Carcinoma is a term designating any malignant cancer that arises from epithelial cells, meaning the tissue that lines the inner or outer surfaces of the body. Typically, a carcinoma can invade surrounding tissues and organs due to the abnormal multiplication of cells and may metastasize or spread to other sites. The most frequent organ sites of carcinoma are the lungs, breasts, prostate, colon, rectum and pancreas. When it comes to breast cancer, nearly all breast cancers are ductal carcinoma. Ductal carcinoma arises from the ducts of a gland. There are two main types of ductal carcinoma: mammary and pancreatic.
Mammary ductal carcinoma is the most common type of breast cancer in women. Numerous women are diagnosed with this condition every year, worldwide. The main forms of mammary ductal carcinoma are invasive ductal carcinoma and ductal carcinoma in situ. The first form is an infiltrating, malignant and abnormal proliferation of neoplastic cells in the breast tissue, while the second one is a noninvasive neoplasm which still has the potential of being malignant and is confined to the milk ducts (also known as lactiferous ducts). Invasive ductal carcinoma is actually the most common form of invasive breast cancer, with a 55% breast cancer incidence upon diagnosis as of 2004. On the other hand, ductal carcinoma in situ is the most common form of noninvasive breast cancer or pre-cancer in women. When diagnosed with any of the two types of mammary ductal carcinoma, women have a range of treatment options they can choose from.
Asking for one or more medical opinions prior to undergoing any type of carcinoma treatment is a good idea. The prognosis of mammary ductal carcinoma depends on the form that the patient is suffering form. Moreover, the prognosis for invasive ductal carcinoma also depends on its histological subtype, tumor size, presence of cancer in the lymph nodes, histological grade, presence of cancer in small vessels, expression of hormone receptors and of oncogenes. When it comes to ductal carcinoma in situ, the prognosis is quite high. However, if the carcinoma is left untreated, there are 60% chances of it becoming invasive at 40 years follow-up.


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