Stereotactic Body Radiation Therapy for Early-Stage Non–Small-Cell Lung Carcinoma: Four-Year Results of a Prospective Phase II Study
Received 4 September 2008; received in revised form 24 November 2008; accepted 27 November 2008. published online 02 March 2009.
Purpose
The 50-month results of a prospective Phase II trial of stereotactic body radiation therapy (SBRT) in medically inoperable patients are reported.
Methods and Materials
A total of 70 medically inoperable patients had clinically staged T1 (34 patients) or T2 (36 patients) (≤7 cm), N0, M0, biopsy-confirmed non–small-cell lung carcinoma (NSCLC) and received SBRT as per our previously published reports. The SBRT treatment dose of 60-66 Gy was prescribed to the 80% isodose volume in three fractions.
Results
Median follow-up was 50.2 months (range, 1.4–64.8 months). Kaplan-Meier local control at 3 years was 88.1%. Regional (nodal) and distant recurrence occurred in 6 (8.6%) and 9 (12.9%) patients, respectively. Median survival (MS) was 32.4 months and 3-year overall survival (OS) was 42.7% (95% confidence interval [95% CI], 31.1–54.3%). Cancer-specific survival at 3 years was 81.7% (95% CI, 70.0–93.4%). For patients with T1 tumors, MS was 38.7 months (95% CI, 25.3–50.2) and for T2 tumors MS was 24.5 months (95% CI, 18.5–37.4) (p = 0.194). Tumor volume (≤5 cc, 5–10 cc, 10–20 cc, >20 cc) did not significantly impact survival: MS was 36.9 months (95% CI, 18.1–42.9), 34.0 (95% CI, 16.9–57.1), 32.8 (95% CI, 21.3–57.8), and 21.4 months (95% CI, 17.8–41.6), respectively (p = 0.712). There was no significant survival difference between patients with peripheral vs. central tumors (MS 33.2 vs. 24.4 months, p = 0.697). Grade 3 to 5 toxicity occurred in 5 of 48 patients with peripheral lung tumors (10.4%) and in 6 of 22 patients (27.3%) with central tumors (Fisher's exact test, p = 0.088).
Conclusion
Based on our study results, use of SBRT results in high rates of local control in medically inoperable patients with Stage I NSCLC.
∗Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN
†Department of Radiation Medicine, University of Kentucky, Lexington, KY
‡Division of Biostatistics, Indiana University School of Medicine, Indianapolis, IN
§Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX
‖Division of Pulmonology, Indiana University School of Medicine, Indianapolis, IN
Reprint requests to: Achilles J. Fakiris, MD, Department of Radiation Oncology, Indiana University School of Medicine, 535 Barnhill Dr., RT 041, Indianapolis, IN 46202. Tel: (317) 274-2524; Fax: (317) 274-2486
Accepted for oral presentation at American Society of Therapeutic Radiation Oncology 2008.
ABSTRACT