Evaluation of conventional radiotherapy vs. conformal radiotherapy in the treatment of non-small-cell lung cancer after surgical resection

Objective: To compare the survival fractions and radiation-induced complications of conventional radiotherapy (CV) vs. conformal radiotherapy (CF) for non-small-cell lung cancer (NSCLC) after surgical resection. Methods: Between 1990 and 2002, 167 patients underwent post-radiotherapy either CV (n = 90) or CF (n = 77) for pathological IIIA NSCLC at the University of Texas M.D. Anderson Cancer Center. Patients and tumor characteristics were balanced in the two treatment groups. Surgical resection mainly consisted of lobectomy and mediastinal lymph node dissection. In the CV group, postoperative radiotherapy was delivered to 54.3 Gy (range 22-69.6 Gy) in 27 fractions (range 11-58 f) for 56 weeks, while the CF group with RT to 53.9 Gy (range 50-63 Gy) in 26 fractions (range 25-33 f) for 5-6 weeks. Overall survival, disease-free survival, local control and distant metastasis-free survival were calculated using the Kaplan-Meier method. The complications of radiotherapy were also compared between the two groups. The median follow-up duration was 36 months in the CV group while 24 months in the CF group. Results: No statistically significant differences were found in terms of disease-free survival, local-regional control and distant metastasis-free survival in the two treatment groups. However, the overall survival was found statistically significant different in the two groups (P = 0.014). Postoperative radiotherapy complications such as weight loss, skin reaction, dysphagia, and cardiac related complication were similar in the two groups although the lung fibrosis, cardiac complications and hematologic complications were significantly different, and 8 cases of death in the CV group associated with cardiac complications while none was observed in the CF group. Conclusion: The treatment of stage IIIA NSCLC using either CV or CF postoperative radiotherapy resulted in similar outcomes in terms of local control, disease-free survival and most of complications. However, CF could achieve better overall survival and less complications such as lung fibrosis, cardiac complications and hematologic complications. The advantage is worth further observation.