Table 1.
Gamma Knife (GK) Studies and Patient Characteristics
| First Author, Year | N | Median SRS Dose (Gy); Range (Isodose) | Age Mean/Median; Range (yr) | Prior Therapy | NF2 | Median Tumor Volume; Range (cm3) | Mean f/u; Range (mo) | Median f/u; Range (mo) | Tumor Control at f/u | CN V Deficit | CN VII Deficit | Serviceable Hearing | Tinnitus | Post-SRS Hydrocephalus | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pre- SRS | Post- SRS | Pre- SRS | Post- SRS | Pre- SRS | Post- SRS | Pre-SRS | Post- SRS | |||||||||||
| Nagano, 2010a | 87 | 12;10.5-13 (52.2%) | 58.6/59; 29-80 | 27/87 (31.0%) | N/A | 1.9; 0.1-13.2 | 90; 60-133.2 | 85.2; 60-133.2 | 78/87 (89.7%) | 17/87 (19.5%) | 10/87 (11.5%) | N/A | 14/87 (16.1%) | N/A | N/A | N/A | N/A | N/A |
| Nakaya, 2010b | 202 | 13 (50%) | 61;18-95 | 0/202(0%) | 0/202(0%) | 3.9; 0.76-38.6 | 65; 12-179 | 196/202 (97%) | N/A | N/A | N/A | 7/200(3.5%) | 12/202(5.9%) | 9/186(4.8%) | N/A | N/A | N/A | |
| Wackym, 2010a | 59 | 12.84;11.7-14(50.6%) | N/A | 7/59(11.9%) | 0/59(0%) | N/A | 63.76; 9-109 | 65.5; 9-109 | N/A | 9/59 (15.3%) | 8/59 (13.6%) | 6/59 (10.2%) | 5/59(8.5%) | 38/59(64.4%) | N/A | 29/59(49.2%) | 26/59 (44.1%) | N/A |
| Sun, 2012b | 190 | 13;6-14.4 (45%) | 50.6;10-77 | 56/190 (29.5%) | 0/190(0%) | 3.6; 0.3-27.3 | 109;8-195 | 170/190 (89.5%) | 10/190 (5.3%) | 2/190 (1.1%) | 53/190 (27.9%) | 68/190 (35.8%) | 22/190(11.6%) | 18/190(9.5%) | 124/190 (65.3%) | 69/190 (36.3%) | 6/190 (3.2%) | |
| Yomo, 2012b | 154 | 12.1;9-14 (51.1%) | 54.1;24-76 | 0/154(0%) | 0/154(0%) | 0.73; 0.03-5.37 | 60;6-132 | 142/154 (92.2%) | N/A | 2/154 (1.3%) | N/A | 1/154 (0.65%) | 105/154 (68.2%) | 64/154 (41.6%) | N/A | N/A | N/A | |
| Carlson, 2013b | 44 | 12;12-13 (N/A) | 56.9/58; 36-72 | 0/44(0%) | 0/44(0%) | 0.715; 0.153-12 | 99.6; 60-168 | 111.6; 60-168 | N/A | N/A | N/A | N/A | N/A | 44/44(100%) | 8/44(18.2%) | N/A | N/A | N/A |
| Hasegawa, 2013b | 427 | 12.8;10-18 (50%) | 55; 7-86 | 93/427 (21.8%) | 13/427(3%) | 2.8; 0.07-36.7 | 150; N/A | 396/427 (92.7%) | N/A | N/A | 20/347 (5.8%) | 5/430(1.2%) | 117/117(100%) | 56/117(47.9%) | N/A | N/A | 25/427 (5.9%) | |
| Kim, 2013b | 58 | 12.2;11.5-13 (50.7%) | 49.6;21-69 | 0/58(0%) | 0/58(0%) | 0.34; 0.03-1 | 61.5; 36-141 | 51/58 (87.9%) | N/A | N/A | N/A | N/A | 60/60(100%) | 34/60(56.7%) | 32/60(53.3%) | N/A | N/A | |
| Massager, 2013b | 139 | 12;12-14 (N/A) | N/A | N/A | N/A | 1.1; 0.01-8.3 | 78;60-138 | 126/139 (90.6%) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | |
