A novel paradigm in the treatment of oligometastatic non-small cell lung cancer

Background: Stage IV non-small cell lung cancer (NSCLC) is thought to uniformly carry a poor prognosis with a median survival of less than 1 year and 5-year survival of less than 5%. In patients with a low volume (i.e.single site) of distant disease, the prognosis is slightly more favorable than that of more advanced (i.e. multiple sites of metastases) disease. For those with limited metastases, we developed a paradigm of adding concurrent chemotherapy and radiotherapy to the primary tumor once the tumor demonstrated chemotherapy sensitivity. Methods: Charts of patients from 1999-2006 with non-small cell lung cancer were reviewed to find those with a single extra-thoracic site of disease treated with combined modality therapy. We found nine patients of 640 who met these criteria. Initial treatment consisted of induction chemotherapy, except for brain metastases which were managed first (n=1). If patients experienced a response to chemotherapy without new metastases, the extra-thoracic site was treated for total control with curative dose chemoradiotherapy to the primary site. Survival, time to progression, and sites of progression were assessed. Results: Median survival was 28 months (95% CI 18-50 mo) with median time to progression of 15 months (95% CI 8-24 mo). All except one patient progressed in the CNS, either with brain metastases (n=7) or leptomeningeal disease (n=1). Conclusions: Such an approach offers the potential for enhanced quality and quantity of survival by incorporating aggressive RT for select patients without disease progression after induction chemotherapy. Patients tended to fail in the CNS, suggesting the importance of continued surveillance of the neuraxis or possibly prophylactic cranial irradiation. Future plans will correlate outcomes with molecular markers.