OC20.08: Is endometriosis a progressive disease? Ultrasonographic long‐term study

The primary objective of this study was to assess the changes in the ultrasonographic characteristic of endometriosis in patients undergoing long-term follow-up. The secondary outcome of the study was to assess the long-term impact of hormonal therapies on the ultrasonographic characteristics of endometriosis. This study was based on the retrospective analysis of a prospectively collected database. The study included only patients with a minimum follow-up of 5 years and who did not undergo surgery for endometriosis before inclusion in the study. The follow-up ended in patients who underwent surgery, conceived, became spontaneously menopausal, or were lost at follow-up. Patients underwent transvaginal ultrasonography at least once per year and the characteristics of each endometriotic nodule were recorded using dedicated software. Presence, largest diameter and volume (assessed by virtual organ computer-aided analysis) of the lesions were evaluated. 416 patients were included in the study. The length of follow-up ranged from 5 to 15 years; the median follow-up time was 8.2 years. There was no significant increase in largest diameter and volume of deep endometriotic nodules during the study period. Similar findings were observed when the analysis was restricted to 74 patients (median follow-up 7.1 years) who did not receive hormonal therapy. An increase in the size of at least one deep endometriotic nodule was observed in 49 patients (11.8%; 95% C.I. 8.8%-15.3%). The hormonal therapy decreased the largest diameter and the volume of ovarian endometriomas; in addition, it prevented the development of newly diagnosed ovarian endometriomas. The size of endometriomas significantly increased in patients who did not receive hormonal therapy. In most of the patients, there is no ultrasonographic evidence of progression of deep endometriotic nodules during long-term follow-up. Ultrasonographic follow-up shows an increase in the size of endometriomas and the development of new endometriotic cysts in patients who do not receive hormonal therapies.