Tubulocystic Carcinoma of the Kidney

Definition

Cytologically high grade renal neoplasm composed of densely packed cysts and tubules

Closely packed variably sized tubules and cysts
- 0.05-2 mm diameter
- Separated by bland fibrous stroma
  - No desmoplasia or ovarian stromal features
Lined by cuboidal to flattened and hobnail cells
- Abundant eosinophilic or amphophilic cytoplasm
  - Cells resemble those of oncocytoma but show uniform prominent nucleoli
- Focal clear cell or papillary features are seen in rare cases
- No foamy macrophages or psammoma bodies
High grade nuclear features
- Large hyperchromatic nuclei
- Prominent round nucleoli
- Mitotic figures and necrosis rare
Sharply circumscribed and spongy gross appearance

John P Higgins MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting, last update:: 1/24/11, 6/2/15