Broad ligament leiomyoma

Broad ligament leiomyomas are extra-uterine leiomyomas that occur in relation to the broad ligament. 

Terminology

Broad ligament leiomyomas are also referred as a type of parasitic leiomyomas ⁵.

Clinical presentation

While in most cases broad ligament leiomyomas are asymptomatic, patients may present pelvic pain or a palpable pelvic mass. The pain, when long-standing, may be as a result of pressure effects on adjacent organs, such as the bladder or ureter; or, when acute, due to a complicating torsion.

Pathology

It is a type of extra-uterine leiomyoma that arises from the smooth muscle elements of the broad ligament ⁵. 

Radiographic features

A leiomyoma occurring in this location poses greater diagnostic difficulty than when it occurs in the uterus. In uncomplicated cases (e.g no degeneration) it is seen as a solid adnexal mass which is separate from both the uterine body as well as the ovary.

Ultrasound

Usually seen as a hypoechoic, solid, well-circumscribed adnexal mass, although that can be heterogeneous when large. There is generally no interface between the tumour and uterus and no straight relation to the ipsilateral ovary.

MRI

Signal characteristics in uncomplicated cases are similar to those exhibited by uterine leiomyomas:

• T1: iso to low signal
• T2: typically low signal
• T1 C+: most enhance similarly to the myometrium while larger leiomyomas tend to enhance less and heterogeneously

Treatment and prognosis

Torsion of the leiomyoma can occur if pedunculated.

Differential diagnosis

General considerations include:

• other unusual leiomyomas
  • parasitic leiomyoma involving the broad ligament
  • pedunculated subserosal leiomyoma projecting towards the broad ligament
• solid ovarian neoplasms: particularly those with dominant fibrous components
  • ovarian fibroma or fibrothecoma: tend to be inseparable from the ovary
  • Brenner tumour: tend to be inseparable from the ovary
• other ligamentous mesenchymal tumours
  • neurofibroma in the pelvis