Upper urinary tract urothelial carcinoma (UTUC) is a rare malignancy, particularly in the ureter, and is associated with high rates of recurrence and metastasis. Although body mass index (BMI) has been associated with prognosis in multiple cancer types, its role as a predictive factor in UTUC is still debated. This study aimed to investigate how BMI influences survival outcomes in patients with UTUC treated with radical nephroureterectomy (RNU).
This multi-center retrospective analysis by the Taiwan UTUC Collaboration Group involved 2503 patients who underwent treatment across 19 hospitals from 1988 to 2022. Patients were categorized into normal (18.5 ≤ BMI < 24), overweight (24 ≤ BMI < 27), and obese (BMI ≥ 27) groups. Demographic, clinical, and pathological data were analyzed. Overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), and intravesical recurrence-free survival (IVRFS) were assessed using Kaplan-Meier analysis and Cox proportional hazards models.
The median follow-up period was 44.2 months. In multivariable analysis, overweight patients demonstrated significantly better OS compared with normal-weight patients (p = 0.033), and the obesity group showed a favorable, though not statistically significant, trend toward better OS. However, BMI was not an independent predictor of CSS, DFS, or IVRFS. Independent predictors of worse outcomes included older age, end-stage renal disease, ureteral tumor location, tumor size ≥3 cm, and high-grade urothelial carcinoma. Tumor stage and grade were comparable across BMI groups.
Overweight status was associated with better OS in patients with UTUC treated with RNU, while BMI had no significant impact on CSS, DFS, or IVRFS. These findings suggest a potential protective effect of higher BMI on OS, warranting further investigation in prospective studies. However, BMI alone should not guide clinical decisions and may instead reflect broader patient health characteristics.
The Canadian journal of urology. 2026 Apr 15*** epublish ***
Shu-Yu Wu, Ching-Chia Li, Wen-Jeng Wu, Kuan-Hua Huang, Chien-Liang Liu, Shian-Shiang Wang, Jian-Ri Li, Han-Yu Weng, Ta-Yao Tai, Pi-Che Chen, Ian-Seng Cheong, Chung-You Tsai, Pai-Yu Cheng, Jian-Hua Hong, Chung-Hsin Chen, Jen-Shu Tseng, Wun-Rong Lin, Yuan-Hong Jiang, Yu-Khun Lee, Po-Hung Lin, See-Tong Pang, Yung-Tai Chen, Wei-Chieh Chen, Chia-Chang Wu, Thomas Y Hsueh, Hsu-Che Huang, Wei-Yu Lin, Chia-Cheng Yu, Jen-Kai Fang, Chih-Chin Yu, Yao-Chou Tsai
Department of Urology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, 231, Taiwan., Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung, 807, Taiwan., Division of Urology, Department of Surgery, Chi Mei Medical Center, Tainan, 710, Taiwan., Division of Urology, Division of Urological Oncology, Department of Surgery, Chi-Mei Medical Center, Tainan, 710, Taiwan., Division of Urology, Department of Surgery, Taichung Veterans General Hospital, Taichung, 407, Taiwan., Department of Urology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, 704, Taiwan., Department of Urology, Ditmanson Medical Foundation Chiayi Christian Hospital, Chiayi, 600, Taiwan., Division of Urology, Department of Surgery, Far Eastern Memorial Hospital, New Taipei City, 220, Taiwan., Institute of Biomedical Engineering, National Taiwan University, Taipei, 106, Taiwan., Department of Urology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, 100, Taiwan., Department of Urology, MacKay Memorial Hospital, Taipei, 104, Taiwan., Department of Urology, School of Medicine, Tzu Chi University, Hualien, 970, Taiwan., Division of Urology, Department of Surgery, Chang Gung Memorial Hospital at Linkou, Taoyuan, 333, Taiwan., Department of Urology, Taiwan Adventist Hospital, Taipei, 105, Taiwan., Department of Urology, Taipei Medical University Hospital, Taipei Medical University, Taipei, 110, Taiwan., Department of Urology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, 235, Taiwan., Division of Urology, Department of Surgery, Taipei City Hospital, Taipei, 103, Taiwan., Division of Urology, Department of Surgery, Cardinal Tien Hospital, New Taipei City, 231, Taiwan., Division of Urology, Department of Surgery, Chang Gung Memorial Hospital, Chiayi, 613, Taiwan., Division of Urology, Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, 813, Taiwan., Department of Urology, China Medical University Hospital, Taichung, 404, Taiwan.