CTLA4 and non-small cell lung carcinoma: Our finding of the increased CTLA-4 expression by CD8+ T cells, which likely reflects enhanced T cell activation, is in line with the results of a previous study reporting increased CTLA-4 expression by peripheral T cells, including CD8+ T cells, in patients with non-small cell lung cancer who received a combination of chemotherapy and anti-CTLA-4 ipilimumab (14).