Related Experiment Video
Updated: Feb 15, 2026

Single-Port Robotic-assisted Transaxillary Breast-conserving Surgery: A Prospective, Single-arm, Non-randomized Phase IIa Clinical Trial
Published on: August 19, 2025
The effect of escalating the boost dose for patients with involved resection margin after breast-conserving surgery
Sunmin Park1, Seung Do Ahn1, Eun Kyung Choi1
1Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Background:
This study aims to investigate the impact of boost dose escalation on ipsilateral breast tumor recurrence (IBTR) in breast cancer patients with involved resection margins following breast-conserving surgery.
Methods:
Between January 1998 and December 2010, 192 patients were treated with a boost dose of over 10 Gy for involved resection margins. We retrospectively analyzed outcomes in 192 patients who underwent whole breast irradiation of 50.4 Gy followed by a median boost dose of 15.0 Gy (range, 12-16 Gy). Boost doses of 12.5 Gy and 15 Gy were delivered to patients with carcinoma in situ and invasive carcinoma, respectively, at the positive margins. We evaluated the impact of the boost dose on the IBTR rate.
Results:
Median follow-up duration was 6.7 years (0.4-15.6 years). The 5-year cumulative risk of IBTR as a first event was 5.0%. IBTR occurred as a first recurrence in 13 of 192 patients. In-boost-field recurrences were found in 11 patients (85%). Five patients (39%) experienced out-of boost field recurrences, and three experienced both types of recurrences. In multivariate analysis, age (<40 years), pT stage, and positive radial resection margin were prognostic factors for IBTR (P = 0.029, P = 0.024 and P = 0.035, respectively).
Conclusions:
A median boost dose of 15 Gy might be insufficient in patients younger than 40 years, with tumor size greater than 2 cm, or with involved radial resection margins. On the other hand, in cases of positive superficial or deep margins, dose-escalated boost or re-excision may not be necessary.
Related Concept Videos
Drug Dosing: Geriatric Patients
Drug Dosing: Obese Patients
What is Conservation Biology?
Conservation of Small Populations
Conserved Binding Sites
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally...
Margin of Error

