10. Pathology and Oncology MCQs

A 19-year-old male complains of a dull, aching pain in his left thigh that has been worsening over the past 6 months. The pain is characteristically worse at night and is dramatically relieved by ibuprofen. Radiographs reveal a small radiolucent nidus surrounded by dense sclerotic bone in the proximal femoral diaphysis. What is the most appropriate initial management?

A 14-year-old boy presents with a painful, swollen mass over his mid-tibial shaft. Radiographs show a permeative, destructive diaphyseal lesion with an 'onion-skin' periosteal reaction. Biopsy reveals small round blue cells. Which chromosomal translocation is most characteristic of this tumor?

A 32-year-old woman presents with knee pain. Radiographs reveal an eccentric, lytic lesion in the distal femoral epiphysis extending to the subchondral bone, with a 'soap bubble' appearance. Biopsy shows multinucleated giant cells in a background of mononuclear stromal cells. What is the most likely diagnosis?

A 16-year-old male complains of severe right thigh pain that is worse at night and dramatically relieved by ibuprofen. Radiographs show a 7 mm radiolucent nidus surrounded by dense reactive sclerosis in the proximal femoral diaphysis. What is the most appropriate initial definitive management if medical therapy fails or is not tolerated?

A 16-year-old boy complains of severe, aching pain in his right thigh that is worse at night and dramatically relieved by ibuprofen. CT scan reveals a 1 cm radiolucent nidus surrounded by dense reactive sclerosis in the proximal femoral diaphysis. What is the primary biochemical mediator responsible for the characteristic pain pattern in this lesion?

A 19-year-old male complains of severe, aching pain in his right thigh that is worse at night and dramatically relieved by ibuprofen. Radiographs show a small radiolucent nidus surrounded by dense reactive cortical sclerosis in the proximal femoral diaphysis. The dramatic pain relief from NSAIDs is primarily due to the high concentration of which substance within the nidus?

A 19-year-old male presents with severe nocturnal thigh pain that is dramatically relieved by NSAIDs. Imaging reveals a 1 cm radiolucent nidus surrounded by dense reactive sclerosis in the proximal femoral diaphysis. What is the primary mechanism by which NSAIDs relieve pain in this specific pathology?

A 25-year-old female presents with a painless mass behind her knee. Radiographs reveal a densely ossified, lobulated mass arising from the posterior cortex of the distal femur without medullary involvement. Biopsy confirms a low-grade spindle cell stroma with well-formed woven bone. Amplification of which of the following genes is most characteristic of this lesion?

A 14-year-old boy presents with a painful scoliosis. Radiographs reveal a right-thoracic scoliotic curve. Advanced imaging shows a 1 cm radiolucent nidus with surrounding sclerosis in the T8 vertebra. Which of the following best describes the most likely location of the lesion and its relationship to the scoliotic curve?

A 9-year-old boy presents with a diaphyseal permeative lesion of the femur and periosteal "onion-skin" reaction. Histopathology reveals sheets of small, uniform round blue cells. Cytogenetic analysis is most likely to show which of the following chromosomal translocations?

A 12-year-old boy presents with a painful, swollen thigh. Radiographs demonstrate a permeative diaphyseal lesion with a periosteal 'onion-skin' reaction. A core biopsy confirms a small round blue cell tumor. Which of the following cytogenetic abnormalities is most characteristically associated with this diagnosis?

A 15-year-old girl is diagnosed with conventional high-grade osteosarcoma of the distal femur. She completes neoadjuvant chemotherapy, undergoes wide surgical resection, and the pathology reveals 95% tumor necrosis. What is the most significant prognostic implication of this histologic finding?

A 16-year-old boy presents with knee pain. Radiographs reveal a well-circumscribed lytic lesion in the distal femoral epiphysis with central calcifications. Histology shows mononuclear cells, osteoclast-like giant cells, and 'chicken-wire' calcification. What is the most appropriate initial treatment?

A 9-year-old girl presents with a limp, precocious puberty, and large irregular cafe-au-lait spots on her torso. Radiographs show a 'ground-glass' expansile lesion in her proximal femur with a 'shepherd's crook' deformity. What is the underlying pathophysiology of her bony lesions?

A 25-year-old male presents with a slowly enlarging, painful mass near the knee joint, but entirely extra-articular. MRI shows a soft tissue mass with focal calcifications. Biopsy shows a biphasic pattern of epithelial and spindle cells. Which specific genetic translocation confirms this diagnosis?

A 12-year-old boy presents with progressive, severe mid-thigh pain and swelling. Radiographs reveal a poorly marginated, permeative lytic lesion in the femoral diaphysis with an 'onion-skin' periosteal reaction. Biopsy demonstrates uniform small round blue cells that stain strongly positive for CD99. Which of the following chromosomal translocations is most characteristic of this diagnosis?

A 15-year-old boy presents with chronic right knee pain. Radiographs reveal a well-circumscribed, eccentrically located lytic lesion in the proximal tibial epiphysis with stippled calcifications. Histological examination of the curetted lesion shows mononuclear cells with grooved nuclei and areas of 'chicken-wire' pericellular calcification. What is the most likely diagnosis?

A 16-year-old male complains of nocturnal anterior thigh pain that is completely relieved by ibuprofen. Imaging shows a 1 cm radiolucent nidus with intense surrounding reactive sclerosis in the medial femoral diaphysis. What is the preferred minimally invasive definitive treatment?

A 14-year-old girl is evaluated for right shoulder pain. Radiographs show an expansile, eccentric, lucent lesion in the proximal humeral metaphysis. MRI demonstrates multiple internal fluid-fluid levels. Biopsy confirms blood-filled cystic spaces without an endothelial lining. Which genetic translocation is highly characteristic of this primary lesion?

A 14-year-old boy presents with a painful mass in his left mid-thigh. Radiographs show a destructive diaphyseal lesion with an "onion-skin" periosteal reaction. Biopsy reveals sheets of small, round, blue cells. Which of the following cytogenetic abnormalities is most characteristically associated with this condition?