Ductal lavage is not an effective method for detecting breast cancer

August 30, 2017

Ductal lavage--a method used to collect cells from the milk ducts of the breast--has been proposed as a screening tool for cancer detection because ducts that yield fluid were thought to be more likely to contain cancer cells. Interest in the procedure was spurred by a study in which ductal lavage detected cancer in four of 11 women who had shown no previous evidence of a malignancy.

To determine the sensitivity and specificity of ductal lavage in the presence of known breast cancer, Seema A. Khan, M.D., of the Lynn Sage Comprehensive Breast Center and Northwestern Memorial Hospital in Chicago, and colleagues conducted a pilot study in which ductal lavage was performed prior to mastectomy on 44 breasts from 32 women with known cancer and on eight breasts from seven women undergoing prophylactic mastectomy.

The researchers found poor agreement between a cytologic analysis of the cells from ductal lavage and results from looking at breast tissue under the microscope. In breasts with cancer, ductal lavage was able to detect only about half of the cancers, possibly because ducts that contain cancer failed to yield fluid or yielded cells classified as benign or mildly atypical. In addition, ducts that produced fluid did not appear to be related to the cancer in about half of the cancer-containing breasts.

"Although further studies are warranted in women with early lesions, our results and those of others indicate that ductal lavage should not be recommended to high-risk women as a technique to detect cancer earlier than imaging modalities," the authors write.

In an editorial, Carol J. Fabian, M.D., of the University of Kansas Medical Center in Kansas City, and colleagues review several other ongoing studies that are attempting to evaluate the utility of ductal lavage. Based on the results of the current study, they conclude, ductal lavage cannot be considered a sensitive screening tool. "Its use as a risk assessment tool and/or as an indicator of response to [a prevention] intervention is still undergoing evaluation," they write.


"To reduce late-stage cancers, priority should be given to promoting screening among those women without a mammogram within 2 years and improving breast cancer detection at the time of screening," the authors write. "Top priority, however, should be given to reaching unscreened women, especially those who are likely to be older, to have a low annual income, and to have less education, even in organized health plans."

In the editorial, Michael Baum, M.D., of University College London, takes issue with this interpretation of the data and discusses three common sources of possible bias that apply to breast cancer screening. He notes that the effect of increasing the number of women who receive mammograms would be limited because the incidence of interval cancers--cancers diagnosed after a negative screening mammogram--would not change. "[E]fforts directed at improving the socioeconomic status of women in lower strata might indirectly have a greater effect on reducing breast cancer mortality than efforts directed at attaining universal mammography," he writes.