A huge extrarenal cell carcinoma developing from a heterotopic renal anlage with distant metastases: case report and literature review.

Renal cell carcinoma (RCC) is the most common type of renal tumor arising from the proximal renal tubules. Extrarenal RCC is a rare case in which a tumor is found outside the kidney with no primary kidney tumor. Some theories suggest that these tumors arise from mesoderm remnant. Here, we present a unique case, the fourth in literature, of peri-renal, Extrarenal RCC case and the first case with a huge mass with distant metastases and aggressive progression.