Menu

10. Pathology and Oncology MCQs

Practice Set 197 of 351

This practice set contains high-yield board review questions covering key concepts in 10. Pathology and Oncology. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 3921

Topic: 10. Pathology and Oncology

A 16-year-old male with a suspected osteosarcoma of the distal femur undergoes an open biopsy. During the procedure, the surgeon inadvertently incises through the suspected tumor mass. According to the general 'tumor surgery principles,' which of the following describes the most significant immediate consequence of this technical error?

. Increased risk of pulmonary embolism due to tissue manipulation.
. Compromised accuracy of histological diagnosis due to tissue fragmentation.
. Elevated risk of local recurrence and potential need for wider resection margins.
. Delay in initiating neoadjuvant chemotherapy protocols.
. Increased risk of immediate pathological fracture.

Correct Answer & Explanation

. Elevated risk of local recurrence and potential need for wider resection margins.

Explanation

The 'not cutting through the tumor' principle is paramount in musculoskeletal oncology. Inadvertently incising through a sarcoma significantly increases the risk of tumor cell spillage and local recurrence. This technical error can 'seed' the wound or surrounding tissues, potentially requiring a wider, more radical resection or even amputation to achieve clear margins, thereby worsening the prognosis for local control. This directly violates the 'unsectional principle' and the 'prevention of tumor cell shedding and hematogenous metastasis during surgery' from the general medical principles. While accuracy of diagnosis might be slightly affected if the representative sample is compromised, the primary and most concerning consequence in terms of oncologic outcome is the increased risk of local recurrence.

Question 3922

Topic: 10. Pathology and Oncology

A 50-year-old male with a recent history of gastric cancer presents with bilateral ovarian masses. While typically outside the orthopedic domain, the provided general medical content specifically defines a metastatic tumor type relevant to this scenario. Which of the following diagnoses aligns with the general medical description?

. Ovarian leiomyosarcoma.
. Ovarian teratoma.
. Krukenberg tumor.
. Metastatic colon adenocarcinoma.
. Ovarian fibroma.

Correct Answer & Explanation

. Krukenberg tumor.

Explanation

The provided general medical content explicitly defines 'Krukenberg tumor' as: 'metastatic mucinous adenocarcinoma in the ovaries, usually from gastric primary.' This scenario precisely matches the description: a patient with gastric cancer developing bilateral ovarian masses. While it's a general medical concept, the question directly references the provided content, making Krukenberg tumor the correct answer.

Question 3923

Topic: 10. Pathology and Oncology

A 60-year-old male with a long history of heavy smoking and alcohol use presents with new onset of left hip pain, worse with weight-bearing. Radiographs show a lytic lesion in the proximal femur with cortical destruction. His past medical history includes lung cancer. According to general tumor surgery principles and orthopedic oncology evaluation, which of the following is the most appropriate initial diagnostic and management step?

. Perform an immediate open biopsy of the lesion to establish diagnosis.
. Initiate palliative radiation therapy to the hip to control pain.
. Order a CT scan of the chest, abdomen, and pelvis to assess for metastatic disease and primary source.
. Prescribe bisphosphonates to strengthen the bone and prevent pathological fracture.
. Perform prophylactic internal fixation to prevent imminent pathological fracture.

Correct Answer & Explanation

. Order a CT scan of the chest, abdomen, and pelvis to assess for metastatic disease and primary source.

Explanation

Given the patient's history of lung cancer and the new lytic lesion in the femur, metastatic disease is highly suspected. Themost appropriate initial stepis to stage the patient comprehensively to assess the extent of disease and identify the primary source (if not already known or to assess for further metastases). A CT scan of the chest, abdomen, and pelvis is essential for this purpose. This is a critical aspect of 'tumor surgery principles' where thorough staging precedes definitive local treatment. An open biopsy is usually performedafterstaging if the diagnosis is uncertain or to guide specific treatment. Radiation, bisphosphonates, or prophylactic fixation are treatment modalities that would follow diagnosis and staging, guided by the patient's overall prognosis and risk of fracture.

Question 3924

Topic: 10. Pathology and Oncology

A 60-year-old male with a history of prostate cancer, now with intractable back pain and bilateral leg weakness, is found to have a metastatic lesion compressing the thoracic spinal cord. He is neurologically intact below the lesion but has significant pain. Which of the following is the most appropriate initial management for this orthopedic oncology emergency?

