Immunophenotyping of mature T/NK cell neoplasm presenting as leukemia.

Introduction : Mature T/NK cell lymphomas (MTNKL) presenting as leukemia are rare and show considerable overlapping of clinical, morphological and immunophenotypic features. AIM: Critical analysis of the morphology and immunophenotypic profile of MTNKL. Materials and Methods : We reviewed 380 consecutive cases of mature lymphoid neoplasm that presented as leukemia and were diagnosed on morphology and immunophenotyping of bone marrow and/or peripheral blood samples. Results : Peripheral blood and bone marrow involvement was seen in all cases. MTNKL constituted 4% (nine cases) of all mature lymphoid neoplasms presenting as leukemia. It included four cases of T-large granular leukemia (T-LGL), two of T-cell prolymphocytic leukemia small cell variant (T-PLL), two of adult T-cell leukemia/lymphoma (ATLL) and one of primary cutaneous gamma delta T-cell lymphoma (PCGDTCL). T-LGL revealed CD4-/CD8+ phenotype in three, and CD4+/CD8+ phenotype in one case. CD56 was absent in all the cases of T-LGL. One case of T- PLL small cell variant showed CD4+/CD8- phenotype, while the other revealed CD4-/CD8+ phenotype. Both cases of ATLL showed CD4+/CD8+/CD25+ phenotype. The single case of PCGDTCL showed CD4-/CD8- phenotype pattern. CD3 and CD5 were expressed in all MTNKL. CD7 was absent in three cases of T-LGL. TCRα/β was performed in three cases of T-LGL and was positive in all. TCRα/β was also seen in both the cases of T-PLL small variant. However, TCRα/β was seen in the single case of PCGDTCL. Conclusion : Mature nodal T/NK cell neoplasms are rare and MTNKL presenting as leukemia are even rarer. There is an overlap between the immunophenotypic profiles of different MTNKL subtypes and elaborate T/NK cell panels are required for their evaluation.

Proteína Tax ( HTLV-I ), probable factor patogénico y marcador del síndrome sicca que se asocia a HAM/TSP / Viral Tax protein expression in salivary glands of patients infected with human t-cell lymphotropic virus type I and Sicca Syndrome

Background: Human T-cell lymphotropic virus type I (HTLV-I) is a retrovirus that influences cellular metabolism modifying biological responses. This results in oncogenic, degenerative or inflammatory changes. The myelopathy associated to HTLV-I or tropical spastic paraparesia (HAM/TSP) is a mainly degenerative response to the virus infection. On the other hand, Sjögren syndrome has an inflammatory appearance. The immunohistochemical study of CD-4, CD-8 and CD45 lymphocytes, metalloproteinase MMP-9 and viral Tax protein in pathological samples of salivary glands may help to differentiate primary from viral Sicca syndrome. Aim: To perform an immunohistochemical study of salivary glands of patients with HAM/TSP and Sicca syndrome and control subjects. Material and Methods: Pathological samples of salivary glands from 53 patients with HAM/TSP and Sicca syndrome and 10 control subjects, were studied. Immunohistochemistry was performed using antibodies against CD-4, CD-8 and CD-45 lymphocytes, metalloproteinase MMP-9 and viral Tax protein. Results: Only in patients with HAM/TSP and Sicca syndrome, the presence of Tax protein was observed in CD-4 and CD-8 lymphocytes and in glandular acini. Conclusions: Patients infected with HTLV-I express Tax protein in salivary glands. This finding has diagnostic and pathogenic implications.

Leucemia linfoma T del adulto en Chile: estudio clínico patológico y molecular de 26 pacientes / Adult T cell leukemia lymphoma in Chile: a clinical-pathological and molecular study of 26 patients

Background: Adult T cell leukemia lymphoma is a lymphoproliferative syndrome etiologically associated to human T cell lymphotropic virus type I. Aim: To describe the clinical and laboratory features of 26 caucasian chilean patients, with HTLV-I positive adult T-cell leukemia lymphoma (ATLL). Material and methods: Diagnostic criteria included clinical features, cell morphology, immunophenotype, HTLV-I serology and/or DNA analysis by southern blot or PCR. Results: According to the clinical presentation, 12 cases had the acute ATLL form, 6 had a lymphoma, 4 the chronic form and 4 had smoldering ATLL. The median presentation age was 50 years, younger than the Japanese patients, but significantly older than patients from other south american countries (eg Brasil, Jamaica, Colombia). The main clinical features: lymphadenopathy, skin lesions and hepatosplenomegaly, were similar in frequency to those of patients from other countries, except for the high incidence of associated neurological disease. Tropical spastic paraparesis (TSP) in our series of ATLL, was seen in one third of the patients (8/26). A T-cell immunophenotype was shown in all 26 cases and HTLV-I serology was positive in 25/26 patients. Molecular analysis on the seronegative patient showed clonal integration of proviral HTLV-I DNA into the lymphocytes DNA, and thus he may have been a poor responder to the retroviral infection. Proviral DNA integration was also demonstrated in 15/16 patients being clonal in 10, polyclonal in 3 (all smoldering cases) and oligoclonal in one. Conclusions: ATLL in Chile has similar clinical and laboratory features than the disease in other parts of the world, except for a younger age than japanese patients but older than those from other latin american countries and a high incidence of patients with associated TSP. Detailed morphological and immunophenotypic analysis of the abnormal circulating lymphocytes, together with the documentation of HTLV-I by serology and/or DNA analysis are key tests for the identification of this disease

Immunophenotyping of acute lymphoblastic leukemia in pediatric patients by three-color flow cytometric analysis.

