Evaluation of prognostic factors in prostate cancer with partial least squares analysis

Objective: This study was carried out to explore the capability of partial least squares (PLS) analysis, a multivariate projection method, in the eval uation of investigative prognostic biomarkers. Material and Methods: Using PLS analysis, survival and life expectancy were prognosticated in 53 patien ts with prostate cancer treated with transurethral resection. The age of th e patient, stage and grade of the tumours, and immunoreactivity in the tumo urs for p53, Bcl-2, and TGF-beta 1 and its receptors type I and type II (TG F beta-RT and TGF beta-RII), and markers for proliferation, Vascular densit y, and macrophage density were included as prognostic factors in the analys is. Results: The prognostic impact of the factors, in decreasing order, was tumour grade, proliferation, stage, vascular density, TGF beta-RI, metasta sis, TGF-beta 1, and TGF beta-RII. Macrophage staining, p53, BcI-2, and pat ient age did not contribute to the model. The model explained 62% of the to tal variance in survival, and the standard deviation of error of prediction was 29 months. Conclusions: PLS analysis may become a useful tool for eval uation of putative prognostic factors.