The aggressive peripheral T-cell lymphomas: 2017

T-cell lymphomas make up approximately 10%-15% of lymphoid malignancies. The frequency of these lymphomas varies geographically, with the highest incidence in parts of Asia.

The diagnosis of aggressive peripheral T-cell lymphoma (PTCL) is usually made using the World Health Organization classification. The ability of hematopathologists to reproducibly diagnose aggressive PTCL is lower than that for aggressive B-cell lymphomas, with a range of 72%-97% for the aggressive PTCLs. Risk Stratification: Patients with aggressive PTCL are staged using the Ann Arbor Classification. Although somewhat controversial, positron emission tomography scans seem to be useful as they are in aggressive B-cell lymphomas. The specific subtype of aggressive PTCL is an important risk factor with the best survival seen in anaplastic large-cell lymphoma-particularly young patients with the anaplastic lymphoma kinase positive subtype.

Anaplastic large-cell lymphoma is the only subgroup to have a good response to a CHOP-like regimen. Angioimmunoblastic T-cell lymphoma has a prolonged disease-free survival in only ∼20% of patients, but younger patients who have an autotransplant in remission seem to do better. PTCL-not otherwise specified is not one disease. Anthracycline-containing regimens have disappointing results, and a new approach is needed. Natural killer/T-cell lymphoma localized to the nose and nasal sinuses seems to be best treated with radiotherapy-containing regimens and the majority of patients are cured. Enteropathy-associated PTCL and hepatosplenic PTCL are rare disorders with a generally poor response to therapy although selected patients with enteropathy- associated PTCL seem to benefit from intensive therapy.