title: Duration of tamoxifen use and the risk of contralateral breast cancer in BRCA1 and BRCA2 mutation carriers.
abstract: Women with a mutation in BRCA1 or BRCA2 face a lifetime risk of breast cancer of approximately 80 %. Tamoxifen treatment of the first cancer has been associated with a reduction in the risk of a subsequent contralateral cancer. We studied 1,504 women with a known BRCA1 or BRCA2 mutation, 411 women with bilateral breast cancer (cases) and 1,093 women with unilateral breast cancer (controls) in a matched case-control study. Control women were of similar age and had a similar age of diagnosis of first breast cancer as the cases. For each woman who used tamoxifen, the starting and stopping dates were abstracted and the duration of tamoxifen use was calculated. Three hundred and thirty-one women had used tamoxifen (22 %); of these 84 (25 %) had completed four or more years of tamoxifen, the remainder stopped prematurely or were current users. For women with up to 1 year of tamoxifen use, the odds ratio for contralateral breast cancer was 0.37 (95 % CI 0.20-0.69; p = 0.001) compared to women with no tamoxifen use. Among women with 1-4 years of tamoxifen use the odds ratio was 0.53 (95 % CI 0.32-0.87; p = 0.01). Among women with four or more years of tamoxifen use the odds ratio was 0.83 (95 % CI 0.44-1.55; p = 0.55). Short-term use of tamoxifen for chemoprevention in BRCA1 and BRCA2 mutation carriers may be as effective as a conventional 5-year course of treatment.
authors.affiliation: Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Jacek
authors.initials: J
authors.lastname: Gronwald
authors.forename: Andre
authors.initials: A
authors.lastname: Robidoux
authors.forename: Charmaine
authors.initials: C
authors.lastname: Kim-Sing
authors.forename: Nadine
authors.initials: N
authors.lastname: Tung
authors.forename: Henry T
authors.initials: HT
authors.lastname: Lynch
authors.forename: William D
authors.initials: WD
authors.lastname: Foulkes
authors.forename: Siranoush
authors.initials: S
authors.lastname: Manoukian
authors.forename: Peter
authors.initials: P
authors.lastname: Ainsworth
authors.forename: Susan L
authors.initials: SL
authors.lastname: Neuhausen
authors.forename: Rochelle
authors.initials: R
authors.lastname: Demsky
authors.forename: Andrea
authors.initials: A
authors.lastname: Eisen
authors.forename: Christian F
authors.initials: CF
authors.lastname: Singer
authors.forename: Howard
authors.initials: H
authors.lastname: Saal
authors.forename: Leigha
authors.initials: L
authors.lastname: Senter
authors.forename: Charis
authors.initials: C
authors.lastname: Eng
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Weitzel
authors.forename: Pal
authors.initials: P
authors.lastname: Moller
authors.forename: Dawna M
authors.initials: DM
authors.lastname: Gilchrist
authors.forename: Olufunmilayo
authors.initials: O
authors.lastname: Olopade
authors.forename: Ophira
authors.initials: O
authors.lastname: Ginsburg
authors.forename: Ping
authors.initials: P
authors.lastname: Sun
authors.forename: Tomasz
authors.initials: T
authors.lastname: Huzarski
authors.forename: Jan
authors.initials: J
authors.lastname: Lubinski
authors.forename: Steven A
authors.initials: SA
authors.lastname: Narod
mesh_terms: D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D019398:Genes, BRCA1; D024522:Genes, BRCA2; D006579:Heterozygote; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D016609:Neoplasms, Second Primary / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology*; D016017:Odds Ratio; D012307:Risk Factors; D013629:Tamoxifen / Q000009:adverse effects* / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen