Prognostic Variables Associated With Improved Outcomes in Patients With Stage III NSCLC Treated With Chemoradiation Followed by Consolidation Pembrolizumab: A Subset Analysis of a Phase II Study From the Hoosier Cancer Research Network LUN 14-179.

INTRODUCTION

The Hoosier Cancer Research Network (HCRN) LUN 14-179 is a phase II trial of consolidation pembrolizumab after concurrent chemoradiation for the treatment of patients with stage III non-small-cell lung cancer (NSCLC). Time to metastatic disease or death (TMDD), progression-free survival (PFS), and overall survival (OS) appear to be superior to that in historical controls of chemoradiation alone. Unfortunately, not all patients benefit from consolidation immunotherapy. We performed a univariate analysis to evaluate variables associated with PFS, metastatic disease, and OS.

PATIENTS AND METHODS

We conducted a retrospective analysis of patients enrolled in HCRN LUN 14-179. Data collected included age, sex, stage, smoking status, programmed death ligand 1 status, Grade (G) ≥ 2 versus G ≤ 1 adverse event, G ≤ 2 versus G ≥ 3 pneumonitis, duration of pembrolizumab (< 4 vs. ≥ 4 cycles), chemotherapy regimen, performance status 0 versus 1, time to start pembrolizumab (4-6 vs. 6-8 weeks from radiation), volume of lung receiving at least 20 Gy of radiation (V; < 20% vs. ≥ 20%). Univariable Cox regression was performed to determine the variables associated with 3 end points: TMDD, PFS, and OS.

RESULTS

From April 2015 to December 2016, 93 patients were enrolled and 92 were included in the efficacy analysis (1 patient was ineligible). For TMDD, improved outcomes might be associated (P < .1) with stage IIIA and ≥ 4 cycles of pembrolizumab. For PFS, improved outcomes (P < .1) might be seen for ≥ 4 cycles of pembrolizumab, stage IIIA and V < 20%. For OS, improved outcomes (P < .1) might be seen for stage IIIA and ≥ 4 cycles of pembrolizumab.

CONCLUSION

Stage IIIA and longer duration of pembrolizumab treatment might be associated with prolonged TMDD, PFS, and OS for patients with stage III NSCLC treated with chemoradiation followed by pembrolizumab.