Patterns of failure following stereotactic radiosurgery salvage for recurrent high-grade glioma
摘要
Re-irradiation with stereotactic radiosurgery (SRS) is an increasingly used treatment for recurrent high-grade glioma (HGG). We analyzed the patterns of failure after salvage SRS to better identify which patients would most benefit.
MethodsWe reviewed all patients who received SRS for recurrent HGG over 12 years at our institution. Pattern of failure was defined by the distance of recurrence from the SRS isodose line. Overall-survival (OS), progression-free survival (PFS), and local-failure-free survival (LFS) were estimated using Kaplan-Meier methods, and regression model analysis was performed to analyze clinical predictors of failure.
Results146 patients with HGG underwent SRS treatment to 410 target lesions. The median target volume was 3.3 cm3 and median total dose was 18 Gy. Sixty-one (41.8%) patients developed progression following SRS. PFS at 6 and 12 months were 65.8% and 37.3% respectively. Median OS was 12.4 months from salvage SRS. There were 113 (79.5%) local failures, 2 (1.4%) distant, and 27 (19%) concomitant local and distant failures. LFS at 1 and 2 years was 65.1% and 40.4%, respectively. Non-white race (HR = 0.60), SRS dose ≥ 20 Gy (HR = 0.34), and KPS ≥ 70 (HR = 0.44) were associated with longer time to local failure, and age ≥ 60 years (HR = 2.29) was associated with shorter time to local failure. Non-white race (HR = 5.55) and SRS dose ≥ 20 Gy (HR = 5.62) were associated with more distant failure.
ConclusionThe dominant pattern of failure remains local and in-field despite conformal dose distribution with SRS and infiltrative tumor histology. This supports the role of reirradiation with SRS in well-selected patients with recurrent HGG.