Clinical and Hematological Characteristics of Hepatosplenic T γ/δ Lymphoma with Isochromosome for Long Arm of Chromosome 7

Abstract

Hepatosplenic T gamma/delta lymphoma is a rare entity of peripheral T cell lymphoma. Three of 386 patients with non-Hodgkin's lymphoma in our institute were found to have this subtype of lymphoma. All had chromosomal abnormalities of isochromosome 7q and trisomy 8. The clinical and hematological features of these three patients are reported. All were males with ages ranging from 23 to 29 years. Initial presentation comprised purpura and variable degree of hepatosplenomegaly. None had superficial lymphadenopathy. Hematologically, they showed pictures resembling immune related thrombocytopenia and/or hemolytic anemia. Examination of the bone marrows revealed hypercellularity with increased number of megakaryocytes and erythroid cells and various degrees of abnormal lymphoid cell infiltration. The histopathologic section of the spleen from one patient who underwent splenectomy revealed abnormal cell infiltration in the sinusoids of the red pulp. Lymphoma cells showed T gamma/delta lymphoid immunophenotype (CD3+ CD2+ CD4- CD8-, TCR delta-1+, and beta F1-). The platelet counts were elevated transiently after initial treatment with corticosteroids, but the condition soon deteriorated. All died of refractory lymphoma five to nine months after diagnosis. Review of the literature, showed that only four other cases have been reported until now and although no cytogenetic data were available for these patients, they had very similar clinical pictures as those in this series. It is suggested that hepatosplenic T gamma/delta lymphoma represents a rare, but distinct, clinicopathological and cytogenetic entity.

Hepatosplenic T-cell lymphoma is a rare clinicopathologic entity with poor outcome: report on a series of 21 patients

“…Therefore, in the context of antigen-driven stimulation of reactive ␥␦ T cells, it is tempting to speculate that neoplastic transformation could result from a multistep process involving impairment of the immune system (as in the patients receiving immunosuppressive therapy) or additional genetic alterations such as isochromosome arm 7q. The latter aberration was present in 9 of 13 documented cases, further confirming the association between HS␥␦TCL and isochromosome arm 7q, which was reported as a hallmark not only of HS␥␦TCL 12,14,25,[28][29][30][31][32] but also of its unusual ␣␤ immunophenotypic variant. 33,35 Although the mechanism by which it might contribute to the pathogenesis of HSTCL is unknown, its previously reported accumulation in forms with features of cytologic progression suggests that it benefits the outgrowth of malignant clones.…”

“…The identification of this lymphoma subtype, recognized as a provisional entity in the Revised European American Lymphoma (REAL) classification, 26 has been further supported by its cytotoxic phenotype 11,27 and its strong association with the isochromosome arm 7q cytogenetic abnormality. 12,14,25,[28][29][30][31][32] More recently, a few cases of HSTCL with sinusoidal infiltration and an ␣␤ T-cell receptor phenotype have been reported. [33][34][35] This is now considered an immunophenotypic variant of the same disease entity in the World Health Organization (WHO) classification.…”

Human Calcium Transport Protein CaT1

“…Rearrangements, translocations and other abnormalities in chromosome 7q have been detected in various tumor types and are particularly common in benign and malignant mesothelial tumors, secondary leukemias, testicular cancers and carcinomas of the ovary and prostate (31)(32)(33)(34)(35)(36). Furthermore, cardiovascular abnormalities occur in association with duplicated segments of chromosome 7 (37) or with terminal deletion of 7q (38).…”

“…The human CaT1 cDNA was obtained through a combination of low stringency screening, using 32 P-labeled rat CaT1 cDNA as a probe to screen a human small intestinal cDNA library (Clontech Laboratories, Inc., Palo Alto, CA) (1), and PCR amplification, using Marathon ready cDNA (Clontech). The resulting human CaT1 cDNA was sequenced bidirectionally.…”

Hepatosplenic T cell lymphoma. A review on 45 cases since the first report describing the disease as a distinct lymphoma entity in 1990

“…Earlier studies showed the presence of an isochromosome 7q, often associated with trisomy 8, 9,[13][14][15] inspiring the discussion that isochromosome 7q may represent the primary chromosomal aberration accompanied by trisomy 8 as a secondary change. 9 Meanwhile isochromosome 7q has been detected in 13 of the patients, all of them male, and associated with trisomy 8 in 10 cases, however, trisomy 8 without isochromosome 7 has not been reported (Table 4).…”