ITALIAN REGISTRY ON RARE UROLOGICAL TUMORS (MEET-URO-23): THE FIRST ANALYSIS ON COLLECTING DUCT CARCINOMA OF THE KIDNEY

Introduction Rare genitourinary tumors are lacking of randomized and observational data. We aimed to describe the clinical characteristics and outcomes of patients with collecting duct carcinoma (CDC) through the Meet-URO 23/I-RARE database. Materials and methods We performed a multicentric retrospective-prospective study within the Meet-URO network, enrolling patients from March 2021 (retrospectively up from 2011) until March 2023. The primary objective was to describe the clinical characteristics of patients with CDC, the secondary objectives were to assess the oncological outcomes in terms of relapse-free survival (RFS), progression-free survival (PFS), overall survival (OS) and objective response rate (ORR) to treatment. Results 37 patients with CDC were enrolled. Four patients underwent only surgery, 33 received first-line systemic therapy. Median OS was 22.1 months (95%CI 8.9-31.9). Median RFS for patients with localized disease at onset (n = 30) was 3.7 months (95%CI 1.9-12.8), median PFS for first-line treatment was 3.3 months (95%CI 2.7-9.9), with an ORR of 27%. Female sex and good performance status (PS) were associated with longer PFS (p = 0.072 and p < 0.01, respectively) and OS (p = 0.030 and p = 0.141, respectively). Conclusions Patients with CDC had dismal prognosis, with scarce benefit from the available treatments. Female sex and good PS seemed to be associated with better prognosis. Micro-Abstract Aim. The Meet-URO 23/I-RARE is a multicentric retrospective-prospective study on patients with rare genitourinary cancer.Methods. The objectives were to describe the characteristics and outcomes of patients with collecting duct carcinoma (CDC) and assess the oncological outcomes.Results. The median overall survival (OS) of the 37 patients was 22.1 months. Median relapse-free survival after surgery was 3.7 months; median progression-free survival (PFS) for first-line treatment (n=33) was 3.3 months. Female sex seemed to have longer OS (p=0.030), good performance status (PS) patients appeared to have better PFS (p<0.01).Conclusions. Although showing dismal prognosis, with scarce benefit from treatments, female sex and good PS showed better outcomes.