BackgroundIn China, upper tract urothelial carcinoma (UTUC) is less prevalent but more malignant in males. This study investigates the prognostic factors and causes of gender-based differences in Chinese populations.MethodsBetween 1999 and 2011, 687 UTUC patients who underwent surgery were utilized for this study. We evaluated the differences in oncological characteristics, epigenetic biomarkers, cancer-specific survival (CSS), bladder recurrence (BR) rate, and contralateral upper tract recurrence (CUTR) rate. Smoking history, benzene exposure history, and the history of using aristolochic acid (AA) containing herbs were analyzed in detail.ResultsCompared with male patients, female patients showed poorer renal function, lower proportions of tumor stage III/IV, and smaller tumor diameters. The CSS in male patients was lower than that in female patients. Significant gender-related differences were observed concerning various prognostic factors. In female patients, poorer survival rates were attributed to the primary tumor location in the ureter, large diameter primary tumors, severe chronic kidney disease, papillary tumor architecture, high tumor stages, positive N status, and methylated ABCC6 promoters. In male patients, older age, ipsilateral hydronephrosis, large tumor diameters, sessile tumor architecture, high tumor stages, and methylated TMEFF2 promoters were associated with higher cancer-specific mortality. AA might be the main cause of these gender-based differences. The AA-induced UTUC patients presented smaller tumor diameters, lower tumor stages, fewer positive N statuses, more multifocal tumors, lower methylation indices, and poorer renal function. Although AA-induced UTUC patients exhibited better survival rates, BR and CUTR rates were significantly worse.ConclusionIn China, there exist significant AA-induced differences between male and female UTUC patients. The bladders and contralateral upper urinary tracts of AA-induced UTUC patients should be carefully monitored after surgery.