10. Pathology and Oncology MCQs

A 22-year-old male presents with dull, aching thoracic back pain that is not significantly relieved by NSAIDs. CT imaging demonstrates a 3.5 cm expansile, lytic lesion in the posterior elements of T11 with a thin sclerotic rim. Histology reveals interlacing trabeculae of woven bone lined by prominent osteoblasts in a highly vascular stroma. What is the most likely diagnosis?

A 25-year-old male presents with a deep, slow-growing soft tissue mass in his foot. Biopsy reveals a biphasic tumor with both epithelial and spindle cell components. Which chromosomal translocation is most characteristic of this lesion?

A 15-year-old boy presents with progressive knee pain and a palpable mass in the distal femoral diaphysis. Radiographs demonstrate a permeative, destructive bone lesion with an "onion skin" periosteal reaction. Biopsy confirms small round blue cells. Which of the following cytogenetic abnormalities is most characteristic of this tumor?

A 19-year-old male presents with severe, progressive mid-tibial pain that is worse at night and dramatically relieved by over-the-counter ibuprofen. Radiographs demonstrate a diaphyseal cortical thickening with a small radiolucent nidus. What is the primary mechanism by which non-steroidal anti-inflammatory drugs (NSAIDs) relieve pain in this condition?

A 15-year-old male presents with persistent knee pain. Radiographs reveal a mixed lytic and sclerotic lesion in the distal femoral metaphysis with a 'sunburst' periosteal reaction. Biopsy confirms high-grade intramedullary osteosarcoma. What is the standard treatment protocol?

A 68-year-old male presents with severe back pain and generalized fatigue. Laboratory studies reveal hypercalcemia, anemia, and an elevated total protein with a monoclonal spike on serum protein electrophoresis (SPEP). Radiographs demonstrate multiple 'punched-out' lytic lesions in the skull and vertebral bodies. Which of the following is the most definitive diagnostic test for the underlying condition?

An 11-year-old boy presents with a painful mass in his diaphyseal femur. Biopsy reveals small round blue cells. Cytogenetic analysis is pending. Which of the following chromosomal translocations is most characteristic of this lesion?

A 24-year-old male complains of severe dull pain in his thoracic spine that is not reliably relieved by NSAIDs. CT scan shows a 2.5 cm radiolucent nidus with posterior element expansion. Histology shows interlacing trabeculae of woven bone lined by prominent osteoblasts. What is the most likely diagnosis?

A 72-year-old woman presents with severe back pain. Laboratory testing shows anemia, hypercalcemia, and renal insufficiency. Radiographs reveal multiple punched-out lytic lesions in her skull and pelvis. Which of the following laboratory findings is most specific for confirming her likely diagnosis?

A 35-year-old woman presents with knee pain. Radiographs reveal an eccentric, lytic, epiphyseal lesion in the proximal tibia that extends to the subchondral bone without a sclerotic margin. What is the most likely diagnosis?

A 16-year-old boy presents with severe right shin pain that is significantly worse at night and dramatically improves with oral ibuprofen. Radiographs show a thickened cortical area in the tibial diaphysis surrounding a central 5mm radiolucent nidus. Which of the following best describes the expected histological appearance of the central nidus?

A 15-year-old boy presents with severe thigh pain. Radiographs reveal a destructive, permeative diaphyseal lesion of the femur with a prominent 'onion-skin' periosteal reaction. Histological evaluation confirms a small round blue cell tumor. Which of the following chromosomal translocations is most strongly associated with this patient's diagnosis?

A 14-year-old boy presents with progressive knee pain. Plain radiographs reveal an aggressive, ill-defined metaphyseal radiolucent lesion in the distal femur with a 'sunburst' periosteal reaction and a Codman's triangle. A core needle biopsy is obtained. Which of the following histological descriptions is the hallmark finding for the most likely diagnosis?

A 14-year-old boy presents with progressive knee pain and a palpable distal femoral mass. Biopsy confirms high-grade conventional osteosarcoma. Which of the following underlying genetic mutations is most strongly associated with the pathogenesis of this tumor?

A 14-year-old boy presents with a destructive diaphyseal lesion of the femur with an associated periosteal "onion skin" reaction. Biopsy confirms Ewing sarcoma. Which of the following genetic translocations is most characteristic of this diagnosis?

A 15-year-old boy presents with severe, unrelenting mid-thigh pain. Radiographs reveal a permeative, destructive diaphyseal bone lesion in the femur with a prominent 'onion-skin' periosteal reaction. Biopsy demonstrates a population of small, round, blue cells. Which chromosomal translocation is most characteristically associated with this pathology?

An 8-year-old boy incidentally undergoes radiography of the humerus, revealing a centrally located, well-circumscribed, radiolucent lesion in the proximal metaphysis with a cortical fragment resting at the dependent aspect of the cyst ('fallen leaf' sign). If aspirated, what is the most likely composition of the fluid contained within this lesion?

A 15-year-old female presents with a distal femoral mass. MRI suggests an aggressive primary bone sarcoma. A biopsy is planned. Which of the following is an absolute principle of a musculoskeletal oncology biopsy?

A 14-year-old boy presents with a painful, swollen thigh. Radiographs show a permeative, 'moth-eaten' lesion in the femoral diaphysis with an 'onion-skin' periosteal reaction. Cytogenetic testing of the biopsy specimen is most likely to reveal which of the following chromosomal translocations?