Prognostic value of pre-operative mean corpuscular volume (MCV) in colorectal cancer.

Background: Mean corpuscular volume (MCV) has been shown to have some correlation to oncological outcomes in oesophageal cancer, with high pre-operative MCV associated with disease recurrence. A similar association has previously been reported in colorectal cancer.

Aims: This study is aimed at investigating whether high MCV bears similar relation to post-operative outcome and disease recurrence in colorectal cancer (CRC).

Methods: Patients undergoing elective CRC resection with curative intent between January 2008 and December 2019 were identified from our prospective database. Review of patient demographic details, American Society of Anaesthesiologists (ASA) grade, smoking and alcohol intake were performed. In addition, tumour location and staging, operation performed, pre-operative laboratory data and oncological management of each patient were noted. Post-operative morbidity (Clavien-Dindo (CD) score > 2), 30-day mortality, in-hospital mortality and cancer recurrence were examined and multivariable regression analysis was performed to predict these outcomes.

Results: A total of 1,293 CRCs were resected, with 1,159 patients (89.7%) experiencing a hospital course without major morbidity (CD < 3). 30-day mortality rate was less than 1% (12/1293). There were 176 patients (13.6%) with recurrence at follow-up. When multivariable regression analysis was performed, high pre-operative MCV did not predict negative post-operative or oncological outcomes.

Conclusion: MCV does not appear to be an independent prognostic factor for outcomes following elective CRC resection.