Systemic therapy for breast cancer and risk of subsequent contralateral breast cancer in the WECARE Study

Rikke Langballe; Lene Mellemkjær; Kathleen E Malone; Charles F Lynch; Esther M John; Julia A Knight; Leslie Bernstein; Jennifer Brooks; Michael Andersson; Anne S Reiner; Xiaolin Liang; Meghan Woods; Patrick J Concannon; Jonine L Bernstein; WECARE Study Collaborative Group

doi:10.1186/s13058-016-0726-0

Back

Systemic therapy for breast cancer and risk of subsequent contralateral breast cancer in the WECARE Study

Journal article

Open access

Systemic therapy for breast cancer and risk of subsequent contralateral breast cancer in the WECARE Study

Rikke Langballe, Lene Mellemkjær, Kathleen E Malone, Charles F Lynch, Esther M John, Julia A Knight, Leslie Bernstein, Jennifer Brooks, Michael Andersson, Anne S Reiner, …

Breast cancer research : BCR, Vol.18(1), pp.65-65

07/12/2016

DOI: 10.1186/s13058-016-0726-0

PMCID: PMC4940926

PMID: 27400983

Files and links (1)

url

https://doi.org/10.1186/s13058-016-0726-0View

Published (Version of record) Open Access

Abstract

Treatment with tamoxifen or chemotherapy reduces the risk of contralateral breast cancer (CBC). However, it is uncertain how long the protection lasts and whether the protective effect is modified by patient, tumor, or treatment characteristics. The population-based WECARE Study included 1521 cases with CBC and 2212 age- and year of first diagnosis-matched controls with unilateral breast cancer recruited during two phases in the USA, Canada, and Denmark. Women were diagnosed with a first breast cancer before age 55 years during 1985-2008. Abstraction of medical records provided detailed treatment information, while information on risk factors was obtained during telephone interviews. Risk ratios (RRs) and 95 % confidence intervals (CIs) for CBC were obtained from multivariable conditional logistic regression models. Compared with never users of tamoxifen, the RR of CBC was lower for current users of tamoxifen (RR = 0.73; 95 % CI = 0.55-0.97) and for past users within 3 years of last use (RR = 0.73; 95 % CI = 0.53-1.00). There was no evidence of an increased risk of estrogen receptor-negative CBC associated with ever use of tamoxifen or use for 4.5 or more years. Use of chemotherapy (ever versus never use) was associated with a significantly reduced RR of developing CBC 1-4 years (RR = 0.59; 95 % CI = 0.45-0.77) and 5-9 years (RR = 0.73; 95 % CI = 0.56-0.95) after first breast cancer diagnosis. RRs of CBC associated with tamoxifen or with chemotherapy use were independent of age, family history of breast cancer, body mass index and tumor characteristics of the first breast cancer with the exception that the RR of CBC was lower for lobular histology compared with other histologies. Our findings are consistent with previous studies showing that treatment with tamoxifen or chemotherapy is associated with a lower risk of CBC although the risk reduction appears to last for a limited time period after treatment is completed.

United States - epidemiology

Risk Assessment

Humans

Middle Aged

Risk Factors

Antineoplastic Combined Chemotherapy Protocols - adverse effects

Breast Neoplasms - drug therapy

Case-Control Studies

Neoplasms, Second Primary - epidemiology

Neoplasms, Second Primary - etiology

Young Adult

Canada - epidemiology

Breast Neoplasms - pathology

Denmark - epidemiology

Adult

Female

Aged

Odds Ratio

Neoplasms, Second Primary - pathology

Population Surveillance

Breast Neoplasms - epidemiology

Details

Title: Subtitle: Systemic therapy for breast cancer and risk of subsequent contralateral breast cancer in the WECARE Study
Creators: Rikke Langballe - Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen, Denmark
Lene Mellemkjær - Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen, Denmark. lene@cancer.dk
Kathleen E Malone - Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Charles F Lynch - University of Iowa, Iowa City, IA, USA
Esther M John - Department of Health Research and Policy (Epidemiology) and Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA
Julia A Knight - University of Toronto, Dalla Lana School of Public Health, Toronto, Canada
Leslie Bernstein - Beckman Research Institute of the City of Hope, Duarte, CA, USA
Jennifer Brooks - University of Toronto, Dalla Lana School of Public Health, Toronto, Canada
Michael Andersson - Department of Oncology at Rigshospitalet, Copenhagen, Denmark
Anne S Reiner - Memorial Sloan Kettering Cancer Center, New York, NY, USA
Xiaolin Liang - Memorial Sloan Kettering Cancer Center, New York, NY, USA
Meghan Woods - Memorial Sloan Kettering Cancer Center, New York, NY, USA
Patrick J Concannon - University of Florida Genetics Institute, Gainesville, FL, USA
Jonine L Bernstein - Memorial Sloan Kettering Cancer Center, New York, NY, USA
WECARE Study Collaborative Group
Resource Type: Journal article
Publication Details: Breast cancer research : BCR, Vol.18(1), pp.65-65
DOI: 10.1186/s13058-016-0726-0
PMID: 27400983
PMCID: PMC4940926
NLM abbreviation: Breast Cancer Res
ISSN: 1465-5411
eISSN: 1465-542X
Publisher: England
Grant note: R01 CA129639 / NCI NIH HHS R01 CA097397 / NCI NIH HHS U01 CA083178 / NCI NIH HHS P30 CA008748 / NCI NIH HHS P30 CA086862 / NCI NIH HHS R01 CA114236 / NCI NIH HHS
Language: English
Date published: 07/12/2016
Academic Unit: Epidemiology
Record Identifier: 9983995162502771

Metrics

22 Record Views

37 Times Cited - Web of Science