40. Comparison of two accelerated radiotherapy regimens in management of locally advanced non-small cell lung cancer (NSCLC) – hyper-fractionated conventional accelerated radiotherapy (RAHIP) and accelerated conformal radiotherapy with concurrent boost (RT-BOOST)

Abstract

Background Repopulation during radiation therapy may compromise the results of the treatment of NSCLC. In spite of the data showing an improvement of therapeutic ratio with shortening of the total treatment time, there is no univoa.ue way of doing, it. Current study was conducted to compare two different regimens of accelerated radiotherapy. Material/Methods From March 1999 to November 2000 forty patients with stage III NSCLC were included. Twenty-eight pts. (70%) received 3–4 cycles of induction chemotherapy (cis-platinum, vepeside). Twenty-six p. were treated according to RAHIP schema, 14 pts. according to RT-BOOST schedule. RAHIP consisted in radiotherapy twice-daily delivered: first week: 2×1,20 Gy “elective fields”, the remaining three weeks 1,80 Gy “elective fields” and 1,20 Gy boost on involved areas by oblique fields. Total dose was 57 Gy. Conventional treatment techniques were employed. RT-BOOST technique was conformally planned and delivered, total dose was 56,7 Gy in 21 fractions (per fraction: 1,9 Gy to limited elective areas and concurrent boost of 0,8 Gy to the GTV) and 26 days. Results With a follow-up period ranging from 1 to 19 months, there is no difference in the compliance with the treatment-plan, treatment tolerance and response rate in the two analysed groups. In all but two patients treatment plan was realised. In RT-BOOST group treatment was discontinued in one patient, because of prolonged III° EORTC/RTOG oesophageal toxicity. In RAHIP group in one patient treatment was prolonged by 10 days because of pneumonitis (II° lung toxicity). One case of III° oesophageal toxicity was observed in each group. There was no increase in toxicity among patients receiving chemotherapy before radiotherapy. The response rate was similar in both analysed groups (RAHIP: 73% PR, 7,5%, CR; RT-BOOST: 65% PR, 7% CR). Estimated by Kaplan-Meier actuarial one-year survival rate method was 66% and actuarial one-year progression free-survival rate was 58% for the entire group. Conclusions Preliminary results of accelerated radiotherapy for locally advanced NSCLC seem promising. Additionally a good compliance with the treatment in both groups allows to work out a phase III study dealing with this problem.