Purpose: The prognostic value of obesity in patients with renal cell carcinoma (RCC) remains controversial. This study aimed to assess the sex-dependent prognostic role of body mass index (BMI) in patients with nonmetastatic RCC who underwent radical or partial nephrectomy. Patients and methods: We retrospectively analyzed 643 consecutive patients with nonmetastatic RCC who underwent curative nephrectomy in our center between 2004 and 2014. Associations among BMI, sex, overall survival (OS), cancer-specific survival (CSS), and metastasis-free survival (MFS) were analyzed. Results: Males were more likely to have a higher BMI than females (BMI as a categorical variable: P<0.001; BMI as a continuous variable: P=0.002). In men, a high BMI was significantly correlated with better 5-year OS, CSS, and MFS rates (P=0.001, 0.014, and 0.001, respectively), and multivariate analysis identified that a high BMI was independently associated with greater OS, CSS, and MFS (OS: hazard ratio [HR]=0.207, P=0.011; CSS: HR=0.225, P=0.005; MFS: HR=0.243, P=0.004). However, in women, there was no significant difference in 5-year OS, CSS, and MFS rates according to BMI (P=0.781, 0.812, and 0.538, respectively). Moreover, a high BMI was no longer independently associated with OS, CSS, or MFS (P=0.821, 0.832, and 0.801, respectively). Among patients with clear cell RCC, BMI was significantly associated with OS, CSS, and MFS only among men (all P<0.05) and not among women (all P>0.05). Conclusion: Among patients with nonmetastatic RCC, a high BMI was a favorable prognostic factor in males rather than females. Therefore, sex might influence the correlation between obesity and urological outcomes in nonmetastatic RCC.
Cancer management and research. 2019 May 01*** epublish ***
Yangqin Zheng, Lianmin Bao, Jingfeng Chen, Yue Pan, Qinquan Wang, Lianguo Chen, Xiaomin Gao
Department of Hematology, The Third Clinical Institute Affiliated to Wenzhou Medical University, People's Hospital of Wenzhou, Wenzhou, Zhejiang 325006, People's Republic of China., Department of Respiratory, Rui'an People's Hospital, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325200, People's Republic of China., Department of Anorectal Surgery, The Sixth Affiliated Hospital of Wenzhou Medical University, Lishui People's Hospital, Lishui, Zhejiang 323000, People's Republic of China., Department of Urology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325006, People's Republic of China., Department of Clinical Pharmacy, Wenzhou People's Hospital & The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, Zhejiang 325000, People's Republic of China., Department of Urology, Changhai Hospital, Second Military Medical University, Shanghai 200433, People's Republic of China.