paediatrics Brussels 17

Ependymoma Survival: A SEER Study

67

Patients with ICD-0-3 histology codes 9391- 9494 n = 635

Primary tumor site ICD-0-2 site codes

Supratentorial 700, 702-714

Infratentorial 716-717

Spinal 701, 720-721

Undetermined 715,718-719, 728-729

Patients Included n = 354

Patients Excluded n = 281

Fig. 1.

Patient selection for primary tumor site analysis. n, number of children.

DISCUSSION

1.0

Supratentorial Infratentorial Spinal

Our study draws a large sample of 635 patients with ependymomas from a population-based cancer registry. Both age and location directly influence survival in children, consistent with prior research [1–3,8–10,12]. Although the current therapy for ependymomas in children often includes surgery followed by radiotherapy, variations in treatment plans using or not using radiotherapy have occurred because of concerns about neurotoxicity in young children [11]. Chemotherapy may be provided to delay the radiation therapy until older age, and sometimes children did not receive any irradiation for infratentorial ependymomas [14,15]. Specifically, Grundy et al. [16] found that among children less than 3 years without metastases from ependymoma, chemotherapy alone following maximal surgery provided an effective 42% 5-year cumulative incidence of freedom from radiotherapy. Duffner et al. [15], however, recorded excessive relapses in infants with an approach to defer radiotherapy by chemotherapy alone longer than 12 months. Furthermore, Merchant et al. reported that conformal irradiation in children achieves 74.7% progression free survival at 3 years from diagnosis. Among patients less than age 3 at time of irradiation, 3-year progression free survival was not significantly different at 69.5%with normal neurocognitive outcome scores [17]. In our study, radiotherapy was associated with improved outcomes, consistent with recent work by Shu et al. [8] that analyzed the treatment of 61 patients and found improved survival among children with higher radiation dose. However, following stratification, our study demonstrated a survival benefit of

0.8

0.6

0.4

0.2 Cumulative survival

0.0

0.00

100.00

200.00

300.00

400.00

Total survival time (months)

Fig. 2. Survival by primary tumor site. Total number of patients ¼ 354. Number of patients in each arm: supratentorial ¼ 106, infratentorial ¼ 193, spinal ¼ 55. Logrank Test, P ¼ 0.001.

both location ( P ¼ 0.020) and age ( P < 0.001) remained as significant predictors of survival among pediatric ependymomas, while radiotherapy did not retain significance. There was no interaction between age and location.

TABLE III. Five-Year Univariate Survival Estimates by Primary Tumor Site

Primary tumor site

n

5-year survival (%)

SE (%)

95% confidence interval

Supratentorial Infratentorial

106 193

57.8 54.4 86.6

5.5 4.2 5.2

(47.0, 68.6) (46.1, 62.6) (76.4, 96.8)

Spinal

55

n, number of children; SE, standard error.

Pediatr Blood Cancer DOI 10.1002/pbc