Aims: To investigate the value of previously described pretreatment hematological and biochemical biomarkers as predictors of pathological response. Methods: The authors performed a retrospective analysis of 191 patients with locally advanced rectal cancer who underwent long-course neoadjuvant chemoradiotherapy at two Portuguese centers. The authors performed logistic regression analysis to search for predictive markers of pathological complete and good response. Results: High platelet-neutrophil index (p = 0.042) and clinical tumor stage >2 (p = 0.015) were predictive of poor response. None of the analyzed biomarkers predicted pathological complete response in this study. Conclusion: A high platelet-neutrophil index before neoadjuvant chemoradiotherapy could help predict poorer pathological response in patients with locally advanced rectal cancer. However, no other blood biomarker predicted incomplete or poor response in this study.
Keywords: carcinoembryonic antigen; lymphocyte-to-monocyte ratio; neoadjuvant chemoradiotherapy; neutrophil-to-lymphocyte ratio; pathological response; personalized medicine; platelet-to-lymphocyte ratio; platelet–neutrophil index; predictor; prognostic nutritional index; rectal cancer; systemic immune–inflammation index.