Spindle cell carcinoma progressed from transitional cell carcinoma of the urinary bladder

The author reports a very rare case of spindle cell carcinoma (SpCC) of the urinary bladder progressed from ordinary papillary transitional cell carcinoma (TCC). A 63-year-old man complained of hematuria. A transurethral endoscopic examination revealed a papillary tumor, and transuthetral resection of bladder tumor (TUR-BT) was performed and was diagnosed as ordinary papillary urothelial TCC. Since then, he was treated with TUR-BT eight times. Chemotherapy, radiation, radical cystectomy and lymph nodes dissection were performed 16 years after the first TUR-BT. However, he developed rectal mucosal metastasis. He is now alive 17 years after the first presentation. All the TUR-BT specimens were ordinary papillary TCCs without invasion (pTa). Immunohistochemically, the TUR-BT specimens were positive for pancytokeratin, high molecular weight cytokeratin (CK), CK 5/6, CK 7, CK 18, CK 19, CK 20, p53, p63, Ki-67 (10%), and negative for other antigens examined including vimentin. The cystectomy bladder specimens show broad ulcers and polypoid lesions, and malignant spindle cells (SpCC) invading into muscular layer were present. No TCC elements were recognized. The tumor cells were positive strongly for vimentin, and less strongly for pancytokeratin, high molecular weight cytokeratin, CK 5/6, CK 14, CK 18, p53, p63 and Ki-67 (95%), and negative for other antigens examined. The rectal metastatic lesion showed SpCC without TCC elements, and were strongly positive for vimentin, and weakly positive for pancytokeratin, S100 protein, p53, p63, Ki-67 (90%), neuron-specific enolase, CD56, KIT and PDGFRA. It was negative for other antigen examined. It is strongly suggested that the present SpCC were progressed from ordinary TCC.