Conditional probability of survival and post-progression survival in patients with glioblastoma in the temozolomide treatment era

Abstract

With standard treatment for glioblastoma (GBM) consisting of surgery followed by radiotherapy (RT) with concurrent and adjuvant temozolomide (TMZ), median survival is ~14.6 months. This is not as informative to patients who have survived for some time. Conditional probability of survival may offer more relevant survival estimates. Outcomes/conditional probability of survival and post-progression survival (PPS) estimates were retrospectively reviewed in the TMZ treatment era of 882 consecutive patients with a diagnosis of GBM from January 2004 to August 2010. Median age of entire cohort was 62 years including 62 % males. Baseline performance status (PS) was 0-1 in 67, 23 % had frontal lobe tumors, 58 % received concurrent RT/TMZ ± adjuvant TMZ. Survival (OS) was similar for those with frontal lobe tumors versus other locations (P = 0.25). OS for patients receiving standard RT/TMZ ± TMZ was 14.2 months. Age, PS, extent of surgery, therapy post-surgery had significant effects on OS. OS for entire cohort at 1, 2, 3, 4, 5 years was 43.4, 17.9, 10.4, 8.4, 7.2 % respectively. Conditional probability of survival of an additional year given survival to 1, 2, 3, 4, 5 years was 41.4, 58, 80.7, 85.7, 81.5 % respectively. Conditional probability of survival for those patients receiving concurrent RT/TMZ ± adjuvant TMZ was similar. Patients who progress >18 months after their initial treatment for GBM had significantly greater 2 and 5 year PPS as well as OS. Conditional probabilities of survival may provide more meaningful life expectancy predictions for survivors of GBM than conventional survival outcomes.

Tumor treating fields and maintenance temozolomide for newly-diagnosed glioblastoma: a cost-effectiveness study

“…Our model relied on a single pivotal trial for TTFields in newly-diagnosed GBM. Nonetheless, the EF-14 trial was sufficiently powered to detect the proposed study outcomes, and the survival results for the control arm were consistent with a previous study of TMZ for GBM 45 , as well as that reported in the epidemiological literature 7,[20][21][22][23] . We also assumed the age of the patient entering the model was consistent with the EF-14 trial, which was younger than the reported age of GBM patients in real-world populations 2 .…”

“…Of the 541 publications screened, 23 publications were reviewed in full text based on their relevance, as indicated by title and abstract, and seven publications were selected for a detailed review based on the time horizon and suitability of reported results. All seven publications indicated that the probability of surviving GBM increased the longer patients survived since diagnosis, and that the first 2 years after diagnosis were the period of the highest mortality hazard rates 6,7,[20][21][22][23][24] . We excluded four publications based on single institution reports in favor of larger epidemiological populations 6,[22][23][24] .…”

Targeting Glioma Stem Cell-Derived Pericytes Disrupts the Blood-Tumor Barrier and Improves Chemotherapeutic Efficacy

“…Despite a significant advance in cancer treatment, there has been little improvement in the prognosis of GBM patients over decades (Chinot et al, 2014; McNamara et al, 2014). This striking failure could be ascribed to multiple factors, but the blood-tumor barrier (BTB) represents a formidable obstacle.…”

Study on Therapeutic Action and Mechanism of TMZ Combined with RITA Against Glioblastoma

“…However, the treatment of GBM is still a challenge so far. Some groups have indicated that the TMZ is an effective drug to treat GBM, but the survival period remains below 15 months and the recurrence is high [1,7]. Therefore, developing novel treatment methods are very necessary.…”

“…The most effective treatment method for glioblastoma is the maximal safe surgical resection followed by concurrent treatment with TMZ as well as radiation therapy followed by adjuvant TMZ [4][5][6]. Unfortunately, GBM is prone to drug resistance and recurrence after treating with TMZ, and the treatment efficacy is still suboptimal as two-thirds of patients die by 2 years from diagnosis [5] The survival period of the GBM patients with positive treatment remains less than 15 months [7]. Thus, it is essential to discover novel targets or develop effective drugs combination strategy to treat GBM.…”