Mortality stats don't reflect screening benefit

Image courtesy of the National Cancer Institute via Creative Commons licensing.

Mortality statistics remain unmoved by breast cancer screenings according to research conducted by the University of Oxford Department of Public Health.

Spanning 40 years, the study considered breast cancer mortality trends in the Oxford region over time following the implementation of the National Health Service Breast Screening Programme, which got its start in 1988. Furthermore, mortality statistics for the whole of England were also scrutinized in the pursuit to prove/disprove program validity.

After pouring over the data, researchers found that factuality in respect to an independent review commissioned by the Department of Health in 2012 — which found a 20 percent relative reduction in mortality due to mammographic screening regimens — had evaporated. At this time, researchers surmised, population-based mortality rates in England do not refract or reflect a clear benefit to breast cancer screening.

This doesn’t mean that individual women cannot reap the benefits of a screening said Toquir Mukhtar, researcher for the Unit of Health Care Epidemiology (UHCE) and leader of the study, but simply that “the effects are not large enough to be detected at the population level."

Moreover, current evaluative methods that aim to quantify the effectiveness of breast cancer screenings in England are riddled with shortcomings, Mukhtar added, as they often do not take into consideration the full breadth of breast cancer treatment improvements, which has significantly widened over the past 20 years.

"Measuring the effectiveness of mammography screening is a fundamental area of concern in countries which have established mammography screening programmes. Clinical trials have indicated that several years have to elapse between the start of screening and the emergence of a reduction in mortality. Yet our data shows that there is no evidence of an effect of mammographic screening on breast cancer mortality at the population level over an observation period of almost 40 years," she concluded.

The study was published in the June 11 edition of the Journal of the Royal Society of Medicine.