1990P - Leukocytosis as a negative prognostic factor in patients with lung cancer: Which subpopulation of leukocytes is responsible?

Leukocytosis is common in patients with malignancies and might be a negative prognostic factor in lung cancer (LC). Leukocytes are, however, a heterogenous population of blood cells. Therefore, subpopulation of leukocytes responsible for this effect should be identified. It is presumed that neutrophilia and lymphocytopenia might be a negative factor in patients with lung cancer. Leukocyte, absolute neutrophil, lymphocyte, eosinophil, basophil and thrombocyte count were determined before beginning of treatment in patients with LC. Patients with recent bleeding, elevated CRP or treated with best-supportive care were excluded. The impact of leukocytosis, neutrophilia, lymphocytopenia, eosinophilia and basophilia on progression- free survival (PFS) was determined. Neutrophils to lymphocytes ratio (NLR) at various cut-offs were determined along with platelets to lymphocytes ratio (PLR) and their effect on PFS was assessed. Kaplan- Meier and Cox- regression statistical analysis were used. 200 patients were examined in our retrospective study. Median PFS was 7.41 months. Leukocytosis and neutrophilia significantly worsened PFS in patients with LC [HR 0.5200, (95%CI 0.3684 to 0.7340), P