First spinal axis segment irradiation with spot-scanning proton beam delivered in the treatment of a lumbar primitive neuroectodermal tumour. Case report and review of the literature.

Primary intraspinal primitive neuroectodermal tumour (PNET) is a rare tumour entity. The optimal therapeutic management is unclear but, in general, this tumour is treated with surgery followed by radiotherapy and chemotherapy. Proton beam radiation therapy (PT) offers superior dose distributional qualities compared with X- or gamma rays, as the dose deposition occurs in a modulated narrow zone called the Bragg peak. As a result, organs at risk are optimally speared. Here, we present a patient treated with the first spinal axis segment irradiation using spot-scanning PT with a single field, combined with conventional cranio-spinal axis radiotherapy after surgery and chemotherapy, and an extensive review of the literature outlining the clinical features and treatment modality of spinal PNET.