Genetic aberrations as the targets of oncology research: Involvement of paraffin-embedded tissues.

Cancer is a complex and heterogeneous group of diseases which have been generally classified by their clinical and histopathological features. The genomes of cancer cells are altered by diverse mechanisms and these genetic aberrations lead to a variety of pathological changes. A number of technological advances have allowed us to analyze the cancer genome by various '-omics' techniques, and have accelerated the exploration for the primary genetic aberrations that drive cancer. The state-of-the-art technologies that have developed over the past few decades have enabled researchers to catalogue these genetic aberrations in detail. These aberrations include changes in gene structure and the copy number, mutation, and modification of DNA. Simultaneously, there have been significant achievements in the translation of the genomic discoveries "from the bench to the bed", which have provided valuable contributions to the progress in cancer therapy. One technology that has been central to these research efforts has been the histopathology of cancer specimens, particularly the use of formalin-fixed, paraffin-embedded tissues. In this overview, we consider the development of oncology research from the past to current efforts, and highlight the roles of histopathology and paraffin-embedded tissues in these efforts.