Immunohistochemical detection of insulin-like growth factor type I receptor and uterine volume changes in gonadotropin-releasing hormone analog-treated uterine leiomyomas.

Objective: This study was undertaken to assess the relationship between insulin-like growth factor (IGF) type I receptor (IGF-I-R) expression in uterine leiomyomas after gonadotropin-releasing hormone (GnRH) analog administration and modifications in uterine size.
Study Design: Forty-six women with menorrhagia for uterine leiomyomatosis were treated monthly with leuprolide acetate depot 3.75 mg before undergoing surgery. The uterine volume before and after therapy was assessed by transabdominal ultrasonography. Immunohistochemical detection of IGF-I-R was performed on leiomyoma tissue samples. The relationship between IGF-I-R levels and uterine volume changes was analyzed.
Results: Uterine volume decreased after therapy. Patients with a lower immunohistochemical expression of IGF-I-R showed a larger decrease in uterine size.
Conclusion: The shrinkage in uterine volume induced by GnRH analogs seems to be related to the observed reduction in IGF-I-R levels. So, the IGF-I/IGF-I-R system might be involved in leiomyoma growth, and the pharmacologic action of GnRH analogs on uterine leiomyomas might also be related to the effects on IGF-I-R expression.