Retrospective review of concurrent chest radiation and chemotherapy (CRT) in newly diagnosed stage IV non-small cell lung cancer (NSCLC) with oligometastatic disease (OM) treated with stereotactic radiation.

Abstract

e20539 Background:The primary treatment for patients (pts)with stage IV NSCLC is palliative chemotherapy (CT), with a median OS of approximately 10-12 months, and 5-year survival of ~2%. Several studies have demonstrated that pts with a lung nodule with a solitary brain or adrenal metastasis can achieve relatively high 5-year survival rates with resection of the metastasis and the lung nodule. Studies have also demonstrated that OM can be effectively treated with stereotactic body radiation (SBRT) or stereotactic radiosurgery (SRS) to the brain. We hypothesize that treatment of OM with SBRT and/or SRS and treatment of the thoracic disease with CRT will improve survival over palliative chemotherapy alone. Methods:A retrospective review of charts in the RADTRACS database at the Univ of Florida was conducted between 1/1/2010 - 6/30/2015 to identify pts with newly diagnosed stage IV NSCLC with 5 or less OM at diagnosis that were treated with concurrent CT and definitive RT (60-66 Gy) to the primary lung mass in addition to SRS and/or SBRT to the OM. Date and site of first progression, and date of death/last follow-up were noted. Endpoints included median progression free survival (PFS) and median overall survival (OS). Results:26 pts met these criteria. 20 pts (77%) had recurrence of disease after treatment with CRT + SRS/SBRT. Median PFS was 6 months, and median OS was 14.4 months. Of the 20 recurrences, 10 (50%) were in the brain, while 10 (50%) were in non-CNS sites. One year OS was 60% and 3-year survival was 33% in our patients. When pts with CNS OM at diagnosis were compared to non-CNS OM, PFS (5.5 vs 5.8 months, respectively, p > 0.05) and OS (16.6 vs 13.8 months, respectively, p > 0.05) were similar. 8/12 CNS OM pts progressed in the brain while only 3/9 non-CNS OM progressed in the brain. Of the 5 patients with no progression, 4/5 had non-CNS OM at diagnosis. Conclusions:When compared to standard palliative CT where median OS 10-12 months, median OS was 14.4 months in our pts treated with CRT + SBRT/SRS. This data suggests a possible role for more aggressive treatment of stage IV NSCLC pts with SBRT/SRS to OM and definitive chest CRT.