Menu

10. Pathology and Oncology MCQs

Practice Set 96 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 1901

Topic: 10. Pathology and Oncology
A 55-year-old man presents with an incidental finding of a proximal humeral lesion. Radiographs show 'pop-corn' calcifications and endosteal scalloping involving greater than two-thirds of the cortical thickness. Biopsy confirms a Grade II chondrosarcoma. What is the most appropriate definitive management?
. Intralesional curettage with bone grafting
. Extended intralesional curettage with argon beam coagulation
. Wide surgical resection
. Neoadjuvant chemotherapy followed by wide resection
. Primary radiation therapy

Correct Answer & Explanation

. Wide surgical resection

Explanation

Grade II and III chondrosarcomas exhibit aggressive local behavior and metastatic potential, requiring wide surgical resection. Unlike osteosarcoma or Ewing sarcoma, chondrosarcomas are generally resistant to chemotherapy and radiation.

Question 1902

Topic: 10. Pathology and Oncology

A 14-year-old boy presents with a diaphyseal femur lesion showing an 'onion-skin' periosteal reaction. Cytogenetic testing reveals a t(11;22) chromosomal translocation. What is the resulting fusion gene critical for the pathogenesis of this tumor?

. SYT-SSX1
. TLS-CHOP
. PAX3-FKHR
. EWS-FLI1
. COL1A1-PDGFB

Correct Answer & Explanation

. EWS-FLI1

Explanation

The clinical picture describes Ewing sarcoma, which is classically associated with the t(11;22)(q24;q12) translocation. This chromosomal abnormality results in the EWS-FLI1 fusion gene, acting as an aberrant transcription factor.

Question 1903

Topic: Bone Tumors

A 20-year-old man presents with a 'shepherd's crook' deformity of his proximal femur. Radiographs display a ground-glass appearance. This skeletal pathology is associated with a somatic activating mutation in the GNAS1 gene. If accompanied by cafe-au-lait spots, what endocrine disorder is most classically associated?

. Primary hyperparathyroidism
. Precocious puberty
. Hypothyroidism
. Cushing's disease
. Diabetes insipidus

Correct Answer & Explanation

. Precocious puberty

Explanation

The patient has fibrous dysplasia. When polyostotic fibrous dysplasia occurs with cafe-au-lait spots and endocrine hyperfunction, it is known as McCune-Albright syndrome. The most common endocrine abnormality in this syndrome is precocious puberty.

Question 1904

Topic: 10. Pathology and Oncology

A 15-year-old girl with distal femur osteosarcoma undergoes neoadjuvant chemotherapy followed by wide resection. Which of the following histologic findings from the resected specimen most accurately predicts her long-term survival?

. Mitotic rate of the tumor cells
. Presence of skip lesions in the medullary canal
. Greater than 90% tumor necrosis
. Negative surgical margins > 2 cm
. Absence of lymphovascular invasion

Correct Answer & Explanation

. Greater than 90% tumor necrosis

Explanation

The histologic percentage of tumor necrosis following neoadjuvant chemotherapy is the most significant prognostic factor for survival in osteosarcoma. Greater than 90% necrosis is considered a good response and correlates with improved long-term survival.

Question 1905

Topic: 10. Pathology and Oncology

A 60-year-old man presents with a destructive lesion in the proximal humerus. Biopsy confirms metastatic clear cell renal carcinoma. Prophylactic internal fixation is planned. What is the most appropriate step immediately prior to surgery?

. Initiation of systemic chemotherapy
. Administration of denosumab
. Pre-operative angiographic embolization
. Local radiation therapy
. Bone marrow aspiration

Correct Answer & Explanation

. Pre-operative angiographic embolization

Explanation

Metastatic renal cell carcinoma and thyroid carcinoma are notoriously hypervascular tumors. Pre-operative angiographic embolization within 24-48 hours of surgery is highly recommended to minimize catastrophic intraoperative blood loss.

Question 1906

Topic: 10. Pathology and Oncology

A 25-year-old female presents with a large sacral mass. Biopsy confirms Giant Cell Tumor of bone. Because wide surgical resection would result in severe neurological morbidity, medical therapy is indicated. Which of the following is the most appropriate primary medical treatment?

