Cosmetic outcome in patients with early stage breast cancer after accelerated partial breast irradiation using intraoperative or external beam radiotherapy

• Published in: Clinical and translational radiation oncology Vol. 49; p. 100844
• Main Authors: Gunster, Jetske L.B., Jacobs, Daphne H.M., Mast, Mirjam E., Verbeek-de Kanter, Antoinette, Fisscher, Ursula J., Petoukhova, Anna L., Speijer, Gabrielle, Straver, Marieke, Merkus, Jos, Marijnen, Corrie A.M., Scholten, Astrid N.
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01-11-2024; Elsevier
• Subjects: Accelerated partial breast irradiation; Breast cancer; Cosmetic outcome; External beam radiotherapy; Intraoperative electron radiotherapy; Original; Accelerated partial breast irradiation; Intraoperative electron radiotherapy; Breast cancer; External beam radiotherapy; Cosmetic outcome
• ISSN: 2405-6308; 2405-6308
• DOI: 10.1016/j.ctro.2024.100844

•There is limited research on the cosmetic outcome of different PBI techniques.•Several techniques are available for PBI, including IOERT and EB-APBI.•5-year cosmetic outcome was evaluated by patients, physicians and software.•IOERT and EB-APBI yield comparable, satisfactory cosmetic outcomes.
The aim of this study is to evaluate the cosmetic outcome among early stage breast cancer patients who underwent accelerated partial breast irradiation with either intraoperative electron radiotherapy (IOERT) or photon external beam radiotherapy (EB-APBI).
This prospective multicenter cohort study enrolled women aged 60 years and older who underwent breast-conserving therapy. Following breast-conserving surgery, patients were treated with either IOERT or EB-APBI. Cosmetic outcome was evaluated over a 5 year follow-up period using both subjective scoring by patients and physicians, as well as objective scoring using BCCT.core software. Differences between treatments over time were described with mixed model analyses.
A total of 241 patients treated with IOERT and 164 patients treated with EB-APBI were eligible for cosmetic analysis. In both groups, the majority of patients reported a satisfactory cosmetic outcome, with no significant differences between treatments over time (p = 0.538). This was also observed by physicians, with satisfactory outcomes ranging from 94 % (170/181) to 91 % (69/76) over time in the IOERT group and from 93 % (124/133) to 95 % (54/57) in the EB-APBI group (p = 0.579). BCCT.core analysis returned satisfactory cosmetic outcomes in 75 % (54/72) of the IOERT patients at 3 years and in 77 % (20/26) at 5 years. These numbers were 86 % (72/84) and 90 % (36/40) for the EB-APBI patients, with no significant differences between treatment over time (p = 0.834).
Regarding the cosmetic results, IOERT and EB-APBI yield comparable and satisfactory outcomes over 5 years follow-up in the treatment of early stage breast cancer.