Precision Medicine in Oncology and Cancer Therapeutics

The definition of precision medicine changed in the twenty-first century several times due to advances in molecular biology, genomics, biotechnology, and data science. Oncology is a model for other medical specialties for the early transition to precision medicine. The understanding of cancer has evolved over time: from macroscopic descriptions of localization moving to microscopic descriptions, molecules, and then interaction between molecules. Now we are witnessing the transition toward understanding cancer as a continuum by capturing spatial and temporal tumor heterogeneity. By integrating multiple data sources (multiomics), each case of cancer can be approached as if it represents a separate disease (N of 1). The notion of precision oncology takes on new meanings as new levels of data are added to the understanding of cancer, from complex biological, digital, clinical, behavioral, and environmental data. In this chapter, we followed transformations in oncology, from a historical perspective and also from the perspective of the revolution in omics sciences and data sciences, identifying four distinct stages, all part of the concept of precision oncology. Precision oncology 1.0 starts from the symptoms and everything that can be seen with the doctor’s naked eye, and the resolution increases through the development of microscopy, biochemistry, cell biology, and the birth of pharmacogenetics. In precision oncology 2.0, diseases begin to be reclassified starting from molecules to symptoms; it is the stage in which the notions of biomarkers and targeted therapies gain momentum. Precision in this period is based on deciphering the structure of DNA and the early stages of biotechnology development. Precision oncology 3.0 is dominated by the development of high-capacity genomic sequencing technologies, with comprehensive genomic profiling, shifting the gears toward genomic medicine and modern biotechnology, which today underpins the development of most drugs. In precision oncology 4.0, the characterization of cancer will be of very high resolution (single-cell multiomics); it will be dynamic (the transition from pre-cancer to cancer will be predictable), comprehensive (multiomic biomarkers, spatial genomics, functional tests, organoid-driven precision medicine, multitarget drugs, hybrid pharmacological constructs), and data-driven (network medicine, AI, machine learning-decision-making tools, human digital twins). Oncology 4.0 illustrates the Fourth Industrial Revolution, accelerated by the COVID-19 pandemic.