. Imatinib
. Denosumab
. Methotrexate
. Zoledronic acid
. Doxorubicin

Correct Answer & Explanation

. Denosumab

Explanation

Denosumab is a monoclonal antibody against RANKL. It is highly effective in treating Giant Cell Tumor of bone by inhibiting the osteoclast-like giant cells, leading to tumor consolidation and calcification, which can facilitate surgery or serve as definitive therapy for unresectable lesions.

Question 1907

Topic: 10. Pathology and Oncology

A 10-year-old boy is diagnosed with Ewing sarcoma of the femoral diaphysis. Which chromosomal translocation is classically pathognomonic for this tumor?

. t(11;22)
. t(X;18)
. t(9;22)
. t(12;16)
. t(2;13)

Correct Answer & Explanation

. t(11;22)

Explanation

Ewing sarcoma is classically associated with the t(11;22)(q24;q12) translocation. This results in the EWS-FLI1 fusion protein, which acts as an oncogenic transcription factor.

Question 1908

Topic: 10. Pathology and Oncology

A 45-year-old man has a progressively enlarging, painful mass in his right ilium. Biopsy reveals atypical chondrocytes in a myxoid stroma with a characteristic popcorn-like calcification pattern. What is the primary treatment modality for this disease?

. Neoadjuvant chemotherapy
. Definitive radiation therapy
. Wide surgical resection
. Radiofrequency ablation
. Hormonal therapy

Correct Answer & Explanation

. Wide surgical resection

Explanation

This patient has a chondrosarcoma. Chondrosarcomas are generally resistant to both chemotherapy and radiation therapy; therefore, wide surgical excision is the primary and most effective treatment for intermediate to high-grade lesions.

Question 1909

Topic: 10. Pathology and Oncology

A 14-year-old boy presents with a distal femur osteosarcoma and undergoes neoadjuvant chemotherapy prior to surgical resection. What histologic finding on the final resection specimen is the most important prognostic factor for overall survival?

. High percentage of chondroid matrix
. Tumor necrosis greater than 90%
. Presence of skip metastases
. Negative surgical margins
. Lack of vascular invasion

Correct Answer & Explanation

. Tumor necrosis greater than 90%

Explanation

The degree of tumor necrosis following neoadjuvant chemotherapy is the most significant prognostic indicator for overall survival in osteosarcoma. Greater than 90% necrosis indicates a good response to chemotherapy and correlates with improved long-term survival.

Question 1910

Topic: 10. Pathology and Oncology

A 65-year-old man with metastatic renal cell carcinoma presents with mechanical back pain and an isolated L3 vertebral body lesion without neurologic deficit. The Spinal Instability Neoplastic Score (SINS) is 14. What is the most appropriate management?

. External beam radiation therapy alone
. Bisphosphonate therapy and bracing
. Stereotactic radiosurgery alone
. Preoperative embolization followed by surgical stabilization
. Chemotherapy and observation

Correct Answer & Explanation

. Preoperative embolization followed by surgical stabilization

Explanation

A SINS score of 13 or greater indicates spinal instability, warranting surgical stabilization regardless of neurologic status. Because renal cell carcinoma metastases are highly vascular, preoperative embolization is strongly recommended to minimize intraoperative hemorrhage.

Question 1911

Topic: 10. Pathology and Oncology

A 10-year-old girl presents with pain and swelling in her mid-diaphyseal femur. Radiographs demonstrate a permeative destructive lesion with an "onion-skin" periosteal reaction. Biopsy confirms Ewing sarcoma. Which of the following genetic translocations is most commonly associated with this tumor?

. t(11;22)(q24;q12)
. t(X;18)(p11;q11)
. t(12;16)(q13;p11)
. t(2;13)(q35;q14)
. t(9;22)(q34;q11)

Correct Answer & Explanation

. t(11;22)(q24;q12)

Explanation

Ewing sarcoma is classically driven by a fusion of the EWSR1 gene on chromosome 22 with the FLI1 gene on chromosome 11. This t(11;22)(q24;q12) translocation is found in approximately 85% of cases.

Question 1912

Topic: 10. Pathology and Oncology

A 55-year-old male presents with progressive sacral pain and bowel/bladder dysfunction. MRI reveals a large, lobulated, destructive mass in the sacrum (S2-S4) with a hyperintense signal on T2-weighted images. Histopathology from a CT-guided biopsy shows physaliferous cells in a myxoid background. What is the most appropriate surgical treatment aiming for long-term disease-free survival?

