Gamma Knife radiosurgery for neurofibromatosis type 2-associated meningiomas: a 22-year patient series.
Neurofibromatosis type 2 (NF2) is a debilitating genetic condition with potential development of multiple meningiomas. We report our experience treating a series of NF2-associated intracranial meningiomas with Gamma Knife radiosurgery (GKRS). Between 1992 and 2013, 15 consecutive patients (age 20-54 years) with 62 intracranial meningiomas were treated with single-fraction GKRS. Fifty-five percent of tumors involved the convexity or parasagittal/falx. The median prescription dose was 16 Gy (range 13-20 Gy). The median tumor diameter was 2.1 cm (range 0.7-4.5 cm). The median radiographic and clinical follow-up periods were 103 and 111 months, respectively. The 5-year and 10-year local controls were both 96 %. The disease specific survival was 93 % at 5 years and 68 % at 10 years. Fifty-three percent of patients had multiple meningiomas and received multiple GKRS treatments (range 1-7) for new or enlarging intracranial meningiomas. 11 (73 %) patients were alive at last follow-up, with 60 (97 %) tumors controlled (smaller or unchanged in size). There were 2 in-field failures, one at 1 year and the other at 3.5 years. There were no marginal failures. Major Complications after GKRS included: 1 case of radiation necrosis, 1 case of post treatment edema, and 1 case of a presumed radiation induced cavernous malformation 5 years after GKRS. GK is an effective treatment for enlarging NF2-associated meningiomas. No cases of malignant transformation or secondary malignancies were seen during the follow-up period.
Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, USA.
Brandon
B
Birckhead
Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, USA.
Terence T
TT
Sio
Department of Neurosurgery, Mayo Clinic, Rochester, MN, USA.
Bruce E
BE
Pollock
Department of Neurosurgery, Mayo Clinic, Rochester, MN, USA.
Michael J
MJ
Link
Department of Radiation Oncology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. laack.nadia@mayo.edu.
Nadia N
NN
Laack
D000293:Adolescent; D000328:Adult; D002648:Child; D015331:Cohort Studies; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000378:metabolism / Q000401:mortality / Q000532:radiotherapy*; D008579:Meningioma / Q000378:metabolism / Q000401:mortality / Q000532:radiotherapy*; D008875:Middle Aged; D025581:Neurofibromin 2 / Q000378:metabolism*; D016634:Radiosurgery / Q000379:methods*; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
D025581:Neurofibromin 2
Gamma Knife; Meningioma; Neurofibromatosis; Radiotherapy; Stereotactic radiosurgery