Song Nan, Huang Dan, Jang Doeun, Kim Min Jung, Jeong Seung-Yong, Shin Aesun, Park Ji Won
Cancer Research Institute, Seoul National University, Seoul 03080, Korea.
Department of Epidemiology and Cancer Control, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
Cancers (Basel). 2020 Mar 30;12(4):830. doi: 10.3390/cancers12040830.
The optimal body mass index (BMI) range for predicting survival in Asian colorectal cancer patients is unknown. We established the most appropriate cut-off point of BMI to predict better survival in Asian colorectal cancer patients using a two-stage approach. Two cohorts of colorectal cancer patients were included in this study: 5815 hospital-based development cohort and 54,043 nationwide validation cohort. To determine the optimal BMI cut-off point at diagnosis, the method of Contal and O'Quigley was used. We evaluated the association between BMI and overall survival (OS) using the Cox proportional hazard model. During a median follow-up of 5.7 and 5.1 years for the development and the validation cohort, 1180 (20.3%) and 10,244 (19.0%) deaths occurred, respectively. The optimal cut-off of BMI identified as 20.2 kg/m ( < 8.0 × 10) for differentiating between poorer and better OS in the development cohort. When compared to the patients with a BMI < 20.2 kg/m, the patients with a BMI ≥ 20.2 kg/m had a significantly better OS (HR = 0.62, 95% CI = 0.54-0.72, = 1.1 × 10). The association was validated in the nationwide cohort, showing better OS in patients with a BMI ≥ 20.2 kg/m (HR = 0.64, 95% CI = 0.60-0.67, < 0.01). We suggest the use of a BMI value of 20.2 kg/m to predict survival in Asian colorectal cancer patients.
预测亚洲结直肠癌患者生存率的最佳体重指数（BMI）范围尚不清楚。我们采用两阶段方法确定了BMI的最合适切点，以预测亚洲结直肠癌患者更好的生存率。本研究纳入了两组结直肠癌患者队列：5815例基于医院的发展队列和54043例全国范围的验证队列。为了确定诊断时的最佳BMI切点，使用了Contal和O'Quigley方法。我们使用Cox比例风险模型评估了BMI与总生存期（OS）之间的关联。在发展队列和验证队列分别进行的5.7年和5.1年的中位随访期间，分别发生了1180例（20.3%）和10244例（19.0%）死亡。在发展队列中，确定的用于区分较差和较好OS的BMI最佳切点为20.2kg/m²（<8.0×10）。与BMI<20.2kg/m²的患者相比，BMI≥20.2kg/m²的患者OS明显更好（HR=0.62，95%CI=0.54-0.72，P=1.1×10）。该关联在全国队列中得到验证，显示BMI≥20.2kg/m²的患者OS更好（HR=0.64，95%CI=0.60-0.67，P<0.01）。我们建议使用20.2kg/m²的BMI值来预测亚洲结直肠癌患者的生存率。
