IGF-I serum levels have been demonstrated as being associated with prostate cancer (PCa) and can serve as a predictive factor for the risk of PCa development. However, the role of IGF-II in PCa and its importance as a predictive marker is still unclear. Our aim was to determine PSA and IGF-II serum levels in patients with PCa and benign prostatic hyperplasia (BPH) and to analyse the value of IGF-II as an additional predictive factor in the diagnostics of PCa.
112 patients who underwent surgery for BPH or PCa (no hormonal treatment, no further malignancies) were included in this study ((I) 38 PCa, PSA ≤ 15 ng/ml; (II) 34 PCa, PSA > 15 ng/ml; (III) 40 BPH). Preoperative serum levels of total PSA and total IGF-II were determined by ELFA and ELISA, respectively.
PSA levels were (I) 5.7 ± 1.9 ng/ml; (II) 25.0 ± 11.5 ng/ml and (III) 4.0 ± 2.8 ng/ml. (II) was statistically associated with a high grading (2b/3; p = 0.0182), a high Gleason sum score (7–10; p = 0.0049) and a non-organ confined tumor (T3/4; p = 0.0009) compared to (I), all Chi2 test. IGF-II levels were significantly higher in PCa (I + II) compared to BPH (833.8 ± 238.9 ng/ml vs. 633.3 ± 141.4 ng/ml, p < 0.0001, t-test). Both PSA and IGF-II were associated with tumor staging (p = 0.0097, p = 0.0308; t-test). No significant correlation was observed between PSA and IGF-II levels. Logistic regression analysis revealed that the combination of PSA and IGF-II improves the prediction of tumor staging in PCa (p = 0.0175 and p = 0.0459, Wald test). Additionally, the combination of PSA and IGF-II can significantly increase discrimination between BPH and PCa; each p < 0.0001, Wald test.
This study provides evidence that IGF-II serum levels may serve as an additional parameter for (a) improved determination of tumor staging and (b) better discrimination between BPH and PCa.
Keywords: Biological markers, Insulin-like Growth factor II, Prostate-specific antigen, Prostatic neoplasms, Prostatic hyperplasia.
a Department of Urology, University Hospital Mannheim, Heidelberg University, Germany
b Department of Medical Biometrics and Statistics, University Hospital Mannheim, Heidelberg University, Germany
c Research Group “Hormones and Signal Transduction”, Deutsches Krebsforschungszentrum, Heidelberg, Germany
d Department of Pathology, University Hospital Mannheim, Heidelberg University, Germany
Corresponding author. Department of Urology, University Hospital Mannheim, 68167 Mannheim, Germany. Tel. +49 621 3832629; Fax: +49 621 3831452.
© 2005 Elsevier B.V., All rights reserved.