Background. There are conflicting results on the role of cobalamin and folate for epidemiology and carcinogenesis in colorectal cancer patients and the need of supplementation for prevention of chemotherapy toxicity. Patients and methods. Serum cobalamin, folate, and homocysteine were analysed before and during the treatment of 93 patients with advanced colorectal cancer (ACRC) with first-line chemotherapy treatment. This cohort was compared with a healthy control group of 224 individuals. Results. Patients with ACRC had similar cobalamin, folate, and homocysteine values as the healthy control group. There were no correlations between serum cobalamin, folate, and homocysteine values and objective response. There were no correlations to anaemia or other severe toxicity for cobalamin and homocysteine. A total of 12 patients had folate deficiency, and 10 of those suffered from severe toxicity (grade 3 or more). All patients had markedly increased folate values after 2 months of treatment. Folate and homocysteine did not predict patient outcome; however, patients with subclinically low cobalamin values (<300 pmol/L) had significant better overall survival and time to progression than patients with normal or high cobalamin values. Conclusion. Patients with ACRC seem to have fairly adequate cobalamin and folate status before and during chemotherapy treatment. This study indicates that ACRC patients receiving chemotherapy do not need supplementation with vitamin B12 and folate. A minor portion of the patients had folate deficiency, and most of those patients had severe toxicity. Patients with subclinically low cobalamin values had surprisingly better survival.
Byström, P., Björkegren, K., Larsson, A., Johansson, L., & Berglund, Å. (2009). Serum vitamin B12 and folate status among patients with chemotherapy treatment for advanced colorectal cancer. Upsala Journal of Medical Sciences, 114(3), 160–164. https://doi.org/10.1080/03009730903027172