. Immediate surgical decompression and stabilization.
. Initiation of high-dose corticosteroids.
. Palliative radiation therapy.
. Chemotherapy targeting the prostate cancer.
. Bracing and physical therapy.

Correct Answer & Explanation

. Initiation of high-dose corticosteroids.

Explanation

Acute spinal cord compression from metastatic disease is an orthopedic oncology emergency. Themost appropriate initial managementis the immediate initiation of high-dose corticosteroids (e.g., dexamethasone) to reduce peritumoral edema, which can rapidly improve neurological function and alleviate pain while further diagnostic workup and definitive treatment planning occur. While surgical decompression and radiation therapy are definitive treatments, corticosteroids provide rapid neuroprotection. Chemotherapy is systemic and not an immediate solution for acute cord compression. Bracing and PT are supportive, not primary for acute compression.

Question 3925

Topic: 10. Pathology and Oncology

A 70-year-old female with advanced primary bone lymphoma of the proximal femur requires surgical intervention. According to general 'tumor surgery principles,' which of the following statements regarding the role of biopsy is most accurate?

. An excisional biopsy is preferred to obtain a large tissue sample and ensure clear margins.
. Biopsy should be performed through the definitive surgical incision whenever possible.
. Biopsy is contraindicated if chemotherapy is planned as a primary treatment.
. Frozen section analysis during biopsy is sufficient for definitive diagnosis.
. Biopsy should be avoided in weight-bearing bones to prevent pathological fracture.

Correct Answer & Explanation

. Biopsy should be performed through the definitive surgical incision whenever possible.

Explanation

For bone tumors, the biopsy tract is considered contaminated with tumor cells and must be resected en bloc with the definitive specimen to avoid local recurrence. Therefore, the biopsy incision should be carefully planned and ideally placed in line with the planned definitive surgical incision, so the entire biopsy tract can be excised. This aligns with the 'tumor surgery principles' of preventing tumor cell shedding and local recurrence. An excisional biopsy is inappropriate for suspected malignancies. Biopsy is essential for diagnosis regardless of treatment plan. Frozen section provides preliminary information, but definitive diagnosis requires permanent sections. Biopsy is often necessary in weight-bearing bones, and risk of fracture is managed with post-biopsy precautions.

Question 3926

Topic: 10. Pathology and Oncology

A 30-year-old female presents with a new onset, rapidly growing mass in her proximal tibia. Biopsy confirms a high-grade osteosarcoma. According to the 'tumor surgery principles,' which of the following statements regarding the initial surgical plan is most aligned with current oncologic practice?

. Immediate wide excision of the tumor to prevent metastatic spread.
. Neoadjuvant chemotherapy followed by limb-sparing wide resection.
. Amputation as the primary treatment to ensure complete tumor removal.
. Intralesional excision to preserve as much bone as possible.
. Radiation therapy as the sole definitive treatment.

Correct Answer & Explanation

. Neoadjuvant chemotherapy followed by limb-sparing wide resection.

Explanation

For high-grade osteosarcomas, the standard of care involves neoadjuvant (preoperative) chemotherapy to downstage the tumor, treat micrometastases, and assess tumor response, followed by limb-sparing wide resection with clear margins. This approach balances oncologic control with functional preservation, aligning with the core tumor surgery principles of complete tumor removal while considering systemic disease. Immediate wide excision without neoadjuvant therapy can miss micrometastases and has a higher risk of local recurrence. Amputation is a salvage option. Intralesional excision is inadequate for high-grade sarcomas. Radiation is rarely curative for osteosarcoma alone.

Question 3927

Topic: 10. Pathology and Oncology

Which of the following describes the fundamental principle of 'unsectional principle' in tumor surgery, as outlined in the provided general medical content, when applied to musculoskeletal oncology?

. Avoid cutting into the tumor tissue during surgical resection.
. Perform a biopsy without removing the entire lesion.
. Excise the tumor and surrounding normal tissue with wide margins.
. Prioritize limb salvage over amputation in all cases.
. Perform neoadjuvant therapy before any surgical intervention.

Correct Answer & Explanation

. Avoid cutting into the tumor tissue during surgical resection.

Explanation

The 'unsectional principle' (or 'not cutting principle') in tumor surgery, as described, dictates that 'the tumor tissue should not be cut directly during surgery, but should be dissected from the periphery to the center.' This means avoiding any direct incision into the tumor mass itself to prevent tumor cell spillage and local recurrence. While excising with wide margins is the goal of definitive resection, the unsectional principle specifically refers to avoiding direct incision into the tumor during the dissection phase. Biopsy is typically incisional or core needle. Limb salvage and neoadjuvant therapy are broader concepts in oncologic management.

