Tong YS, et al. - Researchers examined 286 patients with stage II–IVa esophageal squamous cell carcinoma (ESCC) treated with concurrent chemoradiotherapy (CCRT) to assess the association of lymphopenia with treatment response and tumor progression. At initial diagnosis, lymphopenia was observed in 44 patients. Findings revealed a significant association of treatment-related lymphopenia with lack of clinical complete response in multivariate analysis. Independent predictors of treatment-related lymphopenia were older age, lower tumor location, greater tumor length, and larger planning target volume. They found that poor treatment response in ESCC was independently predicted by treatment-related lymphopenia during CCRT.