HISTORY:
A female in her early 40's with history of ESRD due to diabetic nephropathy presents with an exophytic solid mass in the lower pole of the left kidney. The CT scan showed a mass measuring approximately 4.3 x 4.3 x 4.9 cm. An image guided biopsy was performed, allowing consensus for a radical nephrectomy.
GROSS:
The specimen is designated "left kidney and ureter" and consists of a kidney and perinephric fat with an attached segment of ureter, renal vein, and artery that is 273.9 grams and 12.0 x 6.9 x 5.8 cm. The renal vein is 2.1 cm in length and 0.9 cm in diameter. The tumor is not present in the renal vein or its branches and is 4.6 cm from the vein margin. Located in the lower pole is a well-circumscribed, partially hemorrhagic, multicystic mass with no discernible solid component that measures 4.5 x 4.2 x 3.5 cm. The cysts contains clear or bloody fluid. The tumor abuts the renal sinus fat, pelvicalyceal system, and inked outer surface but does not involve them. The uninvolved renal parenchyma is unremarkable.
Remaining Positive IHC Stains: CAM 5.2, FH, Vimentin, CAIX (non-membranous staining), AMACR, RCC, and SDHB
Remaining Negative IHC Stain: Melan A, Inhibin, HMB45
What is the most likely diagnosis?
- MiT family translocation renal cell carcinoma
- Oncocytoma
- Chromophobe renal cell carcinoma (eosinophilic type)
- Clear cell renal cell carcinoma
- Eosinophilic solid and cystic renal cell carcinoma
Eosinophilic solid and cystic renal cell carcinoma