New techniques make it possible for investigators to examine and sometimes quantify various aspects of nuclear morphology and function; now they can derive clinically and biologically useful information about the nucleus. This book draws together a series of techniques which have been successfully applied to the study of the nucleus of tumour cells. These are of fundamental importance to researchers in tumour histopathology and medical oncology. Detailed reviews are given of various aspects of the morphology, ploidy and karyotypic status and function of the nuclei in the cells of tumours and preneoplastic lesions. Topics covered include nuclear morphology in tumour diagnosis, the ultrastructure of the nucleus, karyotypic analyses of solid tumours, flow cytometric assessment of nuclear ploidy and other parameters, histomorphometry of the nucleus, and in situ hybridisation.