Robotic stereotactic boost in early breast cancer, a phase II trial
Mené sur 28 patientes atteintes d'un cancer canalaire invasif ou d'un cancer lobulaire de stade pT1-2 traité par lumpectomie puis radiothérapie de l'ensemble du sein, cette étude française évalue la toxicité mammaire cutanée d'une radiothérapie stéréotaxique robotique de type "boost"
Purpose : to evaluate the feasibility and toxicity of a single 8Gy-fraction stereotactic boost after whole breast irradiation (WBI) in early breast cancer. The primary aim of this phase II study was to evaluate cutaneous breast toxicity utilizing CTC-AEv4 three months after the boost. Secondary objectives were local control, survival and patient-reported quality of life using the EORTC QLQ-C30 and breast specific EORTC QLQ-BR 23 questionnaires.
Methods and materials : Patients with invasive ductal or lobular, pT1-2 breast cancer treated with lumpectomy with clear margins and pN0 were included. Patients requiring chemotherapy were excluded.
Results : 28 eligible patients received the planned boost and 26 had hormonal therapy. The procedure was technically successful without procedural complications. A median of three fiducials were tracked and 115 beams were used. There were 22 acute grade-1 breast skin toxicities including fibrosis, pain, erythema or pigmentation. There were two acute grade 2 erythemas. Median skin boost dose was inversely correlated with acute skin toxicity (p=0.028). QLQ-C30 scores revealed acute dyspnea and arm symptoms without correlation to the boost dose. Breast symptom QLQ-BR23 scores did not deteriorate while upset by hair loss and systemic side-effects of hormonal therapy were observed. After a median follow-up of 38 months, one patient had in-boost field relapse and there were 5 late grade 1 and 1 grade 2 skin toxicities.
Conclusion : Single-fraction stereotactic boost after conventional WBI in early breast cancer is feasible in minor toxicities. Quality of life and specific breast items showed excellent patient acceptance.
International Journal of Radiation Oncology • Biology • Physics , résumé, 2017