Isolated morular squamous metaplasia in endometrial biopsies and curettings: is there a role for repeated sampling?

Isolated squamous morular metaplasia without associated glandular neoplasia is a rare finding, reported only in 0.17% of endometrial samples. The risk of subsequent endometrioid neoplasia appears to be low (5.4%), although the possibility of undersampled atypical hyperplasia/endometrioid carcinoma cannot be completely ruled out without additional sampling. Persistent squamous morular metaplasia is relatively uncommon (4.5%) and may not lead to the subsequent diagnosis of endometrial cancer, questioning the utility of numerous repeat samplings in patients without progression after one repeat sample.