Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios as predictive and prognostic markers in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation.

758Background: A standard therapy for locally advanced rectal cancer (LARC) includes fluoropyrimidine (FP)-based neoadjuvant chemoradiation (nCRT). Previous studies have inconsistently demonstrated that baseline neutrophil- and platelet-to-lymphocyte ratios (NLR and PLR) are predictive of response to nCRT or prognostic of outcomes in LARC. Methods: We performed a review of patients with LARC undergoing nCRT followed by surgery with curative intent from 2005-2013 in 3 academic cancer centers from 2 Canadian provinces. Data regarding demographics, staging, baseline hematologic variables (<4 weeks prior/up to 2 weeks after initiating nCRT) and treatment details were collected. Outcome measures of interest were pathological complete response (pCR), disease-free survival (DFS) and overall survival (OS). Logistic regression and Cox proportional hazard models were used to assess for an association between baseline hematologic variables and outcomes. Results: Of 1081 identified patients, 845 were included in the ...