| Abstract: | Objective To compare the differences in serum Val and Met concentrations in healthy people, patients with benign breast tumors and breast cancer patients, and explore the relationship between serum valine and methionine and the clinical characteristics and risk of breast cancer. Methods The serum Val and Met concentrations of 38 patients with benign breast tumors and 87 patients with breast cancer were determined by liquid chromatography-tandem mass spectrometry, and 91 healthy participants were selected as the control group. The Kruskal-Wallis H-test was used to compare the differences in serum Val and Met concentrations between different groups, and the effects of different chemotherapy regimens and surgical methods on serum Val and Met concentrations in breast cancer patients were analyzed. Binary Logistic regression analysis, calculation of odds ratio and 95% confidence interval （CI） were used to evaluate the relationship between serum Val, Met and breast cancer risk, and ROC curve was drawn to evaluate the diagnostic performance of serum Val and Met for breast cancer. Results Compared with healthy control group, the serum Val concentration in breast cancer （BC） group was higher than that in benign breast tumor （BE） group and healthy control group, and the Met level in BC and BE groups was higher than that in healthy control group, and the differences were statistically significant （P < 0.05）. There were no significant differences in serum Val and Met concentrations among breast cancer patients with different TNM stages and chemotherapy regimens, but there were differences in serum Val concentrations among breast cancer patients with different molecular types. In addition, there was no significant relationship between serum Val concentration level and breast cancer risk, but serum Met significantly affected the occurrence of breast cancer （P < 0.001）. The higher serum Met concentration was, the higher the risk of breast cancer was; and for every one-unit increase in Met levels, the risk of breast cancer increased by 24 percent （OR = 1.24 95%CI: 1.15-1.34）. Serum Met （P < 0.001） was statistically significant in the diagnosis of breast cancer. The AUC was 0.83, the sensitivity and specificity were 69% and 90.1%, respectively, and the critical value was 19.76 μmol/L. Conclusion The serum Val concentration of breast cancer patients was higher than that of benign breast tumor patients and healthy population. Serum Met levels were also elevated in patients with breast cancer and benign breast tumors compared with healthy subjects. There was no significant correlation between serum Val concentration and breast cancer risk, but serum Met was negatively correlated with breast cancer risk, and serum Met had certain diagnostic efficacy for breast cancer diagnosis. |
