Welcome to your Bone, Cartilage & Soft-Tissue Tumours Arena
1.
A uterine smooth-muscle tumour shows moderate cellularity but no significant atypia, no tumour-cell necrosis and very low mitotic activity. Which conclusion is most appropriate?
2.
A malignant smooth-muscle tumour enlarges rapidly and develops central areas of necrosis. Which mechanism most directly causes the necrosis?
3.
A 43-year-old woman presents with increasing abdominal fullness. Imaging reveals a large retroperitoneal fatty tumour. The mass is removed, but microscopic tumour is present at the surgical margin. Which outcome is the greatest concern?
4.
A child with a genitourinary rhabdomyosarcoma develops difficulty passing urine. Which tumour effect most directly explains this presentation?
5.
Two spindle-cell tumours are compared. Tumour X contains uniform fibroblasts in abundant collagen and repeatedly recurs locally. Tumour Y shows cytological atypia, increased mitoses and distant pulmonary deposits. Which diagnosis best describes Tumour Y?
6.
A deep soft-tissue tumour is composed of malignant spindle cells arranged in intersecting bundles that meet at sharp angles. The patient later develops pulmonary nodules. Which combination best describes the primary tumour?
7.
A giant-cell tumour is removed from the proximal tibia of a skeletally mature patient. The multinucleated cells are cytologically bland, but the lesion has destroyed the cortex. Which statement best explains this behaviour?
8.
A 24-year-old woman presents with pain and stiffness around the shoulder. Imaging identifies a well-defined lesion in the epiphysis of the proximal humerus. Histology shows polygonal cells, scattered giant cells and fine pericellular calcification. Which diagnosis best fits these findings?
9.
A 38-year-old man with a long-standing bony projection from the distal femur develops new pain and progressive enlargement after skeletal maturity. Which change is of greatest concern?
10.
A 48-year-old man has gradually progressive pelvic pain. Imaging reveals a lobulated destructive lesion with chondroid mineralization and extension into adjacent soft tissue. Which feature most strongly favours malignancy over a benign cartilage lesion?
11.
A 16-year-old boy presents with a painless hard swelling near the proximal tibia. Imaging shows a cartilage-capped projection from the metaphysis. Which additional radiological feature would best confirm the suspected diagnosis?
12.
A 14-year-old boy has a destructive distal femoral tumour with a large extraosseous component. MRI is obtained before biopsy, and chest imaging is included in the work-up. What is the main reason for evaluating the chest?
13.
A deep thigh tumour in a young adult contains primitive cells in abundant myxoid material. Delicate branching capillaries and scattered cells with indented nuclei are present. Which tumour type best fits these findings?
14.
A 16-year-old boy is referred with a suspected malignant tumour of the proximal tibia. Plain radiography has already demonstrated an aggressive lesion. Which investigation is most useful before biopsy to define the local anatomical extent?
15.
A large non-ossifying fibroma occupies a substantial portion of the distal tibial cortex in a 13-year-old boy. Which complication is most directly related to the size of the lesion?
16.
A 55-year-old woman has a rapidly enlarging uterine mass with areas of haemorrhage and necrosis. Histology reveals spindle cells with blunt-ended nuclei, marked atypia and numerous mitoses. Which diagnosis is most likely?
17.
A 61-year-old man has a rapidly enlarging deep soft-tissue mass. Histology shows bizarre malignant cells, marked nuclear variation and pleomorphic cells containing cytoplasmic lipid vacuoles. Which biological behaviour is most likely?
18.
A 62-year-old patient with a known visceral carcinoma develops multiple painful skeletal lesions. A student identifies them as primary malignant bone tumours because bone malignancy is present. Which epidemiological principle corrects this interpretation?
19.
A 16-year-old boy has a deep soft-tissue mass in the thigh. Histology shows tumour cells arranged in nests separated by fibrous septa. Cells at the centre of the nests are loosely attached. Which feature primarily produces the characteristic microscopic pattern?
20.
A 32-year-old woman presents with knee pain and reduced movement. Imaging shows an eccentric expansile lesion extending from the epiphysis to the subarticular bone of the distal femur. Histology reveals many multinucleated cells among mononuclear stromal cells. Which process is mainly responsible for the radiological bone destruction?
21.