. Intralesional curettage and radiation therapy
. En bloc wide resection
. Systemic chemotherapy followed by piecemeal resection
. Palliative decompression only
. Radiofrequency ablation

Correct Answer & Explanation

. En bloc wide resection

Explanation

The presence of physaliferous cells is pathognomonic for a chordoma, a low-grade, locally aggressive malignant primary bone tumor arising from notochordal remnants. Chordomas are largely resistant to conventional chemotherapy and standard radiation. The gold standard treatment aiming for cure or maximal local control is en bloc wide surgical resection with negative margins.

Question 1913

Topic: 10. Pathology and Oncology

A 60-year-old male with a history of renal cell carcinoma presents with progressive paraparesis and a sensory level at T10. MRI reveals a metastatic lesion at T9 with severe spinal cord compression. His estimated life expectancy is 12 months. Which of the following is the most appropriate management strategy?

. High-dose corticosteroids and observation
. Conventional fractionated external beam radiation therapy
. Surgical decompression and stabilization followed by stereotactic radiosurgery
. Chemotherapy tailored to renal cell carcinoma
. Percutaneous vertebroplasty

Correct Answer & Explanation

. Surgical decompression and stabilization followed by stereotactic radiosurgery

Explanation

Renal cell carcinoma is a radioresistant tumor. In a patient with mechanical instability or epidural spinal cord compression from a radioresistant metastasis and a life expectancy >6 months, surgical decompression (separation surgery) followed by stereotactic radiosurgery (SRS) is the gold standard.

Question 1914

Topic: 10. Pathology and Oncology

A 60-year-old female with metastatic renal cell carcinoma presents with mechanical back pain and an isolated L2 vertebral body metastasis. Neurological exam is intact, and MRI shows no epidural spinal cord compression. However, CT reveals bilateral pedicle destruction and 60% loss of vertebral body height. According to the NOMS framework, what is the most appropriate primary treatment strategy?

. Conventional external beam radiation alone
. Stereotactic body radiation therapy (SBRT) alone
. Surgical stabilization followed by SBRT
. Systemic chemotherapy alone
. Observation

Correct Answer & Explanation

. Surgical stabilization followed by SBRT

Explanation

The NOMS framework assesses Neurologic, Oncologic, Mechanical, and Systemic factors. Bilateral pedicle destruction and significant height loss indicate severe mechanical instability, which requires surgical stabilization prior to radiation therapy (SBRT is preferred here for radioresistant renal cell tumors).

Question 1915

Topic: 10. Pathology and Oncology

A 30-year-old construction worker sustained a high-pressure injection injury to his right index finger with an industrial paint thinner 2 hours ago. The entry wound is 2 mm at the distal palmar crease. He has mild swelling but no severe pain. What is the most appropriate next step in management?

. Administer broad-spectrum antibiotics, tetanus prophylaxis, and discharge with close follow-up.
. Admit for intravenous antibiotics, elevation, and serial examinations.
. Perform a digital block and bedside incision and drainage in the emergency department.
. Immediate surgical exploration and widespread debridement in the operating room.
. Administer local corticosteroid injection to minimize the severe inflammatory response.

Correct Answer & Explanation

. Immediate surgical exploration and widespread debridement in the operating room.

Explanation

High-pressure injection injuries to the hand are surgical emergencies, especially when involving organic solvents like paint thinner, which cause severe chemical necrosis and possess a high amputation rate (often >50%). Despite benign initial appearances, the material dissects proximally along tendon sheaths. Emergent wide surgical debridement in the operating room is mandatory. Digital blocks are contraindicated due to the risk of exacerbating compartment pressures.

Question 1916

Topic: 10. Pathology and Oncology

A 55-year-old male with a history of intravenous drug use presents with severe back pain, fever, and elevated ESR and CRP. MRI with gadolinium shows T1 hypointensity, T2 hyperintensity, and enhancement of the L3-L4 intervertebral disc and adjacent vertebral body endplates. Blood cultures are negative. What is the most appropriate next step to establish a microbiologic diagnosis before initiating long-term antibiotic therapy?

. Immediate broad-spectrum empirical intravenous antibiotics
. CT-guided percutaneous needle biopsy of the affected disc space
. Open anterior debridement and interbody fusion
. Posterior laminectomy and epidural exploration
. Fluoroscopy-guided lumbar puncture for CSF analysis

Correct Answer & Explanation

. CT-guided percutaneous needle biopsy of the affected disc space

Explanation

In cases of suspected pyogenic vertebral osteomyelitis/discitis where blood cultures are negative and the patient is neurologically stable, a CT-guided percutaneous needle biopsy is the gold standard next step to identify the causative organism. Empirical antibiotics should be withheld until tissue cultures are obtained to ensure directed therapy, unless the patient is septic or neurologically compromised.

