Purpose: To evaluate the feasibility and intermediate-term results of conservative surgery, adjuvant chemotherapy, and delayed accelerated partial breast irradiation (APBI) with high-dose-rate brachytherapy.
Methods and materials: Between 2000 and 2007, a total of 26 patients with a median age of 54 years were treated with conservative surgery followed by adjuvant chemotherapy and exclusive high-dose-rate brachytherapy. Inclusion criteria followed the Radiation Therapy Oncology Group 95-17 trial guidelines. The tumor bed was marked at the time of surgery (n = 2) or before brachytherapy (n = 24). The brachytherapy procedure was performed at a median of 22 weeks after surgery. A median of 14 brachytherapy catheters were placed in three to four parallel planes. A dose of 34.0 Gy in 10 b.i.d. fractions given over 5 consecutive days was prescribed to the clinical target volume (CTV90).
Results: After a median followup of 53 months (range, 6.8-81), Radiation Therapy Oncology Group Grade 1-2 events and Grade 3 events were observed in 10 (38.4%) patients and 3 (11.5%) patients, respectively. No Grade 4-5 events were observed. Patients rated their cosmetic result as excellent (37.5%), good (50.0%), fair (8%), or poor (4%) based on the Wazer's Criteria. The 6-year actuarial local, elsewhere in the breast, and distant control rates were 100%, 96.2%, and 96.2%, respectively. Six-year disease-free survival and overall survival were 92.3% and 96.2%, respectively.
Conclusions: Patients undergoing surgery and adjuvant chemotherapy can still be candidates for APBI. Optimal visualization of the internal lumpectomy scar before implantation is mandatory. Cosmetic results may be slightly worse due to the interaction between chemotherapy and APBI, and technical refinements may be needed in this group of patients.