paediatrics Brussels 17

Ramaswamy et al

Patients With GTR EPN_PFB Have an Excellent Prognosis As a result of limited patient numbers, we combined patients with EPN_PFB from the GENE, St Jude RT1, and CERN cohorts and demonstrated that STR results in a high risk of relapse (10-year PFS for GTR, 0.740; 95% CI, 0.550 to 0.859; 10-year PFS for STR, 0.50; 95% CI, 0.271 to 0.692). These fi ndings were con fi rmed in a cohort of patients with EPN_PFB treated at the Burdenko In- stitute ( Fig 3 ). As a result of the similar behavior of the two cohorts and the relatively small number of patients with EPN_PFB in each cohort, we combined all patients in our subsequent multivariable analysis. In a multivariable analysis restricted to EPN_PFB, a similar

St Jude RT1 cohort received adjuvant postoperative radiation. Strikingly, survival for STR EPN_PFA was not different between those who received fi rst-line external-beam radiation and those who did not in the CERN and Burdenko cohorts (Appendix Fig A6 , online only). In the GENE cohort, there was a statistically sig- ni fi cant difference by a univariable analysis in patients who did not receive radiation; however, survival remains poor even in patients with subtotal resections who received external-beam irradiation. These data suggest that the bene fi t of post-surgical fi rst-line adjuvant external-beam irradiation for patients with EPN_PFA is limited in the face of a subtotal resection and that these patients should be prioritized for clinical trials of novel therapy.

A

B

1.00

1.00

0.75

0.75

0.50

0.50

0.25 OS (probability)

0.25

PFS (probability)

No first-line XRT First-line XRT

No first-line XRT First-line XRT

P = .1

P = .4

0 1 2 3 4 5 6 7 8 9 10 Time Since Diagnosis (years)

0 1 2 3 4 5 6 7 8 9 10 Time Since Diagnosis (years)

No first-line XRT First-line XRT No. at risk

First-line XRT No. at risk

29 27 26 25 21 19 18 14 11 8 5 61 56 52 46 38 36 30 25 21 16 14

29 26 25 24 20 18 17 14 11 8 5 61 55 49 44 36 35 29 24 20 14 13

No first-line XRT

C

D

1.00

1.00

0.75

0.75

0.50

0.50

0.25 OS (probability)

0.25

PFS (probability)

No first-line XRT First-line XRT

No first-line XRT First-line XRT

P = .6

P = .3

0

1 2 3 4 5 6 7 8 9 10 Time Since Diagnosis (years)

0 1 2 3 4 5 6 7 8 9 10 Time Since Diagnosis (years)

No. at risk

First-line XRT No. at risk

7 7 6 6 5 4 4 4 2 1 1 39 37 34 27 23 18 13 9 8 5 2

7 6 6 6 5 4 4 3 2 1 1 40 36 29 21 17 13 9 6 5 4 2

No first-line XRT First-line XRT

No first-line XRT

Fig 3. Value of adjuvant post-operative fi rst-line external-beam irradiation (XRT) in EPN_PFB. (A) Progression-free survival (PFS) and (B) overall survival (OS) of EPN_PFB across the Global Ependymoma Network of Excellence, St Jude ’ s, and Collaborative Ependymoma Research Network cohorts. (C) PFS and (D) OS of EPN_PFB across the Burdenko cohort. P values determined using log-rank test.

6 © 2016 by American Society of Clinical Oncology

J OURNAL OF C LINICAL O NCOLOGY

from 139.18.224.1 Information downloaded from jco.ascopubs.org and provided by at UNIVERSITAETSKLINIKUM LEIPZIG on June 20, 2016 Copyright © 2016 American S ciety of Clinical Oncology. All rights reserved.