New Breast Cancer Detection Method Involves Testing Nipple Fluid (dateline February 24, 2000)
Several research groups are currently testing a new method for detecting breast cancer that involves analyzing nipple fluid expressed from the breast. Nipple aspirate fluid, may be drawn out of the breast using a modified breast pump and then studied under a microscope to determine whether cancerous cells and other markers for breast cancer are present. In the most recent study on nipple fluid, researchers found that women with large breast tumors and women whose breasts were surgically removed by mastectomy were likely to have cancerous cells in their nipple fluid. If further research continues to be positive, nipple fluid analysis could become a reliable screening tool for breast cancer.
The idea of testing fluid from the nipple was first suggested in the 1950s by Dr. Papanicolaou, the physician who developed the Pap smear to test for cervical cancer. Nipple aspirate fluid contains several cells and proteins that may be analyzed for the presence of disease. One protein, PSA (protein-specific antigen) is secreted from the breast ducts—the origin of most breast cancers, said Edward Sauter, MD, PhD, lead researcher of a nipple aspirate fluid study at Thomas Jefferson University in Philadelphia. Researchers were reluctant at first to develop a nipple fluid analysis test because they previously believed that PSA was only produced in the male prostate gland. However, recent research has shown that PSA is also present in the breast and is associated with an increased breast cancer risk.
Analyzing nipple fluid can be difficult because few women naturally discharge fluid from their breasts on a regular basis. However, researchers at the University of California at Los Angeles (UCLA) have been experimenting with a new technique to obtain the fluid. Women perform breast massage by placing their hands flat around the base of the breast and squeezing down toward the tip of the nipple while a technologist uses a breast pump (similar to those used by nursing mothers to express milk) to aspirate the fluid. The research group, led by Susan Love, MD, a breast surgeon at UCLA, is also in the process of developing a rapid analysis test of the nipple fluid. Using the breast massage/pump combination technique, researchers were able to successfully obtain nipple fluid from more than 80% of the 60 volunteers from clinics at UCLA and the Olive View Medical Center in Los Angeles.
According to Robert Smith, PhD, director of cancer screenings for the American Cancer Society (ACS), Dr. Sauter’s research group has been able to aspirate nipple fluid from nearly all of the women in their study. Dr. Smith said that the low cost and easy technique of expressing nipple fluid with a pump should give way to further research. Presently, several new studies at Thomas Jefferson University are analyzing nipple fluid in women with no symptoms of breast cancer.
Currently, x-ray examination of the breasts with mammography is the only method approved by the U.S. Food and Drug Administration (FDA) to screen for breast cancer in asymptomatic women (women with no symptoms or signs of breast cancer). Any new breast cancer screening tool must be at least as effective as mammography in detecting breast abnormalities (mammography is able to detect approximately 85% of breast cancers). Surgeons must also be able to perform a breast biopsy on the patient to determine whether the suspicious area is cancerous or benign (non-cancerous) based on the findings of the exam. Since nipple fluid analysis is unable to pinpoint the exact location of the cancer in the breast, additional breast imaging, such as mammography or ultrasound, would have to be performed before a biopsy could be done. Nevertheless, researchers call nipple fluid analysis a promising new development in breast cancer detection.
- The February 22, 2000 ACS News Today report, "Breast Cancer Detection Method Holds Promise," is available at http://www2.cancer.org/zine/dsp_StoryIndex.cfm?fn=001_02222000_0
- The December 14, 1999 Doctor’s Guide report by Robert Carlson, "Nipple Fluid Can Detect Breast Cancer," is available at http://www.pslgroup.com/dg/1508c6.htm
- To learn more about nipple discharge, a common breast complaint which may or may not indicate breast cancer, please visit http://www.imaginis.com/breasthealth/nipple.asp