Reirradiation for locally recurrent lung cancer previously treated with radiation therapy

Local recurrence of lung cancer after previous external beam irradiation poses some problems for subsequent management. We retrospectively reviewed our series of patients with local recurrence of lung cancer to evaluate the efficacy and safety of reirradiation.

Between 1979 and 2000, 34 patients with local recurrence of lung cancer were retreated with external radiation. There were 29 males and 5 females ranging in age from 38 to 85 years (median: 69 years). At the time of reirradiation, the clinical stage was I or II in 2 patients, IIIa in 5 patients, IIIb in 14 patients, and IV in 13 patients. Reirradiation was performed in 18 patients with the aim of achieving a cure or prolongation of survival (radical treatment), while 16 patients were treated for improvement of their symptoms (symptomatic treatment).

The median interval between the initial radiation therapy and reirradiation was 23 months, with a range of 5 to 87 months. The dose of initial irradiation delivered to the tumor ranged from 30 to 80 Gy (median: 60 Gy) in 1.5--2.0-Gy fractions per day. During reirradiation, it ranged from 10 to 70 Gy (median: 50 Gy) in 1.8--3.0-Gy fractions per day. The cumulative dose delivered to the tumor by treatments of both initial and second irradiation ranged from 56.5 to 150 Gy (median: 110 Gy). A response was observed in 14 out of 18 patients given radical treatment (complete response, 6; partial response, 8). Twelve of the 16 patients (75%) given symptomatic treatment also showed a symptomatic benefit. The overall survival rate after reirradiation was 43% at 1 year and 27% at 2 years, with a median survival time of 8 months. The median survival time after radical treatment was 15 months, with a range of 3 to 58 months, whereas that after symptomatic treatment was 3 months, with a range of 1 to 14 months. Six long-term survivors lived for more than 20 months. Reirradiation-induced toxicity included symptomatic radiation pneumonitis in 19 patients and symptomatic radiation esophagitis in 6 patients. These toxicities were not fatal, and radiation myelopathy was not caused by reirradiation.

Based on this study, external beam reirradiation can achieve satisfactory results for local recurrence of lung cancer provided that attention is paid to the possible hazards.