Abstract

Morular metaplasia is recognized as formation of scattered cell ball-like aggregates mostly close to endometrial glands, and immunostained by monoclonal antibodies to CD10 (endometrial stromal differentiation), CDX2 (a biomolecule related to intestinal glandular cells), and internalization of β-catenin from cell membrane. It is a benign change and sometimes related to atypical polypoid adenomyoma of uterine cavity. Squamous metaplasia, or so-called squamous morular metaplasia, may be caused by chronic irritative status, is immunostained by monoclonal antibodies to high-molecular-weight cytokeratin and p63. Although squamous metaplasia looks like the morular metaplasia, it is a rare change of benign endometrium. In the contrast, squamous differentiation of endometrioid carcinoma is not a rare situation. Herein we present a case of 42-year-old woman of irregular menstruation and vaginal bleeding with the endometrium undergoing morular metaplasia and focally florid morular metaplasia, which is proved by immunohistochemical studies. Taken together, the term of ‘squamous morular metaplasia’ should be avoided on account of ambiguous meaning.

Keywords: Endometrial Metaplasia; Morular Metaplasia; Squamous Differentiation; Squamous Metaplasia

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