paediatrics Brussels 17

Radiotherapy Dose and Volume for Ependymoma

459

TABLE II. Pattern of Recurrence

Pattern of recurrence

Local þ Distant

Series

Number of patients

Local

Distant

Goldwein Vanuytsel

51 88 25 65 37 37 41 32 52 48

29 (56.9%) 45 (51.1%) 12 (48.0%) 20 (30.8%) 14 (37.8%) 17 (45.9%) 7 (17.1%) 20 (62.5%) 17 (32.7%) 20 (41.7%) (35%)

1 (2.0%) 2 (2.3%) 2 (8.0%)

5 (5.7%)

Chiu

Rousseau

10 (15.4%) 4 (10.8%) 2 (5.4%) 7 (17.1%)

3 (4.6%)

Carrie

Pollack Stuben Schild

45 (incl spine)

(13%)

McLaughlin

1 (3.1%) 4 (7.7%)

Paulino

Oya

6 (12.5%)

PTV and margins for CTV have generally varied from approximately 1 to 2 cm, and sometimes the whole post- erior fossa. In a report from St. Jude’s Children’s Hospital, 64 patients with EP have been included in a study of conformal RT using a margin of 1 cm for CTVaround the GTV [17]. With a follow-up of 17 months (range 3– 43 months) there have been six recurrences. Failure occurred within the CTV for five patients including three with concurrent leptomeningeal relapse. One patient developed metastatic disease with no evidence of local failure. In this series treatment of a CTV encompassing 1.0 cm of brain around the margin of resection and/or any residual tumour on MR scan appeared to be safe. Whether this guideline is suitable for determination of the CTV in a multi-institutional setting will be the subject of the planned COG study. MANAGEMENT OF ANAPLASTIC EPENDYMOMA The majority of series report a worse outcome for anaplastic (WHO grade III) compared with WHO grade II EP. The majority of these series are from single

EP it would be worthwhile to include duration of RT together with other RT parameters.

PATTERN OF RECURRENCE Table II summarises the pattern of recurrence from 11 series. The pattern of recurrence is predominantly local, with a low risk of leptomeningeal relapse. RT VOLUME In a literature review, there was no evidence to support the use of extended field or craniospinal RT [7]. Further series provide further confirmation of this view (Table III). In one series, for eight patients presenting with leptome- ningeal metastases a 5-year PFS of 37% was reported [5] and in another series three of six [14] have remained disease free after CSRT. The role of CSRT for patients presenting with leptomeningeal relapse needs further evaluation. For patients treated by local RT there has been no consistent recommendation for extent of CTV around the

TABLE III. Influence of Extent of RT Volume on Outcome

Outcome

Author [reference]

Local RT

Craniospinal RT

Goldwein et al., 1990 [6] Vanuytsel et al., 1992 [7]

31% 5-Year PFS 38% 5-Year PFS

27% 5-Year PFS 46% 5-Year PFS

Chiu et al., 1992 [8]

1/12 Leptomeningeal relapses

0/7 Leptomeningeal relapses

Rousseau et al., 1994 [4] Carrie et al., 1995 [9] Pollack et al., 1995 [5] Stuben et al., 1997 [10] Schild et al., 1998 [11] McLaughlin et al., 1998 [12] Paulino et al., 2002 [13]

40% 5-Year EFS

49% 5-Year EFS

0/5 Relapses

7/11 Relapses

70% 5-Year PFS 58% 5-Year PFS

51% 5-Year PFS 45% 5-Year PFS

9% Leptomeningeal relapses 1/17 Leptomeningeal relapses

24% Leptomeningeal relapses 0/15 Leptomeningeal relapses

80.8% 5-Year OS

71.4% 5-Year OS

Oya et al., 2002 [14]

3/37 Leptomeningeal relapses

1/10 Leptomeningeal relapses

OS, overall survival; EFS, event-free survival; PFS, progression-free survival.