Prognostic value of red cell distribution width (RDW) in colorectal cancer. Results from a single-center cohort on 591 patients

Increasing evidence advocates the prognostic role of RDW in various tumours. We analysed 591 patients to assess whether RDW is a prognostic factor for overall (OS) and cancer-related survival (CRS) for patients with colorectal cancer (CRC). The data were retrieved from a retrospective database. The optimal cut-off value for RDW was set at 14.1%; accordingly, two groups were considered: those with a value equal or lower than 14.1% (L-RDW), and those with a value higher than 14.1% (H-RDW). The mean value of RDW rose from pT1 to pT4 tumours. H-RDW correlated with age above the mean, colonic location of the lesion, pT and TNM stage. Finally, H-RDW was significantly associated with the intent of surgery: almost 50% of patients who underwent a non-curative resection presented H-RDW, compared to 19.3% in R0 resections. OS was significantly lower in patients with H-RDW. CRS was similar in the two groups. Stratifying patients according to TNM stage worse OS was associated with H-RDW only in early stages, whereas there was no difference for stages II-IV. Multivariate analysis confirmed that H-RDW was not an independent prognostic factor. Although H-RDW correlated with some negative clinical-pathological factors, it did not seem to independently influence OS and CRS.