title: Influence of boost radiotherapy in patients with ductal carcinoma in situ breast cancer: a multicenter, retrospective study in Korea (KROG 11-04).
abstract: To estimate the effect of boost radiotherapy on local recurrence-free survival (LRFS) in patients with ductal carcinoma in situ (DCIS) breast cancer. We included patients from nine institutions who met the following criteria: having Tis, age 18 years or older, having breast conserving surgery (BCS) and radiotherapy within 12 weeks after surgery. From 1995 through 2006, 728 patients were analyzed retrospectively by the Korean Radiation Oncology Group. All patients received whole-breast radiation therapy (WBRT) after BCS. 232 patients (31.9 %) also received boost radiation therapy (RT) (median 10 Gy). After median follow-up of 82 months, 5-year LRFS was 98.4 % and 10-year LRFS was 95.8 % for all patients. There was no statistically significant difference of LRFS between the boost and no-boost groups. Nineteen (2.6 %) patients had ipsilateral breast recurrences, including 12 of invasive recurrence and 7 DCIS. The presence of the HER2 receptor was associated with more invasive recurrences. Nine (1.2 %) patients developed contralateral breast cancer, including six invasive breast cancer and three DCIS. In the multivariate analysis, only the margin status was a significant prognostic factor for LRFS. Boost RT was not associated with further improvement of local control in DCIS after BCS and WBRT. HER2 receptor-positive patients may need further treatment with the anti-HER2 agents.
authors.affiliation: Department of Radiation Oncology, Dongsan Medical Center, Keimyung University School of Medicine, 56 Dalseong-Ro, Jung-Gu, Daegu, Korea, jhkim@dsmc.or.kr.
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Kim
authors.forename: Doo Ho
authors.initials: DH
authors.lastname: Choi
authors.forename: Won
authors.initials: W
authors.lastname: Park
authors.forename: Seung Do
authors.initials: SD
authors.lastname: Ahn
authors.forename: Su Ssan
authors.initials: SS
authors.lastname: Kim
authors.forename: Sung Whan
authors.initials: SW
authors.lastname: Ha
authors.forename: Kyubo
authors.initials: K
authors.lastname: Kim
authors.forename: Yong Bae
authors.initials: YB
authors.lastname: Kim
authors.forename: Ji Woon
authors.initials: JW
authors.lastname: Yea
authors.forename: Min Kyu
authors.initials: MK
authors.lastname: Kang
authors.forename: Kyung Hwan
authors.initials: KH
authors.lastname: Shin
authors.forename: Dong Won
authors.initials: DW
authors.lastname: Kim
authors.forename: Ji Hae
authors.initials: JH
authors.lastname: Lee
authors.forename: Chang-Ok
authors.initials: CO
authors.lastname: Suh
mesh_terms: D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local; D018714:Radiotherapy, Adjuvant; D056910:Republic of Korea; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome