A case of a large uterine lipoleiomyoma

Clinical History

A 77-year-old post-menopausal woman presented to our hospital in the year 2012 with per-vaginal haemorrhage. Her abdominal examination revealed a suspicious pelvic mass. However, due to pain, vaginal examination was not possible.

Imaging Findings

She initially had a transabdominal and transvaginal ultrasound which showed:
Fig. 1. Transvaginal ultrasound showing hyperechoic lesion with a partially hypoechoic rim.

Following that, she underwent a pelvic MRI.
Fig. 2. Axial T1-weighted MR image shows well-circumscribed hyperintense mass with hypointense bands in the myometrium of the uterus. Axial T2-weighted MR image shows hyperintense mass with hypointense bands. Axial T1-weighted fat-suppressed MR image shows signal suppression of hyperintense area on T1-weighted image.

Her recent CT abdomen and pelvis in 2017 showed an increase in the size of the lesion.
Fig. 3. Sagittal CT shows well-defined fat-containing mass with areas of soft tissue density.

Discussion

Lipoleiomyomas are uncommon neoplasms of the uterus with a reported incidence of 0.03-0.20%. [1] They are considered to be a variant of uterine leiomyoma. [2]
They are thought to be the result of fatty metaplasia of the smooth muscle cells and generally consist of smooth muscle and fat cells which are separated by fibrous tissue. [3]
Patients are asymptomatic. However, they can sometimes present with palpable abdominal or pelvic mass, pain and hypermenorrhoea. [3]
Different imaging modalities are being used to investigate these tumours and to exclude other pathologies. Ultrasound shows a hyperechoic lesion with a partially hypoechoic rim which represents a layer of myometrium surrounding the fatty central component. Vascularity may or may not be seen (Fig 1). A well-defined fat-containing mass is found on CT with areas of soft tissue density. MRI is the gold standard modality to investigate these tumours (Fig 3). They are hyperintense on T1 and T2-weighted sequences. Fat suppression sequences can be useful to confirm the diagnosis which demonstrates hypointensity on both T1 and T2 sequences [3] (Fig 2).
Lipoleiomyomas are benign tumours and do not require treatment unless they become symptomatic, in which case they may be treated by uterine artery embolisation or surgical resection. [1]

Differential Diagnosis List

Final Diagnosis

Based on the imaging findings the diagnosis is lipoleiomyoma.

URL:	https://eurorad.org/case/15550
DOI:	10.1594/EURORAD/CASE.15550
ISSN:	1563-4086