T‐Cell Lymphoproliferative Disorders

Abstract

Major advances in the characterization and classification of the T-lymphoproliferative disorders have been made over the last decade. This has been possible by a more careful examination of cell morphology and histology compounded with the progress on immunologic and molecular methods and their application to the study of leukemias and lymphomas. The availability of markers which detect specific T-cell antigens and proteins encoded by certain oncogenes, together with the use of sensitive molecular techniques, has made a major impact in the characterization of the various T-cell diseases. This has resulted in the identification of distinct entities and made it possible to devise novel and effective therapies, as well as providing some clues to the pathogenesis of these disorders. The mature/chronic T-cell disorders are classified on the basis of the clinical presentation in primary leukemias, T-cell lymphomas and leukemia/lymphoma syndromes or the leukemic phase of T-cell lymphoma. Each of these groups includes a variety of disease entities, which are defined by their clinical characteristics, and a constellation of laboratory features that include histomorphology, immunophenotype and molecular genetics. Although primary and secondary pathogenic events have been established in certain T-cell malignancies, further studies are needed to disclose new disease entities.

T Cell Prolymphocytic Leukemia (T-PLL): Cutaneous Involvement in an Uncommon Leukemia

“…The resultant TCL1 gene is strongly expressed and can be detected by immunohistochemistry. An association with Ataxia-Telengiectasia has also been reported [2,4].…”

“…The median age at presentation is 65 years. Lymphadenopathy and hepatosplenomegaly are common with skin lesions and effusions seen in 20 and 15% of patients respectively [1,2].…”

“…Patients have leukocytosis with one thirds having associated anemia and thrombocytopenia. Liver function tests are frequently abnormal with raised urate and lactate dehydrogenase levels [2]. Peripheral blood smear shows prolymphocytes with classical T-PLL seen in two-thirds of patients with larger lymphoid cells with irregular outline and cytoplasmic blebs.…”

“…Peripheral blood smear shows prolymphocytes with classical T-PLL seen in two-thirds of patients with larger lymphoid cells with irregular outline and cytoplasmic blebs. Remaining patients show small lymphoid cells or have cerebriform nuclei [2][3][4]. Skin lesions are often seen without epidermotropism [5].…”

Prolymphocytic leukaemia of B‐ and T‐cell subtype: a state‐of‐the‐art paper

“…Mutations in any of the TCR subunits lead to T‐lymphoproliferative diseases derived from post‐thymic immunocompetent lymphoid cells such as in T‐PLL (26). There is no evidence that radiation, carcinogenic agents or viruses play a role in the pathogenesis of T‐PLL (27). In adults T‐PLL arises sporadically and there is a close relationship between the sporadic form of T‐PLL and the leukaemia that occurs in patients with the inherited disorder ataxia telengectasia (AT) (28).…”