Long-term effects of stereotactic ablative radiotherapy for patients with NSCLC

The authors examined the long-term effects of stereotactic ablative radiotherapy (SABR) in treating patients with stage 1 non-small-cell lung cancer (NSCLC). They concluded that SABR is both safe and effective in the long-term.

SABR is a type of radiation used to treat inoperable early stage NSCLC. Studies have shown its effectiveness to be comparable to surgery. However, studies on the effectiveness and toxic side effects of SABR were based on short term follow-ups. There is limited data available on long-term (greater than 5 years) effects after treatment. Therefore, the long-term effectiveness of SABR is unknown.  

This trial examined the long term effectiveness and toxicity of SABR for treating stage 1 NSCLC cancer. 65 patients were treated with SABR. Patients then underwent follow-up every three months for the first two years, every six months for the next three years, then annually after that. The average length of follow-up was 7.2 years.

18 patients had disease recurrence after an average of 14.5 months. Five of these had local recurrence (cancer coming back in the same place) while 8 had regional recurrence (near the initial region) and 8 had distant metastases (spread to other parts of the body).

Average progression free survival (time from treatment until disease progression) was 49.5% after 5 years and 38.2% after 7 years. Overall survival (beginning treatment until death from any cause) was 55.7% after 5 years and 47.5% after 7 years.

Twelve patients developed a second primary lung cancer (the presence of a second unrelated cancer in the lung). Following more treatment, 10 of these patients did not have a further recurrence.

Three patients experienced serious side effects including rash, chest wall pain, and infection of the air sacs in the lungs. 

The authors concluded that SABR is safe in the long-term and has good local control. They also recommended surveillance for second primary lung cancer following treatment.