The optimal second-line systemic anti-cancer therapy (SACT) for recurrent inoperable glioblastoma (GBM) is not known. Generally, patients with a recurrence within 6 months of adjuvant temozolomide (TMZ) are treated with procarbazine/lomustine/vincristine (PCV) regimen and those with a recurrence at least 6 months after completion of TMZ are re-challenged with TMZ (rTMZ). The aim of this study is to evaluate the clinical outcomes of this individualized approach.
We treated 46 patients with second-line SACT for recurrent GB between 2009 and 2015. The Response Assessment in Neuro-Oncology (RANO) criteria were used to assess treatment response. The Kaplan-Meier method was used to calculate survival. Patient- and disease-related characteristics between the groups were compared using the Fisher exact test.
31 patients received PCV and 15 patients received rTMZ (Table). The median progression-free (PFS) (3.4 months each) and overall survival (OS) (5.2 months vs. 5.3 months p = 0.482) from the start of second-line SACT were similar for both groups. Compared with the PCV group, the median PFS (19.6 months vs. 8.7 months, p = 0.001) and OS (28 months vs. 13.7 months, p = 0.001) calculated from the date of diagnosis were better for the rTMZ group. Toxicity was acceptable in both treatment groups.Table:
|Median age (years)||57 (range 29-71)||63 (range 34-80)||0.119|
|Radical RT alone||2(6.5%)||1(6.7%)|
|Adjuvant treatment completed within 6 months||1 (3%)||11 (73%)||0.001|
|Median time to progression after first-line (months)||1.2 (range: 0.7-11.03)||9.8 (range: 1-24.3)||0.001|
As the individualized approach of second-line SACT in recurrent GB leads to similar survival. Patients who recur more than 6 months after completion of primary chemo-radiotherapy generally have a better survival.
Clinical trial identification
Legal entity responsible for the study
Department of Radiation Oncology, Norfolk & Norwich University NHS Foundation Trust
All authors have declared no conflicts of interest.