P2.17-25 Post-Treatment Neutrophil to Lymphocyte Ratio in Locally Advanced NSCLC Patients Treated with Concurrent Chemoradiotherapy

Abstract

We aimed to investigate the relationship between NLR and prognosis in patients with locally advanced NSCLC who received concurrent chemoradiotherapy as the first line treatment. We retrospectively analyzed 62 patients with locally advanced NSCLC treated with definitive CCRT between 2008 and 2016 at Seoul St. Mary’s hospital. We excluded patients who received induction chemotherapy to eliminate their influence on NLR. CCRT consisted of weekly chemotherapy using paclitaxel/carboplatin, docetaxel/cisplatin, docetaxel/carboplatin, and etoposide/cisplatin. Radiotherapy was performed with intensity-modulated radiotherapy (IMRT) or three-dimensional conformal RT (3D-CRT). The median radiation dose was 66 Gy in 33 fractions (range, 52 – 70 Gy). The pre-CCRT NLR was calculated from the nearest CBC within 1 week before CCRT and post-CCRT NLR was calculated using CBC 4 weeks after CCRT. Change of NLR before/after CCRT was also analyzed. The maximally selected log rank test was used to acquire the most significant NLR level related with overall survival (OS). The pre-, post-CCRT NLR, and NLR change (post-CCRT NLR/pre-CCRT NLR) cut-off levels were 1.9, 3.15, and 1.6, respectively. The median follow up duration was 11 months (range, 2–71 months). The 3-year OS, loco-regional progression free survival (LRPFS), and distant metastasis free survival (DMFS) were 45.4%, 9.3%, and 6.2%, respectively. The post-CCRT NLR and NLR change were significantly associated with OS and LRPFS. The high post-CCRT NLR group (> 3.15) showed significantly worse OS and LRPFS compared to the low post-CCRT NLR group (≤ 3.15) (3-year OS: 21.2% vs. 46.9%, p=0.005; median LRPFS: 7.7 months vs. 11.3 months, p=0.04). The high NLR change group (> 1.6) had significantly worse OS and LRPFS than the low NLR change group (≤ 1.6) (3-year OS: 32.7% vs. 36.9%, p=0.026; median LRPFS 7.7 months vs. 10.4 months, p=0.025). The pre-CCRT NLR showed a marginally significant difference in OS (3-year OS: 29.1% vs. 56.9%, p=0.062). There was no correlation between NLR and DMFS. The pre-, post-CCRT high NLR and increased NLR after CCRT are associated with poor prognosis of survival in patients for locally advanced NSCLC. An elevated NLR after CCRT might be an indicator of an increased risk of loco-regional failure. Further studies are needed to confirm the predictive value of NLR and the treatment strategies using NLR.