Novel Approaches Using Radiation Therapies

Abstract

New information has recently emerged concerning the role of adequate local control of breast cancer through the use of locoregional radiation therapy in conjunction with adjuvant cytotoxic chemotherapy. These data support the proposition that achieving initial local control is important to maximize breast cancer cure rates. At the same time it is important to minimize or avoid potential side effects of breast cancer radiation therapy, particularly cardiac side effects which may compromise overall survival. Novel approaches such as three-dimensional treatment planning can be of help clinically to quantitate such effects and to optimize therapy in individual patients. The increasing use of routine postoperative radiation therapy following conservative breast surgery highlights the need to identify those patient subsets that are likely to benefit from treatment. Studies that have aimed, using hitherto identified risk factors, to identify subgroups of patients at such low risk of breast recurrence that radiation therapy may not be warranted, have in general produced disappointing results. Searching for potential treatment-predictive assays may prove to be a more fruitful approach. Since the response to radiation therapy is probably related, at least in part, to the intrinsic radiosensitivity of the tumor cells, novel treatment-predictive assays based on molecular biology may perhaps turn out to be clinically useful. This paper will briefly review some recent information from the aforementioned fields of research.