carcinoma [kahr″sĭ-no´mah] (pl. carcinomas, carcino´mata)
a malignant new growth made up of epithelial cells tending to infiltrate surrounding tissues and to give rise to metastases. A form of cancer
, carcinoma makes up the majority of the cases of malignancy of the breast, uterus, intestinal tract, skin, and tongue.
(adenoid cystic carcinoma
) carcinoma marked by cylinders or bands of hyaline or mucinous stroma separated or surrounded by nests or cords of small epithelial cells, occurring in the mammary and salivary glands, and mucous glands of the respiratory tract. Called also cylindroma
basal cell carcinoma the most common form of skin cancer, consisting of an epithelial tumor of the skin originating from neoplastic differentiation of basal cells, rarely metastatic but locally invasive and aggressive. It usually occurs as small pearly nodules or plaques on the face of an older adult, particularly on a sun-exposed area of someone with fair skin. It has been divided into numerous subtypes on the basis of clinical and histological characteristics.
basosquamous carcinoma carcinoma that histologically exhibits both basal and squamous elements.
cylindrical cell carcinoma carcinoma in which the cells are cylindrical or nearly so.
a highly malignant germ cell tumor
that is a primitive form of carcinoma, probably of primitive embryonal cell derivation; it usually arises in a gonad
and may be found either in pure form or as part of a mixed germ cell tumor
giant cell carcinoma a poorly differentiated, highly malignant, epithelial neoplasm containing many large multinucleated tumor cells, such as occurs in the lungs.
primary carcinoma of the liver cells with hepatomegaly, jaundice, hemoperitoneum, and other symptoms of the presence of an abdominal mass. It is rare in North America and Western Europe but is one of the most common malignancies in parts of sub-Saharan Africa, Southeast Asia, East Asia, and elsewhere. A strong association seems to exist with chronic hepatitis B virus
carcinoma in si´tu a neoplasm whose tumor cells are confined to the epithelium of origin, without invasion of the basement membrane; the likelihood of subsequent invasive growth is presumed to be high.
medullary carcinoma that composed mainly of epithelial elements with little or no stroma.
a malignant tumor arising in the epithelial lining of the nasopharynx
, occurring at high frequency in people of Chinese descent. The epstein-barr virus
has been implicated as a causative agent.
oat cell carcinoma
a form of small cell carcinoma
in which the cells are round or elongated and slightly larger than lymphocytes; they have scanty cytoplasm and clump poorly.
carcinoma in which there are papillary growths that are irregular in nature arising from otherwise normal tissue; it can occur in the thyroid gland, the breast, or the bladder. Called also papillocarcinoma
carcinoma with a hard structure owing to the formation of dense connective tissue in the stroma. Called also fibrocarcinoma
carcinoma sim´plex an undifferentiated carcinoma.
small cell carcinoma
a common, highly malignant form of bronchogenic carcinoma
in the wall of a major bronchus, occurring mainly in middle-aged individuals with a history of tobacco smoking; it is radiosensitive and has small oval undifferentiated cells. Metastasis to the hilum and to mediastinal lymph nodes is common.
squamous cell carcinoma 1.
carcinoma developed from squamous epithelium
, having cuboid cells and characterized by keratinization
. Initially local and superficial, the lesion may later invade and metastasize.
2. the form occurring in the skin, usually originating in sun-damaged areas or preexisting lesions.
in the lung, one of the most common types of bronchogenic carcinoma
, generally forming polypoid or sessile masses that obstruct the airways of the bronchi. It usually occurs in middle-aged individuals with a history of smoking. There is frequent invasion of blood and lymphatic vessels with metastasis to regional lymph nodes and other sites. Called also epidermoid carcinoma
transitional cell carcinoma a malignant tumor arising from a transitional type of stratified epithelium, usually affecting the urinary bladder.
verrucous carcinoma 1.
a variety of squamous cell carcinoma
that has a predilection for the buccal mucosa but also affects other oral soft tissue and the larynx. It is slow-growing and somewhat invasive.
2. Buschke-Löwenstein tumor, so called because it is histologically similar to the oral lesion.
scaly or platelike.
the pars squamosa, or squamous portion of the temporal bone.
squamous cell carcinoma
a carcinoma arising from squamous epithelium; relatively common, locally invasive and occasionally metastatic. In animals they occur on the conjunctiva, the mouth, salivary duct, stomach, trachea and bronchi, prostate, penis, prepuce, vulva, urinary bladder and skin. See also specific organ locations.
a common histological pattern in neoplastic and hyperplastic epidermal disorders. They are whorl-like patterns of squamoid cells.
affected cells are converted to a squamous stratified type from the surface of which squames are shed.
ocular squamous cell carcinoma
that arising from squamous epithelium and having cuboid cells. Squamous cell carcinoma around the eye, also known as cancer eye, is a common neoplasm in cattle, especially those breeds with little pigment in the eyelids. Sunlight, viruses, skin pigmentation and heredity are all thought to be involved in causing the disease. Lesions begin on the third eyelid, unpigmented eyelid or vascular cornea. They are fungating masses of tissue, usually ulcerated, necrotic and apparently painful. They grow rapidly and commonly invade the local lymph nodes. Similar lesions occur on the eyeball and eyelid of the horse. What makes the cattle disease so remarkable is the high prevalence rate. Called also cancer eye.
Squamous cell carcinomas are among the most common skin tumors in dogs and cats. They are particularly common in sun-exposed areas of skin such as the pinnae, eyelids or noses of white cats. Tumors are locally invasive and slow to metastasize.
the common papilloma in all species except cattle and deer. Composed largely of epithelial tissue in contrast to fibropapillomas but many lesions are intermediate in type.