Changes in the size of rectovaginal endometriotic nodules infiltrating the rectum during hormonal therapies

Purpose: To evaluate the changes in the volume of rectovaginal endometriotic nodules infiltrating the rectum during 12-month treatment with hormonal therapies. Materials and methods: This prospective, non-randomized, self-controlled clinical trial included patients with rectovaginal endometriotic nodules infiltrating at least the muscularis propria of the rectum, who received one of the following therapies: norethisterone acetate, triptorelin and tibolone, norethisterone acetate and letrozole, desogestrel, sequential oral contraceptive pill. The volume of the nodules was determined by virtual organ computer-aided analysis (VOCAL, GE Healthcare, USA) at baseline and after 6 and 12 months of treatment. Results: Eighty-three women (90.2 %) completed the 12-month treatment. When compared with baseline values, the volume of the nodules decreased at 6-month (p <0.001) and 12-month treatment (p <0.001). After 12-month treatment, the volume of the nodules decreased in all study groups. The volume of the nodules decreased during therapy in 68 women (73.9 %) and increased in 11 women (12.0 %). Conclusion: 12-month administration of hormonal therapies reduces the volume of rectovaginal endometriotic nodules infiltrating the rectum in the majority of cases.