[Signet-ring cell carcinoma of the urinary bladder: study of 4 cases and review of the literature].

Four cases of primary signet-ring cell adenocarcinoma of the urinary bladder are described. All patients were men, with ages ranging from 46 to 81 years. The number of signet-ring cells varied and showed a direct correlation with poor prognosis. PAP analyses of acid phosphatase and prostate-specific antigen were negative. The results show that signet-ring cell carcinoma has a poor prognosis. This cell type should be sought in all bladder carcinomas since its presence is likely to worsen prognosis.