Question 3928

Topic: 10. Pathology and Oncology

A 60-year-old patient with an unresectable chordoma of the sacrum is experiencing severe, intractable pain. The general 'tumor surgery principles' emphasize avoiding cutting the tumor, but in cases of palliation, what is a primary goal of any intervention?

. To achieve complete tumor eradication at the microscopic level.
. To prevent all future metastatic spread.
. To preserve patient mobility at all costs.
. To improve quality of life by alleviating pain and maintaining function.
. To maximize life expectancy regardless of functional outcome.

Correct Answer & Explanation

. To improve quality of life by alleviating pain and maintaining function.

Explanation

While the fundamental tumor surgery principles aim for curative resection with negative margins, in the context of an unresectable tumor like a chordoma of the sacrum causing intractable pain, the primary goal of any intervention shifts topalliation. This means focusing on improving the patient's quality of life by alleviating pain and maintaining function (e.g., through debulking, stabilization, or radiation therapy). Complete eradication is not feasible in an unresectable tumor. Preventing all metastases is unrealistic. Maximizing life expectancy at the expense of quality of life may not be the patient's goal.

Question 3929

Topic: 10. Pathology and Oncology

What is the most common primary malignant bone tumor in children and young adults?

. Chondrosarcoma.
. Ewing sarcoma.
. Osteosarcoma.
. Multiple myeloma.
. Fibrosarcoma.

Correct Answer & Explanation

. Osteosarcoma.

Explanation

Osteosarcoma is the most common primary malignant bone tumor in children and young adults (typically second decade of life). It is characterized by the production of osteoid by malignant cells. Ewing sarcoma is the second most common. Chondrosarcoma and fibrosarcoma are generally less common, and multiple myeloma is a malignancy of plasma cells affecting older adults, not a primary bone tumor in children.

Question 3930

Topic: 10. Pathology and Oncology

What is the primary characteristic that distinguishes osteosarcoma from Ewing sarcoma on histopathology?

. Presence of small round blue cells.
. Production of osteoid by malignant cells.
. Formation of cartilage matrix.
. Presence of multinucleated giant cells.
. Spindle cell morphology.

Correct Answer & Explanation

. Production of osteoid by malignant cells.

Explanation

The defining characteristic of osteosarcoma is the production of osteoid (immature bone matrix) by malignant tumor cells. Ewing sarcoma is characterized by small, round, blue cells (similar to lymphoma or neuroblastoma) and often associated with the EWS-FLI1 translocation. Chondrosarcoma produces a cartilaginous matrix. Multinucleated giant cells are seen in giant cell tumors. Spindle cell morphology is less specific and seen in various soft tissue sarcomas and some bone tumors.

Question 3931

Topic: 10. Pathology and Oncology

A 16-year-old male presents with worsening nocturnal pain in his right femur, which is relieved by aspirin. Radiographs show a small radiolucent nidus surrounded by sclerotic bone. What is the most likely diagnosis?

. Osteosarcoma.
. Ewing sarcoma.
. Osteoid osteoma.
. Chondroblastoma.
. Aneurysmal bone cyst.

Correct Answer & Explanation

. Osteoid osteoma.

Explanation

The classic presentation of an osteoid osteoma is nocturnal pain that is characteristically relieved by NSAIDs (like aspirin), along with radiographic findings of a small radiolucent nidus surrounded by dense reactive sclerosis. This is a benign bone tumor. Osteosarcoma and Ewing sarcoma are malignant and would not typically respond so dramatically to aspirin. Chondroblastoma is an epiphyseal lesion. An aneurysmal bone cyst is expansile and lytic.

Question 3932

Topic: 10. Pathology and Oncology

Which of the following clinical findings is least typical for a patient presenting with an early, uncomplicated Richter hernia?

. Localized tenderness and a palpable mass at the hernia site
. Significant abdominal distention
. Pain out of proportion to physical findings
. Mild nausea without projectile vomiting
. Ability to pass flatus and stools

Correct Answer & Explanation

. Significant abdominal distention

Explanation

Significant abdominal distention is least typical for an early, uncomplicated Richter hernia because, by definition, only a portion of the bowel wall is entrapped, meaning the bowel lumen is usually not completely obstructed. Patients often present with localized tenderness, a palpable mass (which may be subtle), and pain disproportionate to the seemingly benign findings. They may experience mild nausea but often do not have projectile vomiting and can typically pass flatus and stools, distinguishing it from a complete bowel obstruction. Abdominal distention would suggest a more advanced stage with paralytic ileus secondary to peritonitis or development of a complete obstruction, which is less common initially.

