The present invention relates to a method for classifying a prostate cancer in a subject, the method comprising the steps of a) determining a gene expression level or gene expression pattern of the genes F3 and IGFBP3 in a sample from the subject and b) classifying the tumor by comparing the gene expression level determined in a) with a reference gene expression of the same genes in reference patients known to have a high risk or low risk tumor respectively. In addition the invention relates to a method for determining prognosis of a subject diagnosed with prostate cancer, a method for making a treatment decision for a subject diagnosed with prostate cancer and a solid support or a kit for classifying a tumor in a subject diagnosed with prostate cancer.