The role of palliative thoracic radiotherapy in non-small cell lung cancer

Abstract

Non-small cell lung cancer is the most common cause of cancer death in both males and females. Despite this high incidence and mortality, comparatively little research has addressed the palliative treatment of thoracic symptoms. Until recently, information regarding the indications and effectiveness of radiation in this setting was obtained from retrospective reviews of single institutional experiences. More recently, three major randomized trials from the UK Medical Research Council (1991, 1992, 1994) have addressed the use of external beam radiation in randomized comparisons of different dose and fractionation strategies for patients with non-small cell lung cancer and symptoms due to intra-thoracic tumor. These studies show that shorter fractionation schemes provide equivalent palliation and essentially equivalent survival in the patient groups studied. Moreover, they provide estimates of the probability of successful palliation of common symptoms, and estimates of the toxicity of each regimen. A panel of oncologists with expertise in radiation oncology, medical oncology and epidemiology discussed the above trial results and a literature review. The panel concluded that radiation was indicated in the palliation of hemoptysis, chest pain, dysphagia, and dyspnea, and that the results of the MRC studies provided reasonable estimations of the efficacy and toxicity of radiation in this setting. These studies show that symptoms are more often than not improved with palliative radiotherapy (symptom improvement rates ranged from about 50 to 85%) and that palliation lasted for a substantial portion of the patients' remaining survival. The panel could not reach uniform consensus on the appropriate fractionation for radiation given with palliative intent. The panel agreed that favourable patients with stage IIIB NSCLC should be offered combined modality therapy with the intent of prolonging survival, and that patient preferences regarding the risks and benefits of this therapy should be considered. Further study was recommended, namely, a randomized trial evaluating five fractions of radiation vs a single fraction, using patient-based evaluation of palliation. The panel also recommended phase II development of a combined chemotherapy and low-dose radiation protocol appropriate for future study.