Tamoxifen and the risk of ovarian cancer in BRCA1 mutation carriers.
OBJECTIVE
BRCA1 mutation carriers have a high rate of both breast and ovarian cancer. Tamoxifen is a selective estrogen receptor modulator (SERM), which is used for the treatment of primary breast cancer and for the prevention of contralateral breast cancer. Our objective is to assess if tamoxifen treatment is associated with an increase in the subsequent risk of ovarian cancer among women with a BRCA1 mutation.


METHODS
A matched case-control study was performed. Cases were 154 women with ovarian cancer and a previous history of breast cancer. Controls were 560 women with no ovarian cancer and a history of breast cancer. All cases and controls carry a deleterious BRCA1 mutation. Cases and controls were matched for year of birth, age at diagnosis of breast cancer and country of residence. The effect of tamoxifen treatment on the risk of subsequent ovarian cancer was estimated using conditional logistic regression.


RESULTS
The unadjusted odds ratio for ovarian cancer, given previous tamoxifen treatment was 0.89 (95% CI 0.54-1.49, p=0.66). After adjusting for other treatments, the odds ratio was 0.78 (95% CI 0.46-1.33, p=0.36).


CONCLUSIONS
Tamoxifen treatment for breast cancer does not appear to increase the risk of ovarian cancer in BRCA1 mutation carriers.
Vicus
Danielle
D
Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Toronto, Ontario, Canada; Women's College Research Institute, Women's College Hospital, Toronto, Ontario, Canada.
Rosen
Barry
B
Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Toronto, Ontario, Canada.
Lubinski
Jan
J
Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland.
Domchek
Susan
S
Department of Medicine and Genetics, University of Pennsylvania, Philadelphia, PA, USA.
Kauff
Noah D
ND
Clinical Genetics and Gynecology Services, Memorial Sloan-Kettering Cancer Centre, New York, NY, USA.
Lynch
Henry T
HT
Department of Preventive Medicine and Public Health, Creighton University School of Medicine, Omaha, NE, USA.
Isaacs
Claudine
C
Lombardi Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
Tung
Nadine
N
Beth Israel Deaconess Hospital, Boston, MA, USA.
Sun
Ping
P
Women's College Research Institute, Women's College Hospital, Toronto, Ontario, Canada.
Narod
Steven A
SA
Women's College Research Institute, Women's College Hospital, Toronto, Ontario, Canada. Electronic address: steven.narod@wchospital.ca.
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics / Q000517:prevention & control; D016022:Case-Control Studies; D005260:Female; D019398:Genes, BRCA1; D020022:Genetic Predisposition to Disease; D018095:Germ-Line Mutation; D006801:Humans; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000139:chemically induced* / Q000235:genetics*; D013629:Tamoxifen / Q000008:administration & dosage / Q000009:adverse effects*
D013629:Tamoxifen