T-Cell Lymphoblastic Lymphoma Arising in the Setting of Myeloid/Lymphoid Neoplasms with Eosinophilia: LMO2 Immunohistochemistry as a Potentially Useful Diagnostic Marker

Abstract

Background: Rarely, T-lymphoblastic lymphoma (T-LBL) may develop in the setting of myeloid/lymphoid neoplasms with eosinophilia (M/LNs-Eo), a group of diseases with gene fusion resulting in overexpression of an aberrant tyrosine kinase or cytokine receptor. The correct identification of this category has relevant therapeutic implications. LIM domain only 2 (LMO2) is overexpressed in most T-LBL, but not in immature TdT-positive T-cells in the thymus and in indolent T-lymphoblastic proliferations (iT-LBP). Methods and Results: We retrospectively evaluated 11 cases of T-LBL occurring in the context of M/LNs-Eo. Clinical, histological, immunohistochemical and molecular features were collected and LMO2 immunohistochemical staining was performed. The critical re-evaluation of these cases confirmed the diagnosis of T-LBL with morphological, immunohistochemical and molecular features consistent with T-LBL occurring in M/LNs-Eo. Interestingly, LMO2 immunohistochemical analysis was negative in 9/11 cases, whereas only 2 cases revealed a partial LMO2 expression with a moderate and low degree of intensity, respectively. Conclusions: LMO2 may represent a potentially useful marker to identify T-LBL developing in the context of M/LNs-Eo. In this setting, T-LBL shows LMO2 immunohistochemical profile overlapping with cortical thymocytes and iT-LBP, possibly reflecting different molecular patterns involved in the pathogenesis of T-LBL arising in the setting of M/LNs-Eo.

FIP1L1‐PDGFRA fusion gene in T‐lymphoblastic lymphoma: A case report

“…T‐LBL is a rare and aggressive form of precursor T‐cell non‐Hodgkin's Lymphomas (T‐NHLs) affecting mainly children and young adults and involving lymph nodes, BM and thymus. 1 T‐LBL represents around 85% of all immature lymphoblastic lymphomas, whereas immature B‐cell.…”

“…T‐lymphoblastic lymphoma (T‐LBL) is an aggressive malignancy of T‐lymphoid precursors, which can rarely co‐occur with Myeloid/Lymphoid Neoplasms with Eosinophilia (M/LNs‐Eo). 1 Acquired genetic and epigenetic aberrations affect the early thymocyte subset leading to the formation of T‐LBL and T‐ALL malignancies. T‐ALL and T‐LBL are commonly found amongst children and young adults, manifesting in 15% of the ALL cases, whereas T‐LBL affects 20% of the non‐Hodgkin lymphomas (NHLs).…”

“…T‐lymphoblastic lymphoma (T‐LBL) is an aggressive malignancy of T‐lymphoid precursors, which can rarely co‐occur with Myeloid/Lymphoid Neoplasms with Eosinophilia (M/LNs‐Eo) 1 . Acquired genetic and epigenetic aberrations affect the early thymocyte subset leading to the formation of T‐LBL and T‐ALL malignancies.…”

Diagnosing Lymphoma on Core Needle Biopsy and the Challenging Role of Immunohistochemistry

“…LMO2 is highly expressed in the majority of T-LBLs, whereas it is not observed in undeveloped TdT-positive T cells in the thymus or slow-growing T-lymphoblastic growths. Out of 11 cases of T-LBLs linked to myeloid/lymphoid neoplasms with eosinophilia, a study found that nine of them did not have LMO2, indicating a distinct molecular process for T-LBLs associated with myeloid/lymphoid neoplasms with eosinophilia [ 25 ]. Interestingly, LMO2 expression is observed in lymphomas derived from germinal center lymphocytes, including FL, Burkitt lymphoma (BL), and DLBCL, as well as in NLPHL [ 18 ].…”

PET/CT Evaluation of the Effect of Allogeneic Hematopoietic Stem Cell Transplantation in the Treatment of T‐Cell Lymphoblastic Lymphoma

“…At present, T-cell lymphoblastic lymphoma and T-cell acute lymphocytic leukemia (T-ALL) are defined as the same type of disease in clinical practice [4,5]. T-cell lymphoblastic lymphoma is a rare and highly aggressive Hodgkin's lymphoma in clinical practice, which is common in children and adolescents, especially in male children and adolescents [6,7]. At present, the treatment for T-cell lymphoblastic lymphoma in clinical practice is mainly high-dose chemotherapy (HDC) combined with a variety of drugs [8][9][10].…”