Dec 8 2008
A lack of clear-cut, scientific evidence illustrating the benefits of mammography screening in women over 80 has created a trail of controversy leading to a disturbing conclusion about cancer care in America.
"We are ill-prepared from a scientific knowledge perspective to provide cancer health care rationally, ethically, equitably and humanely to the 'booming' older population," say two leading cancer researchers.
In an editorial published online in the Journal of Clinical Oncology ( JCO ), Jeanne S. Mandelblatt , MD, MPH, of Georgetown's Lombardi Comprehensive Cancer Center, and co-author Rebecca Silliman, MD, MPH, PhD, of Boston University Medical Center, address the lack of scientific evidence available regarding cancer screening interventions for older Americans - an issue at the heart of a controversial breast cancer screening study published in the JCO earlier this year.
This study used observational data to provide evidence about the effectiveness of mammography screening in older women, in the absence of clinical trials.
In the current editorial, Mandelblatt and Silliman explore the study's biases, all of which make screening seem more beneficial than it may actually be. If, as the editorial authors conclude, reduction in mortality is the appropriate metric to determine the effectiveness of screening then "at this time, we are left with the fact that there is no evidence that screening women 80 and older with mammography results in reductions in mortality."
Mandelblatt and Silliman commend the study's authors for raising difficult questions in gero-oncology especially when the answers are imperfect, but the authors draw attention to the broader problem related to care of older people.
"With continued gains in life expectancy and increases in cancer incidence with age, clinicians will be caring for an ever-increasing number of older individuals including the oldest old."
Mandelblatt and Silliman recommend an investment in clinical trials specifically to assess cancer screening and treatment for older individuals, in order to strengthen the empirical data available to the medical community when making screening recommendations.
"Without a major shift in emphasis in clinical trials and new investments in understanding the impact of technology and downstream therapy on older populations, we will continue to practice in the context of limited trial evidence."