Re: Louwman WJ et al. On the rising trends of incidence and prognosis for breast cancer patients diagnosed 1975–2004: a long-term population-based study in southeastern Netherlands. Cancer Causes Control 19:97–106

Abstract

The authors state that a lack of decline in breast cancer incidence within the time period of 1975-2005 in the Eindhoven cancer registry is linked to "a different history in HRT use" in European countries in terms of a lower prevalence and shorter duration of use of menopausal hormones [ 1 ]. We doubt this explanation. At least in Germany, population-based nationally representative data suggest that 80% of current users (age: 40-79 years) of menopausal hormones have been using these therapies for more than 3 years in 2003/ 2004. Among current users of menopausal hormone therapy (MHT) aged 60 years and older, 96.4% had used MHT for more than 3 years [2]. These figures appear to be broadly consistent with a population-based cross-sectional survey conducted in 1997/1998 in one area of the north east of Germany; among women aged 40 and older, 25.1% used MHT for 3-5 years, 22.0% for 61 0 years, and 6.6% for more than 1 0 years [3] . In a further regional population-based study conducted in 2000, a project evolving from one German MONICA center, long-term use of MHT exceeding 10 years, as high as 43%, was self-reported by women aged 50_74 years [4]. Surveys conducted within the framework of the European Prospective Investigation into Cancer and Nutrition 1993-1997 [5] show substantial variation in both prevalence of use (maximum of 55% for long-term use in one German center, different from the study regions mentioned above) and duration of MHT (maximum of 10 years and more in 26% of the Danish cohort) across centers. Further studies from Sweden, Norway, and the UK also suggest substantial though different magnitudes of use of long-term MHT [6-8]. Thus, we doubt that use of MHT in European populations before the publication of results from the Women's Health Initiative trials is substantially different from the pattern of use high prevalence and long-term use in the United States (US). In Germany, use of MHT appeared to have at least equalled both prevalence and duration of use compared to that of the US.