Recurrent transitional cell carcinoma of the bladder: A mixed nested variant case report and literature review.

Nested variant of urothelial cell carcinoma (NVUC) is a rare histological entity, with about 80 reported cases. It has a deceptively benign appearance with an aspect characterized by confluent small nest or urothelial's cell tubules. This tumour often resembles inverted papilloma, von Brunn's nests (VBNs), cystitis cystica, nephrogenic metaplasia and sometimes usual transitional cell cancer.

Incidental prostatic stromal tumor of uncertain malignant potential (STUMP): histopathological and immunohistochemical findings.

Stromal prostate tumors are rare neoplastic proliferative lesions that have been classified into prostatic stromal tumor of uncertain malignant potential (STUMP) and prostatic stromal sarcoma (SS) based on these criteria: stromal cellularity, presence of mitotic figures, necrosis, and stromal overgrowth. A prostatic stromal tumor of uncertain malignant potential (STUMP) is a non-epithelial, mesenchymal spindle-cell tumor that can be classified as a specialized stromal tumor of the prostate. STUMPs have the capability to diffusely infiltrate the prostate gland and extend into adjacent tissues.