Predictive role of absolute lymphocyte count (ALC) and neutrophil/lymphocyte ratio (NLR) in patients with metastatic non small cell lung cancer (NSCLC) treated with nivolumab: Results of a retrospective monocentric study

Background: Nivolumab is a human monoclonal antibody anti-programmed death receptor-1 (PD-1). It is approved for metastatic NSCLC, unresectable or metastatic melanoma and advanced renal cancer. Despite the improvements achieved in survival and good tolerability, an unmet goal remains the identification of predictive markers to select high responder pts. Data are available on the potential association between lymphocytes and survival in pts with melanoma treated with ipilimumab. Material and methods:We evaluated NSCLC pts treated with nivolumab in second line or beyond.We included in this analysis only pts who received at least two doses of nivolumab and one CT-scan evaluation. Nivolumab was administered intravenously at the dose of 3 mg/kg every 2 weeks until disease progression or unacceptable toxicity. Response rates were evaluated using RECIST 1.1 criteria every 4 cycles.We collected ALC and NLR values at baseline and we sought to correlate ALC and NLR with median progression-free survival (mPFS). Results: Thirty-seven (37) pts were enrolled in the study from May 2015 until April 2016. The last follow-up was April 30th 2016. Thirty-one (31) pts were eligible. Median age was 65 yrs (range 54-79). Twenty-one (21) pts had squamous histology, 10 non-squamous histology. Twenty-nine (29) pts had stage IV disease, two stage IIIA. All pts were pretreated with at least one systemic therapy (range 1-4).We observed 6 (19.4%) partial response (PR), 14 (45.1%) stable disease (SD) and 11 (35.5%) progressive disease (PD), with a disease control rate (DCR) of 64.5%. Median PFS was 3.4 months in the overall population. Median ALC at baseline was 1370/μL (range 680-3850). Twenty-three (23) pts showed higher levels of ALC at baseline. Higher levels of ALC at baseline (>1000/μL) were evident in twenty-three (23) pts and were not associated with improved PFS (p = 0.11). High NRL (≥4) before the first infusion was not associated with improved PFS (p = 0.29). The data on overall survival are immature.We did not observed adverse events of grade 3/4. Conclusions: In our retrospective study, ALC values and NLR at baseline are not associated with improved PFS. Larger prospective randomized studies are warranted in both histologies, squamous and non squamous, to confirm the lack of a potential predictive role of ALC and NLR.