La radioterapia adiuvante nel carcinoma mammario: Timing e ruolo della IORT

Adjuvant radiotherapy as a standard procedure after conservative surgery on the breast is a subject of discussion by many authors. Based on the radionale that most disease recurrences are observed in the quadrant of the primary tumour, many studies have been conducted and others are still ongoing to evaluate the efficacy of a partial irradiation of the mammary gland with the use of interstitial brachytherapy or external beams of electrons or photons, also with sophisticated techniques (conformational 3-D radiotherapy or IMRT). At the European Institute of Oncology (EIO), it has been decided to use intraoperative radiotherapy (IORT), and a mobile, miniaturized accelerator, delivering electron beams directly on the residual mammary gland during surgery, has been set up in an operating room. The experience of the EIO has been drawn from a phase I study (dose escalation) and a phase II study (to evaluate acute and middle-term toxicity); finally a phase III study has been started, and is still ongoing, to compare the efficacy of partial irradiation by IORT with respect to conventional radiotherapy on the whole breast. The toxicity so far detected is absolutely acceptable, but is necessary to wait for the end of the study in order to have the preliminary data, and for an adequate period of follow-up in order to evaluate the results.