What is MGMT methylation status?
The MGMT promoter methylation status, as determined by MSP, is the strongest prognostic factor for outcome in patients with newly diagnosed glioblastoma, and is a powerful predictor of response to alkylating chemotherapy (Table 2).
What does unmethylated tumor mean?
MGMT methylation – This is short for O6-methylguanine-DNA methyltransferase and whether it is ‘methylated’ or ‘unmethylated’ indicates how effectively the tumour cells can repair the damage inflicted on them by certain chemotherapy drugs, such as Temozolomide.
What is MGMT in cancer?
MGMT gene transfer to protect normal cells As MGMT is a potent drug-resistance gene, it has emerged as the favourite target gene for protection of haematopoietic stem cells during chemotherapy for cancer.
How effective is temozolomide on unmethylated glioblastoma?
During the past 15 years, studies have repeatedly demonstrated that it is the 45% to 55% of patients with glioblastoma with at least partial methylation of the O6-methylguanine-DNA methyltransferase promoter (MGMTp) who benefit from the addition of temozolomide to their treatment regimen.
Does MGMT promoter methylation affect survival in tumor tumors?
We determined the MGMT promoter methylation status in tumor tissues from patients who were enrolled in a randomized trial that showed a survival advantage among patients treated with temozolomide and radiotherapy as compared with radiotherapy alone. 16
What is the prognosis of unmethylated MGMT treated with chemoradiotherapy?
On the other hand, cases with unmethylated MGMTtreated with chemoradiotherapy had recurrence free of (78.9, 31.6, and 15.8%) at 1, 2, and 3 years, respectively. This interpretation was quite clear also for the type of chemotherapies used in the treatment of glioblastoma (See Table 4).
Does MGMT methylation affect outcome in patients with Temozolomide-induced methylated MGMT promoters?
Despite the survival benefit associated with temozolomide among patients with a methylated MGMT promoter, the overall survival curves for temozolomide and radiotherapy and for radiotherapy alone remain similar for the first nine months of follow-up. This suggests that MGMT methylation, though important, is not the sole factor determining outcome.
Should TMZ be omitted in unmethylated MGMT with GBM?
While it is well established that TMZ has better efficacy in patients with MGMTpromoter methylation, it remains an area of debate whether TMZ should be omitted when treating GBM patients with unmethylated MGMT. Methods