CHICAGO—The debate on mammographic screening of women in their 40s was propelled back into center stage here at the Radiological Society of North America's Scientific Assembly and Annual Meeting.
Screening younger women has been controversial, with 2009 guidelines from the US Preventive Services Task Force (USPSTF) recommending against routine mammography screening for average-risk women in their 40s. And this past November, a Canadian task force issued similar guidelines recommending against screening of women in this age group.
But the new study reported here (Abstract SST01-01) showed that mammograms were just as likely to spot invasive breast cancers and lymph node metastases in women in their 40s with no family history of breast cancer as in their counterparts with a family history.
Patients without a family history represent the “average-risk” women cited by USPSTF, said Stamatia V. Destounis, MD, Managing Partner at Elizabeth Wende Breast Care, an outpatient facility in Rochester, NY.
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“Since there's no difference in the rate of invasive breast cancer for women in their 40s whether they have a history of breast cancer or not, the recommendation should be that women in their 40s have screening mammography yearly,” she said at a news conference at the meeting.
In the retrospective study of 1,071 breast cancer patients in their 40s, a total of 64.0% of those with no family history of breast cancer had invasive disease, compared with 63.2% of those with family history, a nonsignificant difference, she said.
Additionally, similar percentages of patients with and without familial histories had metastases to the lymph nodes: 29.4% vs 31.3%, again a nonsignificant difference, the study showed.
Dr. Destounis and colleagues reviewed the medical records of all 1,071 women in their 40s who had screening mammograms at their medical center between 2000 and 2010. A total of 373 were diagnosed with breast cancer as a result of screening.
Most of the women with cancer (228 patients, or 61%) did not have a family history of the disease. Of the 39% who did have a family history, about one-third reported premenopausal cancer in a first-degree relative, one-third reported postmenopausal cancer in a first-degree relative, and the others reported premenopausal or postmenopausal cancer in a second- or third-degree relative.
There was no significant difference in the rates of personal history of breast cancer: 5% of those with a family history versus 7% of those without a family history.
A total of 71 (31.1%) patients without a family history in whom breast cancer was detected had a mastectomy vs 54 (37.5%) of those with a history, a nonsignficant difference. All the other women, with the exception of the one patient without a family history who declined surgery, had a lumpectomy.
A criticism of screening younger women is that “you find small cancers that will never be a problem. But we found a considerable number of invasive breast cancers that can't wait,” Dr. Destounis said.
Dr. Destounis receives funding to conduct clinical research from several breast imaging companies, including Siemens AG and Hologic. The current study was independently funded without company support.
The frequency of screening mammograms—and the appropriate age to begin them — has been controversial since the USPSTF recommended that women routinely get screening mammograms every other year starting at age 50.
The task force said the decision to start regular mammograms before age 50 should be an individual choice based on each woman's situation. But overall, the benefits of screening all women in their 40s do not outweigh the risks, including that of having to undergo unnecessary biopsies, the task force said.
A recent study appeared to support that position, finding that biennial screening reduces false-positive recalls by about one-third, compared with yearly mammograms (Hubbard RA et al Ann Intern Med 2011;155:481-492).
But other recent research suggests that annual mammography prevents more than 2,000 deaths per year among women diagnosed in their 40s in the United States (Berg WA JAMA 2010;303:168-169), Dr. Destounis said.
Meanwhile, both the American Cancer Society and the National Cancer Institute continue to recommend annual screening beginning at age 40. The result: Confusion among patients and physicians alike.
“All these task forces are coming out saying not to screen, not to do breast self-exam, not to do clinical breast exam [if you're in your 40s]—It's ridiculous,” she said.
Dr. Destounis said her center “had to do advertising and education and community events trying to offset the harm caused by the US Task Force. Primary care physicians were telling [younger] patients not to come in for a screening mammogram, so the patients thought they didn't have to come in for a screening mammogram. But they do need to come in,” she said.
Other Breast Radiologists at the Meeting Agreed
A random sampling of about 10 breast radiologists at the meeting showed that most agreed.
Echoing the sentiments of many interviewed, Nilza Kallos, MD, Head of the Breast Health Center & Diagnostic Ultrasound in Miami, said, “The task force left people confused. I sent all my referring physicians and patients a letter explaining—topic by topic—the dangers of not doing mammograms before 40 or every two years after 50,” she said.
Gary J. Whitman, MD, Professor of Radiology in the Section of Breast Imaging at MD Anderson Cancer Center, said, “I've heard at the meeting that screening might be down five to 10 percent this year because of the task force and the economy.
“But there are very few mammographers who feel differently about the need to screen all women at 40 years of age,” he said.
Priscilla Slanetz, MD, MPH, Director of Breast Imaging Research and Education at Beth Israel Deaconess Medical Center, said, “The controversy about the task force has created more confusion for women on whether or not they should be undergoing screening.
“It's concerning to me—a number of years ago I looked at mammography rates in different ethnic groups. Whenever this controversy is in the news, the most vulnerable populations are the ones who don't come in,” she said.
Not the Case, Though, with Non-Radiologists
Breast cancer specialists who are not radio-logists, though, were a bit more tempered.
Screening recommendations are aimed at the general population, not the individual patient, noted Claudine Isaacs, MD, Director of the Clinical Breast Cancer Program at Georgetown's Lombardi Comprehensive Cancer Center.
Still, “while there is general agreement on the benefits of mammography in women between the ages of 40 and 50 with a family history of this disease, this study suggests that mammography is equally beneficial in those without a positive family history,” she said.
Edith A. Perez, MD, Director of the Breast Cancer Program and Professor of Medicine in the Division of Hematology/Oncology at the Mayo Clinic in Jacksonville, FL, said, “An overall goal of screening in this decade is to determine whether there are tools to improve selection of patient's who should undergo screening mammography.
“One of the factors that has been considered is whether ascertainment of family history would be useful,” she said. “However, this new and relevant data set appears to negate the impact of assessing family history—[especially] first-generation history—as a method to optimize selection of patients for mammography.”