| Mindermann, 2013b | 235 | 12.9(N/A) | 57.3 | 20/235 (8.51%) | 0/235(0%) | 1.85 | 62.4; N/A | 214/235 (91.1%) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | |
| Anderson, 2014b | 48 | 12.5;9.7-16 (N/A) | N/A | 11/48 (22.9%) | 1/48(2.1%) | 0.66 | 83.6; N/A | 47/48 (97.0%) | 18/48 (37.5%) | 18/48 (37.5%) | 13/48 (27.1%) | 10/48 (20.8%) | 12/12(100%) | 7/12(58.3%) | 18/48 (37.5%) | 14/48 (29.2%) | ||
| Bir, 2014b | 82 | 12;12-13 (50%) | 62;14-89 | 20/82(24%) | N/A | 3.24; 0.24-16 | 60;6-144 | 74/82 (90.2%) | 0/82(0%) | 3/82(3.7%) | 16/82 (19.5%) | 5/82(6.1%) | N/A | N/A | 12/82(14.6%) | 9/82 (11.0%) | 1/82(1.2%) | |
| Boari, 2014b | 379 | 13;11-15 (50%) | 59/61; 23-85 | 0/379(0%) | 0/379(0%) | 1.2; 0.013-14.3 | 75.7/69.5; 36-157 | 368/379 (97.1%) | 37/379 (9.8%) | 24/379 (6.3%) | 29/379 (7.7%) | 11/379(2.9%) | 187/379 (49.3%) | 47/96(49%) | 150/379 (39.6%) | 142/379 (37.5%) | 20/379 (5.3%) | |
| Wangerid, 2014b | 128 | 12.3 (mean); 11-16(50-60%) | 64;23-89 | 0/128(0%) | 0/128(0%) | 1.65 (mean); 0.1-8.4 | 96;11-165 | 113/123 (91.9%) | N/A | 3/128 (2.3%) | 1/128 (0.78%) | 4/128 (3.13%) | N/A | N/A | 52/128 (40.6%) | N/A | 4/123 (3.3%) | |
| Akpinar, 2016b | 88 | 12.5;11.5-13 (N/A) | 47;20-71 | 0/88(0%) | 0/88(0%) | 0.72; 0.11-12.8 | 75;12-169 | 82/88 (93%) | 3/88(3.4%) | N/A | 3/88(3.4%) | 3/88(3.4%) | 88/88(100%) | 67/88(76.1%) | 56/88(63.6%) | N/A | N/A | |
| Klijn, 2016b | 420 | 11.1;8.8-13 (62%) | 57.6;15-86 | 0/420(0%) | 0/420(0%) | 1.4; 0.01-17.7 | 61.2; 2.4-144 | 375/420 (89.3%) | 65/420 (15.5%) | 13/420 (3.1%) | N/A | N/A | 71/71(100%) | 43/71(60.6%) | N/A | N/A | 5/420 (1.2%) | |
| Mousavi, 2016b | 166 | 12.5; 12-13 (N/A) | 49;20-71 | 0/166(0%) | 0/166(0%) | 0.8; 0.1-12.8 | 65;12-183 | 153/166 (92.2%) | 0/166(0%) | 0/166(0%) | 1/166 (0.60%) | 1/166 (0.60%) | 166/166(100%) | 112/166 (67.5%) | 89/166 (53.6%) | N/A | 0/166(0%) | |
| Watanabe, 2016b | 180 | 14.8; 13-18 (60%) | 56;11-80 | 56/183 (30.6%) | 10/183 (5.5%) | 2; 0.05-26.2 | 114; IQR 73-144 | 158/180 (87.8%) | 6/183 (3.3%) | 6/183 (3.3%) | N/A | N/A | 74/183(40.4%) | 23/66(34.8%) | N/A | N/A | 11/183 (6.0%) | |
| Lin, 2017b | 100 | 12;12-13(50%) | 50.1 (mean) | 0/100(0%) | N/A | Divided into size clusters | 78;36-120 | 85/100 (85.0%) | N/A | N/A | 7/100(7%) | N/A | 100/100(100%) | 61/100(61%) | 70/100 (70.0%) | N/A | N/A | |
| Pan, 2017b | 93 | 12(50%) | 58; 57.7-15.1 | 0/93(0%) | 0/93(0%) | 3.14(mean) | 76.3 | N/A | 9/93(9.7%) | N/A | 5/93(5.4%) | 4/93(4.3%) | 64/64(100%) | 12/64(18.8%) | 46/93(49.5%) | 36/93 (38.7%) | 1/93(1.1%) | |
