The National Cancer Institute reports that breast cancer will kill an estimated 39,840 women and 390 men, and lead to more than 200,000 new cancer diagnoses in the United States in 2010. Women with breast cancer develop a lump in their breast, but the presence of a lump does not always indicate breast cancer. Doctors commonly look for indirect signs of malignancy following the discovery of a breast lump to help diagnose breast cancer.
Poorly Defined Tumor Margins
One indirect sign of malignancy is a lack of defined tumor margins. Noninvasive tumors commonly have well-defined edges, since the cells within the tumor do not migrate out into the healthy tissue directly surrounding the tumor. In contrast, malignant tumor cells have gained the ability to invade into neighboring tissue, leading to a cancerous growth with diffuse edges. A report published in the "Indian Journal of Radiology and Imaging" in 2001 indicates that spiculated and poorly defined tumor margins are a major sign of breast lump malignancy.
Enlarged Lymph Nodes
Another indirect sign of breast lump malignancy is the appearance of swollen lymph nodes, which may be visible by medical imaging or palpable during a physical exam. Lymph nodes are small structures that house lymphcytes--the cells that make up part of the immune system. Each breast contains a number of lymph nodes, with still more lymph nodes located above and below the collarbone as well as under the arm. One of the first sites of breast cancer spread is into the lymph nodes, causing lymph node enlargement and matting, according to BreastCancer.org. Since benign breast growths do not have the ability to invade other tissues, the invasion and swelling of lymph nodes serves as an indirect sign of malignancy.
Nipple Retraction
Another indirect sign of malignant breast lesions are changes in the nipple, such as nipple retraction, leading to nipple inversion. Retraction of the nipple can stem from changes in the organization of connective tissue within the breast, or may be due to changes in the duct tissue, such as cancerous growth within the breast ducts. Bermant Plastic Surgery indicates that nipple retraction may occur as an indirect sign of ductal breast cancers, as well as Paget's disease or inflammatory breast cancer, two rare but aggressive forms of breast cancer. Patients with unexplained changes in the appearance of their nipple should receive a clinical breast examination to examine the health of their breasts.
