New cases of accessory and cavitated uterine masses (ACUM): a significant cause of severe dysmenorrhea and recurrent pelvic pain in young women

To raise awareness about the accessory and cavitated uterine masses (ACUM) with functional endometrium as a different entity from adult adenomyosis and to highlight the importance of a correct diagnosis, we studied four new cases of ACUM and 15 cases reported as juvenile cystic adenomyoma (JCA) by reviewing the literature from the last year. This entity is problematic because of a broad differential diagnosis, including rudimentary and cavitated uterine horns; and is generally underdiagnosed, being more frequent than previously thought.