身體質量指數對不同治療之肌肉侵犯性膀胱癌預後價值：單一醫學中心回溯性研究

謝佳駤¹、曾文歆^1,2、黃冠華¹、李健逢³、邱文祥⁴

台南永康奇美醫院 外科部 泌尿科¹；國立中山大學生物醫學研究所²；台南永康奇美醫院 病理部³；台北馬偕醫院 泌尿科⁴

The Prognostic Value of Body Mass Index for Muscle Invasive Bladder Cancer with Different Treatment: A Single-Center Retrospective Study

Chia-Chih Hsieh¹、Wen-Hsin Tseng^1,2、Steven K. Huang¹、Chien-Feng Li³、Allen W.Chiu⁴

¹Division of Urology, Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan;

²Institute of Biomedical Science, National Sun Yat-Sen University, Kaohsiung, Taiwan;

³Department of Pathology, Chi Mei Medical Center, Tainan, Taiwan;

⁴Department of Urology, Mackay Memorial Hospital, Taipei, Taiwan.

Purpose:

Radical cystectomy (RC) and bladder-sparing tri-modal therapy (TMT) are two broad categories of primary definitive treatment for muscle invasive bladder cancer (MIBC). Similar outcomes and efficacy rates have been reported for RC and TMT. Body mass index (BMI) has been proposed as a biomarker for cancer prognosis. The aim of this study was to investigate the prognostic value of the BMI in patients with MIBC and the potential for validation of its role in the selection of appropriate treatment.

Material and Methods:

We retrospectively analyzed 207 patients who were pathologically diagnosed with muscle invasive bladder cancer at the Chi Mei Medical Center between January 2012 and December 2018. We excluded patients with metastasis disease, those who received other treatments, who were lost to follow-up, and lacked pre-operative data. BMI was categorized into two groups, non-overweight (<23 kg/m²) and overweight (≥23 kg/m²), according to the conventional WHO classification. In total, 119 patients who received RC or TMT were enrolled and grouped according to above BMI definitions. The outcomes of interest included disease-free survival (DFS) and overall survival (OS) rates.

Results:

The study comprised 88 men and 31 women (mean age, 67.85 ± 10.98 years). The population was divided into two groups, non-overweight and overweight. In total, 68 (57.1%) patients had BMI≥23 kg/m² and 51 (42.9%) patients had BMI<23 kg/m². On comparing of recurrence rate between two groups, overweight group had less recurrence rate but no significantly difference was noted (non-overweight: 50.9% vs overweight: 35.3%, p=0.086). The average length of time to disease recurrence also showed no different (non-overweight: 21.5 months vs overweight:23.1 months, p=0.813). However, overweight group had better overall survival with significantly different (non-overweight: 35.3% vs overweight: 55.9%, p=0.026). In addition, RC for overweight group had both less recurrence rate (RC: 21.6% vs TMT: 51.6%, p=0.01) and mortality rate (RC: 32.4% vs TMT: 58.1%, p=0.034) when compared with TMT.

Conclusions:

This study demonstrated the relevance of the BMI in the prediction of mortality rate. We could confirm an association with better DFS in the BMI overweight group receiving radical cystectomy. Thus, the diagnosed of overweight in MIBC patients had relatively better prognosis.