Case of the Month
Peripheral Lung Tumor
A well-circumscribed peripheral lung tumor measuring 3 cm in diameter was discovered on a routine X-ray examination of an otherwise healthy 50-year-old man. The tumor was positive for CD34, Bcl-2, CD99, and STAT6, and showed low proliferative activity by MIB1 (Ki-67) immunostaining. Cytogenetic analysis revealed no evidence of X;18 translocation.
What is the most likely diagnosis?
A. Synovial sarcoma
B. Benign fibrous histiocytoma
C. Solitary fibrous tumor
D. Myopericytoma
D. Malignant mesothelioma
We will reveal the answer in next month’s issue!
Do you think you have a good case of the month? Email it to [email protected]
Answer to last month’s Case of the Month…
A. Systemic lupus erythematosus
The light microscopy of this periodic acid-Schiff stained slide shows marked thickening of the capillary loops, colloquially known as “wireloops.” The electron microphotograph shows osmiophilic deposits on the sub-endothelial side of the capillary loop and also in the mesangial area. These findings are diagnostic of lupus nephritis, a common feature of systemic lupus erythematosus.
Submitted by Ivan Damjanov, The University of Kansas, Kansas City, USA.
