A Three-Year Retrospective Analysis: Do Nutritional and Immunological Indices Predict Postoperative Complications After Rectal Resection?

Background Nutritional and immunological indices, such as prognostic nutritional index (PNI), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR), have been used as predictors of outcomes and survival in a few cancers. However, the literature is unclear about their usefulness in predicting postoperative complications in rectal cancer resection operations. Additionally, the prescribed cut-off values as well as the timing of the tests for these indices vary among studies. We aimed to determine the role of PNI, NLR, and PLR in predicting postoperative complications in patients undergoing rectal resection. Methods This is a retrospective analysis from a colorectal unit of a tertiary care teaching hospital. All consecutive patients undergoing rectal resection for rectal cancer between April 2018 and March 2021 were included. PNI, NLR, and PLR were calculated from preoperative blood tests, and all morbidity and mortality within 30 days of operation were considered. Results A total of 202 patients were included. Three patients who did not have the necessary preoperative blood test reports were excluded. Of the remaining 199, 142 (71.4 %) were males. The mean age was 47.3 years. Of the patients, 13.6% (n = 27) had major morbidity (Clavien-Dindo grade 3-5), including one mortality. The mean PNI, NLR, and PLR were 49.9, 4.3, and 230.5, respectively. The mean PNI between the groups (no complication vs. complication) was 49.6 vs. 50.1 (p = 0.46) and the mean NLR between the same groups was 4.7 vs. 3.8, (p = 0.06), and both were not significant. The mean PLR between the groups (256.3 vs. 203.4, p = 0.01) was found to be significant but significance was not elicited when only major complications were considered. Hence, none of the indices were a good predictor of postoperative complications in our study. Conclusion The role of nutritional and immunological indices (PNI, NLR, and PLR) is limited in predicting postoperative morbidity in rectal resection operations.