Editorial Comment.

This is a thought provoking article. Easily accessible additional information would have answered some questions. What was the final pathology result of the prostatic urethra? The riddle of the low incidence of urethral recurrence following orthotopic reconstruction compared to a not perfused but retained urethra continues. The most simple explanation of these findings might be that patients selected for orthotopic reconstruction present with more favorable disease characteristics. In the analysis by Boorjian et al an antitumorigenic "ileal factor" is reported (reference 2 in article). While the urethral recurrence rate in Bern is not lower than in other reported series following orthotopic reconstruction, the biological aggressiveness of urethral recurrence seems to be much less in Bern. In this context Niegisch et al investigated whether an immune response of urethral tissue potentially induced by contact of the urethra with ileal tissue might be present as a morphological substrate of an “ileal factor.” When comparing patients with a neobladder to control patients, the distribution of B-cells and T-cells was statistically not different. However, a trend toward an increased presence of B-cells in the urethral tissues of orthotopic reconstructions, which could become relevant in a larger study, might be suggestive of an immunological response induced by connecting urethral and ileal tissue.