Renal Complications in Solid Tumor Patients Referred to an Onconephrology Clinic: A Three-Year Italian Experience

Onconephrology represents a burgeoning subspecialty within nephrology, dedicated to ensuring optimal oncological management for cancer patients with pre-existing or cancer-therapy-induced renal impairment. Epidemiological data regarding the early impact of renal function alterations in Italian oncology patients are currently lacking. This study presents a three-year single-center experience from an onconephrology clinic, evaluating patients with solid tumors and renal abnormalities, specifically acute kidney injury (AKI) or proteinuria. A total of 254 patients with solid malignancies were included. Among these, 153 (60.2%) were referred due to AKI, predominantly AKIN stages I-II, with 71 cases (46.4%) attributed to oncological treatment. Notably, antineoplastic therapy was permanently discontinued in only 27 patients (13.1%). The most frequent tumor types were pulmonary (17.5%) and gynecological (17.9%) cancers. Checkpoint inhibitors were the therapies most commonly associated with AKI. During the follow-up period, 83 of the 254 patients (34.5%) died, with 46 (55%) of these having experienced concurrent AKI, suggesting a potential risk for chronic kidney disease development. Among the surviving patients, 71% exhibited a decline in estimated glomerular filtration rate of <30 ml/min. This experience underscores the intricate relationship between cancer therapies and renal function, highlighting the critical need for early and continuous onconephrological assessment in this patient population.