Echo-Planar MR Spectroscopic Imaging Pre and Post Radiation Therapy in Patients With High Grade Glioma

Twenty-three tumors had a gross total resection (GTR) alone, 13 had a GTR followed by adjuvant RT (GTR + RT), 5 had a subtotal resection (STR) alone, and 8 had STR and adjuvant RT (STR + RT). The median RT dose was 54 Gy (range 54-60) for atypical and 60 Gy (range 54-60) for anaplastic histology, typically prescribed to the cavity or enhancement with a 0.7-1.5 cm expansion for atypical tumors and 3-4 cm for malignant histology. Patients who recurred were treated with salvage therapy (re-resection, RT, or both). Failure after salvage and the number of salvage treatments were identified. Results: With a median follow-up time of 2.9 years, 18 of 49 patients recurred. Table 1 presents the recurrence, overall survival (OS), and salvage data based on surgery and RT characteristics and compares the sub-groups. Notably, there were significantly fewer failures after salvage and fewer salvage procedures in the GTR+RT group than the GTR alone group (PZ0.027 and 0.019, respectively) Conclusion: These retrospective data report outcomes for patients treated with surgery with and without adjuvant RT and provide some insight regarding salvage for patients who progress. While this study is underpowered to make statistical comparisons regarding initial failure rates, these data suggest that adjuvant fractionated RT following resection of AM reduces local recurrence and subsequent salvage procedures for patients who had a GTR. The RTOG is currently developing a clinical trial to investigate this question in a prospective multi-institutional fashion. Author Disclosure: R.V. Hymas: None. M.A. Taquee: None. I.S. Grills: None. P.Y. Chen: None. D.J. Krauss: None. K. Marvin: None. H. Ye: None. J.T. Dilworth: None.