Question 3933

Topic: 10. Pathology and Oncology

An 82-year-old bed-bound patient in a long-term care facility develops a new onset of severe right groin pain, fever, and leukocytosis. A small, firm, exquisitely tender mass is noted in the femoral region. Despite the lack of overt GI symptoms, a Richter hernia is suspected. Why is prompt surgical consultation critical, especially in this demographic?

. Elderly patients often tolerate prolonged periods of bowel ischemia well.
. The risk of spontaneous reduction is higher in bed-bound patients.
. Atypical presentations and delayed diagnosis in the elderly significantly increase morbidity and mortality from strangulation and sepsis.
. The use of multiple medications in the elderly complicates surgical repair.
. It is likely a benign lipoma and does not require urgent attention.

Correct Answer & Explanation

. Atypical presentations and delayed diagnosis in the elderly significantly increase morbidity and mortality from strangulation and sepsis.

Explanation

Prompt surgical consultation is critical because atypical presentations and delayed diagnosis in the elderly significantly increase morbidity and mortality from strangulation and sepsis. Elderly and frail patients often have blunted pain responses, vague symptoms, and a higher threshold for presenting with classic signs of acute abdomen. This can lead to a considerable delay in diagnosis of a Richter hernia, where rapid progression to strangulation and perforation is common. Consequently, they often present with advanced disease and sepsis, making outcomes much worse. Elderly patients do not tolerate ischemia well, spontaneous reduction is less likely with strangulation, and while polypharmacy can add complexity, it's not the primary reason for urgency related to the hernia itself. A benign lipoma would not cause fever, leukocytosis, and exquisite tenderness.

Question 3934

Topic: 10. Pathology and Oncology

Which long-term complication is most likely if a Richter hernia is misdiagnosed as an orthopedic groin strain and allowed to progress without surgical intervention?

. Development of chronic regional pain syndrome in the lower extremity.
. Irreversible bowel damage leading to short bowel syndrome, peritonitis, and death.
. Recurrent episodes of benign groin swelling.
. Development of hypertrophic osteoarthropathy.
. Progressive muscle weakness in the affected limb.

Correct Answer & Explanation

. Irreversible bowel damage leading to short bowel syndrome, peritonitis, and death.

Explanation

If a Richter hernia is misdiagnosed and allowed to progress, the most likely and catastrophic long-term complication is irreversible bowel damage leading to short bowel syndrome, peritonitis, and death. The inherent risk of strangulation and perforation with a Richter hernia means that prolonged delay in surgical intervention will result in extensive bowel necrosis, requiring massive resection. This can lead to short bowel syndrome (a severe malabsorption disorder) or, if perforation occurs, widespread peritonitis and sepsis, which is often fatal. All other options are less likely or not directly life-threatening consequences of untreated strangulated bowel.

Question 3935

Topic: 10. Pathology and Oncology

Which of the following conditions is most accurately diagnosed with a bone scan (technetium-99m methylene diphosphonate)?

. Stress fracture
. Osteosarcoma
. Disc herniation
. Soft tissue tumor
. Gout

Correct Answer & Explanation

. Stress fracture

Explanation

A bone scan (technetium-99m methylene diphosphonate) is highly sensitive for detecting areas of increased bone turnover, making it particularly useful for diagnosing stress fractures, which involve micro-trauma and increased osteoblastic activity. While it can detect osteosarcoma (as it's metabolically active bone), MRI is superior for characterizing bone tumors. Disc herniation and soft tissue tumors are not directly evaluated by bone scans. Gout is a joint inflammation, not a primary bone pathology best seen on a bone scan.

Question 3936

Topic: 10. Pathology and Oncology

What is the most common primary malignant bone tumor in children and young adults?

. Chondrosarcoma
. Ewing's sarcoma
. Multiple myeloma
. Osteosarcoma
. Fibrosarcoma

Correct Answer & Explanation

. Osteosarcoma

Explanation

Osteosarcoma is the most common primary malignant bone tumor in children and young adults (typically 10-30 years old), often affecting the metaphysis of long bones (e.g., distal femur, proximal tibia, proximal humerus). Ewing's sarcoma is the second most common, often affecting diaphyseal regions. Chondrosarcoma is more common in older adults. Multiple myeloma is a malignant proliferation of plasma cells, primarily affecting older adults, and is the most common primary bone malignancy overall. Fibrosarcoma is rare.

