Paediatric lymphoblastic T‐cell leukaemia and lymphoma: one or two diseases?

Abstract

Summary There is ongoing discussion on whether paediatric acute T‐cell lymphoblastic leukaemia (T‐ALL) and paediatric lymphoblastic T‐cell lymphoma (T‐LBL) are two distinct entities or whether they represent two variant manifestations of one and the same disease and the distinction is arbitrary. Both show overlapping clinical, morphological and immunophenotypic features. Many clinical trials use the amount of blast infiltration of the bone marrow as the sole criterion to distinguish between T‐ALL and T‐LBL. The current World Health Organization classification designates both malignancies as T lymphoblastic leukaemia/lymphoma. However, subtle immunophenotypic, molecular and cytogenetic differences suggest that T‐ALL and T‐LBL might be biologically different in certain aspects. The current review summarizes and discusses the recent advances and understanding of the molecular profile of paediatric T‐ALL and T‐LBL.

Phenotype diversity in type 1 Gaucher disease: discovering the genetic basis of Gaucher disease/hematologic malignancy phenotype by individual genome analysis

“…The malignant clones in patients with T-LBL and T-cell lymphoblastic leukemia are thought to originate from normal lymphoid progenitor cells arrested at the early stages of T-cell maturation. 41,42 Recent demonstration of impaired T-cell maturation in a mouse model of GD suggests that GD patients might be especially vulnerable to T-cell neoplasms, by tipping the delicate balance between normal differentiation and malignant transformation. 18 The thymus is a site for Gaucher cell accumulation, highlighting the need to study the effects of lipid (glucocerebroside, glucosylsphingosine, and secondary metabolites such as ceramide and sphingosine) accumulation in GD on cell differentiation and proliferation.…”

Outcome of children and adolescents with lymphoblastic lymphoma

“…Molecular and cellular pathogenesis of malignant transformation to LBL is still a challenge to be tackled in order to develop strategies for prevention, early identification, and targeted therapies. 4,[6][7][8][9][10][11][12][13]8). LL de células T foi identificado em 16 pacientes (59%) e a manifestação primária mais comum foi o acometimento mediastinal em 9 pacientes (56%).…”

“…10,11 Whether LBL and ALL in childhood are biologically identical or rather distinct disorders is not entirely clear. 12,13 To date, the pathogenesis and genetic changes of LBL is poorly understood. 3 LBLs are most effectively treated using ALL-based therapies.…”

T-Cell Lymphoblastic Lymphoma in a Child Presenting as Rapid Thyroid Enlargement

“…The primary site of disease and the degree of bone marrow involvement distinguish these two disease entities clinically. Even the subtle molecular and cytogenic differences indicate that T-LBL and T-ALL do not share an immunophenotypic and oncogenic profile; T-LBL is an aggressive NHL and frequently invades the central nerve system (CNS); therefore, the treatment for T-LBL should include intensified chemotherapy as is the case for treatment of T-ALL [9, 10]. …”