Prospective randomized study comparing the GnRH-agonist leuprorelin acetate and the gestagen lynestrenol in the treatment of severe endometriosis

Endometriosis is thought to be an ovarian-dependent benign disease that aff ects up to 12% of women during their reproductive life. For the past ten ye ars the gonadotropin-releasing hormone (GnRH)-agonists have been proved eff ective and safe drugs in the treatment of endometriosis. Nevertheless, gestagens such as lynestrenol still remain the most often use d hormonal drugs for the treatment of this disease. The primary objective of this study was to compare the efficacy of the GnRH -agonist leuprorelin acetate depot (LAD) (Enantone((R))-Gyn) 3.75 mg subcut aneously per month with that of the gestagen lynestrenol (LYN) (Orgametril( (R))) 5 mg orally twice per day in women with severe endometriosis, in term s of postoperative revised American Fertility Society (r-AFS) scores I-IV a t first-look laparoscopy (score after removal of endometriotic lesions or a dhesions) to the r-AFS score after six months' treatment. Secondary objecti ves were the improvement of clinical symptoms and the side-effect profile. Forty-eight women with postoperative r-AFS scores I-IV were evaluated in an open prospective randomized study between 1996 and 1998. All the participa nts underwent a first-look laparoscopy with resection of endometriotic lesi ons and six months' therapy with one of the above mentioned drugs, and a fu rther second-look laparoscopy. The six months' treatment with LAD or LYN led to a significant reduction of the r-AFS score points in both groups. The mean r-AFS score in points for the LAD group after the first-look laparoscopy was 21.8 and was 27.2 for th e LYN group. After the medical treatment a mean value of 11.5 points was ob served in the LAD group compared with a mean value of 25.5 in the LYN group . This difference was statistically significant (p = 0.000014, Wilcoxon tes t). The improvement in the symptoms of dysmenorrhea, chronic pelvic pain an d dyspareunia was also more pronounced in the LAD-treated group. LAD was mo re effective than LYN in the suppression of circulating serum 17 beta -estr adiol levels after 6 months of treatment (mean 27.7 +/- 9.3 pg/ml versus 42 .6 +/- 59.3 pg/ml). All the observed side-effects were deemed tolerable by the women who participated in this study. As the reduction of the r-AFS sco re in points was much more pronounced in the LAD group than in the LYN grou p, GnRH-agonists should therefore be used as first-choice drugs in the trea tment of endometriosis. Dire to the limited treatment of 6 months' duration of GnRH-agonists, gestagens might be used as second-line drugs for long-te rm and continuous treatment in the management of endometriosis to maintain the primary beneficial effect of GnRH-agonist treatment in patients who hav e completed their families.