CTLA4 and melanoma: However, in other studies textural parameters do carry prognostic information: in 34 patients with melanoma (stage from I to IV) treated with various immunotherapies (anti-PD1 and anti-CTLA4) as first or other line of treatment, gradient based tumour heterogeneity on pre-treatment 18F-FDG PET correlated to survival outcome, as well as SUVmax and TLG.