OC28: Effects of medical therapy on deep endometriosis: a sonographic study

Medical therapies that suppress ovarian function are effective and alternative methods in pain-related relief of deep infiltrating endometriosis (DIE). The aim of this study was to assess whether the sonographically detectable posterior pelvic deep endometriotic nodules changed in dimension and echostructure during different medical therapies. Twenty-two symptomatic premenopausal patients with a posterior pelvic DIE nodule underwent sonographic evaluation before and after at least 6 months of medical therapy. Treatments used to suppress ovarian function were GnRH agonists in six patients, add back therapy in nine patients, continuous contraceptive steroids in five and insertion of a levonorgestrel intrauterine system in two patients. The DIE nodules were measured and the echostructure and tissue infiltration at different sites and organs were accurately described. A comparison of dimensions and sonographic characteristics of the endometriotic nodules before and during medical therapy was performed. Nine patients had the largest nodule at the level of the uterosacral ligaments, six at the level of the pouch of Douglas, five at the level of the rectum sigmoid junction and two in the rectovaginal septum. Symptoms were completely relieved in 16 patients during therapy and significantly alleviated in the others. We observed a decrease in maximum diameter (28.1 ± 6.8 mm vs. 24.2 ± 7.9 mm) and in total volume (3.4 ± 2.4 mL vs. 2.3 ± 1.5 mL) of the endometriotic nodule during medical therapy; these changes were not statistically significant. None of the nodules disappeared during therapy; echostructure and infiltration of the surrounding tissue remained unchanged. Our sonographic findings confirmed that medical therapies do not cure DIE but only relieve pain and induce temporary quiescence of active lesions. This suggests the need for new prolonged medical treatments or surgical removal of DIE lesions.