[Clinical study of dienogest in the treatment of refractory endometriosis-associated pain]

Objective: To evaluate the efficacy and safety of dienogest (DNG) in the treatment of refractory endometriosis-associated pain (REAP). Methods: In this study, REAP was defined according to the following criteria: (1) the pain duration was ≥12 months and visual analogue scale (VAS)≥60 mm; (2) the previous treatments with over two medicines like oral contraceptives and levonorgestrel-releasing intrauterine system failed to achieve satisfactory relief of pain, with VAS reduction less than 50%; with gonadotropin-releasing hormone agonist or mifepristone, the pain could be controlled temporarily, but it recurred after discontinuation of medicines; (3) the pain could not be relieved by surgery or even repeated surgeries. In the present study, 48 patients with REAP were treated with DNG 2 mg/day orally and the clinical outcomes were retrospectively analyzed. The VAS scores, levels of CA125, estradiol, FSH, LH and changes in the size of endometriotic lesions before and after treatment were compared respectively. The side effects were also analyzed. Results: The average duration of DNG treatment was (20.1±12.8) months. After 3 months of medication, the VAS score was significantly reduced from (77.9±15.8) mm to (20.8±10.7) mm (P<0.01), and CA125 level was significantly reduced from (95±139) kU/L to (38±45) kU/L (P<0.05). The effects were maintained with continuation of DNG treatment. Endometriotic lesions tended to shrink, after 12 months of DNG treatment, the size of ovarian endometriomas was reduced significantly from (3.1±1.0) cm to (1.9±1.2) cm (P<0.05). The mean level of estradiol was maintained at 124.82-221.04 pmol/L and levels of FSH and LH did not change significantly during the treatment. The major side effect was irregular bleeding (75%, 36/48). Conclusions: DNG could effectively relieve REAP and is a well-tolerated therapy. It may supply an alternative option for patients with REAP.