Diagnosis and Management of an Adenomatoid Uterine Tumor: Ultrasound, Magnetic Resonance Imaging, Surgical Appearance, and Pathology Correlation

Adenomatoid uterine tumors are rare, and their appearance on medical imaging modalities is not well established. We present a case of an adenomatoid uterine tumor reviewing a unique sonographic presentation, magnetic resonance imaging (MRI), gross surgical appearance of the tumor, and microscopic pathology images. A 29-year-old gravida 0 Caucasian woman presented with dysmenorrhea, menorrhagia, and desire to conceive. Transvaginal ultrasound revealed a 2.7 cm round, well-circumscribed posterior intramural uterine mass. The mass was hyperechoic centrally with a thin hypoechoic rim. Color Doppler imaging revealed a prominent vascular rim around the periphery of the mass as well as central vascularity not typical for a leiomyoma. MRI, with and without intravenous gadolinium, was obtained showing a 2.7 cm posterior fundal mildly enhancing uterine mass suggestive of leiomyoma. The mass had a heterogeneous signal pattern on T2-weighted images, and no fat component was noted within the mass. Repeat transvaginal ultrasound showed interval growth of the mass to 3.5 cm with a lipomatous appearance. Adenomatoid uterine tumors are rare and may be mistaken for uterine leiomyomata. Unique features include sonographic appearance of central hyperechogenicity with a hypoechoic rim and prominent peripheral and central vascularity in conjunction with MRI revealing a heterogeneous signal pattern on T2-weighted images without fat component. Gross surgical appearance reveals a nondiscrete capsule and secretion of mucoid material when the mass is exposed. We present a case of adenomatoid tumor providing sonographic, MRI, surgical, and pathological correlation. The patient subsequently conceived spontaneously and delivered at term by cesarean section. The patient underwent a preoperative evaluation with complete blood count, comprehensive metabolic panel, blood type with antibody screen, and pregnancy test. She underwent laparoscopic excision with robotic assistance for removal of the tumor. Grossly, the uterine mass had a very soft consistency atypical for a uterine leiomyoma making dissection more challenging. During dissection the mass diffusely secreted a mucoid material although the capsule was not disrupted. The lesion was excised intact and was removed from the peritoneal cavity in an endocatch bag without internal morcellation. Microscopic examination revealed an adenomatoid tumor.