Escalated hyperfractionated accelerated radiation therapy combined with chemotherapy for stage IIIB non-small cell lung cancer

Abstract

To evaluate the therapeutic effect and acute side-effect of escalated hyperfractionated accelerated radiation therapy (EHART) combined with chemotherapy for stage IIIB non-small cell lung cancer (NSCLC). From Aug. 1998 to Aug. 2001, a prospective trial for NSCLC was carried out in 112 patients with stage IIIB. These patients were nonrandomly divided into 2 groups: conventional fractionated radiation therapy group (CFRT 65 cases) and EHART group (47 cases). The CFRT patients were treated by 1.8-2 Gy/fraction per day, 5 treatment days per week; the total doses received in center of tumor were 54-70 Gy /27-40 fractions/37-85 days, the median was 60 Gy/30 factions/43 days. The EHART patients were treated by escalated doses: In the first and second weeks, 1.2 Gy/fraction twice a day was given, then 1.3 Gy , 1.4 Gy , and 1.5 Gy from third to fifth weeks respectively, twice fractions a day (over 6 hours interval), 5 treatment days each week, the total doses were 60-66 Gy/46-50 fractions/30-45 days, the median was 66 Gy /50 fractions/34 days. Radiation fields just covered the tumor mass which were determined by thoracic CT with 1.5 cm margins. A total of 4-6 cycles chemotherapy with MVP regimen mostly was delivered before (1-2 cycles) and after (3-5 cycles) radiotherapy. Each patient was followed up for 1 year. Seven cases were excluded from EHART, twelve from CFRT. There were 93 patients to be evaluated. The immediate response rate of tumor by EHART and CFRT was 72.5% and 64.2% respectively (Chi-square=1.02, P=0.346). The 1-year survival rate was 60.0% and 47.2% respectively (Chi-square=2.56, P=0.107), and the local control rate was 67.5% and 52.8% respectively (Chi-square=3.01, P=0.085). The incidence and degree of acute radiation esophagitis in EHART were more severe than that in CFRT (Chi-square=5.02, P=0.025). The treatment effect by EHART for stage IIIB NSCLC is encouraging and its toxicities could be tolerated by most of patients. It is worthy of further study on survival rate and late complications in long term.