Bladder endometriosis: getting closer and closer to the unifying metastatic hypothesis

It has been hypothesized that bladder endometriotic nodules are an independent form of endometriosis that should be considered a distinct clinical entity. If this is true, the frequency of nonvesical endometriotic lesions in affected patients should be similar to the prevalence of the disease in the general population (about 10%). The aim of the study was to evaluate the presence of other forms of endometriosis in patients with bladder endometriotic nodules.

Case series.

Two gynecologic surgical units.

Fifty-eight women with large bladder endometriotic nodules.

To evaluate the concomitant presence of other forms of endometriosis.

Presence of superficial peritoneal implants, ovarian endometriomas, adhesions, and extravesical deep peritoneal endometriosis.

The presence of superficial peritoneal implants, ovarian endometriomas, adhesions, and extravesical deep peritoneal endometriosis was observed in 58.6% (95% confidence interval [CI]: 45.2-71.2), 44.8% (95% CI: 32.2-58.2), 81.0% (95% CI: 68.4-89.6), and 27.6% (95% CI: 16.7-40.8) of cases, respectively. The presence of at least one of them was documented in 87.9% of cases (95% CI: 76.7-94.3).

Endometriotic nodules of the bladder are frequently associated with other forms of pelvic endometriosis. This result does not support the vision that bladder endometriotic nodules should be considered an independent form of the disease.