The Role of Fluorescence In Situ Hybridization for Predicting Recurrence after Adjuvant bacillus Calmette-Guérin in Patients with Intermediate and High Risk Nonmuscle Invasive Bladder Cancer: A Systematic Review and Meta-Analysis of Individual Patient Data

PURPOSE: The objective of this study was to assess the value of fluorescence in situ hybridization to predict early recurrence in patients with nonmuscle invasive bladder cancer at intermediate and high risk treated with bacillus Calmette-Guérin. MATERIALS AND METHODS: We performed a systematic review using MEDLINE®, Embase® and the Cochrane Library. Individual patient data from prospective observational studies of fluorescence in situ hybridization in patients treated with bacillus Calmette-Guérin were included. A 2-stage individual patient data meta-analysis was done to assess the value of fluorescence in situ hybridization to predict tumor recurrence after bacillus Calmette-Guérin induction therapy. RESULTS: From a total of 4 studies we obtained individual data on 422 patients, of whom 408 with a median followup of 18.8 months were included in the final analysis. When fluorescence in situ hybridization was positive, the recurrence HR was 1.20 (95% CI 0.81-1.79) before bacillus Calmette-Guérin (time 0), 2.23 (95% CI 1.31-3.62) at 6 weeks (time 1), 3.70 (95% CI 2.34-5.83) at 3 months (time 2) and 23.44 (95% CI 5.26-104.49) at 6 months (time 3). CONCLUSIONS: A positive fluorescence in situ hybridization test after bacillus Calmette-Guérin correlated with higher risk of recurrent tumor. Fluorescence in situ hybridization could aid urologists in risk stratifying and counseling patients. Based on the HR and the narrowest CI the preferred timing of fluorescence in situ hybridization is 3 months after transurethral resection of bladder tumor. This is also in time for patients in whom induction therapy fails to enter clinical trials or change the treatment strategy.