T-cell lymphoma with large multilobated nuclei

Orchestral role of lipid metabolic reprogramming in T-cell malignancy

The immune function of normal T cells partially depends on the maneuvering of lipid metabolism through various stages and subsets. Interestingly, T-cell malignancies also reprogram their lipid metabolism to fulfill bioenergetic demand for rapid division. The rewiring of lipid metabolism in T-cell malignancies not only provides survival benefits but also contributes to their stemness, invasion, metastasis, and angiogenesis. Owing to distinctive lipid metabolic programming in T-cell cancer, quantitative, qualitative, and spatial enrichment of specific lipid molecules occur. The formation of lipid rafts rich in cholesterol confers physical strength and sustains survival signals. The accumulation of lipids through de novo synthesis and uptake of free lipids contribute to the bioenergetic reserve required for robust demand during migration and metastasis. Lipid storage in cells leads to the formation of specialized structures known as lipid droplets. The inimitable changes in fatty acid synthesis (FAS) and fatty acid oxidation (FAO) are in dynamic balance in T-cell malignancies. FAO fuels the molecular pumps causing chemoresistance, while FAS offers structural and signaling lipids for rapid division. Lipid metabolism in T-cell cancer provides molecules having immunosuppressive abilities. Moreover, the distinctive composition of membrane lipids has implications for immune evasion by malignant cells of T-cell origin. Lipid droplets and lipid rafts are contributors to maintaining hallmarks of cancer in malignancies of T cells. In preclinical settings, molecular targeting of lipid metabolism in T-cell cancer potentiates the antitumor immunity and chemotherapeutic response. Thus, the direct and adjunct benefit of lipid metabolic targeting is expected to improve the clinical management of T-cell malignancies.

B-cell lymphoma of large multilobated type: an immunohistochemical study of 8 cases and review of the literature

Large multilobated cell lymphomas represent an heterogenous group comprising both B-cell and T-cell subtypes. The correct lineage identification of each subtype cannot be based on morphologic grounds, as it has already been stressed by other authors, and demands the use of immunophenotyping methods. In this study we review the literature and present eight new cases of large multilobated B-cell lymphoma which have been immunophenotyped in paraffin sections with a panel of monoclonal [L26 (CD20), 4KB5 (CD45R), UCHL1 (CD45RO), MT1 (CD43)] and polyclonal (anti-CD3, anti-kappa, anti-lambda) antibodies. We further investigated the expression of c-myc p62 oncoprotein and of proliferating cell nuclear antigen (PCNA) using the monoclonal antibodies c-myc 1-9E10 and PC-10 respectively. In all cases the neoplastic cells were positive for L26 (CD20) and negative for anti-CD3. Five cases were positive for 4KB5 (CD45R) while six cases stained positively for UCHL1 (CD45RO) or MT1 (CD43). Four cases were monoclonal in respect to light chain restriction. Immunoreactivity with c-myc 1-9E10 and PC-10 was observed in all cases. As far as c-myc 1-9E10 is concerned, positive cells constituted more than 45% of the neoplastic population in six cases, whereas in all cases the percentage of PC-10 positive cells was greater than 45%. The staining pattern was nuclear and/or cytoplasmic for c-myc 1-9E10 but solely nuclear for PC-10. The elevated c-myc and PCNA expression are indices of high proliferation rate in this type of lymphoma and may suggest a high malignancy grade.

Primary gastric peripheral T-cell malignant lymphoma with helper/inducer phenotype. First case report with a complete histological ultrastructural and immunochemical study

Primary gastrointestinal T-cell malignant lymphomas (T-ML) are very rare. In this case report we describe a primary gastric tumor with local lymph node involvement. On the basis of histologic, immunohistochemical, and electron microscopic studies, the authors classified this tumor as a pleomorphic T-ML, large cell variant with peripheral helper/inducer T-cell phenotype (Leu1/CD5+, Leu4/CD3+, Leu5/CD2+, Leu9/CD7+, and Leu3/CD4+). The extreme pleomorphism of lymphoma cells, the numerous giant cells, and the presence of tumor nodules with two or three concentric layers were the three striking morphologic features of our case. Tumor cells showed an inconstant but true positive staining with anti-LeuM1/CD15 and LeuM3/CD14 antibodies. Vimentin positivity could be related to the presence of intermediate filaments at ultrastructural level. Neuron-specific enolase reactivity was a peculiar but unexplained feature. Furthermore, the positivity of the surface markers Ki-1/CD30, anti-Tac/CD25 and HLA-DR, and the nuclear marker Ki-67 suggested an activation state and a high proliferative activity of the tumor cells. This study emphasizes the usefulness of combined pathologic methods in order to rule other diagnoses such as undifferentiated carcinoma, malignant melanoma, malignant histiocytosis, B-cell lymphoma and interdigitating reticulum cells sarcoma, in view of an extremely polymorph tumor proliferation. This is apparently the first completely documented case report of a primary gastric pleomorphic T-ML of peripheral T-cell origin.

Multilobated non-Hodgkin's lymphoma. A clinicopathologic entity

Multilobated non-Hodgkin's lymphomas (NHL) have recently been recognized as an NHL variant. During a period of 10 years we observed 30 individuals with NHL in which more than 30% of the malignant cells had a characteristic multilobation. The immunologic phenotype was determined in 14 of these cases. One was of T-cell lineage, and the others exhibited B-lymphoid markers. Sixty-eight percent of the patients presented with extranodal localizations. In the clinical follow-up a complete remission was observed in 78% of patients with a mean duration of 37 months (range, 5 to 120 months). The actuarial survival after 5 years was 45%. From these data we conclude that multilobated NHL are comparable to diffuse, large cleaved-cell NHL of an intermediate grade malignancy according to the Working Formulation or are comparable to the diffuse centrocytic-centroblastic NHL according to the Kiel classification. The neoplastic cells are to be considered as variants of follicle center cells, but the clinicopathologic correlation indicates that multilobated NHL represent a distinct nosologic entity.