title: Intracranial germ cell tumours: II. The application of a partial transmission block technique to reduce late morbidity.
abstract: Craniospinal axis (CSA) irradiation may be associated with significant late sequelae. The recognition of the influence of dose per fraction on late sequelae and the radiosensitivity of germ cell tumours (GCT) led to the adoption of a partial transmission block (PTB) technique for patients with intracranial GCTs. The PTB allows a dose differential between the whole cranium (prophylactic area) and the primary site (high-dose area) throughout the CSA prescription. The PTB technique has been used in four patients, two with germinoma and two with non-germinomatous germ cell tumours (NGGCT). All patients received two courses of primary chemotherapy with at least a partial response prior to CSA irradiation with the PTB and a three-field boost to the primary site. There was no prolongation in the overall treatment time. The use of this 'CNS friendly' radiotherapy technique was straightforward and the potential benefit in reducing late sequelae is discussed using two isoeffect methods.
authors.affiliation: Department of Radiotherapy, St Bartholomew's Hospital, London, UK.
authors.forename: D J
authors.initials: DJ
authors.lastname: Sebag-Montefiore
authors.forename: D
authors.initials: D
authors.lastname: Doughty
authors.forename: P N
authors.initials: PN
authors.lastname: Plowman
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001932:Brain Neoplasms / Q000532:radiotherapy*; D016190:Carboplatin / Q000008:administration & dosage; D002648:Child; D003131:Combined Modality Therapy; D016371:Cranial Irradiation / Q000009:adverse effects / Q000379:methods*; D005047:Etoposide / Q000008:administration & dosage; D006801:Humans; D009373:Neoplasms, Germ Cell and Embryonal / Q000532:radiotherapy*; D010871:Pinealoma / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D014750:Vincristine / Q000008:administration & dosage
chemical_list: D014750:Vincristine; D005047:Etoposide; D016190:Carboplatin