According to researchers at The University of Texas M. D. Anderson Cancer Center, mammography, the gold-standard for breast cancer screening and early detection, has shown to significantly reduce the risk of being diagnosed with advanced-stage breast cancer in women over 80 years old, an age group currently without clear guidelines for regular screenings.
The study, published recently in the Journal of Clinical Oncology, is the first to specifically assess the screening modality in women older than 80. It’s estimated that approximately 17% of breast cancers are diagnosed in women over 80, and only about one-fifth of women in this group have routine mammograms.
“With an increasing number of people living longer, there’s a real dilemma regarding how best to manage the care of breast cancer patients 80 years of age and older, taking into account both their comorbidities and their account their quality of life,” said Gildy Babiera, MD, associate professor in the department of surgical oncology and the study’s senior author.
Babiera and her colleagues used information from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database for the years 1996-2002, and looked at mammography rates in the 5 years prior to diagnosis. In total, 12,358 women over age 80 were analyzed. Patients were stratified into nonusers (women who did not have mammograms), 49%; irregular users (women who had one or two mammograms), 29%; and regular users (women who had three or more mammograms), 22%. Sixty-eight percent of regular users were more likely to be diagnosed with stage I disease, whereas nonusers and irregular users more often were diagnosed with stage II, III, or IV (56% vs 33%, respectively).
The 5-year survival rate was 94% in regular users, compared to 88% in irregular users and 82% in nonusers. Despite these rates, the researchers were not able to find an increase in overall survival because those getting mammograms were healthier and, therefore, more likely to live longer, said Brian Badgwell, MD, a fellow in the department of surgical oncology and the study’s first author.
“For example, in our study, we showed a 12% decrease in the risk of breast cancer death for each mammogram. However, in the women who received mammograms, we also showed a 12% decrease in non–breast cancer death, thereby showing the bias for women who were healthy and receiving mammograms,” said Badgwell.
Babiera and Badgwell acknowledge their study’s limitations but feel this type of retrospective data may be the best that can be obtained because it’s unlikely a randomized control trial could ever be conducted. They stress that physicians should review each woman’s situation personally to determine if a mammogram is in her best interest.
“Finding breast cancer early in this age group may not result in survival benefit and it may even increase unnecessary angst in elderly women with other ailments. On the other hand, if the woman is otherwise healthy and could be a surgical candidate, should breast cancer be found by a routine mammogram, perhaps she could be offered less invasive treatment and spared from toxic therapies given to women diagnosed with advanced breast cancer,” said Babiera.