A 13-year-old boy presents with fever, limb pain and swelling. Blood tests show leukocytosis and raised inflammatory markers. Radiography reveals a permeative diaphyseal lesion with a large soft-tissue mass. Antibiotics produce no improvement. Which investigation would most directly support the suspected tumour diagnosis?
22.
A 12-year-old child undergoes radiography after a sports injury. An eccentric metaphyseal cortical lesion with a sharply defined sclerotic border is found. The child has no symptoms attributable to the lesion. Which management principle is most appropriate?
23.
A 17-year-old boy has a painful metaphyseal lesion around the knee. Imaging shows mixed lysis and sclerosis with cortical destruction. Histology demonstrates pleomorphic cells, but no tumour matrix is seen in the initial small sample. What is the most appropriate interpretation?
24.
A malignant soft-tissue tumour in an adult contains highly pleomorphic cells with evidence of skeletal-muscle differentiation. Which subtype is most likely?
25.
A 36-year-old woman has a firm abdominal-wall mass that extends between skeletal-muscle fibres. The tumour consists of uniform spindle cells in long collagenous fascicles. Which feature best explains why complete surgical removal may be difficult?
26.
A patient with deep fibromatosis develops weakness and discomfort in the affected limb despite bland microscopic features. Which mechanism best explains these symptoms?
27.
A pelvic tumour in a young girl forms a polypoid mass beneath a mucosal surface. Histology shows a dense layer of malignant cells immediately below the epithelium. Which tumour is most likely?
28.
A pathologist must distinguish leiomyosarcoma from fibrosarcoma in a spindle-cell malignancy. Which morphological finding most strongly favours smooth-muscle differentiation?
29.
A 29-year-old woman has an incidental cartilaginous lesion in a phalanx. It is well circumscribed and has not changed on serial imaging. Which clinical development would most strongly justify reassessment for a malignant process?
30.
A 19-year-old man has intense nocturnal tibial pain. CT demonstrates a small cortical nidus with surrounding dense sclerosis. His pain improves significantly after a cyclooxygenase inhibitor. Which mechanism best accounts for this response?
31.
A 50-year-old man has a painless, slowly enlarging mass in the thigh. Imaging shows a deep soft-tissue lesion. Histology demonstrates mature adipocytes of unequal size with scattered atypical stromal cells. No marked pleomorphism or tumour necrosis is seen. Which diagnosis is most likely?
32.
A surgeon performs an unplanned biopsy through several muscle compartments before referral of a patient with suspected osteosarcoma. Which consequence is most important?
33.
A 15-year-old girl has a rapidly enlarging distal femoral mass. Radiography demonstrates cortical destruction, a soft-tissue component and interrupted periosteal elevation. Which interpretation best explains these radiological findings?
34.
A pathologist reviews a rapidly growing superficial spindle-cell lesion. Which additional finding would most strongly favour sarcoma rather than nodular fasciitis?
35.
A biopsy from a femoral shaft lesion in an adolescent shows sheets of monotonous round cells with scant clear cytoplasm. Which cellular feature most likely produces the clear appearance?
36.
A 7-year-old boy presents with nasal obstruction and facial swelling. Biopsy reveals small primitive cells mixed with larger cells containing deeply eosinophilic cytoplasm. Which process is demonstrated by the larger cells?
37.
A 17-year-old boy presents with increasing pain and swelling around the knee. Radiography shows a poorly defined metaphyseal lesion extending through the cortex into soft tissue. Biopsy demonstrates pleomorphic malignant cells surrounding irregular eosinophilic matrix. Which finding most strongly establishes the diagnosis?
38.
A 40-year-old woman undergoes removal of a uterine mass. It is sharply circumscribed and has a whorled cut surface. Microscopically, the cells are uniform with blunt-ended nuclei. Which additional finding would be most consistent with this diagnosis?
39.
A 20-year-old man presents with persistent back pain. Imaging reveals a 4-cm expansile lesion involving the posterior elements of a lumbar vertebra. Histology shows woven bone trabeculae rimmed by bland osteoblasts in vascular stroma. Which diagnosis is most appropriate?
40.
A 25-year-old woman develops a painful forearm nodule that has enlarged over three weeks. Biopsy shows plump spindle cells, extravasated red cells and abundant myxoid stroma. Numerous mitoses are present, but none are atypical. Which interpretation is most appropriate?
