Ductal lavage can't pinpoint breast cancer

While many hoped that ductal lavage might provide a means for detecting breast cancer sooner in women at high risk for the disease, a recent study finds that the method isn't as useful as we had hoped.

Researchers performed ductal lavage in the operating room before mastectomy on 44 breasts from 32 women with known cancer and on eight breasts from seven women undergoing prophylactic mastectomy, two with occult malignancy.

They determined that when complete cytologic and histologic data were available and when marked atypia or malignant cells defined a positive cytologic test, sensitivity of ductal lavage was 43% and specificity was 96%. When mild or marked atypia or malignant cells defined a positive cytologic test, sensitivity was 79% and specificity was 64%. Overall, sensitivity for the method was 17% and specificity was 100% (95% CI = 5% to 100%).

The authors of an accompanying editorial point out that while the results of the study indicate that the sensitivity of ductal lavage is too low for it to be used as a screening procedure for the majority of women at risk of breast cancer, a trial comparing the procedure to digital mammography and breast MRI in young, high-risk women with highly dense breasts might be revealing. They also point out that the high specificities reported in the study are difficult to interpret given that only six true breast cancer negatives were included in the study.

An important limitation of ductal lavage is that traditionally it is only performed on ducts producing nipple aspiration fluid (NAF)-and of course a malignancy can exist in a duct that is not aspirated or does not yield fluid. While it can be performed on ducts not producing NAF, the time and expense involved in cannulating all ducts diminishes the feasibility of using the method for early detection and/or risk assessment.

Khan SA, Wiley EL, Rodriguez N, et al. Ductal lavage findings in women with known breast cancer undergoing mastectomy. J Natl Cancer Inst. 2004;96:1510-1517.

Fabian CJ, Kimler BF, Mayo MS. Ductal lavage for early detection-what doesn't come out in the wash? J Natl Cancer Inst. 2004;96:1488-1489.