Uterine angioleiomyoma: a rare variant of uterine leiomyoma.

Uterine angioleiomyoma is an extremely rare and unique variant of leiomyoma. It usually occurs in middle-aged women, who commonly present with menorrhagia, abdominal pain, or abdominal mass. The lesions are either single or multiple and manifest as submucosal, intramural, or subserosal whorled nodules. Microscopy of the individual nodule shows interlacing fascicles of spindle cells swirling around thick-walled blood vessels. Angioleiomyoma usually lacks mitotic figures, pleomorphism, or necrosis, although cases with marked nuclear atypia and multinucleated giant cells have been reported. The tumor cells are immunoreactive for smooth muscle actin, desmin, h-caldesmon, and progesterone receptor, with a low Ki-67 labeling index. Because these lesions are vascular, they may undergo spontaneous rupture and pose a life-threatening emergency, especially in pregnancy. There are no specific imaging findings; therefore, a preoperative diagnosis is extremely difficult. It is important to recognize this entity and differentiate it from a malignancy, particularly when angioleiomyoma shows significant cytologic atypia or raised cancer antigen 125 levels by thorough sampling. When required, a proper immunohistochemical panel should be used to arrive at a correct diagnosis. In this review, we discuss the current knowledge on uterine angioleiomyoma and its clinical relevance.