IGF-1 AND IGFBP-3 IN COLORECTAL CANCER, AN OBSERVATIONAL CASE-CONTROL STUDY

SÜLEYMAN BADEMLER¹, ALIŞAN ZIRTILOĞLU², MURAT SARI³, CEREN TILGEN YASASEVER⁴, SENEM KARABULUT³

¹Department of Surgery, Institute of Oncology, Istanbul University, Istanbul, Turkey - ²Department of Medical Oncology, Bakirkoy Dr. Sadi Konuk Education and Research Hospital, Istanbul, Turkey - ³Department of Medical Oncology, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey - ⁴Department of Basic Oncology, Institute of Oncology, Istanbul University, Istanbul, Turkey

Introduction: Plasma levels of Insulin-Like Growth Factor-1 (IGF-1) and Insulin-Like Growth Factor Binding Protein-3 (IGFBP-3) have been studied in terms of colorectal cancer formation and prognosis, until now. However, these studies have con- flicting results. We aimed to contribute to the debate about whether serum IGF-1 and IGFBP-3 levels act on the colorectal cancer diagnosis and prognosis.

Materials and methods: A total of 117 colorectal cancer patients with histologically proven diagnosis treated at the Istanbul University, Institute of Oncology were enrolled into the study. For comparison of serum IGF-1 and IGFBP-3 levels, 53 age- and sex-matched healthy controls were included in the analysis.

Results: Serum IGFBP-3 levels were higher in control group than patients (p=0.008), while there was no significant differ- ence in levels of serum IGF-1 and IGF-1/IGFBP-3 between two groups. Between stage M0 and M1 patients, there was a signifi- cant difference only in levels of serum IGFBP-3 (p=0.024). Among patients between dead and alive, there was a significant differ- ence only in levels of serum IGFBP-3 (p=0.001). In the univariate survival analysis, only serum levels of IGFBP-3 had a statisti- cally significant impact on survival. Patients with higher IGFBP-3 levels (median overall survival(OS):48 months) had better OS than the patients with the lower IGFBP-3 (median OS:24 months) levels (p<0.001), which means higher levels of IGFBP-3 may have a positive prognostic effect on survival.

Conclusion: Lower serum concentrations of IGFBP 3 may be a diagnostic and also a prognostic marker in colorectal can- cer patients. Larger scale studies are needed to determine the precise role of serum IGF-1 and IGFBP-3 levels in colorectal can- cer disease.