Treatment-naive patients with histologically confirmed NSCLC , stage IIIA/IIIB , received either 39Gy in 13 fractions as RT alone ( arm A , n = 31 ) or 2-3 platinum-based CHT cycles followed by 10Gy in a single fraction or 16Gy in 2 fractions separated by one week ( arm B , n = 34 ) .