Nov. 6, 2001 -- For women at high risk of breast cancer, a new procedure could provide early detection of cancerous cells -- long before a tumor would show up on a mammogram or clinical breast exam, according to a new study.
The new procedure, ductal lavage, found abnormal breast cells about three times more often than nipple aspiration, another nonsurgical technique used to detect early signs of cancer, reports William C. Dooley, MD, medical director of the University of Oklahoma Breast Institute. These abnormal cells sometimes change into cancerous cells.
Dooley says researchers have been studying these abnormal breast cells since the 1950s.
"We've known for a long time that these cells are harbingers of more immediate danger," he tells WebMD. "The problem has been that all our regular screening modalities -- mammogram, ultrasound, physical exam -- rarely if ever detect these cells. Ductal lavage now gives us a minimally invasive, more reliable way to search for them."
The study involved 507 women at high risk of developing breast cancer -- including 291 with a history of breast cancer and 199 with other factors that put them at elevated risk -- at 19 centers across the country. The women were, on average, 51 years old. All had mammograms and clinical breast exams showing no evidence of tumors.
All of the women had the nipple aspiration procedure, which extracts fluid from the nipple using a modified breast pump. The fluid is then analyzed for abnormal cells.
The women also had the ductal lavage procedure, in which a very thin catheter is inserted into a milk duct and cells are collected for testing.
Ductal lavage was much more reliable in gathering samples that were sufficient for diagnosis than nipple aspiration, says Dooley. Only 27% of nipple aspiration samples were adequate for diagnosis, but 78% of ductal lavage samples were adequate.
The result: Ductal lavage was three times more successful than nipple aspiration in detecting abnormal cells. Women also tolerated the procedure well, he reports. His study appears in this month's Journal of the National Cancer Institute.
Dooley tells WebMD that ductal lavage may help identify women who would respond well to the breast cancer drug tamoxifen. In a landmark study, women who most benefited from tamoxifen were those who had atypical cells, like those found with ductal lavage. Breast cancer in those women was reduced by 86%, he says.
Who are the high-risk women who could benefit from the test?
Women with cancer in one breast already have a very high risk in the other breast, Dooley says. "By doing lavage, whether it's at their first breast cancer treatment or later on, we can find out if they have premalignant changes. Drug choices can be made during the course of their treatment or follow-up to prevent breast cancer in that remaining breast."
Also, women with a strong family history of breast cancer or genetic markers for it can benefit, he tells WebMD. "The problem with most risk factors, as well as genetic tests for breast cancer risk, they don't tell you what point in life the risk escalates. This procedure tells them about immediate danger."
However, it's not a procedure every woman should seek out, says Debbie Saslow, PhD, director of breast and cervical cancer at the American Cancer Society.
Ductal lavage "is not in the same league as mammogram or clinical breast exam, it's not a general screening tool," she tells WebMD. "It is a tool to help some women who may be at increased risk of breast cancer to further understand their risk, to help them make decisions about treatment."
The majority of women who have had breast cancer have already taken tamoxifen, so they won't derive any benefit from taking it again, says Saslow. "For that woman, there's not much else she can do [after she finds out she has abnormal cells]. Maybe she could be more vigilant about screening, but anyone who has already had breast cancer would be vigilant. Hopefully her doctor is also going to be looking at her mammograms a lot more diligently than the average woman."
Women with a genetic risk for breast cancer may benefit from the information, she says. "For them, ductal lavage may help them make the decision whether to have prophylactic mastectomy, take tamoxifen, or continue with mammograms and clinical examinations."