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Abstracts / 2nd International Symposyum on Organ Sparing Treatment	230
Intraoperative radiotherapy in breast cancer. How do we do it?
E. Hager, E. Forsthuber, F. Pri^^, H.Sabitzer, S.Szalay
Institute ofRadiotherapy and Radio-Oncology, Department of Gynaecology, LKH Klagenfurt, Austria
Intraoperative radiotherapy consists ofirradiating the tumor bed ofbreast cancer during operation. The geographic miss of the tumor bed is a well documented phenomenon in boost irradiation, demanding adequate techniques of high quality boost sehips.
After the tumorectomy including a safety margin of 1 to 2 cm around the palpable tumor, the lateral sides are sutured side by side to be better included into the applicator. The irradiation must be localized on the tumor bed, constituted by the lateral section areas of the tumorectomy. The cross-sections of the applicator are circular with the inner diameters of 3, 4, 5, and 6 cm. The applicator is fixed in the Uimor bed with a foil and is not attached to the collimator of the linear-accelerator. Our operating table is moveable alowing the transfer ofthe patient from the operating room to the radiotherapy treatment room in the best conditions ofasepsis. There, the patient is movedfrom the operating table to the treatment couch. Anaesthetic surveillance ofthe patient is ensured by mobile and fixed monitors during the entire period oftransfer and IORT. The depth dose presciption is done by CT scan ofthe tumor bed. The single dose is 9 Gy with 4 to 12 MeV electrons on the 90% isodose.
After the wound is healed, the patients are treated up to 50 Gy (EBRT). No additional boosting is performed. This is why EBRT is two weeks shorter than without IORT. There where no early complications associated with the use of IORT From 5/1999 to 4/2000 conservative surgery was performed on 20 patients with stage I or II breast cancer in a dedicated IORT facility.
Correspondence to: E. Hager, M.D., Institute of Radiotherapy and Radio-Oncology, Department of Gynaecology, LKH Klagenfurt, A-9020 Klagenfurt, Austria.
Radiol Oncol 2000; 34(3): 223-49.