Atypical polypoid adenomyoma (APA) is a rare benign

tumour A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

of the

uterus The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The ...

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Pathology

APAs are characterized by

gland In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream ( endocrine gland) or into cavities inside the body or its outer surface ( exocrine gland). Structure ...

s with abnormal shapes that: (1) often have

squamous metaplasia Squamous metaplasia is a benign non-cancerous change (metaplasia) of surfacing lining cells ( epithelium) to a squamous morphology. Location Common sites for squamous metaplasia include the bladder and cervix. Smokers often exhibit squamous m ...

, and (2) are surrounded by benign

smooth muscle Smooth muscle is an involuntary non- striated muscle, so-called because it has no sarcomeres and therefore no striations (''bands'' or ''stripes''). It is divided into two subgroups, single-unit and multiunit smooth muscle. Within single-unit ...

Nuclear atypia Nuclear atypia refers to abnormal appearance of cell nuclei. It is a term used in cytopathology and histopathology. Atypical nuclei are often pleomorphic. Nuclear atypia can be seen in reactive changes, pre-neoplastic changes and malignancy. S ...

, if present, is mild. The microscopic differential diagnosis includes

endometrial carcinoma Endometrial cancer is a cancer that arises from the endometrium (the lining of the uterus or womb). It is the result of the abnormal growth of cells that have the ability to invade or spread to other parts of the body. The first sign is most o ...

and endocervical adenocarcinoma. Image: Atypical polypoid adenomyoma - intermed mag.jpg , Intermed. mag. Image: Atypical polypoid adenomyoma - very high mag.jpg , Very high mag.

References

Benign neoplasms Noninflammatory disorders of female genital tract {{oncology-stub

Pathology

See also

References