Breast cancer can best be described as a type of cancer where cells abnormally divide and grow in the breast tissue. The site where breast cancer originated can typically be found either in the mammary ducts or the lobules. Cancerous tumors usually grow very slowly; by the time a lump is detectable by self examination; it can already be as much as 10 years old. However, it is important to understand the difference between invasive breast cancer and carcinoma in situ. The following is an overview of the various types of carcinoma in situ as well as invasive breast cancer.
Carcinoma in situ is an abnormal cell growth/development inside either the milk ducts or the lobules without spreading to surrounding tissue, hence the term “in situ” which means “in place”. As long as the abnormal cells remain in the milk ducts or lobules the condition is classified as carcinoma in situ. Ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS) are the two primary sub-categories that we will examine.
Ductal carcinoma in situ (DCIS) occurs in the mammary ducts where abnormal cell growth is found. The excess cells in the mammary ducts are very similar to invasive cancer cells and have the potential to develop into invasive cancer eventually. It is due to this fact that early detection is so vital. Lobular carcinoma in situ (LCIS) occurs when there is abnormal cell growth in the open space of the lobules. LCIS differs from DCIS because of the type of cells that are growing ? they do not have the potential to develop into cancer. However, women with LCIS have a significantly higher risk for developing invasive cancer.
Invasive cancer is when these abnormal cells that form inside the mammary ducts or lobules spread into the surrounding breast tissue. Invasive cancer doesn?t necessarily mean that the disease has spread beyond the breast. If invasive cancer is detected early – when a tumor is still relatively small, it can be successfully treated. However, when the cancer is more advanced, and the tumor is larger, the chance of a successful outcome is reduced. This advanced stage has poorer outcomes because the larger tumor can spread to other organs such as the liver, lungs, and bones.
Upon discovering a lump (by feeling or mammogram), most women suspect it to be breast cancer. This is not usually the case, but the only way to know for sure is to have follow-up tests and/or a biopsy. Follow-up tests provide additional information about the suspicious area by using advanced imaging techniques such as mammograms or ultrasound. A biopsy consists of removing cells from the abnormal area and examining them under a microscope to determine an accurate prognosis.
When a woman finds a lump it is very important to have it checked out; the odds of that lump being invasive cancer is about 20%. She will either need a mammogram or a biopsy. The mammogram will be able to provide more information about the suspicious area. A biopsy will give you and the physician definitive results as to what is causing the lump and whether it is dangerous.