Biological characteristics related to treatment effects of the levonorgestrel-releasing intrauterine system on adenomyosis-associated dysmenorrhoea

Research question

Are there correlations between the biological expression of steroid receptors and the extent of fibrosis in adenomyotic lesions, and the treatment effectiveness of the levonorgestrel-releasing intrauterine system (LNG-IUS) on alleviation of adenomyosis-associated dysmenorrhoea.

Design

In this retrospective cohort study, 125 women with adenomyosis who underwent hysterectomy were screened. Tissue samples were collected from 41 patients who had undergone LNG-IUS treatment prior to surgery, and these patients were further categorized into the treatment effective group (n = 18) and the treatment failure group (n = 23) according to their self-reported relief from dysmenorrhoea after 6 months of treatment. Oestrogen receptor-α (ER-α) and progesterone receptor expression, and the extent of fibrosis in the adenomyotic lesions were measured using immunohistochemistry and Masson's trichrome staining, respectively.

Results

Patients in the treatment failure group demonstrated lower expression of ER-α and progesterone receptors, and more pronounced fibrosis in the stroma of adenomyotic lesions compared with patients in the treatment effective group. In the glandular epithelium of lesions, ER-α expression was reduced significantly in the treatment failure group, whereas no notable difference in the expression of progesterone receptors was observed. Notably, the staining intensity of ER-α in the stroma of lesions was found to have the strongest positive correlation with the degree of symptom alleviation for dysmenorrhoea (r = 0.703, P < 0.001), with an area under the curve of 0.894 for prediction.

Conclusions

The reduced expression of steroid receptors in adenomyotic lesions, especially ER-α in the stroma, was associated with increased likelihood of treatment failure of LNG-IUS for alleviation of dysmenorrhoea.