Lymphoma and Chronic Lymphocytic Leukemias

T-cell lymphomas represent 10–12% of all patients with non-Hodgkin lymphoma (NHL) in the Western world. When cutaneous T-cell lymphoma (CTCL) is excluded, peripheral T-cell lymphoma—not otherwise specified (PTCL-NOS), anaplastic large-cell lymphoma (ALCL), and angioimmunoblastic T-cell lymphoma (AITL) represent the overwhelming majority of patients in this population. These diseases remain a great challenge to treat. They are characterized by an aggressive presentation, extranodal disease, paraneoplastic phenomena, and resistance to standard chemotherapeutics. With the rapid development of new molecular gene profiling techniques, it is highly likely that these diseases will be subclassified by molecular abnormalities in the future. An evolving understanding of the tumor molecular pathogenesis will undoubtedly lead to further novel targeted therapies. Immunoconjugates, such as brentuximab vedotin (BV), have provided outstanding responses in relapsed, refractory CD30-positive ALCL. Histone deacetylase (HDAC) inhibitors have shown activity in PTCL and are potentially synergistic with proteasome inhibitors. Denileukin diftitox is an interesting recombinant DNA fusion protein linking fragments of the diphtheria toxin to interleukin-2 (IL-2) that is tested in clinical trials. Crizotinib, a highly specific anaplastic lymphoma kinase (ALK) inhibitor, has shown great promise in small number of patients with ALK-positive ALCL; the future of patients with this disorder looks very promising. Biomarker-driven chemotherapeutics is becoming a critical part of the state-of-the-art treatment in early- and late-phase clinical trials. It is crucial that future trials include sensible biomarker-based designs when future treatments are used in these challenging disorders.