The association between oral contraceptive use and lobular and ductal breast cancer in young women

Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
International Journal of Cancer (Impact Factor: 5.09). 02/2008; 122(4):936-41. DOI: 10.1002/ijc.23163
Source: PubMed


Recent reports indicate that the incidence of lobular breast cancer is increasing at a faster rate than ductal breast cancer, which may be due to the differential effects of exogenous hormones by histology. To address this issue, we examined whether the relationship between oral contraceptive use and incident breast cancer differs between lobular and ductal subtypes in young women. A population-based sample of in situ and invasive breast cancer cases between ages 20 and 44 were recruited from Atlanta, GA; Seattle-Puget Sound, WA and central New Jersey. Controls were sampled from the same areas by random-digit dialing, and were frequency matched to the expected case age distribution. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using polytomous logistic regression. Among the 100 lobular cancers, 1,164 ductal cancers, and 1,501 controls, the odds ratios for oral contraceptive ever use were 1.10 (95% CI = 0.68-1.78) for lobular cancers and 1.21 (95% CI = 1.01-1.45) for ductal cancers, adjusted for study site, age at diagnosis, and pap screening history. Our results suggest that the magnitude of the association between ever use of oral contraceptives and breast cancer in young women does not vary strongly by histologic subtype. These results are similar to previous studies that report little difference in the effect of oral contraceptive use on breast cancer by histology.

Full-text preview

Available from:
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Fear from increased cancer risk is one of the most significant reasons for low acceptance of reliable contraceptive methods and low compliance. In this review, we included all cohort and case-control studies published in English up to December 2008. They were identified through a search of the literature using Pubmed and EMBASE. Data about breast cancer risk indicate a slightly increased risk among current users of oral contraceptives (OC), an effect which disappears 5-10 years after stopping. Combined OC have a significant protective effect on the risk of ovarian cancer, and the protection increases with duration of use (relative risk decreased by 20% for each 5 years of use). The significant risk reduction has been confirmed for BRCA 1 and 2 mutation carriers. The risk of endometrial cancer is reduced by about 50% in ever users, a benefit which is greater with increasing duration of use. An association has been found between increased risk of cervical cancer and long-term OC use. Current OC use has been associated with an excess risk of benign liver tumours and a modest increased risk of liver cancer. None of large prospective cohort studies with prolonged follow-up has observed an increased overall risk of cancer incidence or mortality among ever users of OC, indeed several have suggested important long-term benefits. Specifically, protective effect of OC can be used as chemoprevention in young women who are BRCA mutation carriers. Women wishing to use combined OC can be reassured that their decision is unlikely to place them at higher risk of developing cancer.
    Preview · Article · Feb 1990 · Human Reproduction Update
  • [Show abstract] [Hide abstract]
    ABSTRACT: Breast cancer is one of the most common malignancies among women. Its incidence is increasing, with 1,151,000 new cases diagnosed every year. Nowadays, it could be considered an epidemic disease because it is estimated that 1-2 women in every 10 will develop this cancer during their lives. Moreover, it is the first cause of death among women worldwide. A lot of work has been carried investigating the causes of breast cancer in the last few years. We have carried out a review of the scientific literature concerning the current situation of risk factors for breast cancer, and their influence in the development of the illness.
    No preview · Article · Oct 2009 · Fuel and Energy Abstracts
  • [Show abstract] [Hide abstract]
    ABSTRACT: Women worldwide have been prescribed medications containing female steroid sex hormones for the past several decades. These medications primarily containing various derivatives of estrogen and/or progesterone have been used for two main purposes, as menopausal hormone therapy (HT) and as contraceptives [primarily in the form of oral contraceptives (OCs)]. Given the central role of hormones in the etiology of breast cancer and the widespread use of these preparations, numerous studies have evaluated the relationship between both HT and various hormonal contraceptives and breast cancer risk. These relationships have been and continue to be of considerable interest to epidemiologists, physicians, and the general population. A summary of this large body of work is provided below including assessments of the impact different types of hormones have on different types of breast cancer.
    No preview · Chapter · Nov 2009
Show more