Successful Treatment of Metastatic Urothelial Carcinoma after Accurate Diagnosis by Immunohistochemistry.

Urothelial carcinoma usually presents with hematuria, but cases of multiple lymphadenopathy with elevated S-pancreas-1 antigen (SPan-1) levels have not been reported. A 62-year-old Japanese man with lymphadenopathies was diagnosed with an adenocarcinoma of unknown origin and transferred to our hospital for further diagnosis. Serum carbohydrate antigen 19-9 and SPan-1 levels were extremely elevated. Uroplakin III immunostaining was positive in the inguinal lymph node, and cystoscopy revealed the presence of invasive urothelial carcinoma. Treatment with cisplatin and gemcitabine promoted a complete metabolic response for > 4 years. The detection of uroplakin III and serum SPan-1 might help diagnose urothelial carcinoma.