New Diagnostic Tool for Breast Cancer Disappoints
Ductal lavage misses carcinomas in ill women
MONDAY, Oct. 6, 2003 (HealthDayNews) -- One of the first studies to test the effectiveness of a new, minimally invasive procedure to assess risk for breast cancer found the technique largely unsuccessful.
The study included 28 women who were scheduled for mastectomies. All of the women had been diagnosed with either breast cancer or a precancerous condition, suggesting early signs of the disease.
Yet the procedure was unsuccessful in detecting any sign of the disease in more than half of the women.
The procedure is called ductal lavage. Results of the study appear in the November issue of Cancer.
Ductal lavage is a non-invasive procedure that harvests cells that line the mammary duct, and it has been shown to produce better cell samples than existing techniques.
As such, it is hoped that ductal lavage will aid in detecting breast carcinoma in situ (BCIS), which is a malignancy confined to the cells of the mammary ducts. BCIS includes lobular carcinoma in situ (LCIS), a pre-cancerous condition that indicates a high risk for cancer, and ductal carcinoma in situ (DCIS), the most common form of breast carcinoma in situ.
At present, ductal lavage is used only as an adjunct to other risk assessment techniques such as mammograms, and for the time being should stay that way, says study author Dr. Edi Brogi, a pathologist at Memorial Sloan-Kettering Cancer Center in New York City.
"The presence of invasive carcinoma probably did have an effect on the results. It may distort the ducts and limit the diffusion of fluid. But given that all these patients but two had some kind of pretty serious disease, the findings were a little bit unexpected," Brogi says.
"Until we have more definite data, the use of this technique should be limited. It is best used in the context of clinical studies rather than for the management of the patient," she says.
Most important, Brogi says, "This is not a screening test, and even for risk assessment [a clean reading] should not be taken as a sign that a woman doesn't have cancer."
Another breast cancer expert agrees.
"The thinking process is to try to find more non-invasive procedures to help in diagnosing disease or assessing risk, so these kinds of procedures are going to be developed and improve with time. But this [ductal lavage] needs a lot more study," says Dr. Avi Barbasch, an associate clinical professor of oncology at the Mount Sinai Medical Center in New York City.
Ductal lavage involves sucking the nipple with a breast pump and, when the mammary ducts are located by the nipple discharge, inserting a very narrow catheter into the mammary duct to harvest cells in the duct and along the lining of the duct. Patients find it minimally invasive, Brogi says.
For the study, Brogi and her colleagues evaluated ductal lavage in the women scheduled for mastectomies. The procedure was performed in the affected breasts of 22 patients with breast cancer, four with ductal carcinoma in situ; two with lobular carcinoma in situ; and two who had no sign of cancer but were at high risk for the disease.
From the 29 suitable cell samples obtained by ductal lavage from the patients with cancer or the pre-cancerous lobular carcinoma in situ, the procedure failed to find any sign of malignancy. Fourteen of the samples showed some sign of an abnormality, and 15 were categorized as benign. The results, the authors state, confirm that ductal lavage is not useful as a diagnostic tool for screening for breast cancer.
In another study concerning breast carcinoma in situ, researchers at the University of Southern California Keck School of Medicine in Los Angeles found that for women with no family history of breast cancer, the risk of BCIS was 35 percent lower among those who exercised than among those who were physically inactive.
Analyzing data from more than 1,500 women aged 35 to 65, the authors found that those who engaged in regular physical activity such as walking, jogging, bicycling or swimming reduced their risk for the disease by 35 percent.
The study results also appear in the November issue of Cancer.