Abstract:
Objective To evaluate the toxicity and efficacy of CyberKnife® stereotactic radiotherapy in patients with early lung cancer aged over 70 years.
Methods The data of 34 inoperable elderly patients with early lung cancer (20 with T1 and 14 with T2 tumors) from November 2006 to September 2010 were retrospectively reviewed. Among them, 18 were treated with the Synchrony® Respiratory Tracking System, which requires the implantation of 1-2 gold markers. The other 16 patients were treated with the X-sight® technology. A total dose of 45-60 Gy (median of 60 Gy) was delivered in 3-6 fractions.
Results Complete response was achieved in 25 of the 34 patients (73.5%), and partial response was achieved in the other 9 (26.7%). At a median follow-up of 29 months, the primary tumor control rate was 97.1%. The one-, two-, and three-year disease-free survival rates were 85.3%, 81.6%, and 70%, respectively. The one-, two-, and three-year overall survival rates were 97.1%, 86.6%, and 80%, respectively. Slight fatigue was reported in 31 of the 34 patients (91.1%). Grades I and II radiation pneumonitis were observed in 15 of the 34 patients (44.1%). Grade III radiation pneumonitis was not observed. Pneumothorax requiring tube thoracostomy occurred in one patient (2.9%) following CT-guided fiducial placement.
Conclusion CyberKnife® stereotactic radiotherapy is an effective therapeutic modality for elderly patients with early lung cancer. This therapy can provide a high local-control rate for primary tumors and has minimal toxicity.