Question 1917

Topic: 10. Pathology and Oncology
A 40-year-old man has a painless mass around his left ankle. He notes minimal growth over the past year. An MRI scan is shown in Figure 73a, and biopsy specimens are shown in Figures 73b and 73c. What is the most likely diagnosis?
. Epithelioid sarcoma
. Clear cell sarcoma
. Pigmented villonodular synovitis
. Malignant fibrous histiocytoma
. Synovial sarcoma

Correct Answer & Explanation

. Synovial sarcoma

Explanation

The biopsy specimen is a low-power view of a soft-tissue sarcoma with a biphasic pattern of epithelial cells and fibrous spindle cells that are typical of a synovial sarcoma. A deep, painless soft-tissue mass greater than 5 cm in size is suspicious for a sarcoma. The imaging in this patient is indeterminate and the patient requires a biopsy for an accurate diagnosis. The biopsy reveals a tumor with a biphasic appearance consistent with a synovial sarcoma. These tumors are slow growing, occur primarily in the lower extremities, and are found in a younger demographic population compared to malignant fibrous histiocytoma and liposarcoma. They can occur in a biphasic pattern with clumps of epithelial cells and fibrous spindle cells or in a monophasic pattern. Synovial sarcomas stain positively for keratin. Keratin is positive in nearly all biphasic types and in many tumors of the monophasic fibrous type. Sixty percent of these tumors are found in the lower extremity. The area around the knee is the most common location, followed by the ankle and foot.

Question 1918

Topic: 10. Pathology and Oncology
A 30-year-old woman has pain in her right hand. The radiograph, CT scan, and biopsy specimen are seen in Figures 38a through 38c. What is the most likely diagnosis?
. Enchondroma
. Giant cell tumor
. Metastatic carcinoma
. Degenerative cyst
. Eosinophilic granuloma

Correct Answer & Explanation

. Enchondroma

Explanation

DISCUSSION: An enchondroma is the most common primary tumor of the long bones of the hand. The lesion is usually asymptomatic and often is detected when there is a pathologic fracture.

Question 1919

Topic: 10. Pathology and Oncology

A 35-year-old male presents with chronic knee pain. Radiographs demonstrate a lytic lesion in the proximal tibial epiphysis with intralesional calcifications. Biopsy reveals cells with abundant clear cytoplasm, distinct borders, and chondroid matrix, alongside areas of woven bone. Which of the following is the most appropriate management?

. Intralesional curettage with adjuvant argon beam and cementing
. Wide surgical resection
. Pre-operative chemotherapy followed by wide resection
. Radiation therapy followed by curettage
. Observation with serial radiographs

Correct Answer & Explanation

. Wide surgical resection

Explanation

The clinical and histological presentation is characteristic of clear cell chondrosarcoma. Unlike conventional chondrosarcoma, it typically presents in the epiphysis of long bones and often in young to middle-aged adults. It is a low-grade malignant bone tumor. Standard treatment is wide surgical resection, as curettage carries an unacceptably high local recurrence rate. It is not highly responsive to chemotherapy or radiation.

Question 1920

Topic: 10. Pathology and Oncology

A 12-year-old boy is diagnosed with Ewing sarcoma of the femoral diaphysis. Following his initial regimen of neoadjuvant chemotherapy, what is the single most important prognostic factor for his long-term survival?

. Patient age at the time of diagnosis
. Tumor volume prior to the initiation of chemotherapy
. Percentage of tumor necrosis found in the definitive resection specimen
. Presence of the definitive t(11;22) chromosomal translocation
. Surgical margin width strictly greater than 2 cm

Correct Answer & Explanation

. Percentage of tumor necrosis found in the definitive resection specimen

Explanation

While tumor size, volume, and the presence of metastasis at diagnosis are significant prognostic factors, the percentage of tumor necrosis following neoadjuvant chemotherapy (histologic response) is one of the most powerful and reliable predictors of overall and disease-free survival in patients with localized Ewing sarcoma. Greater than 90% necrosis is generally considered a favorable histological response.

Test Yourself

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

On this Page