Although less recurrent genetic imbalances such as MYC gain (40%) and MNT loss (30%) together with variable genomic or epigenetic criteria have been proposed to differentiate SS from erythrodermic inflammatory dermatoses [4, 49], our study is original in supporting the introduction of a simple and robust TP53 testing in algorithms for the diagnosis of patients with erythroderma as well as for leukemic assessment in patients with CTCL. Here, MYC is linked to synovial sarcoma.