retroperitoneal Mullerian cyst

Urogenital cysts arise from vestiges of the embryonic urogenital apparatus and can be classified on their embryonic lines into:
 pronephric
 mesonephric
 metanephric
 müllerian (paramesonephric).

Müllerian cyst of the retroperitoneum is an extremely rare disease that is thought to be a subtype of urogenital cyst. It is a benign condition that can be cured with surgical resection.

Müllerian cyst of the retroperitoneum occurs in women from 19 to 47 years of age.

With respect to pathogenesis, the retroperitoneal tissue may have an aberrant müllerian duct remnant, which might have a capacity for growth in the case of abnormal hormonal stimuli.

Lee et al. asserted that hormonal stimuli influenced the growth of müllerian cyst because most patients received several hormone shots for menstrual irregularities.

At CT, müllerian cyst manifests as a unilocular or multilocular thin-walled cyst containing clear fluid.

The differential diagnosis includes :
 cystic mesothelioma
 cystic lymphangioma.

Clinical history may be useful for differentiating müllerian cyst from other retroperitoneal cystic masses because the former usually occurs in obese patients with menstrual irregularities.

At microscopic analysis, the cyst is lined with cuboidal to columnar epithelial cells with cilia, and the cyst wall consists of thicker smooth muscle.

Synopsis

 cyst lined by ciliated, cuboidal to low columnar epithelial cells resembling fallopian tube epithelium.