Very accelerated partial breast irradiation Phase I–II multicenter trial (VAPBI): Feasibility and early results

• Published in: Brachytherapy Vol. 20; no. 2; pp. 332 - 338
• Main Authors: Guinot, Jose Luis, Gonzalez-Perez, Victor, Meszaros, Norbert, Major, Tibor, Najjari-Jamal, Dina, Gutierrez-Miguelez, Cristina, Santos, Miguel Angel, Smanyko, Viktor, Laplana, Maria, Polgar, Csaba
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-03-2021
• Subjects: APBI; Breast carcinoma; High-dose-rate; Partial irradiation; APBI; Breast carcinoma; High-dose-rate; Partial irradiation
• ISSN: 1538-4721; 1873-1449
• DOI: 10.1016/j.brachy.2020.10.010

This is a multicenter Phase I–II trial endorsed by the GEC-ESTRO Breast Working Group, to analyze if very accelerated partial breast irradiation (VAPBI) with multicatheter interstitial brachytherapy is feasible and safe compared with the standard APBI treatment in 4–5 days for early stage breast carcinomas.
We have included 81 patients with pT1-2 pN0 invasive carcinomas after breast-conserving surgery. Between August 2017 and July 2019, 33 women received high-dose-rate brachytherapy, four fractions of 6.25 Gy in 2–3 days, and 48 patients received three fractions of 7.45 Gy in 2 days. Thirty-six patients were implanted perioperatively and 45 postoperatively. Mean age was 68 (51–90). Free surgical margins were of 2 mm or greater.
Acute effects were 11% dermatitis, 18.5% hematoma, 3.7% infection, and 14.8% pain. At a median followup of 20 months (range 8–35), no relapse has occurred. Pigmentation changes in the entrance and exit of tubes were visible in 16%, but 1 year later, few cases remained. Patients developed G1-2 induration or fibrosis in 18.5% and 2.5%, respectively. No patient developed telangiectasia. The cosmetic outcome was good/excellent in 97.5% and fair in 2.5%.
VAPBI with multicatheter interstitial brachytherapy using four fractions of 6.25 Gy or three fractions of 7.45 Gy in two or 3 days is feasible. No excess has been observed in acute effects. At a mean followup of 20 months, late side effects seem to be similar to standard fractionation. VAPBI in two to 3 days is beneficial for the patients and reduces the workload of the brachytherapy units.