-flow lesions. Wound dehiscence, seromas, and hematomas are noted early on. Partial skin loss and incision site infection are seen in the late postoperative period.

In fast-flow malformations, episodic bleeding and wound breakdown are more common.23

After resection of venous malformations and lymphatic malformations, persistent edema and swelling are frequent. Patients with type C arteriovenous malformations (see section on Vascular Malformations) more consistently require multiple operative procedures due to complications.

Disseminated intravascular coagulation has been reported in venous and arteriovenous malformations, and coagulation studies should be obtained before any intervention.

In the study by Mendel and Louis,22 13 of 17 lesions persisted after excision through extension or recurrence. Ten of these lesions were diffuse. Thus, two-fifths of lesions that are thought to be

localized are diffuse and will require more than one procedure for complete excision.

In view of the high recurrence rate after excision, excision should be considered in selected situations. Partial resection might be chosen to provide relief of symptoms but as a balance between aggressive resection and preservation of function.22

Patients who had wide local excision of venous malformations were found to have a 2% recurrence rate.20

It is generally accepted that primary tumor excision is the treatment of choice in all adults with venous malformations and children who have been observed for 1 year without regression of the lesion.

Glomus tumors recur in 15% to 24% of patients, with an average time before recurrence of 2.9 years.

Late presentation of recurrence is thought to be due to a new tumor near the site of excision. Patients who had incomplete excisions had recurrence of the tumor within weeks of surgery.

In patients who had transungual excisions, nail deformities were noted in 26% of patients.

The prognosis of hemangioendothelioma depends on the grade of the tumor. Patients with low-grade lesions have a good long-term survival rate, and those with aggressive tumors may not survive longer than 2 years.

Kaposi sarcoma in elderly non-HIV patients may be cured with wide local excision; however, the accepted treatment for these patients is chemoradiation and alpha-interferon therapy. The 5-year survival rate of these patients is only 19%. In patients with HIV/AIDS, the mortality rate of Kaposi sarcoma was 80% at 2

years, but this has improved with highly active antiretroviral therapy (HAART).24

For patients with hemangiosarcoma, early radical amputation is the treatment of choice. Palliative radiation has also been used. The average survival is 2.5 years, and the 5-year survival rate is less than 20%. One-third of patients with hemangiosarcoma have hemorrhage or coagulopathy, and 45% have

nodal metastases.24

Glomangiosarcomas are believed to be low-grade malignancies; however, more than 25% of reported

cases develop metastases.16 Wide local excision is the treatment of choice for these lesions, and close long-term follow-up is necessary.

COMPLICATIONS

High-output cardiac failure Consumptive coagulopathy Bacterial endocarditis Distal ischemia

Tissue loss Local infection

Compartment syndrome Arterial steal Hematoma

Seroma

Partial wound dehiscence

Cellulitis at the operative site Hypertrophic scarring

Joint contracture Neuromas

Reflex sympathetic dystrophy Pain

Extremity gangrene Vesicle formation Recurrence

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