Role of IGF1 in primary ovarian cancer – a study of the OVCAD European Consortium

Introduction: IGF1 (insulin growth factor 1) is a hormone crucially involved in the physiology of cellular proliferation. Moreover, deregulation of IGF1 was shown to be relevant in the carcinogenesis of various tumor entities including breast cancer. However, the impact in the pathophysiology of ovarian cancer is unclear. Therefore we investigate the predictive and prognostic role of IGF1 circulatory levels in a collective of 275 primary epithelial ovarian cancer (EOC) patients.

Methods: In the FP6 European Multicentric Project "OVCAD", 275 consecutive patients with primary EOC were enrolled. Patients were eligible if radical cytoreductive surgery was performed and platinum-based chemotherapy was applied. Samples of plasma and ascites were collected before or during surgery.

Results: Increased plasma IGF 1 levels were more frequently found in low-grade serous and non-serous carcinoma (p = 0,0047) than in high-grade ovarian cancers. No significant correlations with other clinicopathological factors such as FIGO stage, residual tumor mass, age at initial diagnosis, histology or CA 125 have been found. No association between IGF1 expression and BMI was observed.

Conclusion: IGF1 is significantly over-expressed in patients with G1 serous ovarian cancers. No association between circulatory IGF1 levels and overall survival has been seen in the univariate analysis. Further studies are warranted to elucidate the role of IGF1 expression in the pathogenesis of G1 tumors. The low grade EOC are chemotherapy resistant, therefore the identification of new biomolecular targets is a clinical unmet need. IGF-1 would be an interesting candidate in future targeted therapy concepts.