[Middle fraction radiotherapy for non-small cell lung cancer. Effect of increasing the total focal dose].

ABSTRACT

There were evaluated retrospectively the immediate and long-term results of radiotherapy in 259 patients with non-small cell lung cancer stages I-IV who had contraindications to surgery. Irradiation was carried out by middle fraction with single focal dose 3-4 Gr. We compared the results of treatment in two groups of patients differed in volume of total focal dose I group (124 patients)--45 Gy, II group (125 patients)--60 Gy. An increase of total focal dose from 45 Gy to 60 Gy did not lead to an increase of the toxicity to vital organs including patients older than 60 years and patients with initially poorer somatic status. Disease-free survival significantly increased in total in the group with total focal dose 60 Gy and predominantly in tumors over 5 cm, in patients with ECOG 2-3 and in III-IV stage disease. An increase of total focal dose to 60 Gy in the group was significantly prolonged survival without local recurrences from 37% to 50% and by one-third reduced the frequency of locoregional recurrences. Identified benefits in overall and disease-specific survival the groups of non-small cell lung cancer patients with total focal dose 60 Gy compared with a group of non-small cell lung cancer patients who received radiotherapy in total focal dose 45 Gy at terms more than 5 years did not reach statistical significance.