A Large Pure Uterine Lipoma: Its Diagnosis by Pelvic MRI and Histopathology

Abstract

The patient is a 74-year-old female previously diagnosed with an ovarian tumor at age 55. No changes were noted for one year; however, she was lost to follow-up. Eighteen years later, she presented to a local clinic complaining of diffuse abdominal and flank pain. Abdominal and pelvic ultrasound, CT, and gynecological examination showed a fatty pelvic tumor of approximately 12 cm in diameter. A left ovarian teratoma was suspected, and per the patient's request, she was transferred to Kobe Adventist Hospital for further evaluation and treatment. Pelvic MRI revealed no ovarian enlargement; however, a mass in the uterine body was appreciated with a high signal on T1 and T2 images and signal dropout in the fat suppression images, a finding most consistent with a uterine lipoma. A total hysterectomy and bilateral salpingo-oophorectomy was performed, and histopathological examination confirmed the preliminary diagnosis. No complications were observed during the postoperative period. A pure uterine lipoma is an extremely rare tumor with only a few cases reported worldwide. It is a benign tumor; however, it can sometimes be misdiagnosed as a malignant neoplasm. Pelvic MRI appears to be a useful tool in order to make the correct diagnosis preoperatively.

Figure 1

Sagittal (a, b) and axial (c–e) MRI images of the uterine lipoma showing high signal on T1 (a, c) and T2 (b, d) sequences and low signal on fat suppression sequence (e).

Figure 2

Gross appearance of the uterus showing a well-circumscribed yellow tumor.

Figure 3

Hematoxylin & eosin staining of the uterine lipoma at ×10 (a) and ×40 (b) magnifications showing mature adipocyte lobules separated by fibrous septae.