by Gabriella Hochmann
Ductal lavage, a new minimally invasive screening tool is presently undergoing clinical trials. Touted as a "pap smear for the breast," it offers a nonsurgical alternative to other standard breast diagnostic tests.
It is well known that mammography, the most widely used form of screening technology next to breast self examination, can miss up to 15% of breast cancers, particularly in the case of younger women. Ductal lavage, a technique for collecting epithelial cells from the breast milk ducts has been found to aid in the detection of pre-malignant and malignant cells in women with normal mammograms and physical exams.
The procedure is based on the concept that breast cancer most often originates in the epithelial cells (lining) of the milk ductal system and involves a series of molecular changes, with cells moving from normal to abnormal to malignant. The procedure is a two-step one, in which ducts most likely to have abnormal cells are first identified, then cells collected for analysis. A breast pump is used to suction fluid from the nipple. Although the presence of ductal fluid does not necessarily mean anything is wrong, ducts with abnormal cells have been found to be associated with roughly a doubling of breast cancer risk. An anaesthetic is applied to the nipple and a thin, flexible catheter threaded into the duct opening of the nipple. A saline solution is then infused through the catheter into the duct and sucked back out. Cells washed out in the fluid are then collected and analyzed, as normal, atypical or malignant. The multicenter trial has recruited over 500 women determined to be at high risk for breast cancer. Preliminary results show that researchers detected abnormal cells in 15% of women analyzed so far. To date, few side effects have been found. When administered by trained professionals, participants have reported that the 10-15 minute procedure is no more uncomfortable than a mammogram, the sensation described by some as "breast fullness" akin to lactation.
American Cancer Society representatives, while calling the procedure "interesting," question how it would be used— e. g., what would a finding of irregular results mean for treatment options or for any other decisions that had to be made?
Dr. Susan Love, one of the originators of the procedure and co founder of ProDuct Health, a company that markets two medical devices used in the procedure, emphasizes that it is not meant to replace mammography. She believes however that the "snapshot" of what is going on in the breast can provide additional useful information to assist in decision making for high-risk women. As well, she sees the procedure as an important research tool in the study of causation— e. g., do carcinogens and/or pesticides concentrate in the ductal fluid?
A new approach— one that seeks to identify abnormal cells "when they are just thinking about becoming cancer."