Likewise, for CTCLs, elevated serum IL-18 and IL-18 mRNA in skin lesions were reported [120], while for the rare NK/T-cell lymphomas, high IL-18 serum levels were associated with advanced-stage disease, the presence of hemophagocytosis, and poor treatment outcomes [128]. The gene discussed is IL18; the disease is extranodal nasal NK/T cell lymphoma.