Carcinome

Carcinoma is a malignancy that develops from epithelial cells. Specifically, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that arises from cells originating in the endodermal, mesodermal or ectodermal germ layer during embryogenesis. Carcinomas occur when the DNA of a cell is damaged or altered and the cell begins to grow uncontrollably and become malignant. It is from the καρκίνωμα (itself derived from karkinos meaning crab).Oxford English Dictionary, 3rd edition, s.v. As of 2004, no simple and comprehensive classification system has been devised and accepted within the scientific community. Traditionally, however, malignancies have generally been classified into various types using a combination of criteria, including: The cell type from which they start; specifically: Epithelial cells ⇨ carcinoma Non-hematopoietic mesenchymal cells ⇨ sarcoma Hematopoietic cells Bone marrow-derived cells that normally mature in the bloodstream ⇨ leukemia Bone marrow-derived cells that normally mature in the lymphatic system ⇨ lymphoma Germ cells ⇨ germinoma Other criteria that play a role include: The degree to which the malignant cells resemble their normal, untransformed counterparts The appearance of the local tissue and stromal architecture The anatomical location from which tumors arise Genetic, epigenetic, and molecular features Adenocarcinoma (adeno = gland) Refers to a carcinoma featuring microscopic glandular-related tissue cytology, tissue architecture, and/or gland-related molecular products, e.g., mucin. Squamous cell carcinoma Refers to a carcinoma with observable features and characteristics indicative of squamous differentiation (intercellular bridges, keratinization, squamous pearls). Conjunctival squamous cell carcinoma Adenosquamous carcinoma Refers to a mixed tumor containing both adenocarcinoma and squamous cell carcinoma, wherein each of these cell types comprise at least 10% of the tumor volume.