[Current status and problems of tailor-made medicine in anticancer therapy]

Tailor-made medicine is a key concept in achieving a successful outcome for individual patients with malignant disease. Identifying the appropriate patient, i.e., "How to select patients", is the first concept of tailor-made medicine. In recent years, molecular target drugs have been developed rapidly and over a broad spectrum. The candidate patients for drugs are selected by particular biomarkers based on theoretical evidence. Moreover, conventional individualized methods such as TNM classification, pathological findings and patient background including performance status, and organ functions, are also important to correctly identify the patients. Identifying the appropriate therapy, i.e., "How to treat", is the next concept. Drug sensitivity tests and prediction models using DNA micro array are still under development and not available at bedside. Chemotherapy drug dosages are adjusted according to body surface area with a lack of scientific data. There have been some attempts to establish calculation formulas for modification of drugs. The Calvert formula is the best-known, however, it may not be used correctly in Japan because of the difference in the methods for estimating creatinine as well as ethnic differences. pharmacogenomics/pharmacogenetics is the front-line approach of modern chemotherapy that analyzes genomic information and pharmacokinetic/pharmacodynamic findings. This approach is achieving adaptable results for cancer treatment practice. Finally, for tailor-made medicine, we must develop genomic approach in both evaluating tumor characteristics and establishing adequate therapy, and have to combine all possible information including conventional TNM classification and pathological findings.