Putz F, et al. - Researchers, in this study, investigated safety and efficacy of concurrent chemoradiotherapy (CRT) with temozolomide in elderly patients with glioblastoma. They developed a model here that could estimate the probability of successful performance of concurrent CRT with temozolomide in accordance with patient’s age, sex, and pretreatment platelet count. Thus, an identification of a subgroup of elderly glioblastoma patients suitable for chemoradiation with temozolomide could be performed.

Methods

• Researchers performed a retrospective analysis of 74 elderly glioblastoma patients (65 y and above) treated with concurrent CRT with temozolomide.
• They investigated factors influencing prognosis and feasibility of CRT.

Results

• Findings revealed the median overall survival of 11.3 months.
• As per univariate analysis, a significant difference was evident regarding median overall survival for cumulative dose of concurrent temozolomide (optimal cutoff, 2655 mg/m²; 13.9 mo for >2655 mg/m² vs. 4.9 mo for &le 2655 mg/m²; P=0.0216, adjusted for multiple testing).
• Multivariate analysis, in addition, revealed that cumulative dose of concurrent temozolomide >2655 mg/m² was a significant independent prognostic parameter (hazard ratio, 0.33; P=0.002).
• In patients with an insufficient cumulative temozolomide dose, hematotoxicity was the most common cause of treatment interruption or discontinuation.
• For successful performance of CRT with a cumulative dose of concurrent temozolomide >2655 mg/m², prognostic factors included female sex (odds ratio [OR], 0.174; P=0.006), age (OR, 0.826 per year; P=0.017), and pretreatment platelet count (OR, 1.013 per 1000 platelets/μL; P=0.001).
• An online calculator was developed for easy clinical application of the model.