OP14.02: Changes in the volume of rectosigmoid endometriotic nodules during 24‐month treatment with dienogest: prospective cohort study

The primary objective of this study was to evaluate the changes in the volume of rectosigmoid endometriotic nodules during treatment with dienogest (DNG). The secondary aim of the study was to assess the changes in pain and intestinal symptoms. This 24-months open-label prospective cohort study included symptomatic women of reproductive age with rectosigmoid endometriosis. Subjects of the study did not suffer subocclusive symptoms and had estimated bowel stenosis < 70%. The diagnosis of bowel endometriosis was based on transvaginal ultrasonography. Eligible patients received DNG (2 mg/day) for 24 months. The volume of the rectosigmoid nodules was estimated by using the virtual organ computer-aided analysis (VOCAL) at baseline and every six months during treatment. 32 patients were enrolled in this study and 87.5% (28/32) of them completed the 24-months treatment. The mean (±SD) age of the study population was 33.5 (±3.2 years). 56.2% (18/32) of the patients had previously received other hormonal treatments for endometriosis. There was a significant reduction in the volume of the rectosigmoid endometriotic nodules between baseline and 12-month treatment (p < 0.001) and between baseline and the end of treatment (4.2 ± 0.7 cm3and 3.3 ± 0.8 cm3, p < 0.001). There was no significant difference in the volume of the nodule between 12-month and 24-month treatment (p = 0.527). A significant improvement in the intensity of dysmenorrhea, non-menstrual pelvic pain, deep dyspareunia and dyschezia was reported during the therapy. The severity of diarrhea, intestinal cramping and passage of mucus significantly improved at 6 and 24 months versus baseline. DNG was well tolerated with no serious adverse event; the most common adverse effect was headache (6.3%, 2/32). A 2-year therapy with DNG causes a significant decrease in the size of the rectosigmoid endometriotic nodules. Furthermore, it improves symptoms caused by rectosigmoid endometriosis with good safety-profile. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.