Name: Josephine Bowen

Theme: Bone Histopathology

OPTION LIST

A	Ewing’s sarcoma	I	Primary osteosarcoma
B	Chondrosarcoma	J
C	Osteoarthritis	K
D	Osteogenesis imperfecta	L
E	Osteomalacia	M
F	Osteomyelitis	N
G	Osteopetrosis	O
H	Osteoporosis	P

For each scenario below, choose the most appropriate answer from the list above. Each option may be used once, more than once or not at all.

1. A 45-year-old Asian female presents with generalised bone pain. Histological findings are of increased osteoid volume with widened osteoid seams and reduced mineralization. Her diet is vegan.

2. A 15-year-old male presents with a 2-month history of increasing pain in his right upper arm. Bone biopsy reveals sheets of cells with small, primitive nuclei and scanty cytoplasm. A positive immunoreactivity is seen with the MIC2 (CD99) antibody.

3. Electronmicroscopy shows bone thinning and wide separation of trabecular plates in a postmenopausal Caucasian female of slender build.

4. Mottled rarefaction and lifting of the periosteum are seen on X-ray of the femur. Bone biopsy reveals an intense neutrophilic inflammatory infiltrate.

5. A 20-year-old male complains of a progressively enlarging painful mass on his right upper arm. Radiology demonstrates a lytic lesion of the proximal humerus with an accompanying Cadman triangle. Microscopically, pleomorphic mesenchymal cells producing dark-staining osteoid are seen.

ANSWERS

1. E

2. A

3. H

4. F

5. I