Apoptosis and prognosis in cancer: rationale and relevance.

Apoptosis is the biological process by which cells in tissues undergo programmed death. This process is morphologically identifiable and characterised by light and electron microscopy. However, the biological mechanisms underlying this process, as yet, are poorly understood and in need of elucidation. As apoptotic tumour cells can be identified and counted by light microscopy, there has been interest in the application of the enumeration of apoptosis in malignant growths as a putative prognostic marker. This review outlines the rationale for and discusses the relevance of using such an approach in clinical practice.