Immunohistochemical localization of the IAP protein survivin in bladder mucosa and transitional cell carcinoma.

In the current study, the immunohistochemical localization of survivin was correlated with the histologic diagnosis in healthy transitional cell epithelium, transitional cell carcinoma (TCC) in situ, and TCC of the urinary bladder. Forty-five TCCs (grades 1-3, 15 of each), 14 cases of TCC in situ, and II healthy bladder mucosal specimens were selected from archival collections of formalin-fixed bladder tissues. Slides were reacted with an anti-survivin antibody using a conventional immunohistochemical method and then were scored for nuclear and cytoplasmic staining. Statistical analysis of survivin expression was performed to evaluate the correlation of staining pattern with histologic diagnosis and clinical outcome. Nuclear staining for survivin was detected in 26 of 45 TCCs and in 2 of 14 cases of TCC in situ, but was not detected in healthy bladder mucosa. The association of nuclear staining with TCC versus both healthy bladder mucosa and TCC in situ was statistically significant (P < 0.001). Patients with TCC and a nuclear pattern of survivin localization had a greater period of disease-free survival (27.2 months) than was observed in patients with TCC that showed no nuclear staining for survivin (9.9 months); however, the differences were not statistically significant. Nuclear localization of survivin is a marker of TCC but is rarely present in premalignant or benign bladder mucosal specimens.