This document discusses the potential role of nutrition and phytotherapy in oncology. It notes that about 50% of cancers cannot be cured by chemotherapy alone, and resistance accounts for treatment failure in about 70% of patients. Nutraceuticals and phytochemicals may help treat side effects of chemotherapy, radiotherapy, and have proapoptotic, immune function improving, and antimetastatic effects. The document discusses various plants and supplements that may have applications in cancer prevention, treatment of side effects from conventional therapies, and as adjunctive treatments. It summarizes research on melatonin, inositol, and the role of diet and various plant compounds in influencing cancer processes.