Can plasma vitamin C predict survival in stage IV colorectal cancer patients? Results of a prospective cohort study

Sally Temraz; Jana Jabbour; Farah Nassar; Remie El Helou; Ruba Hadla; Maria Mezher; Ahmed El Lakkiss; Maya Charafeddine; Rihab Nasr; Ali Shamseddine

doi:10.3389/fnut.2023.1110405

Can plasma vitamin C predict survival in stage IV colorectal cancer patients? Results of a prospective cohort study

Front Nutr. 2023 Mar 6:10:1110405. doi: 10.3389/fnut.2023.1110405. eCollection 2023.

Authors

Affiliations

¹ Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
² Nutrition Program, Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Beirut, Lebanon.
³ Department of Clinical Nutrition, American University of Beirut Medical Center, Beirut, Lebanon.
⁴ Department of Anatomy, Cell Biology and Physiology, American University of Beirut Medical Center, Beirut, Lebanon.

Abstract

Background and aims: In light of the inconclusive evidence on the association between vitamin C status and colorectal cancer (CRC) outcome, this study assessed the prognostic value of vitamin C in participants with metastatic CRC (mCRC).

Methods: Adults with mCRC and cancer-free controls were recruited in this prospective cohort study to allow for comparison of vitamin C levels with healthy individuals from the same population. Sociodemographic, lifestyle, medical variables, BRAF and KRAS mutations, as well as Vitamin C plasma level and food intake were evaluated. Predictors of diminished vitamin C level were assessed via multivariate logistic regression. Mortality and progression free survival (PFS) among mCRC participants were analyzed based on plasma vitamin C level.

Results: The cancer group (n = 46) was older (mean age: 60 ± 14 vs. 42 ± 9.6, p = 0.047) and included more males (29% vs. 19%, p < 0.001) than the cancer-free group (n = 45). There was a non-significant difference in the vitamin C intake between the two groups; however, the mean plasma vitamin C level was lower in the cancer group (3.5 ± 3.7 vs. 9.2 ± 5.6 mg/l, p < 0.001). After adjusting for age and gender, the cancer group was more likely to be deficient compared to the cancer-free group [Adjusted Odds Ratio (95%CI): 5.4 (2.1-14)]. There was a non-significant trend for higher mortality in the vitamin C deficient cancer group (31% vs. 12%, p = 0.139). PFS did not differ based on vitamin C deficiency and patients with BRAF and KRAS mutations did not have significant differences in vitamin C levels.

Conclusion: mCRC patients have lower plasma vitamin C levels than healthy controls. The trend toward higher mortality in the vitamin C deficient cancer group was not statistically significant. Whether this phenomenon affects survival and response to treatment warrants further exploration in phase III clinical trials.

Keywords: colorectal cancer; mortality; plasma; progression; vitamin C.