ARG1 and melanoma: In patients with non-small cell lung cancer (NSCLC), the presence of peripheral ARG1+ neutrophils increases with the tumor stage in treatment-naive patients and negatively correlates with the proportion of CD8+ T cells.16 Similarly, in patients with gastric cancer, a population of CD11blowCD33lowCD66bhi cells was identified in peripheral blood that suppress CD8+ cell activity.17 ARG1 expression has also been observed in peripheral CCR5+ LDNs from patients with melanoma.