High-Dose-Rate (HDR) or Pulsed-Dose-Rate (PDR) Perioperative Interstitial Intensity-Modulated Brachytherapy (IMBT) for Local Recurrences of Previously Irradiated Breast or Thoracic Wall Following Breast Cancer

PURPOSE: In patients receiving salvage high-dose-rate (HDR) or pulsed-dose-rate (PDR) brachytherapy for a local recurrence on the chest wall or in the previously treated breast, clinical outcome and benefit were investigated. All patients had previously been treated with full-dose adjuvant external-beam irradiation (EBRT). Disease-free interval after salvage treatment, local tumor control and side effects were analyzed retrospectively. PATIENTS AND METHODS: Between 1996 and 2002, a total of 32 consecutive patients were treated. 13 patients initially treated with mastectomy and postoperative irradiation and 19 patients initially treated with breast-conserving surgery and postoperative irradiation developed a local recurrence. The mean dose of previous radiation therapy was 58 Gy (range, 42-64 Gy), applied by conventional fractionation. After implantation +/- surgery of recurrent disease and CT-based 3-D planning, 15 patients were irradiated with HDR-IMBT (intensity-modulated brachytherapy) with a mean dose of 28 Gy (range, 10-30 Gy, 2 x 2.5 Gy/day at 6-h daily interfraction interval) and 17 patients received PDR-IMBT with a mean dose 30 Gy (range, 10-45 Gy, 5 x 1 Gy/day at 2-h pulse intervals). Four patients underwent additional EBRT using a dose of 24-40 Gy electrons. Treatment was performed only on working days. RESULTS: After a mean post-implant follow-up of 19 months (range, 1-83 months), no signs of local recurrence were observed in 20 of the 32 patients. In twelve patients, local recurrence occurred after a mean follow-up of 13 months (range, 1-78 months). 20 of the 32 patients experienced an additional systemic progress. In one patient, an EORTC/RTOG grade 3 side effect (ulceration of the skin) was described, which was followed by a local recurrence 12 months posttherapeutically. CONCLUSION: Perioperative interstitial HDR/PDR-IMBT of localized breast or thoracic wall recurrences following previous full-dose EBRT appears to be a meaningful salvage treatment with acceptable toxicity.