A report of data from the National Cancer Institute?s Surveillance Epidemiology and End Results (SEER) database published in the New England Journal of Medicine, suggests that a decline in breast cancer incidence may be caused by a drop in hormone therapy use during the same time period.
Wyeth Pharmaceuticals, a division of Wyeth (NYSE:WYE), cautions against drawing this conclusion for the following reasons:
The SEER data and prescription data for 2004 cast doubt on the authors? hypothesis. In their initial presentation in December 2006, the authors reported that the incidence of breast cancer in the United States declined seven percent between 2002 and 2003, and hypothesized that this decrease was attributable to a decline in hormone therapy use during the same time period. The 2004 SEER data show a leveling off in breast cancer incidence, yet the prescription database shows hormone therapy prescriptions continued to drop by more than 20% during the same time period.
The SEER data showed a decline in numerous cancers, and there may be a broader explanation for this trend. For example, breast cancer tumors that do not respond to estrogen also declined in 2003. There have also been declines in other tumor types, such as colon cancer.
SEER is an epidemiological database that collects cancer data. It does not collect other important information such as medicine use, lifestyle or other essential factors. As such, the database cannot be used to conclude a cause-and-effect relationship between invasive breast cancer rates and hormone therapy usage.
“Reports such as this cause confusion,? says Joseph Camardo, M.D., Senior Vice President of Global Medical Affairs for Wyeth Pharmaceuticals. ?The hypothesis put forth in this report does not change what we know about hormone therapy, which is based on data from numerous, more rigorous studies including the Women?s Health Initiative. These randomized trials provide a higher level of evidence on the risk/benefit profile of hormone therapy.?
One possible factor contributing to the decrease in breast cancer incidence reported in 2003 could be a decline in mammography screening during the same time period. If this decline represents a decrease in early cancer detection, it may only become apparent in the coming years as these cancers manifest and are detected at a later more aggressive stage.
?Hormone therapy remains a good health care choice for the appropriate woman seeking the relief of moderate to severe menopausal symptoms, including hot flashes, night sweats and vaginal atrophy, and the prevention of postmenopausal osteoporosis,? adds Dr. Camardo.
Wyeth continues to support the appropriate use of hormone therapy and recommends that it be used at the lowest dose for the appropriate duration consistent with treatment goals and risks for the individual woman. Women experiencing menopausal symptoms are encouraged to speak with a health care professional to determine whether it might be the right treatment option for them. Wyeth urges women to continue to have routine mammography exams as recommended by the American Cancer Society and as advised in product information provided to patients using hormone therapy.