Procedure: Laparoscopic radical nephrectomy. 

Gross description: Specimen submitted in a formalin container consists of a nephrectomy specimen with perinephric fat and 9 cm long ureter. A circumscribed, pale sub capsular tumor measuring 3.0 x 2.2 x 2.0 cm is seen at the lower pole of the right kidney. Adjacent to the main tumor, there is another, smaller discrete tumor nodule measuring 1.5 cm in maximum dimension, abutting the renal pelvis. The rest of the kidney is unremarkable.

Diagnosis: Chromophobe renal cell carcinoma. Histologic grade (Fuhrman nuclear grade): G2. Two discrete tumor nodules, 3.0 cm and 1.5 cm in maximum dimensions respectively (gross examination). Smaller tumor nodule mainly present in the fat of renal pelvis. Negative for perinephric tumor infiltration or lymphovascular invasion. No necrosis or sarcomatoid areas are identified. The ureter and hilar blood vessels are unremarkable and free of any tumor invasion. Pathologic staging;  pT1a, pNx, pMx.

Immunohistochemical staining:  The neoplastic cells are also strongly positive for colloidal iron stain and EMA (Monoclonal M. Anti-human-Clone E29, Monoclonal M. Antibody-Clone GP1.4). Very occasional cells are CK7 (Mono M. Anti-human-Clone OV-TL 12/30) positive. The cells are negative for Vimentin (Monoclonal M. Anti-Vimentin-Clone V9) and CK20 (Monoclonal M. Anti-human-Clone Ks20.8).