adenocarcinoma in situ

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ad·e·no·car·ci·no·ma in si·'tu

a noninvasive, abnormal proliferation of glands believed to precede the appearance of invasive adenocarcinoma; reported in the endometrium, breast, large intestine, cervix, and other sites.

adenocarcinoma in situ

a localized growth of abnormal glandular tissue that may become malignant. However, the abnormal cells do not extend beyond the basement membrane. It is most common in the endometrium and in the large intestine.

ad·e·no·car·ci·no·ma in si·tu

(adĕ-nō-kahr-si-nōmă in sitū)
Noninvasive, abnormal proliferation of glands believed to precede the appearance of invasive adenocarcinoma.

adenocarcinoma in situ

Abbreviation: AIS
A localized cluster of malignant appearing cells found in a gland but not yet spreading outside the basement membrane of the gland.
See also: adenocarcinoma
References in periodicals archive ?
PAX8 and PAX2 expression in endocervical adenocarcinoma in situ and high-grade squamous dysplasia.
A case of HPV-negative intestinal-type endocervical adenocarcinoma in situ with coexisting multifocal intestinal and gastric metaplasia.
Adenocarcinoma in situ of the cervix: an underdiagnosed lesion.
The cytologic diagnosis of adenocarcinoma in situ of the cervix uteri and related lesions, III.
Advise women who already have CIN, adenocarcinoma in situ, VIN, VAIN, or benign anogenital disease that the vaccine is not therapeutic and will not prevent the natural progression of these lesions toward cancer.
Papanicolaou smear sensitivity for adenocarcinoma in situ of the cervix: a study of 34 cases.
Assessment of invasion in lung adenocarcinoma classification, including adenocarcinoma in situ and minimally invasive adenocarcinoma.
Adenocarcinoma in situ is almost always diffusely and strongly p16 positive (with rare exceptions), (44-56) with MIB1 and ProExC showing positivity in greater than 30% and 50% of tumor cells, respectively.
This lesion therefore also represents an adenocarcinoma in situ of the nonmucinous type.
Many tumors diagnosed as BAC according to the 1999 (2) and 20043 WHO classifications are now reclassified in the new classification into 5 different entities including (1) adenocarcinoma in situ (AIS) or solitary small noninvasive peripheral lung tumors, associated with a 100% 5-year survival if completely resected (5,8); (2) minimally invasive adenocarcinomas (MIAs), which are associated with nearly 100% 5-year survival if completely resected (8,25,26); (3) invasive adenocarcinomas with a lepidic component (27-31); (4) invasive mucinous adenocarcinoma (former mucinous BAC) (14,27-30); and (5) widespread advanced-stage adenocarcinomas with a lepidic component, which are associated with a very poor survival rate.
One of the most important changes in terminology is the designation of neoplasms previously classified as bronchioloalveolar carcinoma as adenocarcinoma in situ to emphasize that they tend not to spread to regional lymph nodes or to metastasize.
Tumors previously included in this term were separated into adenocarcinoma in situ versus invasive adenocarcinomas.