Four different (A, B, C, D) renal tumors with granular cells

What's your guess for each and why?

Yes these pictures are from 4 different patients.  The answers are:

• A. Chromophobe RCC, eosinophilic type
• B. Oncocytoma
• C. Angiomyolipoma (myoid rich)
• D. Clear cell RCC

A few comments about the "granular" renal neoplasm. Obviously this is only one small high power field of a neoplasm. I hope that most people would agree the most important for a correct diagnosis of a difficult case is to look at all areas of the tumor and adequate sampling.  

• A: difficult to diagnosis - eosinophilic cell, may be perinuclear halo, slight irregular nuclear contour, and prominent cytoplamic membrane, and linear vascular pattern
• B: should be relatively easy - discohesive cells, round nuclei...
• C and D: almost impossible to tell the difference...will need to search for areas of fat and abnormal vessels for the diagnosis of angiomyolipoma and look for low grade clear cells with chicken-wire pattern vascular network for clear cell RCC.

 A嫌色性肾细胞癌

B嗜酸细胞瘤

CD血管平滑肌脂肪瘤

 嫌色性肾细胞癌。

应该说比较典型，瘤组织呈实体性结构，瘤细胞周有明显空晕。

 这里可以大胆的猜，试试看，还望老师多指导！

A:透明细胞肿瘤

B:嗜酸颗粒细胞肿瘤

C:血管平滑肌脂肪瘤，不排除脂肪肉瘤（粘液样，但没看到脂母细胞）

D:血管平滑肌脂肪瘤

C、D不好猜，也不知其它病史、肿瘤大小、边界、色泽等。