Clinical, Prognosis, and Treatment Effect Features Analysis of Metachronous and Synchronous UTUC and BUC

ObjectiveTo provide a comprehensive understanding of the clinical features of patients with synchronous and metachronous upper tract urothelial carcinoma (UTUC) and bladder urothelial carcinoma (BUC) and inform surgical and postoperative adjuvant treatment planning.Patients and MethodA total of 292 consecutive patients with synchronous and metachronous UTUC-BUC were retrospectively enrolled and were categorized into three groups: (1) UTUC metachronous BUC (N=185, UTUC-mBUC), (2) BUC-metachronous UTUC (N=43, BUC-mUTUC), (3) synchronous UTUC-BUC (N=64, sUTUC-BUC). We compared pathological characteristics and survival data among groups with Wilcoxon's rank sum tests, Pearson's chi-squared, and the Kaplan–Meier method.ResultsIn the sUTUC-BUC group, a higher proportion of patients exhibited UTUC tumors with grade G3 (56%, p=0.001) and stage T4 (6%, p<0.001) than group UTUC-mBUC (G3=16%, T4= 0%). The proportion of patients with variant histology subtype in group sUTUC-BUC was higher than that of metachronous UTUC-BUC, involving squamous (p=0.003), adenoid (p=0.012), and sarcomatoid (p<0.001) differentiation. It was also observed that the maximum diameter of the UTUC tumor of group sUTUC-BUC (median=3.5) was significantly larger than group UTUC-mBUC (median=2.5, p=0.002) and group BUC-mUTUC (median=2.2, p<0.001). Notably, sUTUC-BUC has an increased risk of cancer-specific death compared with UTUC-mBUC (p<0.001) and BUC-mUTUC (p<0.001). ໿On multivariable Cox regression, synchronous UTUC-BUC was ໿an independent predictor of both RFS (p<0.001; vs.UTUC-mBUC: HR 0.555, p=0.004; vs.BUC-mUTUC: HR 0.279, p<0.001) and CSS (p<0.001, HR 29.737). Moreover, sUTUC-BUC showed a better response to intravesical therapy and chemotherapy with higher cancer-specific survival (p<0.001) and recurrence-free survival (p=0.034).ConclusionsThe prognosis and pathological characteristics among different metachronous and synchronous UTUC and BUC were diverse. The synchronous UTUC-BUC group showed variant histology subtype, high-grade tumors, advanced tumors, multifocal UTUC, worse cancer-specific survival, but better response to intravesical therapy and chemotherapy.MicroAbstractTo provide a comprehensive understanding of the clinical features of UTUC-BUC, we performed a retrospective study evaluating 292 patients diagnosed with UTUC with synchronous or metachronous BUC.The results showed that the synchronous UTUC-BUC group showed clinical features related to poor prognosis, such as high-grade tumors, advanced tumors, and worse CSS, but better response to intravesical therapy and chemotherapy.