Long-term clinical outcome of inverted urothelial papilloma including cases with focal papillary pattern: is continuous surveillance necessary?

Abstract

Objective: To investigate the necessity for continuous cystoscopic surveillance of inverted papilloma (IP), including tumors exhibiting mixed morphology (IP with focal papillary architecture).

Methods: We retrieved all cases of de novo ("primary") IP, diagnosed in our institution during 10 years (from January 2000 to December 2009), from the information database. Patients with a history of urothelial carcinoma or concurrent urothelial carcinoma were excluded. Surveillance was performed by routine cystoscopy, and follow-up was obtained from our institutional and regional clinical and pathology databases.

Results: We identified 35 patients with IP, including 3 with focal papillary architecture. Mean patient age was 60 years (range, 26-88) with male-to-female ratio of 1.9:1. Most common tumor location was urinary bladder (86%), followed by urethra (14%). Focal papillary architecture was identified in 3 patients (aged 51, 52, and 78 years). Mean follow-up was 66 months (median 68; range, 11-132). Only 1 male patient (age 81) had a subsequent diagnosis of IP on follow-up cystoscopy at 9 months; no recurrence or progression was documented in the other patients diagnosed with IP.

Conclusion: The absence of progression of IP on long-term follow-up in this study strongly argues against the need of continuous surveillance for patients in whom (1) strict diagnostic criteria are followed, (2) a complete resection can be ascertained, and (3) no previous or concurrent urothelial malignancies are documented. In this study, the 3 patients with IP showing focal papillary architecture had a benign course, similar to the previously documented cases.