"Epidemiology "
"Clinical presentation "
"Pathology "
"Radiographic features "
"CCTL usually presents as an incidental peripheral pulmonary nodule. On histology it shows evidence of perivascular or melanocytic differentiation, being negative for cytokeratin and epithelial membrane antigen, but positive for HMB-45 and sometimes S-100. This immunoprofile distinguishes CCTL from both metastatic renal cell carcinoma and primary clear cell carcinomas of the lung, which are cytokeratin-positive and lack HMB-45 reactivity."
"CCTL usually presents as an incidental peripheral pulmonary nodule. On histology it shows evidence of perivascular or melanocytic differentiation, being negative for cytokeratin and epithelial membrane antigen, but positive for HMB-45 and sometimes S-100. This immunoprofile distinguishes CCTL from both metastatic renal cell carcinoma and primary clear cell carcinomas of the lung, which are cytokeratin-positive and lack HMB-45 reactivity."
"CCTLs are composed of large polygonal cells with clear cytoplasm because the abundant glycogen dissolves during standard processing. Glycogen is a metabolic product of perivascular epitheliod cells. Periodic acid-Schiff (PAS) staining highlights glycogen and is typically positive. CCTLs are immunoreactive for HMB-45 and vimentin, but negative for cytokeratin and epithelial markers, supporting perivascular or melanocytic differentiation. The absence of cytokeratin and epithelial membrane antigen helps distinguish CCTL from metastatic renal cell carcinoma and other clear cell neoplasms 7."
"It was initially described by A A Liebow and B Castleman in 1963 2."
Expected headings
"Epidemiology "
"Clinical presentation "
"Pathology "
"Radiographic features "
"CT"
"There are few reported cases, affecting males and females in their third to seventh decades 7."
"Nodules are solitary, smooth and round, well-defined and homogeneous, located in the lung periphery."
"History and etymology"