Postoperative radiation therapy for lung cancer: where do we stand?

Lung cancer is the leading cause of cancer mortality in the United States. Local recurrence after surgery for operable disease has long been recognized as a hindrance to long-term survival. Postoperative radiation therapy was logically explored as a means to improve local control and survival. Multiple randomized trials were conducted, many showing improved local control, but none demonstrated a statistically significant survival benefit. In fact, a meta-analysis showed a rather large survival detriment, presumably from treatment-related complications. Radiation therapy has evolved over the years, and more modern treatment planning and delivery has the potential to treat sites deemed at high risk of recurrence while limiting the dose to critical intrathoracic structures, which should decrease the risk of treatment-related complications. Recent studies have supported this supposition. Similarly, since cancer is often a systemic disease, local control will become a more pressing issue as systemic micrometastatic disease is eradicated with effective chemotherapy. Unfortunately, randomized trials testing the effectiveness of modern postoperative radiation therapy in the chemotherapy era have not been performed. Clinicians must therefore counsel patients regarding the risk of disease recurrence after surgery, the potential but unproven benefit of postoperative radiation therapy, and the possibility of treatment-related complications.