Sex differences of upper tract urothelial carcinoma: results from the Surveillance, Epidemiology, and End Results database and a single-center experience / 中华泌尿外科杂志

ABSTRACT

Objective:To validate gender-related differences in patients with upper tract urothelial carcinoma (UTUC).Methods:We used a method of combination of SEER database analysis and validation in our center. We selected 2 125 men (57.8%) and 1 552 (42.2%) women who underwent radical nephroureterectomy (RNU) for UTUC between 1995 and 2015 within the surveillance, Epidemiology, and End Results registries (SEER). In male cases, the median age was 71(22-99)years old, median follow-up time was 53.0 (0-227) months, 902 (89.5%) cases were Caucasian, 1 384 cases (65.1%) were located in the renal pelvis, and 810(38.1%) cases were T 3-T 4. For female cases, the median age was 73.6(25-99)years old, median follow-up time was 53.1(0-226) months, 1 417(91.3%) cases were Caucasian, 1 043 cases (67.2%) were located in the renal pelvis, and 508 (32.7%) cases were T 3-T 4. The analysis of SEER database showed that female patients were older compared to male patients ( P=0.002), the proportion of T 3-T 4 was even lower ( P=0.028). There were no statistically significant differences in race, tumor location, and follow-up time between males and females (all P>0.05). We also enrolled 131 men (55.3%) and 106 women (44.7%) who underwent RNU for non-muscle invasive (T a/T is/T 1) UTUC between January 2000 and January 2015. These patients had no history of bladder cancer, UTUC and kidney transplantation. Preoperative cystoscopy was performed to confirm the absence of bladder tumor. The male group was (65.8±12.4)years old, with history of aristolochic acid medications in 7(5.3%) cases, 98 smoking cases (74.8%), and estimated glomerular filtration rate (eGFR) of (64.2±29.4)ml/(min·1.73 m 2). In the female group, mean age was (66.7±11.9)years, 14 (13.2%) cases had history of aristolochic acid medications, 16(15.1%) had history of smoking, eGFR (56.3±27.9) ml/(min·1.73m 2). Compared with female patients, male patients tended to had less aristolochic acids exposure (5.3% vs.13.2%, P<0.001), frequent smoking (74.8% vs. 15.1%, P<0.001) and better renal function ( P=0.036). The Kaplan-Meier test was used for time-to-event analysis. Univariate and multivariate logistic regression models were adopted to examine the effect of gender on the development of T 3-T 4 tumor. Univariate and multivariate Cox regression analyses were used to assess the roles of factors on overall survival (OS) in both SEER and cases in our center, and competing-risks regression model was used to assess the roles of factors on cancer-specific survival (CSS) in both SEER and cases in our center. Results:Multivariate logistic analysis showed that gendere represented an independent risk factor of T 3-T 4 UTUC development( OR=0.86, P=0.02). Kaplan-Meier analysis showed that better OS and CSS for females only existed in the non-muscle invasive stages(5-year OS rates were 80.4% vs.87.3%, χ 2=31.0, P<0.001; 5-year CSS rates were 82.6% vs.89.2%, χ 2=31.2, P<0.001). In multivariate competing-risks regression models, no statistically significant differences in survival were observed between males and females ( HR=0.83, P=0.115). For the patients in our center, there were also no statistically significant differences existed in the non-muscle invasive stage between two genders on OS and CSS ( HR=0.93, P=0.071; HR=0.87, P=0.064). Conclusions:Females were less likely to have advanced pathological T stage. The differences on OS and CSS between males and females only existed in non-muscle invasive stage. However, after accounting for gender related factors, gender no longer had effects on UTUC prognosis.