Focalized intraoperative irradiation after conservative surgery for early-stage breast cancer

At the European Institute of Oncology we are evaluating intraoperative electron-beam radiation therapy (IOERT) as a sole modality of radiation in selected patients with early-stage breast cancer. Three clinical phases have been developed: a dose-escalation study in order to define the maximum tolerable dose of IOERT a phase II study in order to assess toxicity, and a perspective randomized study which compares standard treatment to IOERT. From July 1999 to February 2001 more than 140 patients have been treated. The IOERT dose of 21 Gy has been reached without severe acute side-effects. Since November 2000, patients with breast cancer up to 2.5 cm diameter, aged more than 48 years, unifocal lesion not close to the skin and not located in the high axillary tail, are randomized to receive, after quadrantectomy, a dose of 21 Gy to the index quadrant or the standard external radiation regimen.