title: The incidence of radiation necrosis following stereotactic radiotherapy for melanoma brain metastases: the potential impact of immunotherapy.
abstract: Stereotactic radiotherapy (SRT) is the standard treatment for patients with limited number of brain metastases. In the past few years, newer immunotherapies (immune checkpoint inhibitors) have been proven to prolong survival in patients with metastatic melanoma. The safety of the combination of SRT and immunotherapy for brain metastases is unknown. We retrospectively identified patients with melanoma brain metastases treated with SRT between 2007 and 2015. Patients who did not have at least 3 months of follow-up with imaging after SRT were excluded from the analysis. Outcomes were compared between patients who were treated with or without immunotherapy. A total of 58 patients were included; of these, 29 were treated with SRT and immunotherapy. MAPK inhibitors (BRAF, MEK inhibitors) were used more often in the immunotherapy group (nine vs. two patients). There was a higher incidence of intracranial complications in patients treated with immunotherapy and SRT. Eight patients had radiation necrosis; all occurred in patients who were treated with immunotherapy. Nine patients had hemorrhage, of which seven occurred in patients who were treated with immunotherapy (P=0.08). However, patients treated with immunotherapy and SRT had a significant overall survival advantage compared with SRT without immunotherapy (15 vs. 6 months, P=0.0013). Patients treated with SRT and immunotherapy have a higher incidence/risk of intracranial complications, but a longer overall survival.
authors.affiliation: aUNC Lineberger Comprehensive Cancer Center Departments of bRadiation Oncology cMedicine dNeurosurgery, University of North Carolina, Chapel Hill, North Carolina, USA.
authors.forename: Orit
authors.initials: O
authors.lastname: Kaidar-Person
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Zagar
authors.forename: Allison
authors.initials: A
authors.lastname: Deal
authors.forename: Stergios J
authors.initials: SJ
authors.lastname: Moschos
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Ewend
authors.forename: Deanna
authors.initials: D
authors.lastname: Sasaki-Adams
authors.forename: Carrie B
authors.initials: CB
authors.lastname: Lee
authors.forename: Frances A
authors.initials: FA
authors.lastname: Collichio
authors.forename: David
authors.initials: D
authors.lastname: Fried
authors.forename: Lawrence B
authors.initials: LB
authors.lastname: Marks
authors.forename: Bhishamjit S
authors.initials: BS
authors.lastname: Chera
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D001921:Brain / Q000473:pathology* / Q000528:radiation effects; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy / Q000556:secondary* / Q000628:therapy*; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007167:Immunotherapy / Q000009:adverse effects / Q000379:methods*; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy / Q000628:therapy*; D008875:Middle Aged; D009336:Necrosis; D011832:Radiation Injuries / Q000209:etiology*; D011880:Radiotherapy Planning, Computer-Assisted; D012189:Retrospective Studies; D013238:Stereotaxic Techniques
chemical_list: D000911:Antibodies, Monoclonal