10. Pathology and Oncology MCQs

A 15-year-old boy presents with severe, nocturnal diaphyseal tibial pain that is dramatically relieved by ibuprofen. Radiographs show a small radiolucent nidus surrounded by dense reactive sclerosis. What is the molecular mechanism responsible for this classic pain pattern?

A 40-year-old male is incidentally found to have a cartilaginous lesion in the proximal humerus on a chest radiograph. Differentiating a benign enchondroma from a low-grade (Grade 1) chondrosarcoma can be exceptionally challenging. Which of the following is the most reliable clinical or radiographic indicator supporting a diagnosis of low-grade chondrosarcoma?

A 25-year-old male presents with persistent pain and swelling in his distal femur. Radiographs show a lytic lesion with cortical destruction and periosteal reaction. Further imaging (MRI, CT chest/abdomen) suggests a primary bone tumor. A biopsy is planned. Which of the following principles is most critical to adhere to during the biopsy procedure to avoid compromising future limb salvage surgery?

A 16-year-old male presents with deep knee pain and a mixed lytic/sclerotic lesion in the distal femur metaphysis with Codman's triangle. Core needle biopsy confirms high-grade intramedullary osteosarcoma. Staging is negative for metastasis. What is the standard treatment protocol?

A 12-year-old girl presents with fever, elevated ESR, and a diaphyseal lytic lesion of the fibula with "onion-skin" periosteal reaction. Cytogenetic analysis is most likely to show which of the following translocations?

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

A 12-year-old boy presents with a painful mass in the diaphysis of his left femur. Radiographs show a permeative, moth-eaten lytic lesion with an "onion-skin" periosteal reaction. Cytogenetics reveals a t(11;22) translocation. Which fusion protein is diagnostic for this condition?

A 16-year-old male presents with distal thigh pain and a palpable mass. Biopsy confirms high-grade, non-metastatic osteosarcoma of the distal femur. What is the standard treatment protocol for this patient?

A 15-year-old boy presents with a destructive diaphyseal lesion in his femur with a periosteal "onion skin" reaction. Biopsy reveals uniform small round blue cells. Cytogenetic analysis confirms a t(11;22) chromosomal translocation. Which specific fusion protein is the primary driver of this malignancy?

A 15-year-old boy presents with a painful mass in the diaphysis of his femur. Radiographs show a permeative, moth-eaten lesion with an 'onion-skin' periosteal reaction. Core biopsy is performed. Which of the following chromosomal translocations is most strongly associated with this lesion?

A 68-year-old man presents with severe back pain. Radiographs demonstrate multiple punched-out lytic lesions in the vertebral bodies and skull. Laboratory tests reveal hypercalcemia and anemia. Which of the following is the most appropriate next step to confirm the diagnosis of this condition?

A 20-year-old man presents with a 6-month history of a dull, aching thigh pain that is significantly worse at night and dramatically relieved by taking ibuprofen. Radiographs demonstrate a diaphyseal cortical thickening with a small radiolucent nidus. The relief of pain by NSAIDs in this condition is due to the inhibition of which molecule highly produced by the nidus?

A 25-year-old male presents with multiple cartilaginous tumors of the hands and long bones, as well as several bluish, soft-tissue masses on his extremities. Radiographs demonstrate multiple enchondromas. What genetic mutation is most strongly associated with this patient's underlying syndrome?

A 28-year-old female undergoes a biopsy for a slowly enlarging, calcified soft-tissue mass situated adjacent to the knee joint. Histology demonstrates a biphasic pattern of spindle cells and epithelial cells. Cytogenetic analysis confirms a t(X;18)(p11;q11) translocation. What is the most likely diagnosis?

A 45-year-old male presents with a painful, lytic lesion in the proximal humeral epiphysis. Biopsy reveals cells with abundant clear cytoplasm, distinct borders, and centrally located nuclei scattered among regions of hyaline cartilage. What is the most appropriate definitive management for this lesion?

A 22-year-old female presents with persistent back pain that frequently awakens her at night and is only partially relieved by NSAIDs. Imaging shows a 2.5 cm expansile, lytic lesion in the posterior elements of L3 with scattered calcifications and surrounding sclerosis. Which of the following is the most likely diagnosis?

A 12-year-old boy presents with a painful, swollen thigh. Radiographs show a permeative diaphyseal lesion with a periosteal 'onion-skin' reaction. Biopsy reveals small, round blue cells that are heavily positive for CD99. Which of the following chromosomal translocations is most characteristic of this tumor?

A 65-year-old male presents with severe back pain. Radiographs show multiple punched-out lytic lesions in the skull and a compression fracture at L2. Laboratory workup reveals hypercalcemia and anemia. What is the most likely diagnosis?

A 19-year-old male complains of severe, unrelenting right thigh pain that is distinctly worse at night and dramatically relieved by NSAIDs. Radiographs show a small radiolucent nidus surrounded by dense sclerotic bone in the proximal femur. Which of the following substances is produced in high amounts by the cells within the nidus?

A 28-year-old female presents with a slowly enlarging, deep soft tissue mass near her knee joint. Biopsy reveals a biphasic tumor with both epithelial and spindle cell components. Cytogenetic analysis shows a t(X;18)(p11;q11) translocation. What is the diagnosis?