Immunophenotyping of acute lymphoblastic leukemia (ALL) in children using three-color flow cytometry was carried out at Chulalongkorn Hospital, Bangkok, Thailand. Of 38 patients with acute lymphoblastic leukemia, 65.8% were identified as common ALL, 15.8% were B-ALL, and 18.4% were T-ALL. Of these 38 cases, there were 4 cases of infantile leukemia. Relapsed cases of leukemia were found most in B-ALL up to 3 out of 6 cases and to a lesser extent in T-ALL (1 of 7 cases) and c-ALL (1 of 25 cases). Our data showed the CD markers expression for common ALL (c-ALL) were CD19+/10+ (100%), CD20+ (24%), CD22+ (100%), HLA-DR+ (70.1%), and CD34+ (58.8%). CD markers expression for B-ALL were CD19+ (100%), CD20+ (33.3%), CD22+ (80%), and HLA-DR+ (80%). CD markers expression for T-ALL were CD3+ (42.9%), CD5+ (100%), CD7+ (85.7%). Myeloid aberrant expressions were found in c-ALL (25-37.5%), B-ALL (20%), and T-ALL (14.3%). The significance of the aberration is discussed. The immunophenotyping classification of ALL as c-ALL, B-ALL, and T-ALL is useful in prognosis and treatment.

Mecanismos de ativaçäo do linfócito T e induçäo da leucemia linfoma T do adulto pelo HTLV I / Lymphocyte T activation and adult T lymphoma-leukemia induction by HTLV I

A infecçäo pelo vírus linfotrópico de célula T, tipo I (HTLV I), endêmica em algumas regiöes do mundo, ganha conotaçäo principalmente pelo fato de induzir a leucemia linfoma T do adulto e paraparesia espástica tropical/mielopatia associada ao HTLV I. O conhecimento da fisiopatologia da transformaçäo da célula T auxilia tanto a compreensäo das vias normais de ativaçäo/proliferaçäo do linfócito, como no mecanismo de aparecimento de doenças linfoproliferativas. As estratégias usadas pelo vírus para induzir à proliferaçäo celular afeta o ciclo celular em diferentes estágios e em diferentes vias de sinalizaçäo. Seräo analisadas as principais vias envolvidas nessa questäo e alguns mecanismos de açäo do vírus.

HTLV-I associated cutaneous T-cell lymphoma: report of a case with atypical clinical presentation

A case of a 20-years-old black man from Salvador, Bahia with HTLV-I associated T cell lymphoma is presented. In spite of the absence of splenomegaly and leukemia, the patient had a marked cephalic tumoral infiltrationassociated with axillary tumors in a pattern not yet described in adult T cell lymphoma. Peripheral blood involvement was observed later on in the course of thedisease. The patient underwent chemotherapy but died seven monts after diagnosis

Effects of IL-7 on human lymphocytes

Interleukin-7 (IL-7) is known as a growth factor for pre B-cell and mature T-cells in human. But in leukemic cells, IL-7 effect is variously reported. To investigate the effect of IL-7 on the cells of childhood acute leukemia we used 3H-Thymidine assay. Twelve Acute lymphoblastic leukemia (ALL), seven T-ALL and three Acute myelogenous leukemia (AML) were involved in this study. Two out of twelve ALL and three out of seven T-ALL bone marrow (BM) cells were stimulated by IL-7 in 3H-Thymidine incorporation. In normal and AML BM cells, IL-7 had no stimulatory activity as in various leukemic cell lines. Two normal peripheral blood T-cells responded to IL-7 dose dependently. We have seen the effect of IL-7 to stimulate T-lineage cells but, for precise conclusion, further study using more purified samples will be needed.

Acute leukemias with unusual immunophenotypes

Over a two-year period, immunophenotypic patterns of 266 acute leukemia cases were analyzed using a panel of tests including TdT, SmIg and 9 surface antigens by the immunofluorescence stains for the assessment of the incidence and grade of phenotypic ambiguity (lineage infidelity) and the possible clinical significance of unusual immunophenotypes. Immunophenotypes were classified into four groups according to the degree of ectopic antigen expression. We classified as Group A (91.7%, 244 of 266 cases) those expressing conventional pattern without ectopic antigen. Group B (3.0%, 8 of 266 cases) was defined to have at least two lineage specific markers and single ectopic antigen. Such a "low grade deviation" did not prevent a definite immunodiagnosis. Group C (4.2%, 11 of 266 cases) revealed a promiscuous coexpression of markers related to different lineages, including two cases (0.8%, 2 cases) of biphenotypic leukemia. Group D (1.1%, 3 cases) included unclassifiable immunophenotypes with no antigen or HLA-DR only expression. Both patients with biphenotypic leukemia and one patient with unclassifiable immunophenotypes failed to respond to induction chemotherapy, suggesting a poor prognosis in these patients. The incidence of acute myelogenous leukemia (AML) cases with one or more ectopic surface antigens was 10 (8.1%) of the 124 AML cases. Ectopic antigen expression was seen in 5 (4%) of the 125 B-lineage acute lymphoblastic leukemia (ALL) cases and 3 (25%) of the 12 T-ALL cases. It is concluded that nearly 95% of cases of acute leukemia cases can be diagnosed accurately with immunophenotyping alone including patients with a mild degree of deviation from expected antigenic patterns.(ABSTRACT TRUNCATED AT 250 WORDS)