Radiation therapy for older adults with glioblastoma: radical treatment, palliative treatment, or no treatment at all?

Treatment of Older Adult Patients with Glioblastoma: Moving towards the Inclusion of a Comprehensive Geriatric Assessment for Guiding Management

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults, and over half of patients with newly diagnosed GBM are over the age of 65. Management of glioblastoma in older patients includes maximal safe resection followed by either radiation, chemotherapy, or combined modality treatment. Despite recent advances in the treatment of older patients with GBM, survival is still only approximately 9 months compared to approximately 15 months for the general adult population, suggesting that further research is required to optimize management in the older population. The Comprehensive Geriatric Assessment (CGA) has been shown to have a prognostic and predictive role in the management of older patients with other cancers, and domains of the CGA have demonstrated an association with outcomes in GBM in retrospective studies. Furthermore, the CGA and other geriatric assessment tools are now starting to be prospectively investigated in older GBM populations. This review aims to outline current treatment strategies for older patients with GBM, explore the rationale for inclusion of geriatric assessment in GBM management, and highlight recent data investigating its implementation into practice.

Palliative Radiotherapy of Primary Glioblastoma

BACKGROUND/AIM

Care is often palliative when patients are not fit and complete resection of glioblastomas cannot be achieved. This study aimed to identify predictors of survival after palliative radiotherapy.

PATIENTS AND METHODS

Thirty-one patients irradiated after biopsy or incomplete resection of primary glioblastoma were retrospectively analyzed. Median total dose, dose per fraction and equivalent dose in 2 Gy fractions (EQD2) were 45.0 Gy, 3.0 Gy and 46.0 Gy, respectively. Median number of fractions was 15, median treatment time 3 weeks. Ten patients received temozolomide. Six factors were evaluated for survival including location of glioblastoma, Karnofsky performance score (KPS), gender, age, EQD2 and temozolomide.

RESULTS

KPS ≥60 showed a trend for improved survival (p=0.141). For other factors including EQD2, no significant association with survival was found.

CONCLUSION

Patients with a KPS ≤50 have a poor survival prognosis and appear good candidates for short-course radiotherapy. Selected patients with better KPS may be considered for more aggressive treatments.

A Surveillance, Epidemiology and End Results-Medicare data analysis of elderly patients with glioblastoma multiforme: Treatment patterns, outcomes and cost

The Surveillance, Epidemiology and End Results (SEER) database was used to determine the treatment patterns, outcomes and cost of therapy in elderly patients with glioblastoma multiforme (GBM). The SEER-Medicare linked database was used to identify patients aged >66 years with GBM diagnosed between 1997 and 2009. The patients were stratified by initial treatment following diagnostic surgery (resection or biopsy) into 6 groups as follows: No treatment, standard radiation therapy (SRT) with and without concurrent temozolomide (TMZ), hypofractionated RT (HRT) with and without concurrent TMZ, or TMZ alone. The 3,759 patients identified had a median age of 74 years (range, 66-97 years). A total of ~48% of the patients received SRT without TMZ; ~10% received SRT with concurrent TMZ; ~29% received no treatment; ~10% received HRT without TMZ; ~1% received HRT with TMZ; and <1% received TMZ alone. Untreated patients had a median survival of 2 months (range, 0-89 months). Patients treated with SRT with and without concurrent TMZ had a median survival of 11 and 9 months, respectively (P=0.01). Patients treated with HRT with and without TMZ or TMZ alone had a median survivals of 3 months [adjusted hazard ratio (AHR)=0.48; 95% confidence interval (CI): 0.36-0.66], 4 months (AHR=0.55; 95% CI: 0.49-0.62) and 6 months (AHR=0.43; 95% CI: 0.29-0.62), respectively. The median post-surgery total treatment cost for patients receiving HRT with and without TMZ or TMZ alone was 63,915, 42,834 and 48,298 USD, respectively. Standard RT with concurrent TMZ was associated with improved survival, even in patients aged >75 years. HRT with and without concurrent TMZ and TMZ alone improved survival compared to the no treatment group. Therefore, in certain cases, HRT or TMZ alone may be more cost-effective, with similar survival outcomes. The various treatment options highlight the need for geriatric assessment tools to aid in therapeutic decision making.