Proton beam radiation (PT) is getting an increasing role in the treatment strategy of complex tumour cases and especially in children. AT PSI, over 100 children were treated so far.

In this analysis we present the evaluation of 62 children treated until the end of 2007 for sarcomatous tumours. Twenty-nine girls and 33 boys were included. Median age at time of diagnosis was 8.1 yrs. (range, 0.1–19.0). The histopathologies were embryonal RMS (n = 24), Chordoma (n = 10), Ewing sarcoma (n = 6), Chondrosarcoma (n = 5), unclassified/undifferentiated RMS (n = 5), Osteosarcoma (n = 4) and miscellaneous. All, but 2 patients had localized disease at time of diagnosis. Tumour site was head and neck in 43 patients, and spine or pelvis in 19 patients. In 50 out of the 62 patients, PT was performed after biopsy or incomplete resection. Forty-four patients had received chemotherapy before or during PT. Median dose of irradiation was 54 Gy (range, 45 – 74 Gy) with 1.8–2.0 Gy fraction dose 4 – 5 times weekly.

Median FU time was 20 months (1.4 – 101). 54 children were still alive at the time of analysis. Twelve patients failed, of them 9 locally and 3 patients at distant site. Acute toxicity was exceeding grade 2 (RTOG/ EORTC) mainly for bone marrow in children with parallel chemotherapy (n = 23). In 6 children skin/mucosal reaction was exceeding grade 2. Late effects were not exceeding grade 2 in the majority of children. One serious adverse event was observed in a very young girl with a parameningeal sarcoma experiencing a lethal ischemia in the pontine area after surgery, chemotherapy and PT.

In the vast majority of patients proton therapy was well tolerated. Local control and survival rates are promising. Longer follow-up time and a greater cohort will help to provide more reliable data.