Insulin-like growth factor I and risk of epithelial invasive ovarian cancer by tumour characteristics: results from the EPIC cohort.
Ose J., Fortner RT., Schock H., Peeters PH., Onland-Moret NC., Bueno-de-Mesquita HB., Weiderpass E., Gram IT., Overvad K., Tjonneland A., Dossus L., Fournier A., Baglietto L., Trichopoulou A., Benetou V., Trichopoulos D., Boeing H., Masala G., Krogh V., Matiello A., Tumino R., Popovic M., Obón-Santacana M., Larrañaga N., Ardanaz E., Sánchez M-J., Menéndez V., Chirlaque M-D., Travis RC., Khaw K-T., Brändstedt J., Idahl A., Lundin E., Rinaldi S., Kuhn E., Romieu I., Gunter MJ., Merritt MA., Riboli E., Kaaks R.
BACKGROUND: Prospective studies on insulin-like growth factor I (IGF-I) and epithelial ovarian cancer (EOC) risk are inconclusive. Data suggest risk associations vary by tumour characteristics. METHODS: We conducted a nested case-control study in the European Prospective Investigation into Cancer and Nutrition (EPIC) to evaluate IGF-I concentrations and EOC risk by tumour characteristics (n=565 cases). Multivariable conditional logistic regression models were used to estimate associations. RESULTS: We observed no association between IGF-I and EOC overall or by tumour characteristics. CONCLUSIONS: In the largest prospective study to date was no association between IGF-I and EOC risk. Pre-diagnostic serum IGF-I concentrations may not influence EOC risk.