'Pill' causes breast cancer?
'Measurable and statistically significant' connection confirmed
A new study from the Mayo Clinic has concluded that there is "a measurable and statistically significant" connection between the pill and pre-menopausal breast cancer, re-enforcing the recent classification of oral contraceptives as Type 1 carcinogens.
That ruling from the International Agency for Cancer Research was supported by the report published in the Mayo Clinic Proceedings this month that comes even as Breast Cancer Awareness Month is being highlighted by pink ribbons, pink soup cans and other promotional devices.
However, the study that found that the risk association was 44 percent over baseline among women who had been pregnant who took oral contraceptives prior to their first pregnancy has been, to a large degree, ignored by many media organizations.
The report, "Oral Contraceptive use as a Risk Factor for Pre-menopausal Breast Cancer: A Meta-analysis," was authored by Dr. Chris Kahlenborn of the Altoona, Pa., Hospital's internal medicine department and others.
Kahlenborn said the results mean that, following standards of informed consent, "women must be apprised of the potential risk of pre-menopausal breast cancer prior to commencing drug use."
The study, which is available online through the Mayo Clinic or at the Polycarp Research Institute, is a meta-analysis of that sometimes-fatal link.
Dr. Kahlenborn focused on the younger, pre-menopausal women who had been on the pill before having their first child. He found 21 of 23 studies showed a connection between the pill and cancer, something that certainly should be alarming women.
However, as Andrea Mrozek, manager of research and communications for the Institute of Marriage and Family Canada, noted in an article.
"Perhaps it is because the pill has long been the darling of feminists – a veritable icon of female empowerment. In some circles, suggesting the pill might kill you is seen as tantamount to issuing a press release that women belong in the kitchen."
Mrozek noted that Queen's University professor Samantha King commented just a few weeks ago that people are not asking "the hard questions about whether we're spending [breast cancer research money] in the right way."
That's because, she noted, incidence rates "have remained stubbornly high … a woman's lifetime risk of breast cancer was one in 22 in the 1940s, but by 2004, it was one in seven."
The evidence already documented "is a trumpet call for further research," Mrozek said. "Until then, young women seeking birth control should be told of the 44 percent increased risk in order to make their own decisions."
Kahlenborn's study looked at dozens of case-control and cohort studies and several other meta-analyses to reach his conclusions.
"Of course things have changed, including OC formulations, the epidemiology of breast cancer, and patterns of use of OCs in the population," the summary noted. "For example, the dosage of estrogen has decreased, new progestins (eg. desogestrel and norgestimate) have been introduced, the hormone-free interval has been shortened, and new delivery systems have become available."
"From the perspective of epidemiology and public health, we must continue to closely follow the epidemiology of OC use and health outcomes, given the widespread use of these agents and their high potential to impact women's health," the report said. "The current study highlights the need for a close evaluation of OC use before first full-term pregnancy since this is an important biologic issue with clear clinical and public health implications."
