paediatrics Brussels 17

Childs Nerv Syst

Table 2 Event-free and overall survival estimates from selected radiotherapy series reporting 5 and 10 year outcomes

Series

Time period Patients

5-year EFS 10-year EFS 5-year OS 10-year OS

Akyuz

1972 – 1991 1977 – 1993 1980 – 2000 1961 – 1999 1975 – 1993 1985 – 2002 1980 – 1999

62 92 49 48 40 43 83 32 60

36% 35% 31% 42% 36%

50% 56% 56% 47% 45%

– –

– –

Perilongo

Shu Oya

41% 42% 46% 46% 48% 50% 58% 74%

66% 62% 57% 54% 73% 64% 71% 85%

Pollack

Jaing

–

–

V. Veelan

46%

51%

Robertson 1986 – 1992

–

–

Mansur

1964 – 2000 1997 – 2007

46% 69%

55% 75%

EFS event-free survival, OS overall survival

Merchant

153

patients treated with postoperative fractionated irradiation and focal SRS boost for residual disease were controlled during the same time frame. Jawahar et al. [ 37 ] assessed the role of stereotactic radiosurgery to treat locally progressive ependymoma in adults and children. Their series included 22 patients. The mean tumor volume was 13.7 cm 3 and the mean maximal and median margin doses were 32.3 and 16.1 Gy. With a median follow-up of 21 months, 68% responded to treatment and 41% developed distant metas- tasis. Median survival was 2.2 years. The series by Timmermann et al. [ 42 ] included 55 children with anaplastic ependymoma with 28 treated with GTR and various methods of irradiation. All received chemotherapy. Median follow-up was 38 months; local disease progression occurred in 20 of 53 irradiated patients. The overall survival rate at 3 years after surgery was 75.6%. This value is considered low but includes patients with metastatic disease. The 3-year event-free survival was 66% for localized tumors. Irradiation volume and other clinical factors did not influence survival. McLaughlin et al. [ 43 ] is a classic series where patients with anaplastic tumors received craniospinal irradiation and those with differenti- ated tumors were treated focally. The differences in outcome are difficult to measure based on the high rate of local recurrence. Among 32 intracranial tumors, 21 suffered recurrence at the primary site. Overall and relapse-free survival rates were 51% and 46%, respectively, at 10 years. Tumor site was prognostic for absolute survival ( p = Craniospinal RT

FSRT

Coombs et al. [ 34 ] used fractionated stereotactic radiother- apy to treat intracranial ependymoma in young children. Their success rate was comparable to conventional irradi- ation using a total dose of 54 Gy that was administered in two phases involving, first, the posterior fossa and, second, the tumor bed. Progression-free survival at 5 years was reported to be 64%. Murthy and others [ 35 ] compared dosimetry for posterior fossa ependymoma based on treatment strategies. Target and normal structures contoured included the normal brain, brainstem, cochleae, optic chiasm, hypothalamic axis, supratentorial brain, and the temporal lobes. They found that a six-field technique was optimal irrespective of the size of the target volumes, especially for tumors located anterior to the brainstem. Stereotactic radiosurgery (SRS) has been used adjuvantly after surgery alone or in combination with fractionated external beam irradiation for residual disease [ 36 – 41 ]. Stereotactic radiosurgery has also been used as a salvage treatment with or without addition resection for patients who fail fractionated irradiation. In a series by Lo et al. [ 36 ] that included the aforementioned clinical scenarios, among the five patients treated with surgery and fractionated external beam who experienced treatment failure, three were salvaged with stereotactic radiosurgery using approx- imately 14 Gy with a median follow-up of 30 months. Necrosis was observed and successfully managed. Both SRS

Table 3 Event-free survival estimates for favorable patients from selected radiotherapy se- ries reporting 5-year outcomes

Series

Time period

GTR/patients

5-year OS (%)

5-year EFS (%)

Massimino

1993 – 2001 1980 – 2000 1964 – 2000 1997 – 2007

46/63 30/49 14/60

82 83 84 93

65 61 69 86

Shu

Mansur

GTR gross-total resection, EFS event-free survival, OS overall survival

Merchant

125/153