Atypical Polypoid Adenomyoma (APAM) of the Uterine: Relationship with Endometrial Cancer

Abstract

Atypical polypoid adenomyoma (APAM) is a rare polypoid tumor that generally occurs in women of reproductive age who have abnormal genital bleeding. The tumor was reported as a new disease concept by Mazur in 1981. Pathologically, APAM consist of irregularly proliferated endometrial gland cells and interlacing bundles of smooth muscle cells within the stroma, and have a similar form to adenocarcinoma, adenofibroma, adenosarcoma, and carcinosarcoma. Therefore, differential diagnosis is required in many cases. APAM is pathologically classified as a benign lesion and clinically has a comparatively favorable outcome. However, treatment and follow-up observation should be performed carefully because recurrence and residual lesions occur in many patients after conservative treatment. Concomitant development of endometrial adenocarcinoma also occurs in many cases and it is difficult to differentiate this disease from APAM. Thus, diagnosis of APAM should be made carefully, particularly since the number of cases of endometrial adenocarcinoma has increased in recent years. Furthermore, APAM tends to develop during a woman’s reproductive years, and fertility sparing treatment should be considered. Here, we review the clinicopathological characteristics of APAM, including the difficulty of diagnosis as a benign or malignant uterine tumor, and we examine the relationship between APAM and endometrial cancer.