Primary signet-ring cell carcinoma of the urinary bladder

To perform a comprehensive review and analysis of the clinical characteristics of primary signet-ring cell carcinoma of the bladder cases reported in Japan. Primary signet-ring cell carcinoma of the bladder is a rare condition. To date, the largest case series conducted for this condition includes only 11 cases.

A search of published data was performed using the key words, "signet ring cell" and "urinary bladder." The Ichusi, which is the largest medical database in Japan, and the PubMed databases were searched. All articles reported from Japanese institutions were reviewed, regardless of their language. Overall, we identified 131 titles reported between 1981 and 2008. Meeting abstracts were excluded, but the unpublished cases managed at our institution were included. In all, 54 cases were comprehensively reviewed and analyzed.

The median age at diagnosis was 61.2 years with male dominance (2:1). Among the selected cases, 46% had stage IV tumors. The overall survival rate at 2 years was 43%. However, none of the patients with stage IV disease at diagnosis were alive at 2 years. Multivariate analysis revealed that tumor stage and elevated carcinoembryonic antigen levels were significant prognostic factors. Of the 8 patients who were followed up for > 2 years and showed no evidence of recurrence, 7 were treated by either radical or partial cystectomy.

Although the overall prognosis of this condition is poor, it is still dependent on the tumor stage at diagnosis. With early diagnosis and intervention, it may be possible to achieve long-term survival.