| Tveiten, 2017b | 247 | 12 Gy(50%) | 58.2 | 0/247(0%) | 0/247(0%) | Divided into size clusters | 92.4 | N/A | N/A | N/A | 4/247 (1.6%) | 9/247(3.6%) | N/A | N/A | N/A | N/A | N/A | |
| Wu, 2017b | 187 | 12;11-13 (N/A) | 52.2; 20.4-82.3 | 0/187(0%) | 0/187(0%) | 2; 0.1-16.2 | 60.8; 24-128.9 | 170/187 (90.9%) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | |
| Hasegawa, 2018b | 92 | 12;10.4-16.8 (50%) | 54;17-77 | 1/92(1%) | 0/92(0%) | 1.5;0.1-14.5 | 106; 36-262 | 90/92 (97.8%) | 4/92(4.3%) | 1/92(1.1%) | 1/92(1.1%) | 0/92(0%) | 92/92(100%) | 49/92(53.3%) | N/A | N/A | N/A | |
| Milner, 2018b | 45 | 12-13(50%) | 55.8;34-75 | 0/45(0%) | 0/45(0%) | 1.75;0.012-9.504 | 69.6; 19-209 | N/A | N/A | N/A | N/A | N/A | 27/45(60%) | 4/43(9.3%) | N/A | N/A | N/A | |
| Johnson, 2019b | 871 | 13;8-25 (N/A) | 57;19-95 | 0/871(0%) | 0/871(0%) | 0.9;0.02-36 | 62.4; 12-300 | 844/871 (96.9%) | N/A | N/A | N/A | N/A | 326/326(100%) | 196/326 (60.1%) | 536/871 (61.5%) | 510/817 (62.4%) | N/A | |
| Johnson, 2019 b | 307 | 12.5;12-15 (N/A) | 52;20-85 | 0/307(0%) | 0/307(0%) | 0.7;0.02-16.7 | 91.2; 12-276 | 291/307 (94.8%) | N/A | 18/307 (5.9%) | N/A | 0/307(0%) | 307/307(100%) | 186/307 (60.6%) | N/A | N/A | 1/307 (0.33%) | |
| Langenhuizen, 2019b | 311 | 11.9;9.5-13.6(55%) | 59;24-85 | 0/311(0%) | 0/311(0%) | 1.16;0.06-12.18 | 60;19-159 | 276/311 (88.7%) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | |
| Tucker, 2019b | 52 | 12.5;12-16 (50%) | 59.8/63.7; 19.4-84.2 | 6/52(11.5%) | 0/52(0%) | 2.41;0.09-12.8 | 69;12-192 | 51/52 (98.1%) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 1/52(1.9%) | |
| Shinya, 2019b | 397 | 13(N/A) | 56 | 88/397 (22%) | 0/397(0%) | 2 | 103 | 373/397 (94.0%) | N/A | 12/422 (2.8%) | N/A | N/A | 181/422 (42.9%) | 91/422 (21.6%) | N/A | N/A | 15/397 (3.8%) | |
Abbreviations: CN, cranial nerve; f/u, follow-up; GK, gamma knife; IQR, interquartile range; N/A indicates not reported, excluded from analysis, or unable to determine; NF2, neurofibromatosis type 2; SRS, stereotactic radiosurgery.
aProspective study.
bRetrospective study.
A total of 29 studies investigating the long-term outcomes of GK SRS were included. GK SRS was most commonly delivered as a single fraction with a median of 11-13 Gy at the 57% isodose line. Relevant patient characteristics (age, prior therapy, NF2, tumor volume) and treatment outcomes (tumor control, CN impairment, hearing preservation, tinnitus, hydrocephalus) are summarized.