In the future, PET status before ASCT should be assessed to allow for the identification of high-risk patients in combination with other established risk factors and to conduct risk-adapted therapy where appropriate. Owing to a lack of prospective data from uniformly treated patients, PET is not yet fully established for response assessment of HL patients before and after ASCT. Furthermore, the ideal therapy for patients with positive PET before ASCT has not yet been defined. Second-line, noncross-resistant salvage chemotherapy and/or tandem transplant seem to be reasonable alternatives. Additionally, new drugs such as brentuximab vedotin may be used after first-line salvage failure to achieve remission and allow for potentially curative ASCT, but this approach has yet not been assessed in clinical trials. Moreover, maintenance therapy for high-risk HL patients who achieve CR after ASCT is currently being evaluated in two large randomized clinical trials. Positive PET is not included in the high-risk definition in both trials. If maintenance proves to be effective for those 'conventional' high-risk patients, it might also be evaluated in patients with positive PET before or after ASCT. Finally, allogeneic transplant only has a very limited role in HL owing to insufficient responses and high treatment-related morbidity and mortality. However, PET before transplant in combination with other risk factors might identify patients that have a poor chance of being cured with ASCT. Those patients might be candidates for an early allogeneic transplant. Prospective, randomized trials further characterizing the prognostic role of PET and comparing different approaches for PET-positive patients in the ASCT setting will hopefully answer these questions in the next few years.
Papers of special note have been highlighted as:
Expert Rev Hematol. 2012;5(5):483-486. © 2012 Expert Reviews Ltd.