To determine the risk/benefit profile of stereotactic body radiotherapy in patients with medically unresectable stage 1 non-small cell lung cancer (NSCLC).
We recently completed a phase II study of stereotactic body radiotherapy, which enrolled patients with medically unresectable stage 1 non-small lung cancer. Patients with T1N0 and T2N0 biopsy-proven tumors received 2000 cGy/fraction times 3 fractions and 2200 cGy/fraction times 3 fractions, respectively. Baseline pulmonary function tests (FEV1, FVC, DLCO) and p02 were performed at baseline, 3 and 6 months. Kaplan Meier estimates for overall and disease-free survival were calculated. Treatment toxicity was assessed using standard National Cancer Institute guidelines. In addition an independent safety board determined whether any death was possibly related to the radiotherapy.
A total of 34 T1N0 and 36 T2N0 patients were enrolled from 11/2002 to 08/2004. 30/70 (43%) were on oxygen at baseline. Kaplan Meier estimates indicate a median survival of 32.6 months and actuarial 1-yr overall and disease-free survival of 81.1% and 79%, respectively. As of 5/01/2005, 25 patients have died with 5 deaths felt to be possibly related to the radiotherapy. After a median follow-up of 23 months, 2 local, 4 regional and 2 distant recurrences occurred. 14 patients developed a decrease in pulmonary function and 3 patients suffered radiation fibrosis. Baseline pulmonary function values were: FEV1 1.12 liters, FVC 2.31 liters, DLCO 11.17 and pO2 72.6. At 3 months values were: FEV1 1.19, FVC 2.54, DLCO 10.67 and pO2 67.7. At 6 months post radiotherapy values were: FEV1 1.14, FVC 2.54, DLCO 10.67 and pO2 67.6.
In this fragile population, high dose stereotactic body radiotherapy for medically unresectable stage 1 NSCLC appears to have a favorable benefit/risk profile. Specifically, there was no significant decrease in pulmonary function for the overall population at 3 and 6 months.
Frail patients with medically unresectable stage 1 NSCLC appear to tolerate high doses of targeted radiotherapy. This novel therapy should be further studied in a large multicenter trial.
Mark Williams, None.