Multilocular Cystic Renal Neoplasm of LMP : Microscopic
Multilocular cystic renal neoplasm of low malignant potential: The cysts are lined by a single layer of tumor cells with abundant clear cytoplasm. The are small nuclei with no nucleoli (WHO/ISUP Grade 1 or 2). Some cases may show multilayering of cells or small intracystic papillations. The fibrous septa often show clusters of identical tumor cells. In addition, septa may have areas of calcification or ossification. Feature that are not compatible with the diagnosis include: nodules of clear cells with expansile growth, necrosis, vascular invasion, and sarcomatous features.