Adult T‐cell leukaemia/lymphoma

摘要

Adult T‐cell leukaemia/lymphoma (ATLL) is a mature T‐cell neoplasm of post‐thymic lymphocytes aetiologically linked to the human T‐cell lymphotropic virus, HTLV‐I, and with a distinct geographical distribution. The disease manifests with leukaemia in greater than two thirds of patients, while the remaining patients have a lymphomatous form. According to the disease manifestations, various forms which differ in clinical course and prognosis have been recognised: acute, chronic, smouldering and lymphoma. Organomegaly, skin involvement, circulating atypical lymphocytes (“flower” cells) with a CD4+ CD25+ phenotype and hypercalcaemia are the most common disease features. The diagnosis should be based on a constellation of clinical features and laboratory investigations. The latter comprise: lymphocyte morphology, immunophenotype, histology of the tissues affected in the pure lymphoma forms and serology or DNA analysis for HTLV‐I. The differential diagnosis of ATLL includes other mature T‐cell neoplasms such as T‐cell prolymphocytic leukaemia (T‐PLL), Sézary syndrome (SS), peripheral T‐cell lymphomas and occasionally healthy carriers of the virus or Hodgkin disease. The clinical course is aggressive with a median survival of less than 12 months in the acute and lymphoma forms. Despite major advances in understanding the pathogenesis of the disease, management of these patients remains a challenge for clinicians as they do not respond or achieve only transient responses to therapies used in high‐grade lymphomas. The use of antiretroviral agents such as zidovudine in combination with interferon‐alpha, with or without concomitant chemotherapy, has shown activity in this disease with improvement in survival and response rate. Consolidation with high dose therapy and autologous or allogeneic stem‐cell transplantation should be considered in young patients.