Identification of prognostic tumor markers is a main strategy for planning treatment and predicting outcome of patients with various malignancies. This article reviews a panel of proliferation markers, hormone receptors, oncogene products and apoptosis regulators that have shown potential as prognostic indicators in common human cancers. At present, steroid receptors and the c-erbB-2 gene are the only tissue-based markers accepted in clinical practice, having an established role in breast cancer prognosis. Other markers e.g., the p53 gene, look promising as prognostic factors in different kinds of cancer.