Interim PET predicted outcome in the entire population and in all subgroups except anaplastic lymphoma kinase (ALK)-positive anaplastic large-cell lymphoma (ALCL; negative predictive value for relapse in the entire population, 75.7%; positive predictive value, 52.8%; and diffuse large B-cell lymphoma [DLBCL] subgroup, negative predictive value of 77.1% and positive predictive value of 46.9%; Figure 2). Here, ALK is linked to anaplastic large cell lymphoma.