This study by Blank et al (2014) examined the role of MTHFR C677T & A1298C mutations and their effect on the treatment of gastric or oesophageal cancer due to their influence on folate metabolism and the drugs that impact upon it e.g. 5-flourouracil. 569 patients with either oesophageal or gastric cancer undergoing chemotherapy were screened for the presence of either C677T & A1298C mutations to discover associations with prognosis, response and clinicopathological factors.
Results showed only the A1298C mutation was found to impact negatively on patient prognosis, but it did not predict the response to chemotherapy. The AC genotype was a significant negative prognostic factor in patients with gastric cancer, and was significantly associated with worse outcomes. The MTHFR C677T was not said to play a role in either positively or negatively influencing either form of cancer, although patients with the CC genoptype were shown to have a shorter survival period by almost 30 months.