Elderly patients with glioblastoma multiforme--an underestimated subpopulation?

A pilot study of glioblastoma multiforme in elderly patients: treatments, O-6-methylguanine-DNA methyltransferase (MGMT) methylation status and survival

OBJECTIVES

Elderly Glioblastoma multiforme (GBM) patients have a worse prognosis and receive variable treatments. MGMT gene promoter methylation is linked with improved survival in GBM. We examined treatments administered and survival including in relation to MGMT methylation status in elderly GBM patients.

PATIENTS AND METHODS

Patients ≥65 years with diagnosed GBM between 1/01/2007 and 30/04/2009 and undergoing either a biopsy, subtotal (STR) or gross total resection (GTR) were included. The collected information included MGMT status [methylated (ME) vs. unmethylated (UN)] and survival data. p<0.05 was considered significant.

RESULTS

59 patients were identified with median age at diagnosis being 72.68 years (65.72-85.04). Treatment included surgery (25 GTR, 8 STR, 26 biopsy), chemoradiation (22) and radiotherapy alone (20). Overall median overall survival (MOS) was 219 days. MOS with chemoradiation was 316 days vs. 143 days without it (p=0.011). 47 patients had definite MGMT status (28 ME, 19 UN). In ME patients, 9/28 received temozolamide compared to 10/19 in UN category. Temozolamide administration in patients with definite MGMT status was based on WHO performance status (p=0.007). MOS in UN group was 308 days vs. 167 days in ME group (p=0.068). In a multivariate Cox model including use of temozolamide, WHO score and methylation status, only temozolamide use was significantly associated with a reduced risk for death (HR 0.443, 95% CI 0.200-0.982, p=0.045).

CONCLUSIONS

In this small cohort of patients, chemoradiation in suitable elderly GBM patients seemed to afford a survival benefit. MGMT methylation was not associated with an improved survival with temozolamide being the only factor leading to a better survival. Temozolamide use should be considered irrespective of MGMT status in this population with future large prospective studies needed to elucidate this further.

Surgical outcomes for older patients with glioblastoma multiforme: preoperative factors associated with decreased survival. Clinical article

OBJECT

As the population ages, the incidence of glioblastoma multiforme (GBM) among older patients (age > 65 years) will increase. Older patients, unlike their younger counterparts, are not often offered aggressive surgery because of their age, comorbidities, and potential inability to tolerate surgery. The goal of this study was to identify preoperative factors associated with decreased survival for older patients who underwent resection of a GBM. The identification of these factors may provide insight into which patients would benefit most from aggressive surgery.

METHODS

All patients older than 65 years who underwent nonbiopsy resection of an intracranial GBM at a single institution between 1997 and 2007 were retrospectively reviewed. Factors associated with overall survival were assessed using multivariate proportional hazards regression analysis after controlling for peri- and postoperative factors known to be associated with outcome (extent of resection, carmustine wafer implantation, temozolomide chemotherapy, and radiation therapy). Variables with p < 0.05 were considered statistically significant.

RESULTS

A total of 129 patients with an average age of 73 ± 5 years met the inclusion/exclusion criteria. At last follow-up, all 129 patients had died, with a median survival of 7.9 months. The preoperative factors that were independently associated with decreased survival were Karnofsky Performance Scale (KPS) score less than 80 (p = 0.001), chronic obstructive pulmonary disease (p = 0.01), motor deficit (p = 0.01), language deficit (p = 0.005), cognitive deficit (p = 0.02), and tumor size larger than 4 cm (p = 0.002). Patients with 0-1 (Group 1), 2-3 (Group 2), and 4-6 (Group 3) of these factors had statistically different survival times, where the median survival was 9.2, 5.5, and 4.4 months, respectively. In log-rank analysis, the median survival for Group 1 was significantly longer than that for Group 2 (p = 0.004) and Group 3 (p < 0.0001), while Group 2 had longer survival than Group 3 (p = 0.02).

CONCLUSIONS

Older patients with an increasing number of these factors may not benefit as much from aggressive surgery as patients with fewer factors. This may provide insight into identifying which patients older than 65 years of age may benefit from aggressive surgery.