Total body irradiation for treatment of haematological diseases

Summary The present status of total body irradiation (TBI) as a part of the treatment of haematological diseases was discussed during a separate symposium at the 5th Annual ESTRO meeting at Baden-Baden. The experimental techniques applied in Europe, the dosimetry for TBI, the radiobiological aspects and the late effects after TBI have been reviewed. For specific geometries, precautions have to be taken to avoid increased dose contributions at the skin due to electrons scattered from the wall behind the patient. CT data can be useful for the individualisation of the exposure regimen of patients with extreme variations in lung anatomy or lung density. An appreciable number of centres apply in vivo dosimetry, however, special care is needed for the correct interpretation of the dosimeter readings. A number of late effects, including induction of cataract and secondary tumours has been observed after TBI. The techniques applied for TBI at the various centres and the temporal administration of the dose show wide variations. At present, the patient material is too heterogeneous to draw any conclusion about an optimum schedule for a TBI regimen. Further cooperation between clinicians, radiobiologists and radiation physicists has to be established to achieve consistency and further improvement of the results after TBI.