GK/FSR statistics - Acouistic Neuroma Patient Archive

Gamma Knife, LINAC, and Proton Beam:
comparison of recent radiosurgery outcomes

Additional useful information in the Acoustic Neuroma Patient Archive:

Outcome Measure	Pittsburgh GK	Virginia GK	Jefferson Univ GK	Jefferson Univ FSR	Johns Hopkins FSR	Stanford FSR	Staten Island Univ. Hosp. FSR	Loma Linda Proton
Tumor Growth Control Rate	97.1 +/- 1.9%	94%	98%	97- 100%	100%	97%	99%	100%
New-onset of transient or permanent facial weakness	1.1 +/- 0.8%¹	2.2% trans / 0-1.3% perm	2%	7%	0%	3%	0-1%	0%
New-onset of transient or permanent facial numbness	2.6 +/- 1.2%	4% trans / 1.6% perm	2%	2%	0%	16%	0-1%	0%
Hearing-level preservation	71+/-4.7%	58%			73%	77%	69-94
Preservation of useful hearing²	73.5+/-5.9%		33% (4 of 12)	81% (17 of 21)				31% (4 of 13)
Improved or resolved tinnitus		11% (3 of 26)
Treatment Details	Pittsburgh GK	Virginia GK	Jefferson Univ GK	Jefferson Univ FSR	Johns Hopkins FSR	Stanford FSR	Staten Island Univ. Hosp. FSR	Loma Linda Proton
Number of patients included			69	65	125			30
Period of follow-up (years)	2-7	1-10	2.3	2.2	1-5.7	0.5-4	3.5 yrs	2.8
Tumor size (cm): mean diameter / range	1.72 / 0.6-4	1.74 / 0.3-3.2	1.77	1.74	1.2 - 9.3cc³	2.0 / 0.7-4.2	2.6 cm	2.0 cm
Tumor dosage (Gy): mean / range	26 / 22-36	34.3 / 17-53	?	50 Gy in 35 fractions	25-30 in 5 or 10 fractions	21 Gy in 3 fractions	20 Gy in 4 or 5 fractions	54 Gy in 30 fractions
Dosage to tumor margin (Gy): mean / range	13 / 11-18	13.2	12 Gy

Facial weakness did not develop in any patient who received a marginal dose of less than 15 Gy (163 patients).

Useful hearing in the affected ear means "testable speech discrimination", defined as Gardner-Robertson grades 1 and 2, PTA (pure tone average) at 0-50dB and SDS (speech discrimination score) at 50-100%; hearing levels below that are not considered useful, and were not reported.

The tumor was measured by volume (cc's) rather than size (cm's).

Sources:

For Pittsburgh, 190 cases, 1992-97:
Flickinger et al,
"Results of acoustic neuroma radiosurgery: an analysis of 5 years experience using current methods,"
Journal of Neurosurgery, vol 94 (Jan 2001).

For Virginia, 200 cases, 1989-99:
D.Prasad, L.Steiner & M.Steiner,
"Gamma Surgery for Vestibular Schwannoma,"
Journal of Neurosurgery, vol 92 (May 2000).

For Johns Hopkins, 249 cases, 1995-2001:
Jeffery A. Williams,
"Fractionated Stereotactic Radiotherapy (FSR) for Acoustic Neuromas"
Congress of Neurological Surgeons Annual Meeting, San Diego (Oct. 2001).
http://www.med.jhu.edu/radiosurgery/publish/acoustic/abstracts/abstract1.html

For Stanford, 33 cases, n.d:
J.C.Poen et al,
"Fractionated Stereotactic Radiosurgery and Preservation of Hearing in Patients with Vestibular Schwannoma: A Preliminary Report,"
Journal of Neurosurgery, vol 45 (December 1999).

For Jefferson University Hospital:
David W.Andrews et al,
"Stereotactic Radiosurgery and Fractionated Stereotactic Radiotherapy for the Treatment of Acoustic Schwannomas: Comparative Obsertations of 125 Patients Treated at One Institution,"
Int J. Radiation Oncology Biol Phys, vol 50 (2001).

For SIUH:
communicated by e-mail, see AN News from 1/01

For Loma Linda:
D.A.Bush et al,
"Fractionated Proton Beam Radiotherapy for Acoustic Neuroma,"
Journal of Neurosurgery, Vol 50 (2002).

Last Edited: Saturday, February 14, 2004

Gamma Knife, LINAC, and Proton Beam: comparison of recent radiosurgery outcomes

Gamma Knife, LINAC, and Proton Beam:
comparison of recent radiosurgery outcomes