Predictive value of red blood cell distribution width and hematocrit for short-term outcomes and prognosis in colorectal cancer patients undergoing radical surgery.

Background: Previous studies have reported that low hematocrit levels indicate poor survival in patients with ovarian cancer and cervical cancer, the prognostic value of hematocrit for colorectal cancer (CRC) patients has not been determined. The prognostic value of red blood cell distribution width (RDW) for CRC patients was controversial.

Aim: To investigate the impact of RDW and hematocrit on the short-term outcomes and long-term prognosis of CRC patients who underwent radical surgery.

Methods: Patients who were diagnosed with CRC and underwent radical CRC resection between January 2011 and January 2020 at a single clinical center were included. The short-term outcomes, overall survival (OS) and disease-free survival (DFS) were compared among the different groups. Cox analysis was also conducted to identify independent risk factors for OS and DFS.

Results: There were 4258 CRC patients who underwent radical surgery included in our study. A total of 1573 patients were in the lower RDW group and 2685 patients were in the higher RDW group. There were 2166 and 2092 patients in the higher hematocrit group and lower hematocrit group, respectively. Patients in the higher RDW group had more intraoperative blood loss ( < 0.01) and more overall complications ( < 0.01) than did those in the lower RDW group. Similarly, patients in the lower hematocrit group had more intraoperative blood loss ( = 0.012), longer hospital stay ( = 0.016) and overall complications ( < 0.01) than did those in the higher hematocrit group. The higher RDW group had a worse OS and DFS than did the lower RDW group for tumor node metastasis (TNM) stage I (OS, < 0.05; DFS, = 0.001) and stage II (OS, = 0.004; DFS, = 0.01) than the lower RDW group; the lower hematocrit group had worse OS and DFS for TNM stage II (OS, < 0.05; DFS, = 0.001) and stage III (OS, = 0.001; DFS, = 0.001) than did the higher hematocrit group. Preoperative hematocrit was an independent risk factor for OS [ = 0.017, hazard ratio (HR) = 1.256, 95% confidence interval (CI): 1.041-1.515] and DFS ( = 0.035, HR = 1.194, 95%CI: 1.013-1.408).

Conclusion: A higher preoperative RDW and lower hematocrit were associated with more postoperative complications. However, only hematocrit was an independent risk factor for OS and DFS in CRC patients who underwent radical surgery, while RDW was not.