Continuous, hyperfractionated, accelerated radiotherapy (CHART) versus conventional radiotherapy in non-small cell lung cancer: mature data from the randomised multicentre trial

Background and method: A randomised controlled trial in locally advanced no n-small cell lung cancer (NSCLC), compared CHART which employs 36 fractions of 1.5 Gy 3 times per day to give 54 Gy in 12 consecutive days with conven tional radiotherapy-30 fractions of 2 Gy to a total dose of 60 Gy in 6 week s. A total of 563 patients were entered between April 1990 and April 1995, This report is based upon the data updated to 1 April 1998. Results: The analysis of the mature data shows that the benefits previously reported have been maintained. Overall there was a 22% reduction in the re lative risk of death, which is equivalent to an absolute improvement in 2 y ear survival of 9% from 20 to 29% (P = 0.008) and a 21% reduction in the re lative risk of local progression (P = 0.033), In the large subgroup of pati ents with squamous cell cancer which accounted for 81% of the cases, there was a 30% reduction in the relative risk of death, which is equivalent to a n absolute improvement in 2 year survival of 13% from 20 to 33% (P = 0.0007 ) and a 27% reduction in the relative risk of local progression(P = 0.012). Furthermore, in squamous carcinoma there was a 25% reduction in the relati ve risk of local and/or distant progression (P = 0.025) and 24% reduction i n the relative risk of metastasis (P = 0.043). There was no evidence that C HART gave more or less benefit in any other subgroup. Conclusion: This analysis of mature data confirms that CHART is superior to conventional radiotherapy in achieving local tumour control and survival i n locally advanced NSCLC, This demonstrates the importance of cellular repo pulation as a cause of failure in the radiotherapy of NSCLC. The reduction in the risk of metastasis confirms that improved local tumour control, even in lung cancer, can reduce the incidence of metastasis. This trial shows t hat control of local tumour can lead to an improvement in long term surviva l. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.