| Summary: | Su-ping Guo,1,2,* Chen Chen,1,2,* Zhi-fan Zeng,1,2 Qiao-xuan Wang,1,2 Wu Jiang,2,3 Yuan-hong Gao,1,2 Hui Chang1,2 1Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, People’s Republic of China; 2State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 3Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yuan-hong Gao; Hui ChangDepartment of Radiation Oncology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, Guangdong, 510060, People’s Republic of ChinaTel +86-13560182168; +86-13480295989Email gaoyh@sysucc.org.cn; changhui@sysucc.org.cnBackground: Serum lipids have been reported as prognosticators for malignancies, including rectal cancer (RC). Yet, their value in predicting the response of RC to neoadjuvant chemoradiotherapy (NACRT) remains unknown. This study aimed to assess the predictive abilities of serum lipids for a bad response, and to build a serum lipid-based prediction model.Methods: In total, 751 patients diagnosed with stage cII–III RC and treated with NACRT plus surgery from January 2007 to August 2018 were retrospectively reviewed and randomly divided into two data sets, in a ratio of 1:1. Receiver operating characteristics (ROC) analysis was conducted in the development set to select possible predictors of bad NACRT response from pathoclinical factors, including serum lipids. Multivariate logistic regression was conducted to further determine independent predictors, which were then used to develop a prediction index (PI). Finally, the PI was verified in the validation set, through ROC analysis and chi-squared test.Results: Five independent predictors were identified: tumor length ≥ 4 cm, cT4 stage, carcinoembryonic antigen ≥ 5.0 ng/mL, irradiation with three-dimensional conformal radiotherapy technique, and apolipoprotein A-I ≤ 1.20 g/L. Each of them was assigned a number of points. In the validation set, the area under the curve of PI appeared as 0.642 (95% confidence interval 0.586– 0.697). The sensitivity, specificity, positive and negative predictive values, and concordance were 72.3%, 52.3%, 63.8%, 61.9%, and 63.0%, respectively.Conclusion: Serum apolipoprotein A-I was found to correlate negatively with the RC response to NACRT. It could serve as a biomarker for guiding individualized treatment and a potential target for improving sensitivity to chemoradiation.Keywords: rectal cancer, radiotherapy, apolipoprotein A-I, tumor response, prediction model
|
|---|
