Purpose: CyberKnife((R)) (CK) allows stereotaxic irradiation for thoracic tumor thanks to a tracking system which potential is known for lung tumors. This technique has never been used to treat breast tumors but may have a real potential.
Patients and method: In order to define the interest of treating breast tumors with CK, we have conducted a phase I study with a dose escalation, adding CK to neoadjuvant chemotherapy in view of allowing conservative treatment for patients that will not have surgery in first intent. Neoadjuvant chemotherapy includes six cures, including three of docetaxel and three of FEC. CK treatment is made during the second cure of chemotherapy. Two dose levels are delivered in three fractions: 19.5 and 22.5Gy. Surgery is performed six to eight weeks after the last cure. The primary objective is to define tolerance of stereotactic irradiation concomitant with neoadjuvant chemotherapy for breast tumors. Skin toxicity is the limiting criterion of the study. The secondary objectives are both histological response and quality of surgery. Here, we are presenting the preliminary results of the 2-dose level. This study participates in the French national grant called Programme hospitalier de recherche clinique (PHRC).
Results: No skin toxicity of grade I or more have been find. Surgery was performed as conventional and there was no complication. Pathology exams found one complete response, one lymphangitis and one partial response.
Conclusion: These preliminary results seem to be promising but need to be confirmed. We carry on the dose escalation study.