Subclassification of pT3 upper tract urothelial carcinoma: a multicenter retrospective study

Purpose The prognosis of patients with pT3 upper tract urothelial carcinoma (UTUC) varies. The current study aimed to further classify patients with pT3 UTUC into different survival outcome groups based on tumor location and site of invasion. Methods This retrospective study included 323 patients with pT3 UTUC who underwent nephroureterectomy at 11 hospitals in Japan. Histological and clinical data were obtained via a chart review. Univariate and multivariate Cox proportional hazards analyses showed the effect of different variables on recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS). Results The median age of the patients was 72 years. Patients with pT3 UTUCs were divided into two groups: those with renal parenchymal invasion only (pT3a, n = 95) and those with peripelvic or periureteral fat invasion (pT3b, n = 228). pT3b UTUC was significantly associated with hydronephrosis, low preoperative estimated glomerular filtration rate (eGFR), histological nodal metastasis, nuclear grade 3, lymphovascular invasion (LVI), carcinoma in situ, and positive surgical margin. Based on the univariate analyses, patients with pT3b UTUC had a significantly lower 5-year RFS (42.4% vs. 70.1%, p < 0.0001), 5-year CSS (54.3% vs. 80.0%, p = 0.0002), and 5-year OS (47.8% vs. 76.8%, p < 0.0001) than those with pT3a UTUC. According to the multivariate analyses, nodal metastasis, LVI, adjuvant chemotherapy, preoperative eGFR, nuclear grade (RFS only), surgical margin (RFS only), and Charlson comorbidity index (OS only), but not pT3b stage, were associated with survival. Conclusion Compared with pT3a UTUC, pT3b UTUC was significantly associated with worse histological features, consequently resulting in unsatisfactory survival outcomes.