Temozolomide chemotherapy based on MGMT protein expression for patients with malignant gliomas:a report of 40 cases

Abstract

Objective This study was to evaluate the efficacy and toxicity of temozolomide(TMZ)chemotherapy based on O6-methylguanine-DNA methyltransferase (MGMT) protein expression in patients with malignant gliomas.Methods A total of 40 patients with pathologically confirmed malignant gliomas were enrolled.All patients had pretreated with radiotherapy and had assessable lesions.MGMT protein expression were detected by immunohistochemical technique.Alternative schedules of TMZ were administered based on MGMT protein expression.Patients with MGMT negtive expression received 150～200 mg/m2 TMZ on days 1-5.Patients with MGMT postive expression received 75 mg/m2 TMZ on days 1-21 or 150～200 mg/m2 TMZ on days 2-6 combined with Cisplatin (DDP) 40 mg/m2 on days 1-2.Results Among 22 patients with MGMT negative expression and 18 patients with MGMT positive expression,the response rate was 31.8％ and 33.3％ (P ＞0.05 ),the median progression-free survival time was 7 months (95％ CI:5.7-8.3) and 7 months(95％ CI:2.3-11.7 ),the median survival time was 24 months(95％ CI:12.7-35.3) and 11.5 months (95％ CI:9.9-11.3 ),respectively.There were no significant differences (P>0.05 ).The most common toxicities were grade Ⅰ～Ⅱ neutropenia (20％ ),decreased appetite (30％ ),nausea and vomitting (22％ )and elevated liver enzymes (25％ ).Conclusion Alternative schedules of TMZ may improve efficacy in patients with MGMT positive expression tumors,toxicities were tolerable. Key words: Gliomas; Chemotherapy; Temozolomide; MGMT