A comprehensive assessment of frailty status on surgical, functional and oncologic outcomes in patients treated with partial nephrectomy-A large, retrospective, single-center study

Background: Partial nephrectomy (PN) is a challenging procedure, which can be associated with severe complications. In consequence, the search for accurate and independent indicators of unfavorable surgical outcomes appears warranted. We aimed at evaluating the impact of frailty status on surgical, functional and oncologic outcomes in patients undergoing PN for renal cell carcinoma (RCC).

Methods: A retrospective, single-center study including 1,282 patients treated with PN for clinically localized cT₁ RCC was performed. The modified Frailty Index (mFI) was used to assess preoperative frailty. Multivariable logistic, Poisson and linear regression analyses(MVA) tested the effect of frailty on complications, acute kidney injury(AKI), renal function decline after PN. Cumulative incidence and competing-risk analyses investigated survival outcomes.

Results: Of 1,282 patients, 220 (17%) were frail. Overall, 982 (76%) vs. 123 (9.6%) vs. 171 (13%) patients underwent open vs. laparoscopic vs. robot-assisted PN. Median follow-up was 66 (IQR: 35-107) months. At MVA, frailty status predicted increased risk of complications [Odds ratio (OR): 1.46, 95%CI 1.17-1.84; P < 0.001]. Moreover, frail patients were at higher risk of postoperative AKI (OR: 1.95, 95%CI 1.13-3.35; P = 0.01). In frail patients, renal function permanently decreased over time (P = 0.01) without any renal function plateau or improvement during the follow-up, which were instead observed in the nonfrail cohort. At competing-risks analyses, frailty status predicted higher risk of other-cause mortality [Hazard ratio (HR): 1.67, 95%CI 1.05-2.66; P = 0.02], but not of cancer-specific mortality (P = 0.3).

Conclusions: Frailty status predicts higher risk of adverse surgical outcomes after PN. Moreover, greater renal function decline was observed in frail patients, compared with nonfrail patients. Finally, the risk of OCM significantly overcomes the risk of dying due to RCC in frail patients.