Gemcitabine-induced thrombocytosis as a potential predictive factor in non-small cell lung cancer: analysis of 318 patients

Introduction: In spite of the progress in the treatment of non-small-cell lung cancer (NSCLC), the majority of patients with advanced disease still receive chemotherapy. Gemcitabine alone or combined with a platinum compound is a valid option. Thrombocytosis is a recognized prognostic factor in lung cancer and an adverse event that may occur during gemcitabine infusion.\Methods: We retrospectively evaluated all patients with NSCLC treated with first-line gemcitabine-based chemotherapy in two Italian hospitals. We assessed the onset of thrombocytosis within the third cycle of therapy and the relation between thrombocytosis and survival.Results: We included 318 patients. Thrombocytosis occurred in 156 patients (49.1%). Median progression-free survival (PFS) was 5.6 months (95% CI, 4.7-6.9 months) in patients who developed thrombocytosis versus 6 months (95% CI, 5.1-7.2 months) in patients without thrombocytosis (p = 0.21). Median overall survival (OS) was 11.2 months (95% CI, 9.8-13.4 months) in patients with thrombocytosis versus 12 months (95% CI, 10.1-14.4 months) in patients without thrombocytosis (p = 0.25). We observed no difference in terms of PFS or OS according to age, sex, stage, chemotherapy (single-agent versus combination chemotherapy) and thrombocytosis.Conclusions: Thrombocytosis is neither a prognostic nor a predictive factor for PFS or OS in patients with advanced NSCLC treated with first-line gemcitabine-based chemotherapy.