Knorr F, et al. - Given the titer of anaplastic lymphoma kinase (ALK) autoantibodies in patients with nucleophosmin (NPM)-ALK-positive anaplastic large cell lymphoma (ALCL) is inversely associated with the risk of relapse, researchers tested the presumption that the epitopes recognized by these autoantibodies in NPM-ALK may be related to different ALK-antibody levels. They found that antibodies found in sera from ALCL patients bound to epitopes mostly in the C-terminal region of the ALK portion of NPM-ALK (amino acid positions 469–496, 561–588, 617–644). They also found that patients with higher ALK antibody titers vs patients with intermediate and low titers detected the epitope 561–588 more frequently, as well as three further epitopes at the N-terminus of the kinase domain. This study provides new potential target epitopes for immunotherapy in ALK-positive ALCL. The methodology can be adapted for more reproducible analyses of tumor antigen detection.