This document provides an overview of Biology of Functions (BoF) and its application to cancer assessment and treatment. It discusses some of the shortcomings of traditional cancer research and screening/prevention methods. BoF quantifies the functional abilities of the organism through indices defined by mathematical relationships between blood analysis data. It provides a dynamic, integrated assessment of cancer risk and progression based on endocrine, metabolic, immunological and other functional factors. A case study is then presented of a child with glioblastoma multiforme treated using an individualized approach based on BoF assessments over time.