NEW MODALITIES AND EVOLUTION OF RADIATION TECHNIQUE FOR LOCALISED UNRESECTABLE NON SMALL CELL LUNG LANCER

Purpose: To describe the new modalities and the evolution of radiation techniques for localised unresectable nonsmall cell lung cancer. Material and methods: Major European and American contributions to treatment strategies using radiation alone or combined with chemotherapy or other adjuvants for locally advanced or medically inoperable early stage nonsmall cell lung cancer have led to improve local control and survival with a paradigm shift. The results of the clinical research over the past 2 decades could be reviewed. Results: Radiation therapy is an important tool in locoregional treatment for unresectable nonsmall cell lung cancer. After "standard" fractionation radiation therapy alone, the control of local disease and distant micrometastases remains poor. Primary chemotherapy followed by radiation therapy provide a limited improvement in survival with a benefit of 4-6% at 2 years. This survival benefit is essentially due to an increased control of distant micrometastases without a significant reduction in the risk of local recurrence. Over the past decade, different approaches have been attempted in order to improve the local control: three-dimensional conformal radiotherapy, altered fractionation radiation therapy, concomitant radiotherapy and chemotherapy, combined non cytotoxic radiosensitizers and radiation therapy , and high dose-rate endoluminal brachytherapy. Through results of numerous phase I/II studies of these new treatment approaches suggest better local control and survival. Few phase III studies have been reported. Conclusion: The new radiation techniques and combined treatment modalities are promising. However, numerous randomized trials are needed to determine optimal treatment according to stage, tumor and involved mediastinal lymph node sites, and performance status.