Breast cancer development involves the abnormal proliferation of breast tissue cells. As the cancer progresses, cells within the tumor gain invasive properties and begin to migrate into other tissues, eventually travelling to distant sites throughout the body. A traditional symptom of breast cancer, present in many breast cancer cases, is the development of a breast lump. The lump commonly develops due to abnormal growth within the breast duct, forming invasive ductal carcinoma, the most common type of breast cancer, according to BreastCancer.org. Other forms of breast cancer, though, can cause symptoms aside from the usual breast lump.
Invasive Lobular Carcinoma
One form of cancer that does not present with the usual breast cancer symptoms is invasive lobular carcinoma. This form of cancer develops in the lobules, collections of bulb-shaped structures made up of cells that secrete breast milk. Invasive lobular carcinoma does not lead to the formation of a defined breast lump as it progresses. Instead, patients with lobular carcinoma may notice a thickening of the tissue within a localized part of their breast. As the cancer grows, the lump may become larger and eventually cause other symptoms, such as a lump under the arm. MayoClinic.com indicates that lobular carcinoma patients typically receive a combination of breast cancer surgery, drug therapy and radiation to treat their breast cancer.
Paget's Disease
Another form of breast cancer that causes atypical symptoms is Paget's disease, a cancer of the nipple. Paget's disease is characterized by the presence of Paget cells--aggressive cancer cells that colonize within the nipple. Although Paget's disease can co-exist with other forms of cancer that cause breast lumps, Paget's disease itself does not lead to the formation of lumps. Instead, patients with Paget's disease typically experience skin abnormalities on the nipple, such as scaly skin and redness, according to the National Cancer Institute. Paget's disease is very aggressive, and often requires a combination of breast cancer treatments to fight the cancer.
Inflammatory Breast Cancer
Inflammatory breast cancer also does not show the usual symptoms of breast cancer. This form of cancer develops when cancer cells block lymph vessels within the breast, interrupting the normal flow of lymphatic fluid into and out of the breast. Instead of a breast lump, patients with inflammatory breast cancer experience symptoms similar to an infection. The affected breast becomes enlarged and engorged with excess lymph fluid, and the affected breast appears red and feels warm to the touch. Inflammatory breast cancer develops notoriously quickly, and symptoms progress in weeks, according to the National Cancer Institute. Patients with inflammatory breast cancer may receive a combination of surgery, radiation treatment and drug therapies to stop or slow cancer progression.