Question 3937

Topic: 10. Pathology and Oncology

What is the most common site for osteochondroma?

. Diaphysis of long bones
. Epiphysis of long bones
. Metaphysis of long bones
. Flat bones (e.g., pelvis, scapula)
. Vertebrae

Correct Answer & Explanation

. Metaphysis of long bones

Explanation

Osteochondroma is the most common benign bone tumor and typically arises from the metaphysis of long bones, especially around the knee (distal femur, proximal tibia) or proximal humerus. It grows away from the joint. It is characterized by a cartilage cap and continuity of the medullary canal with the underlying bone.

Question 3938

Topic: 10. Pathology and Oncology

What is the most characteristic radiographic finding in osteoid osteoma?

. Sunburst pattern
. Onion-skinning appearance
. Codman's triangle
. Small lucent nidus surrounded by dense sclerotic bone
. Ground-glass matrix

Correct Answer & Explanation

. Small lucent nidus surrounded by dense sclerotic bone

Explanation

Osteoid osteoma is a benign bone tumor characterized radiographically by a small, radiolucent nidus (typically less than 1.5 cm) surrounded by a zone of dense, reactive sclerotic bone. This appearance, especially with an identifiable nidus, is pathognomonic. Sunburst pattern, onion-skinning, and Codman's triangle are associated with malignant bone tumors (e.g., osteosarcoma, Ewing's sarcoma). Ground-glass matrix is seen in fibrous dysplasia.

Question 3939

Topic: 10. Pathology and Oncology

A 55-year-old male with a history of prostate cancer develops a blastic lesion in his thoracic spine causing cord compression. Which of the following is the most appropriate initial treatment strategy for his spinal cord compression, assuming good functional status otherwise?

. Systemic chemotherapy
. External beam radiation therapy
. Surgical decompression and stabilization
. Bisphosphonates and observation
. Radiofrequency ablation

Correct Answer & Explanation

. Surgical decompression and stabilization

Explanation

For metastatic spinal cord compression, especially with neurological compromise (even early), surgical decompression and stabilization is often the most appropriate and rapid initial treatment, particularly for patients with good functional status and reasonable life expectancy. It provides immediate relief of compression and allows for stabilization of the spine, preventing further neurological deterioration. While radiation therapy is crucial, it often follows surgery or is used alone in patients who are not surgical candidates or have radiosensitive tumors without significant instability. Systemic chemotherapy addresses the underlying cancer but is usually not fast enough to relieve acute cord compression. Bisphosphonates are for bone strengthening and pain, not acute compression. RFA is for local tumor control, not broad decompression.

Question 3940

Topic: 10. Pathology and Oncology
Regarding chondrosarcoma, which of the following statements about its staging and prognosis is most accurate?
. High-grade chondrosarcomas (G3) typically respond well to neoadjuvant chemotherapy.
. The T-stage for appendicular chondrosarcoma is solely based on tumor size in the 8th edition UICC.
. Enneking surgical staging is more commonly used than UICC for central chondrosarcomas.
. The primary prognostic factor for chondrosarcoma is the presence of skip lesions.
. Malignant transformation of an osteochondroma is generally considered a G1 chondrosarcoma.

Correct Answer & Explanation

. The T-stage for appendicular chondrosarcoma is solely based on tumor size in the 8th edition UICC.

Explanation

For bone sarcomas, including chondrosarcoma, the 8th edition UICC T-stage is primarily based on tumor size (T1 ≤ 8cm, T2 > 8cm) or the presence of skip lesions (T3). Unlike other bone sarcomas, chondrosarcomas are generally considered chemo- and radio-resistant, so neoadjuvant chemotherapy is not a standard effective treatment for high-grade lesions. Enneking staging is a surgical staging system, important for surgical planning, but UICC is the primary prognostic staging system. While skip lesions (T3) are a factor in T-staging, the histological grade (G) is generally considered the most significant prognostic factor for chondrosarcoma, directly correlating with metastatic potential. Malignant transformation of an osteochondroma typically results in a secondary peripheral chondrosarcoma, often low-grade (G1 or G2), not universally G1 and not a distinct type of primary chondrosarcoma within the staging system.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page