Impact of the preoperative modified 5-item frailty index on the efficacy of neoadjuvant chemotherapy in patients with muscle invasive bladder cancer.

Purpose: We aimed to determine the optimal treatment strategy for MIBC patients undergoing neoadjuvant chemotherapy (NAC) followed by radical cystectomy. We investigated whether preoperative frailty influences the efficacy of NAC by evaluating the Modified 5-item Frailty Index (mFI-5), which was developed as a comprehensive geriatric evaluation tool with a reduced number of variables to simplify data collection.

Methods: This retrospective study included 356 MIBC patients. Clinical information was collected retrospectively from medical records. Preoperative frailty was evaluated according to the mFI-5 score, and associations between NAC and clinical outcomes were investigated. Overall survival (OS) was evaluated by the Kaplan-Meier method and a Cox proportional hazard model.

Results: Patients who received NAC had significantly lower mFI-5 scores (P = 0.021) than those who did not. Although the preoperative mFI-5 score had a minor impact on other clinicopathological parameters, a significant difference in OS was found between patients mFI-5-low and mFI-5-high groups (P = 0.036). Furthermore, NAC significantly improved OS, especially in patients in the mFI-5-low group (P = 0.007), whereas no significant difference was found in patients in the mFI-5-high group. In patients who received NAC, the eGFR (HR=2.12, P = 0.024), pT stage (HR=2.29, P = 0.017), pN stage (HR=2.14, P = 0.044), and mFI-5 score (HR=2.23, P = 0.020) were independent predictors of OS.

Conclusion: In patients who received NAC, the preoperative mFI-5 score and renal function were significantly associated with OS. Preoperative frailty, as evaluated by the mFI-5, might be an important factor for determining the indications for NAC in MIBC patients.