Prognostic significance of prognostic nutritional index and hemoglobin to red cell distribution width ratio in metastatic colorectal cancer patients

Aims: Malnutrition and systemic inflammation are poor prognostic factors in cancer. Prognostic nutritional index (PNI) and Hemoglobin to red blood cell distribution witdh (HRR) are considered indicators of malnutrition and systemic inflammation. We aimed to investigate the prognostic importance of PNI and HRR on metastatic colorectal cancer survival. Methods: We retrospectively reviewed all patients diagnosed with metastatic colorectal cancer treated at Kayseri City Training and Research Hospital and Erciyes University Medical School. PNI is calculated as (serum albumin (g/L) +5 x total lymphocyte count (10⁹/L)). And HRR was calculated as the ratio of hemoglobin (g/dl) and RDW (%). PNI was divided into two groups based on the cut off points 46.175 as PNI high and low. And we compared these two groups according to general characteristics and overall survival. We performed another comparision between HRR low and high groups based on the cut off points 0.8675 according to general characteristics and overall survival. Kaplan Meier method was used to analyse overall survival and compared survival rates with the log-rank test. Results: We reviewed 346 metastatic colorectal cancer patients and we included 145 of them who fit to inclusion criteria to the study. Univariate analysis revealed that presence of initially metastatic disease, right located tumor, low HRR, low PNI were independent prognostic markers of poor overall survival. In multivariate analysis, presence of initially metastatic disease and low PNI remain statistically significant independent prognostic markers of poor survival. The median overall survival was statistically longer in HRR and PNI low groups than high groups. Conclusion: Both PNI and HRR are associated with poor overall survival in metastatic colorectal cancer.