carcinoma

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Related to apocrine carcinoma: sebaceous carcinoma, apocrine adenoma

neoplasm

neoplasm or tumor, tissue composed of cells that grow in an abnormal way. Normal tissue is growth-limited, i.e., cell reproduction is equal to cell death. Feedback controls limit cell division after a certain number of cells have developed, allowing for tissue repair but not expansion. Tumor cells are less responsive to these restraints and can proliferate to the point where they disrupt tissue architecture, distort the flow of nutrients, and otherwise do damage.

Tumors may be benign or malignant. Benign tumors remain localized as a discrete mass. They may differ appreciably from normal tissue in structure and excessive growth of cells, but are rarely fatal. However, even benign tumors may grow large enough to interfere with normal function. Some benign uterine tumors, which can weigh as much as 50 lb (22.7 kg), displace adjacent organs, causing digestive and reproductive disorders. Benign tumors are usually treated by complete surgical removal. Cells of malignant tumors, i.e., cancers, have characteristics that differ from normal cells in other ways beside cell proliferation. For example, they may be deficient in some specialized functions of the tissues where they originate. Malignant cells are invasive, i.e., they infiltrate surrounding normal tissue; later, malignant cells metastasize, i.e., spread via blood and the lymph system to other sites.

Both benign and malignant tumors are classified according to the type of tissue in which they are found. For example, fibromas are neoplasms of fibrous connective tissue, and melanomas are abnormal growths of pigment (melanin) cells. Malignant tumors originating from epithelial tissue, e.g., in skin, bronchi, and stomach, are termed carcinomas. Malignancies of epithelial glandular tissue such as are found in the breast, prostate, and colon, are known as adenocarcinomas. Malignant growths of connective tissue, e.g., muscle, cartilage, lymph tissue, and bone, are called sarcomas. Lymphomas and leukemias are malignancies arising among the white blood cells. A system has been devised to classify malignant tissue according to the degree of malignancy, from grade 1, barely malignant, to grade 4, highly malignant. In practice it is not always possible to determine the degree of malignancy, and it may be difficult even to determine whether particular tumor tissue is benign or malignant.

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carcinoma

[‚kärs·ən′ō·mə]
(medicine)
A malignant epithelial tumor.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

carcinoma

Pathol
1. any malignant tumour derived from epithelial tissue
2. another name for cancer
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
Apocrine carcinoma as triple-negative breast cancer: novel definition of apocrine-type carcinoma as oestrogen/progesterone receptor negative and androgen receptor positive, invasive ductal carcinoma.
Invasive apocrine carcinoma of the breast: a long-term followup study of 34 cases.
Apocrine differentiation in invasive pleomorphic lobular carcinoma with in situ ductal and lobular apocrine carcinoma: a case report.
Although in daily diagnostic practice, it may be difficult to assess, Seidman et al (10(p2351)) point out that "a nucleus that has a diameter of 1.73 times a neighboring nucleus has an area 3 times this nucleus." In addition, they highlight that the most striking atypical feature is the nucleolar enlargement, not the nucleolar prominence per se, because distinct nucleoli are almost invariably present in apocrine change, and markedly pleomorphic enlarged nuclei are usually present in apocrine carcinomas. (10) Nuclear hyperchromasia and irregularities of the nuclear membrane may be affected by fixation artifacts, stain intensity, and section thickness; hence, they are not always reliable features.
[3] Prognosis of apocrine carcinoma of breast is similar to and that of the glycogen rich and sebaceous carcinoma is worse than invasive ductal carcinomas.
Apocrine carcinoma as triple-negative breast cancer: novel definition of apocrine-type carcinoma as estrogen/progesterone receptor-negative and androgen receptor-positive invasive ductal carcinoma.
Also identified were 2 cases (4%) of basal cell carcinoma (BCC), 2 cases (4%) of sebaceous carcinomas, and rare cases (n = 1 each) of apocrine carcinoma, spiradenocarcinoma, and adenoid cystic carcinoma (2% each).
The tumor cells may show prominent granular eosinophilic cytoplasm focally and higher nuclear grade, resembling apocrine carcinoma morphology.
Oestrogen receptor-beta1 but not oestrogen receptor-betacx is of prognostic value in apocrine carcinoma of the breast.
The tumor cells of the case of invasive apocrine carcinoma had abundant eosinophilic cytoplasm and large atypical nuclei and were arranged in tubular structures infiltrating fibrous tissue (Figure 12).
In our study, the mean age of patients with histological types of breast cancer were >55 years except in cases of apocrine carcinomas. The genetic background and low number of cases in our study might be the reason for the difference among those different types of carcinomas.