Influence of MTHFR C677T Polymorphism on High-Dose Methotrexate-Related Toxicity in Patients With Primary Central Nervous System Diffuse Large B-Cell Lymphoma.

Chang, Xiaoli; Guo, Yixian; Su, Li; Zhang, Yunxiu; Hui, Wuhan; Zhao, Hong; Hu, Ronghua; Sun, Wanling

BACKGROUND Primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL) is a relatively rare and aggressive neoplasm. High-dose methotrexate (HD-MTX) is an effective regimen for the treatment of PCNS-DLBCL, but MTX-related toxicity remains a problem. The aim of this analysis study was to investigate the influence of the methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism on HD-MTX-related toxicity in patients with PCNS-DLBCL. MATERIAL/METHODS A prospective, observational study was conducted to analyze 148 MTX courses in 32 patients with PCNS-DLBCL. RESULTS The delayed MTX clearance was observed in 53 cycles (35.8%). The patients carrying the homozygous variant genotype had a higher risk of developing nephrotoxicity than those carrying the wild-type genotype (odds ratio [OR] 13.08; 95% confidence interval [CI], 1.65-103.86; P = .002) or heterozygous variant genotype (OR 8.43; 95% CI, 2.31-30.70; P < .001). Significant differences were observed in hepatotoxicity (OR 9.33; 95% CI, 2.54-34.27; P < .001) and hematologic toxicity (OR 3.09; 95% CI, 1.18-8.07; P = .024) in addition to nephrotoxicity between the homozygous variant genotype and the wild-type genotype. CONCLUSION The homozygous mutation of C to T at nucleotide 677 increases the risk on HD-MTX-related toxicity. The MTHFR C677T polymorphism can be used to predict HD-MTX-related toxicity for patients with PCNS-DLBCL.