paediatrics Brussels 17

I. J. Radiation Oncology d Biology d Physics

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Volume 74, Number 5, 2009

complete. Another patient considered to have undergone par- tial resection underwent placement of a ventriculoperitoneal shunt. Severe acute complications developed in 6 patients consisting of cranial nerve paralysis with swallowing diffi- culties in 3, akinetic mutism in 1, both disturbances in 1, and hemiplegia in association with an intracranial postopera- tive hematoma in 1. Central radiologic review Both postoperative CT and MRI were performed in 11 cases, MRI only in 11 cases, and CT only in 2. At the central radiologic review, the resection was considered complete in 16 of the 24 patients and doubtful or partial in 4 each. Of the 20 patients with infratentorial EP and the 4 patients with supratentorial EP, 14 and 2, respectively, underwent CR. In 6 children with infratentorial tumors, a discrepancy was found between the operative report and the early postop- erative imaging results. The central radiologic review showed radiologic residual disease in 1 case that had been considered a CR by the surgeon. In contrast, no residual mass was found in 5 patients for whom the neurosurgeon had reported subtotal surgery. Only the extent of resection as defined by the panel of experts was considered for statistical analysis. Radiotherapy Radiotherapy was performed in all patients, a median of 31 days (range, 20–97) after surgery. In 5 cases, RT was started >40 days after surgery. In 1 case, the interval was as long as 97 days because of second-look surgery. That patient was considered to have undergone a CR before the initiation of RT. For all patients, the mean interval between RT sessions was $ 6 h. The energy was >8 MeV in 22 cases and equal to 6 MeV in 2. Of the 24 children, 18 received 60 Gy. Of these 18 patients, 14 had undergone a CR, 1 an incomplete, and 3 a doubtful resection, as determined after central review. Another 5 children received 66 Gy. Of these 5, 1 had under- gone a CR, 3 an incomplete, and 1 a doubtful resection. One patient with a CR received 54 Gy owing to a protocol

violation. HFRT was conformational in 20 patients. Of the 4 patients with measurable residual disease, 3 had an objec- tive response to HFRT. No severe acute complications of HFRT were reported. PFS and OS The median follow-up was 87.5 months (95% confidence interval, 66–90). Of the 24 patients, 8 died, all of neoplastic evolution. The estimated 3- and 5-year OS rate was 79.2% and 74.8%, respectively ( Fig. 1 ). The 3- and 5-year PFS rate was 62.5% and 54.2%, respectively. Prognostic factors analysis Tumor grade and extent of resection were selected to be tested as potential prognosis factors. The extent of resection was assessed by the central radiologic review committee. The two-tailed test failed to find any statistically significant differ- ence ( Table 1 ). Patterns of failure At the last follow-up visit, 12 patients were in their first complete remission, 2 were in their second or greater 3-year OS: 79.2 % , IC95 % [63.9; 95.4]; 3-year PFS: 62.5 % , IC95 % [43.1; 81.9] 5-year OS: 74.8 % , IC95 % [57.3; 92.3]; 5-year PFS: 54.2 % , IC95 % [34.2; 74.1] Fig. 1. Overall survival (OS) and progression-free survival (PFS) rates of 24 patients with intracranial ependymoma. 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 0 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 OS PFS Months

Table 1. Univariate analysis of correlation between selected parameters and estimated PFS and OS rates

n

p

p

Characteristic

5-y PFS (%)

5-y OS (%)

Grade

.849

.833

2 3

13 10

53.8 (24.8–76.0) 50.0 (18.3–75.3)

76.2 (42.7–91.7) 70.0 (25.3–82.7)

Location

.465

.854

Supratentorial Infratentorial

4

75.0 (12.8–96.1) 50.0 (27.1–69.2)

75.0 (12.8–96.1) 74.7 (49.3–86.6)

20

Extent of resection *

.842

.269

Complete

16

56.3 (29.5–76.2) 50.0 (15.3–77.5)

81.3 (52.4–93.5) 62.5 (29.9–86.0)

Partial or doubtful Radiation dose (Gy)

8

.561

.991

# 60

19

52.6 (28.7–71.9) 80.0 (20.3–96.9)

73.7 (47.9–88.1) 80.0 (20.3–96.9)

66

5

Abbreviations: PFS = progression-free survival; OS = overall survival. Data in parentheses are 95% confidence intervals. * As assessed by central radiologic review.