Brentuximab vedotin is therefore indicated in Europe for the treatment of patients with CD30-positive CTCL who have received prior systemic therapy and in the USA for patients with C-ALCL and CD30-positive MF who have received prior systemic therapy [6, 7] (although the exact cut-off point for determination of CD30-positivity for most CTCL is still a matter of debate [3]). This evidence concerns the gene TNFRSF8 and mycosis fungoides.