Predictive value of blood lipid association with response to neoadjuvant chemoradiotherapy in colorectal cancer

The aim of this research was to explore whether blood lipid parameters could predict tumor regression grading (TRG) and compare with the predictive value of carcinoembryonic antigen (CEA) in patients with locally advanced colorectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (nCRT). Between June 2011 and January 2015, the records of 176 patients with primary colorectal adenocarcinoma treated with nCRT followed by radical surgery were reviewed retrospectively. Total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and pre-CEA were measured before nCRT, and post-CEA was measured before surgery. A total of 129 (73.3 %) good responders (TRG 3–4) and 47 (26.7 %) poor responders (TRG 0–2) were assessed after the nCRT. TC, LDL, HDL, and ΔCEA were 6.56 ± 0.95, 3.08 ± 0.72, and 1.43 ± 0.25 mmol/L and −0.69 ± 8.33 μg/mL in poor responders compared with 5.15 ± 1.29, 2.39 ± 0.5, and 1.37 ± 0.32 mmol/L and 16.67 ± 30.18 μg/mL in good responders, respectively (p < 0.05). TG, pre-CEA, and post-CEA were not significantly different. Multivariate logistic regression analysis revealed TC and ΔCEA as independent factors in predicting TRG; TC showed a sensitivity of 62.79 %, a specificity of 91.49 %, a Youden index of 0.543, a cutoff value of 5.52, and an AUC of 0.800 compared with ΔCEA (sensitivity 76.74 %, specificity 65.96 %, Youden index 0.427, and AUC 0.761). TC has a better predictive value than ΔCEA and hence might serve as a predictor of TRG in LARC patients.