Table 4 Literature review of aggressive meningiomas treated by gamma knife

Ojemann et al., 2000 [20]

3

19 (31)

Mean 16

18

5 year 26%

5 year 40%

PFS and OS: age (p < 0.003), tumor volume (p < 0.05)

Stafford et al., 2001 [21]

2

13

Median 16

36

5 year 68%

5 year 76%*

3

9

5 year 0%

5 year 0%*

Harris et al., 2003 [22]

2

18

Mean 14.9

29.4

5 year 83%

5 and 10 year 59%

PFS: early SRS (p < 0.001), small tumor volume (p < 0.001)

3

12

Mean 15.7

31.4

5 year 72%

5 year 59% 10 year 0%

OS: younger age (p = 0.03)

Huffmann et al., 2005 [23]

2

15 (21)

18

6 months 93%

100% at median follow up of 35 months

Kondziolka et al., 2008 [24]

2

54

50% at median of 2 years

3

29

17% at median of 15 months

Attia et al., 2012 [25]

2

24

Median 14

18

1 year 75%

2 year 40%

1 year 92%

PFS: dose > 14 Gy (p = 0.01)

2 year 51%

5 year 25%

2 year 67%

5 year 44%

5 year 52%

Mori et al., 2013 [26]

2

19 (22)

Mean 16.5

20.15

1 year 74%,

3

4

2 year 54%,

3 year 34%

Tamura et al., 2013 [27]

2

9

Mean 18.8

37

Stabilization of tumor growth: small lesion volume (p = 0.02), marginal dose (p = 0.04), max dose (p = 0.02)

3

7

Current series

2

31

Median 18

24

1 year 95.7% 3 year 70.1%

1 year 92.4% 3 year 83.4%

Recurrence: WHO grade 2 histology (p = 0.0134)

3

4

1 and 3 year 0%

1 and 3 year 33.3%

OS: WHO grade 2 histology (p = 0.0386), treated tumor volume (p = 0.0095)