To evaluate whether any association exists between peripheral blood cell-based inflammatory biomarkers obtained before adjuvant chemoradiotherapy and adverse events (AEs) and survival of patients with pathological stage Ⅱ/Ⅲ rectal cancer treated by adjuvant chemoradiotherapy.

A total of 109 rectal cancer patients were included. The prognostic abilities of neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), lymphocyte to monocyte ratio (LMR) and neutrophil to albumin ratio (NAR) for overall survival (OS) were calculated by the receiver operating characteristic (ROC) curves.

NAR was associated with the occurrence of grade ≥2 leukopenia (OR=4.442, 95% CI: 1.216-16.221, P<0.05). The 5-year OS rates of patients with NAR ≥ 0.055 and patients with NAR<0.055 were 68.2% and 83.9%, respectively (P>0.05). The 5-year disease-free survival (DFS) rates of patients with NAR ≥ 0.055 and patients with NAR<0.055 were 59.1% and 76.8%, respectively (χ²=3.887, P<0.05). Multivariate analysis by Cox proportional-hazards model showed that NAR was significantly associated with OS (HR=3.035, 95% CI: 1.021-9.019, P<0.05).

These results suggest that NAR obtained before adjuvant chemoradiotherapy might serve as an independent biomarker for predicting AEs and prognosis in rectal cancer treated with adjuvant chemoradiotherapy.

Rectal cancer; Neutrophil to albumin ratio; Chemoradiotherapy; Acute adverse event; Survival