Atypical polypoid adenomyoma, abbreviated APA, is a rare uncommon benign tumour of the uterus.
Atypical polypoid adenomyoma Wikipedia
APAs are characterized by glands with abnormal shapes that: (1) often have squamous metaplasia, and (2) are surrounded by benign smooth muscle. Nuclear atypia, if present, is mild.
The microscopic differential diagnosis includes endometrial carcinoma and endocervical adenocarcinoma.