Articles
262
www.thelancet.com/oncologyVol 10 March 2009
of brainstem ischaemia on postoperative T2-weighted
MRI, required tracheostomy, and had postoperative
hypertension needing medication. Two of the three also
had a history of a postoperative seizures. There were no
other cases of necrosis and no other patients had a
similar constellation of clinical signs and symptoms
before or during radiotherapy. Including all three cases
of necrosis, the cumulative incidence of brainstem
necrosis at 7 years was 2·5% (95% CI 0·0–5·2);
excluding the patient who died after a seizure, it was
1·6% (0·0–4·0).
Seizure disorders required chronic medication in five
patients with supratentorial tumour location. Two needed
surgery for epilepsy and were able to reduce or stop
medication. There was one case of radiation-related
cerebral vasculopathy in a patient with infratentorial
tumour location that required revascularisation surgery.
The patient was aged 12 months at the time of irradiation
and the high-dose volume encompassed the Circle of
Willis.
7-year estimates of local control, EFS, and overall survival
were 87·3% (95% CI 77·5–97·1), 69·1% (56·9–81·3), and
81·0% (71·0–91·0), respectively (figure 2). Median time to
progression was 22·5 months (range 5·0–90·9) from
diagnosis and 20·3 months (3·1–75·4) from the start of
conformal radiotherapy.
Univariate analyses of overall survival by various clinical
variables are presented in table 2. Multiple regression
analysis showed overall survival was affected by tumour
grade, extent of resection, and ethnic origin: gross-total
resection was associated with a lower risk of death from
any cause than was near-total or subtotal resection
(HR 0·16 [95% CI 0·07–0·37]; p<0·0001), while the risk of
death was greater in patients with anaplastic tumours
than in those with differentiated tumours (HR 3·98
[1·51–10·48]; p=0·0052) and in non-white patients versus
white patients (HR 3·0 [1·21–7·44]; p=0·018). However,
death from necrosis accounted for the lower overall
survival in non-white patients, compared with white
patients: when we excluded the two patients who died of
necrosis, the comparison of ethnic origin was not
significant for overall survival (HR 2·1 [0·8–5·7]; p=0·16
by univariate analysis). The use of chemotherapy before
conformal radiotherapy was associated with a lower overall
N Event-free survival (%)
Overall survival (%)
5 years (95% CI)
7 years (95% CI)
HR (95% CI)
p
5 years (95% CI)
7 years (95% CI)
HR (95% CI)
p
Tumour grade
Differentiated
68 86·4 (76·8–96·0)
79·2 (66·1–92·3)
1·0
0·005 91·9 (84·3–99·5)
89·4 (79·6–99·2)
1·0
0·006
Anaplastic
85
61·3 (46·4–76·2)
61·3 (38·8–83·8)
2·58 (1·30–5·12)
··
78·3 (66·3–90·3)
71·8 (52·6–91·0)
3·56 (1·37–9·22)
··
Tumour location
Infratentorial
122
71·1 (60·5–81·7)
65·8 (52·7–78·9)
1·0
0·16 84·0 (75·6–92·4)
80·5 (69·5–91·5)
1·0
0·6
Supratentorial
31
82·9 (66·6–99·2)
82·9 (57·6–100·0)
0·52 (0·20–1·32)
··
89·5 (76·8–100·0)
83·1 (59·4–100·0) 0·75 (0·25–2·22)
··
Ethnic origin
White
126 75·5 (66·3–84·7)
70·4 (57·7–83·1)
1·0
0·26 87·7 (80·6–94·8)
84·5 (74·7–94·3)
1·0
0·017
Other
27
64·5 (30·8–98·2)
64·5 (30·8–98·2)
1·55 (0·71–3·38)
··
72·9 (44·9–100·0)
60·7 (27·4–94·0)
2·84 (1·16–6·92)
··
Sex
Female
58 84·7 (73·9–95·5)
81·0 (66·3–95·7)
1·0
0·018 91·8 (83·8–99·8)
88·6 (76·8–100·0) 1·0
0·091
Male
95
66·7 (53·4–80·0)
61·0 (43·4–78·6)
2·40 (1·13–5·06)
··
81·1 (70·1–92·1)
76·0 (61·1–90·9)
2·20 (0·86–5·61)
··
Age at CRT (years)
≥3
75
79·0 (66·8–91·2)
69·4 (52·2–86·6)
1·0
0·37
90·1 (81·1–99·1)
81·7 (68·0–95·4)
1·0
0·46
<3
78 68·6 (55·7–81·5)
68·6 (52·1–85·1)
1·34 (0·71–2·52)
··
80·4 (69·8–91·0)
80·4 (66·1–94·7)
1·37 (0·60–3·12)
··
Total dose (Gy)
54
22
80·7 (61·5–99·9)
70·6 (44·1–97·1)
1·0
0·67
85·4 (68·9–100·0)
77·7 (53·8–100·0) 1·0
0·82
59·4
131
72·4 (62·4–82·4)
68·8 (55·5–82·1)
1·04 (0·87–1·24)
··
85·0 (77·0–93·0)
81·6 (70·8–92·4)
0·98 (0·80–1·19)
··
Number of surgical procedures
1
87
79·7 (69·3–90·1)
74·4 (60·3–88·5)
0·55 (0·29–1·02)
0·056 90·1 (82·7–97·5)
83·9 (72·3–95·5)
0·56 (0·24–1·26)
0·15
2–4
66 65·6 (49·5–81·7)
62·0 (41·2–82·8)
1·0
··
78·4 (64·5–92·3)
78·4 (60·6–96·2)
1·0
··
Surgical extent
GTR
125
81·5 (72·7–90·3)
77·3 (65·0–89·6)
0·21 (0·11–0·40)
<0·
0001 93·0 (87·3–98·7)
88·0 (78·8–97·2)
0·16 (0·07–0·36)
<0·0001
NTR or STR
28 41·0 (17·7–64·3)
34·2 (12·1–56·3)
1·0
··
52·4 (25·5–79·3)
52·4 (25·5–79·3)
1·0
··
Pre-CRT chemotherapy
Yes
35
59·4 (39·6–79·2)
48·7 (26·0–71·4)
1·0
0·008 73·6 (55·6–91·6)
66·9 (43·0–90·8)
1·0
0·038
No
118 78·1 (68·3–87·9)
75·9 (62·8–89·0)
0·43 (0·22–0·81)
··
88·6 (81·3–95·9)
85·3 (75·1–95·5)
0·42 (0·18–0·98)
··
HR=hazard ratio. CRT=conformal radiotherapy. GTR=gross-total resection. NTR=near-total resection. STR=subtotal resection.
Table 2:
Univariate analysis of event-free survival and overall survival according to different variables