[Contribution of molecular and genetic biology in oncology]

During the last decades, major medical advances have been made in the understanding of cancer biology and led to the appearance of new diagnostic tools and development of innovative therapeutics. Some basic concepts in molecular medicine, oncogenes and tumour-suppressor genes are reviewed. Special topics are devoted to Ras, erbB2, p 53 and characteristical gene rearrangements, such as bcr-abl, RARA-PML, VDJ, bcl2-IgH. The greater knowledge of the molecular etiology of cancer will contribute to disease screening, diagnosis, staging and therapy, detection of residual or recurrent disease, and development of new treatments, such as gene therapy or drugs targeted to oncogene products.