[Expression of nerve growth factor produced by ectopic endometrium from patients with adenomyosis and its relationship with pain scales and innervation].

OBJECTIVE: To investigate the expression of nerve growth factor (NGF) in the ectopic endometrium in adenomyosis patients, and explore the relationship between NGF expression and innervation or pain scales. METHODS: From Mar. 2009 to Oct. 2009, 45 adenomyosis patients undergoing hysterectomy in Obstetrics and Gynecology Hospital of Fudan University were enrolled in this study, which were classified into 33 cases in pain group and 12 cases in non-pain group based on symptom. The degree of dysmenoreal, chronic pelvic pain and dyspareunia was evaluated by visual analogue scale, including no pain, mild to moderate pain and severe pain group. In the mean time, 26 patients with leiomyoma or cervical intraepithelial neoplasia III (CIN III) undergoing hysterectomy were defined as control group. Ectopic endometrium from experimental group and eutopic endometrium from control group were collected in the surgery. The expression of NGF was examined by immunohistochemistry. The density of protein gene product (PGP) 9.5 positive nerve fibers was detected by immuno-fluorescence. RESULTS: The NGF level and the density of PGP 9.5 positive nerve fibers in adenomyosis pain group (0.25 ± 0.08, 16 ± 8 )were higher than adenomyosis painless (0.19 ± 0.05, P = 0.007;11 ± 5, P = 0.018) and control group (0.18 ± 0.05, P = 0.000; 9 ± 4, P = 0.000) . The NGF level and the density of PGP9.5 positive nerve fibers in severe dysmenorrheal group (0.29 ± 0.07, 19 ± 10) were higher than mild to moderate dysmenorrheal (0.22 ± 0.07, P = 0.018;13 ± 4, P = 0.035) and painless group (0.18 ± 0.05, P = 0.000;11 ± 5, P = 0.006) of adenomyosis patients. There was no difference of NGF level and the density of PGP 9.5 positive nerve fibers in chronic pelvic pain group and no chronic pelvic pain group of adenomyosis patients, so was dyspareunia group and no dyspareunia group. CONCLUSION: The increased NGF level of adenomyosis nodules and improving innervation might be involved in the mechanism of adenomyosis related pain.