Efficacy of radiation boost after breast-conserving surgery for breast cancer with focally positive, tumor-exposed margins. (12th March 2020)

• Record Type: Journal Article
• Authors: Suzuki, Ryoko; Yoshida, Masahiro; Oguchi, Masahiko; Yoshioka, Yasuo; Tokumasu, Kenji; Osako, Tomo; Ono, Shinji; Ueno, Takayuki; Miyagi, Yumi
• Is Part Of: Journal of radiation research. Volume 61:Number 3(2020:May)
• Page Start: 440
• Page End: 446
• Publication Date: 2020-03-12
• Subjects: breast-conserving surgery -- whole-breast radiation therapy -- tumor-exposed margin -- tumor bed boost -- ductal carcinoma in situ -- invasive breast cancer; Radiology, Medical -- Periodicals; Radiobiology -- Periodicals; Radiation -- Periodicals; 616.0757
• DOI: 10.1093/jrr/rraa005
• Languages: English
• ISSNs: 0449-3060

Abstract

Abstract: Many patients with positive margins following breast-conserving surgery (BCS) undergo re-excisions that aim to remove residual disease from the breast, which brings a tremendous emotional burden in addition to financial consequences. We sought to determine whether re-excisions could be safely avoided without compromising local control and survival by using whole-breast radiation therapy (WBRT) with a tumor bed boost in patients with early-stage breast cancer with focally positive, tumor-exposed margins after BCS. All patients with ductal carcinoma in situ (DCIS) and/or invasive breast cancer (IBC) who had pathologically tumor-exposed margins following BCS, without re-excision and treated with WBRT with tumor bed boost between March 2005 and December 2011, were included. The radiotherapy consisted of WBRT at a dose of 50 Gy in 25 fractions, followed by a tumor bed boost with an additional dose of 16 Gy in eight fractions. A total of 125 patients fulfilled the eligibility criteria; of the 125 patients, 1 had bilateral breast cancer, resulting in 126 cases. Invasive disease was found in 102 (81%) cases and purely ductal carcinoma in situ (DCIS) disease in 24 (19%) cases. The 10-year ipsilateral breast tumor recurrence (IBTR) -free survival, progression-free survival (PFS), and 10-year overall survival (OS) rates were 95%, 92.5% and 96%, respectively. Patients with early-stage breast cancer who receive BCS and have focally positive, tumor-exposed margins can avoid re-excision by undergoing WBRT followed by a sufficient dose of tumor bed boost, without negatively impacting local control and survival.