Pharmacogenetics of Breast Cancer

Pharmacogenetics, generally referred to as the study of genetic variation that gives rise to differing response to drugs, is becoming more relevant in the diagnosis, treatment, and recovery of cancer patients. The problem faced when treating cancer is the outstanding varied efficacy between success and failure. Unpredictability between a population of patients who are affected with the same occurring malignancy can show varying associated toxicities in drug treatment ranging from zero effect through lethal doses. Since the chemotherapeutic agent is often developed to fit the average patient the unfortunate result is that approximately 40% of patients may be receiving the wrong drug. However, using pharmacogenetics there are promising advancements in the development of effective agents which will enable 'personalized cancer chemotherapy' to become routine for the clinical practice. This individualization is most advanced in the field of breast cancer; while many breast oncologists are individualizing techniques based on specific profiles, within 10 years it is likely all breast oncologists will be using RT-PCR, FISH-based multiplexed arrays, or a similar testing regime for patient individualization therapy.