Carcinoma is a type of cancer 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 generally arises from cells originating in the endodermal 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.
Histological types
- Adenocarcinoma. Features microscopic glandular-related tissue cytology, tissue architecture, and/or gland-related molecular products, e.g., mucin.
- Squamous cell carcinoma. Observable features and characteristics indicative of squamous differentiation (intercellular bridges, keratinization, squamous pearls).
- Adenosquamous carcinoma. Mixed tumor containing both adenocarcinoma and squamous cell carcinoma, wherein each of these cell types comprise at least 10% of the tumor volume.
- Anaplastic (or undifferentiated) carcinoma. High-grade carcinomas that feature cells lacking distinct histological or cytological evidence of any of the more specifically differentiated neoplasms.
- Large cell carcinoma. Composed of large, monotonous rounded or overtly polygonal-shaped cells with abundant cytoplasm.
- Small cell carcinoma. Cells are usually round and are less than approximately 3 times the diameter of a resting lymphocyte and little evident cytoplasm.
Adapted from Wikipedia, the free encyclopedia. Internet. Accessed on May 25, 2016.