The Great Masquerader: Accessory Cavitating Uterine Mass (ACUM). Evaluation, diagnosis, and surgical management

OBJECTIVE: Accessory cavitating uterine masses (ACUM) are rare, cystic uterine anomalies associated with an otherwise normal uterus and reproductive tract. They are diagnosed via a presence of a noncommunicating accessory cavity lined by endometrium and surrounded by uterine smooth muscle [1]. MRI and 3D ultrasound are preferred imaging modalities for evaluation, as misdiagnosis is common [2]. Medical therapy is aimed at menstrual suppression and pain management, however these masses are likely to fail medical management. Surgical management leads to virtual complete remission of symptoms [3]. As these are uncommon, this surgical video aims to inform practitioners on diagnosis and key elements of surgical management of an accessory cavitating uterine mass (ACUM). DESIGN: Intraoperative videography. All patients [2] diagnosed with ACUM at an academic medical center from December 2023 to May 2024 were included. SUBJECTS: Two reproductive-aged females with dysmenorrhea found to have ACUM after imaging (3D ultrasound and MRI pelvis). INTERVENTION: Laparoscopic and robotic-assisted resection of ACUM along with diagnostic hysteroscopy, chromopertubation, and excision of endometriosis. MAIN OUTCOME MEASURES AND RESULTS: Restoration of normal uterine anatomy and improved patient symptoms. CONCLUSION: ACUM is a rare and largely misdiagnosed Mullerian anomaly. Early recognition and surgical intervention improves patients' quality of life. Key intraoperative and postoperative considerations must be taken with surgical revision of ACUM. More data is needed on the gynecologic and obstetric outcomes associated with surgical resection of ACUM.