Delayed microsurgery for vestibular schwannoma after gamma knife radiosurgery.
Stereotactic radiosurgery for vestibular schwannomas (VSs) has become popular during the last decade with promising clinical results after long-term follow-up. However, on rare occasions, some cases have needed traditional microsurgery to remove the tumor several months or years after radiosurgery. We present a retrospective analysis of data acquired during a 16-year period in delayed microsurgery of seven patients with VSs who underwent gamma knife surgery (GKS). A total of 444 with VS underwent GKS between March 1993 and December 2008, and 7 (1.57%) underwent delayed microsurgery at a median of 26 months (range from 3 months to 6 years) after GKS. The mean size of the tumor during GKS was 10.4 ml (range 2.3-23.5 ml). These seven patients were younger, and female predominant. The indications of microsurgery included adverse radiation effect with peri-focal edema, tumor enlargement, and cyst enlargement. Although the perifocal edema could lead to more difficulty in surgery than in typically performed operations for schwannoma, subtotal resection was achieved in all patients. There was no surgery-related morbidity or mortality. The histology showed benign tumor in five patients, malignant peripheral nerve sheath tumor in one, and necrotic tissue in one. The need of microsurgery for further treatment of VS after radiosurgery is rare, but can be a challenge to neurosurgeons in terms of surgical indication, timing, and techniques. The authors concluded the incidence of delayed microsurgery was 1.57% in a series of 444 patients over a 16-year period. We concluded some experience from operative indications, timing, approach, and outcome.
Lee
Cheng-Chia
CC
Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, 17F, No. 201, Shih-Pai Road, Sec. 2, Peitou, Taipei, 11217, Taiwan, ROC. yfnaughty@gmail.com
Yen
Yu-Shu
YS
Pan
David Hung-Chi
DH
Chung
Wen-Yuh
WY
Wu
Hsin-Mei
HM
Guo
Wan-Yuo
WY
Chen
Ming-Te
MT
Liu
Kang-Du
KD
Shih
Yang-Hsin
YH
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D019394:Ki-67 Antigen / Q000378:metabolism; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology* / Q000601:surgery*; D016634:Radiosurgery / Q000009:adverse effects*; D012189:Retrospective Studies; D009418:S100 Proteins / Q000378:metabolism; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
D019394:Ki-67 Antigen; D009418:S100 Proteins
J Neurosurg. 2005 Jan;102 Suppl:87-96
15662787
J Laryngol Otol. 1994 May;108(5):375-9
8035113
J Neurosurg. 1998 Dec;89(6):949-55
9833821
J Neurosurg. 2001 Sep;95(3):518-21
11565878
J Neurosurg. 1992 May;76(5):874-7
1564550
Acta Neurochir (Wien). 2002 Jul;144(7):671-6; discussion 676-7
12181700
J Neurosurg. 2001 Jan;94(1):7-13
11147901
J Laryngol Otol. 2000 Dec;114(12):935-9
11177361
Acta Otolaryngol Suppl. 2000;543:11-3
10908962
J Neurosurg. 2006 Oct;105(4):576-80
17044561
J Korean Med Sci. 2001 Dec;16(6):817-21
11748371
Clin Neurosurg. 1993;40:498-535
8111998
J Neurosurg. 1990 Dec;73(6):946-50
2230979
Lancet. 2002 Jul 27;360(9329):309-10
12147377
J Neurosurg. 1991 Mar;74(3):422-5
1993907
Acta Neuropathol. 1987;74(1):92-6
3499046
Acta Neurochir (Wien). 2007 Mar;149(3):313-6; discussion 316-7
17273886
J Neurosurg. 2000 May;92(5):745-59
10794287
Cancer. 2005 Aug 1;104(3):580-90
15952200
N Engl J Med. 1998 Nov 12;339(20):1426-33
9811917
Neurosurgery. 1997 Mar;40(3):469-81; discussion 481-2
9055285
Am J Surg Pathol. 2009 Mar;33(3):325-38
19065105
Acta Neurochir (Wien). 1996;138(6):695-9
8836284
J Clin Pathol. 2004 Jan;57(1):109-10
14693854
J Neurol Neurosurg Psychiatry. 2003 Jul;74(7):908-12
12810777
Arch Pathol Lab Med. 1983 Jun;107(6):293-7
6687792
Am J Otol. 1995 May;16(3):315-9; discussion 319-21
8588625
J Neurosurg. 1998 Oct;89(4):653-8
9761063
Stereotact Funct Neurosurg. 1996;66 Suppl 1:103-11
9032850
Neurosurgery. 2008 May;62(5):E1164-5; discussion E1165
18580785