myxoid degeneration of a leiomyoma
Myxoid degeneration of leiomyoma is one of the rarer types of degeneration that can occur in a uterine leiomyoma. This term is related but not identical to the term myxoid uterine leiomyoma.
Epidemiology
While this type of degeneration is generally considered rare, the highest prevalence for this type of degeneration has been reported as up to 50% of all degenerations of leiomyomas .
Pathology
Fibroids (i.e. uterine leiomyomas) that have undergone myxoid degeneration are filled with a gelatinous material and can be difficult to differentiate from cystic degeneration; however, they typically appear as more complex cystic masses. They appear hypocellular with a myxoid matrix .
Radiographic features
MRI
On pelvic MRI, the myxoid material usually demonstrates :
- T1: low signal intensity
- T2: usually high signal intensity with a peripheral low signal intensity
- T1 C+ (Gd): there is minimal or no enhancement
The above signal changes are of intralesional change on a background of low T2 signal of non-myxoid components.
Differential diagnosis
Certain malignant uterine tumors also show myxoid degeneration, e.g.leiomyosarcoma