title: High risk of in-breast tumor recurrence after BRCA1/2-associated breast cancer.
abstract: The purpose of the study was to compare breast-conserving therapy (BCT) and mastectomy (M) in BRCA1/2 mutation carriers. Women with invasive breast cancer and a pathogenic mutation in BRCA1 or BRCA2 were included in the study (n = 162). Patients treated with BCT (n = 45) were compared with patients treated with M (n = 118). Endpoints were local recurrence as first recurrence (LR), overall survival (OS), breast cancer death, and distant recurrence. Cumulative incidence was calculated in the presence of competing risks. For calculation of hazard ratios and for multivariable analysis, cause-specific Cox proportional hazards regression was used. Compared to M, BCT was associated with an increased risk of LR in univariable analysis (HR 4.0; 95 % CI 1.6-9.8) and in multivariable analysis adjusting for tumor stage, age, and use of adjuvant chemotherapy (HR 2.9; CI 1.1-7.8). Following M, all local recurrences were seen in the first 5 years after breast cancer diagnosis. Following BCT, the rate of LR continued to be high also after the first 5 years. The cumulative incidence of LR in the BCT group was 15, 25, and 32 % after 5, 10, and 15 years, respectively. There were no significant differences between BCT and M for OS, breast cancer death, or distant recurrence. BRCA1/2 mutation carriers treated with BCT have a high risk of LR, many of which are new primary breast cancers. This must be thoroughly discussed with the patient and is an example of how rapid treatment-focused genetic testing could influence choice of treatment.
authors.affiliation: Department of Oncology, Skåne University Hospital, Clinical Sciences, Lund University, Lund, Sweden, martin.nilsson@med.lu.se.
authors.forename: Martin P
authors.initials: MP
authors.lastname: Nilsson
authors.forename: Linda
authors.initials: L
authors.lastname: Hartman
authors.forename: Ulf
authors.initials: U
authors.lastname: Kristoffersson
authors.forename: Oskar T
authors.initials: OT
authors.lastname: Johannsson
authors.forename: Ake
authors.initials: A
authors.lastname: Borg
authors.forename: Karin
authors.initials: K
authors.lastname: Henriksson
authors.forename: Elsa
authors.initials: E
authors.lastname: Lanke
authors.forename: Håkan
authors.initials: H
authors.lastname: Olsson
authors.forename: Niklas
authors.initials: N
authors.lastname: Loman
mesh_terms: D000328:Adult; D019313:BRCA1 Protein / Q000235:genetics*; D024682:BRCA2 Protein / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D006579:Heterozygote; D006801:Humans; D008408:Mastectomy; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009154:Mutation; D015996:Survival Rate; D013548:Sweden
chemical_list: D019313:BRCA1 Protein; C492913:BRCA1 protein, human; D024682:BRCA2 Protein; C551750:BRCA2 protein, human