Prognostic impact of the modified frailty index after radical surgery for upper urinary tract urothelial carcinoma

Abstract Introduction Radical nephroureterectomy is the gold standard treatment for non-metastatic upper tract urothelial carcinoma. It is a major surgery associated with significant morbidity, particularly in elderly and frail patients. The modified five-factor frailty index (mFI-5) is a recently used tool to predict postoperative outcomes. This index has been established as a prognostic factor in several cancers. The objective of this study was to evaluate the impact of mFI-5 on the oncological prognosis of patients treated with a Radical Nephroureterectomy for non-metastatic upper tract urothelial carcinoma. Patients and methods In this multicentric, retrospective, study we collected all patients managed for non-metastatic upper tract urothelial carcinoma who underwent radical nephroureterectomy between 2015 and 2023. The mFI-5 was calculated based on the presence of the following five comorbidities: congestive heart failure within 30 days before surgery, diabetes mellitus, chronic obstructive pulmonary disease, partially or totally dependent functional health status at the time of surgery, and hypertension requiring antihypertensive treatment Patients were grouped as not frail (mFI-5 = 0), intermediate (mFI-5 = 1), and severely frail (mFI-5 ≥ 2). Surgical outcomes were evaluated based on perioperative complications and length of hospital stay. Prognostic outcomes included progression-free survival (PFS) and overall survival (OS). Results We included 170 patients. From these patients, 47% (n = 80) were not frail, 30.58% (n = 52) were intermediate, and 22.35% (n = 38) were severely frail. Frail patients were more likely to be older (p = 0.03), current smokers (p = 0.02), and to have chronic kidney disease (p = 0.01). Patients with intermediate or severe frailty were more likely to experience postoperative acute kidney injury (p = 0.012), thromboembolic event (p = 0.003), significant blood loss (p = 0.041), and require vasopressor support (p = 0.01). Frail patients had a longer hospital length of stay (p < 0.001) and unplanned readmission (p = 0.02). The 2-year PFS rates were 45% in the severely frail group, 64% in the intermediate group and 87% in the low mFI-5 group, while the corresponding 2-year OS rates were 46%, 78%, and 92% respectively. Conclusion Frailty, as measured by the mFI-5, is a predictor of postoperative complications, functional decline, and poor oncological prognosis after RNU for UTUC. Its preoperative assessment is crucial for personalized patient management.