Clear Cell Tubulopapillary Renal Cell Carcinoma
Differential Diagnosis
| Papillary Renal Cell Carcinoma |
Clear Cell Tubulopapillary Renal Cell Carcinoma |
| Clear cell cytoplasm, if present, is focal |
Widespread clear cell cytoplasm, frequently subnuclear/basal |
| Frequently has foamy macrophages, psammoma bodies, stromal hemosiderin |
Lacks foamy macrophages, psammoma bodies, stromal hemosiderin |
| May have high grade nuclear features and necrosis |
Low grade nuclear features, no necrosis |
| CD10 pos, Racemase/AMACR pos |
CD10 neg, Racemase/AMACR neg |
| Conventional Clear Cell Renal Cell Carcinoma |
Clear Cell Tubulopapillary Renal Cell Carcinoma |
| Sheets and clusters of cells with extensive vascular network |
Nearly all have branched tubules and anastomosing ribbons |
| Solid areas have clusters more than two cells wide |
Solid areas usually formed by compressed tubules, each only two cells wide |
| May have high grade nuclear features, vascular invasion and necrosis |
Low grade nuclear features, no invasion or necrosis |
| Cysts frequently due to degeneration, lined in areas by multiple layers of cells |
Uniformly lined by single layer of cells |
| Clear cytoplasm apical or diffuse, non-localized |
Frequent regular basal clearing, resembling interval endometrium |
| Usually CK7 neg, CD10 pos |
CK7 pos, CD10 neg to focal |
| Xp11 Translocation Renal Cell Carcinoma |
Clear Cell Tubulopapillary Renal Cell Carcinoma |
| Frequently occurs under age 20 |
Mean age 60 |
| Typically high grade nuclear features |
Low grade nuclear features |
| Voluminous cytoplasm |
Moderate amount of clear cytoplasm |
| TPE3 immunostain or FISH positive in >80% |
Lacks Xp11 translocations |
| CK7 and other keratins negative to weak, CD10 pos, Racemase/AMACR pos |
CK7 strong pos, CD10 neg, Racemase/AMACR neg |
| Multilocular Cystic Renal Cell Carcinoma |
Clear Cell Tubulopapillary Renal Cell Carcinoma |
| No tubules, ribbons or papillae |
Nearly all have branched tubules, anastomosing ribbons and papillae |
| Clear cytoplasm apical or diffuse, non-localized |
Frequent regular basal clearing, resembling interval endometrium |
| Nests of clear cells in septa |
Nests of clear cells if present are formed by compressed tubules, each of which is only two cells wide |
| CK7 neg, CD10 pos |
CK7 pos, CD10 neg to focal |
