Introduction: We examined the effect of postsurgical whole-brain radiotherapy (WBRT) vs. localized radiotherapy (LRT), including both stereotactic radiosurgery and intraoperative radiotherapy, on the rate of recurrence both local and distal to the resection site in the treatment of brain metastases.
Methods: We identified patients who underwent surgery at the Cleveland Clinic for brain metastases between February, 2004 and January, 2012. IRB-approved chart review was conducted and patients who had radiotherapy prior to surgery, non-metastatic lesions, or who lacked post-adjuvant imaging studies were excluded.
Results: The final analysis included 212 patients. Of these, 156 patients received WBRT (including 12 who received concurrent WBRT and SRS as adjuvant), 37 received stereotactic radiosurgery only, and 19 were treated with intraoperative radiotherapy. 146 patients are known to be deceased, of which 60 (41%) died with no evidence of recurrence or progression of their brain disease. Competing risks methodology was used to test the association between adjuvant type and rate of progression. Multivariable analysis found no significant difference in the rate of recurrence at the resection site (HR 1.46, p=.26) or of unresected radiotherapy-treated lesions (HR 1.70, p=.41) for LRT vs. WBRT. There was an increased hazard of development of new lesions (HR 2.41, p<.0001) and of the development of leptomeningeal disease (HR 2.45, p=.04) for patients treated with LRT. Median overall survival was estimated to be 16.5 months and was not found to be significantly different for patients treated with LRT vs. WBRT (HR 0.96, p=.83).
Conclusions: Localized radiotherapy as adjuvant treatment to surgical resection of brain metastases is associated with an increased rate of development of new lesions and leptomeningeal disease when compared to WBRT, but not with recurrence at the resection site or of unresected lesions treated with radiotherapy. There was not a significant difference in overall survival between groups.
Patient Care: Our research helps inform treatment decisions made by providers and patients regarding the choice of adjuvant radiotherapy after surgical resection for brain metastases.
Learning Objectives: By the conclusion of the session, participants should be able to discuss the risks of tumor recurrence for patients treated with adjuvant local vs. whole-brain radiation therapy after surgical resection of brain metastases.