Treatment-related Lymphopenia in Patients With Stage III Non-Small-Cell Lung Cancer

This study sought to estimate the severity, etiology, and clinical importance of treatment-related lymphopenia in patients with stage III non-small-cell lung cancer.Serial lymphocyte counts and survival were analyzed retrospectively in 47 patients accounting for known prognostic factors.Total lymphocyte counts (TLCs) were normal before therapy and did not change following neoadjuvant chemotherapy. Following radiation, TLC fell by 67% (median 500 cells/mm(3), p <.00001). Multivariate analysis revealed an association between severe TLC and survival (HR 1.70, 95% CI: 0.8-3.6).Rapid and severe lymphopenia occurred in 50% of patients following radiation which was associated with reduced survival.