Postmenopausal hormone therapy and ductal carcinoma in situ: A population-based case-control study
ABSTRACT The relationship between hormone therapy (HT) and invasive breast cancer has been extensively investigated, but the relationship between HT and in situ breast cancer has received relatively little attention. We examined the relationship between HT and ductal carcinoma in situ (DCIS) among postmenopausal women who participated in a population-based case-control study in Connecticut, USA.
This analysis included 1179 post-menopausal women (603 controls and 576 cases), who comprised a subset of a population-based case-control study that included all incident cases of breast carcinoma in situ (BCIS) in Connecticut and frequency-matched controls by 5-year age intervals.
We found no association between DCIS and ever use of any HT (adjusted odds ratio (OR)=0.85, 95% confidence interval (CI): 0.65-1.11); of estrogen alone (adjusted OR=0.93; 95% CI: 0.68-1.29) or of estrogen and progesterone (adjusted OR=0.75; 95% CI: 0.52-1.08). There was also no association between DCIS and current use of these hormones. In addition, estimated risk of DCIS did not increase with duration of use of these preparations.
These results add to a small literature that remains inconclusive. To determine whether HT poses risk of in situ breast cancer, larger studies with greater power and precise control of important covariates (e.g., mammography screening) are needed, as are meta-analyses of available data.
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ABSTRACT: Background: The relationship between postmenopausal hormone therapy (HT) and invasive breast cancer has been extensively investigated, but that with breast carcinoma in situ (BCIS) has received relatively little attention. The aim of our present study was to review and summarize the evidence provided by longitudinal studies on the association between postmenopausal HT use and BCIS risk. Methods: A comprehensive literature search for articles published up to May 2012 was performed. Prior to performing a meta-analysis, the studies were evaluated for publication bias and heterogeneity. Relative risk (RR) or odds ratio (OR) values were calculated using 14 reports (8 case-control studies and 6 cohort studies), published between 1986 and 2012. Results: There was evidence of an association between ever postmenopausal estrogen use and BCIS based on a random-effects model (RR = 1.25, 95% confidence interval (CI) = 1.01, 1.55). However, we found no strong evidence of an association between ever postmenopausal estrogen combined with progesterone use and BCIS using a random- effects model (RR = 1.55, 95% CI = 0.95, 2.51). Furthermore, our analysis showed a strong association between " > 5 years duration" of estrogen or estrogen combined with progesterone use and BCIS. Furthermore, current use of any HT is associated with increased risk of BCIS in cohort studies. Additional well-designed large studies are now required to validate this association in different populations.Asian Pacific journal of cancer prevention: APJCP 08/2012; 13(8):3917-25. DOI:10.7314/APJCP.2012.13.8.3917 · 2.51 Impact Factor
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ABSTRACT: PURPOSE: This study aims to measure the impact of HRT use at the time of screening on rates of screen-detected invasive breast cancer (IBC) and ductal carcinoma in situ (DCIS), interval cancers and investigative procedures, within a well-established population-based mammography screening program. METHODS: Using South Australian BreastScreen data from 1998 to 2009 pertaining to 819,722 screening episodes, Poisson regression models were undertaken to estimate the incidence risk ratios (IRR) for various screening outcomes at both the first and subsequent screening rounds, among women who had been using HRT in the 6 months prior to screening compared with those who had not. RESULTS: Current HRT use was associated with increased risk of recall for assessment, biopsy procedures, and breast cancer diagnosis among BreastScreen participants. Risk of screen-detected breast cancer was increased at subsequent screening rounds (IRR = 1.30, 95 % confidence interval 1.18-1.34), but not at women's first screening round (1.05, 0.88-1.25). This increased risk applied to IBC (1.35, 1.27-1.45), but not to DCIS (1.04, 0.89-1.23). Interval cancer risk was elevated among HRT users following both the first screen (1.77, 1.33-2.37) and subsequent screening episodes (1.92, 1.72-2.15). CONCLUSIONS: Increased risks of recall, biopsy rates, screen-detected, and interval cancers among HRT users have important implications for population-based breast cancer screening programs. Our findings support the concept that HRT use may increase the growth of preexisting cancers. Lack of effect on DCIS could imply different etiology or time frames for DCIS and IBC development or increased transition from preinvasive to invasive disease due to HRT use.Cancer Causes and Control 05/2013; DOI:10.1007/s10552-013-0221-1 · 2.96 Impact Factor