Plasma total homocysteine level in association with folate, pyridoxine, and cobalamin status among Iranian primary breast cancer patients.

Recently the elevated plasma total homocysteine (tHcy) concentration has been concerned as the secondary feature of tumoral proliferation and enhances the likelihood of thrombogenesis in cancer patients. The objective of this study was to determine the associations between folate, cobalamin, and pyridoxine with fasting plasma tHcy concentration in breast cancer (BC) patients. The intake levels of nutrients were assessed using a validated food frequency questionnaire in 141 newly diagnosed BC patients. The plasma tHcy and pyridoxal-5-phosphate were measured using high performance liquid chromatography with fluorescence detector. Plasma tHcy levels were observed to be significantly higher among BC participants with Stage III where the plasma concentrations of folate was also comparatively less (P < 0.05) than other stages. Dietary pyridoxine was even being consumed less at this stage (P < 0.05). The plasma, dietary, and residual variables of folate were inversely correlated with plasma tHcy concentration (P < 0.05). Dietary cobalamin was also associated negatively with tHcy (P < 0.05). The odds ratio of comparing the highest tertile of plasma cobalamin (>394 pmol/l) and folate (>11.4 ng/ml) vs. the lowest categories were associated with reduced odds of high tHcy occurrence with 0.20 (95% confidence interval: 0.04-0.98) and 0.14 (95% confidence interval: 0.03-0.64), respectively. In conclusion, nutrition-related methyl-group insufficiency could lead to imbalance in tHcy metabolism, as a possible cancer marker.