Clinical, hematologic, and pathologic features of leukemic T-cell lymphoma

Pathogenesis of Metastatic Calcification and Acute Pancreatitis in Adult T-Cell Leukemia under Hypercalcemic State

Human T-cell leukemia virus type-1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL). Hypercalcemia is common in patients with ATL. These patients rarely develop metastatic calcification and acute pancreatitis. The underlying pathogenesis of this condition is osteoclast hyperactivity with associated overproduction of parathyroid hormone-related protein, which results in hypercalcemia in association with bone demineralization. The discovery of the osteoclast differentiation factor receptor activator of nuclear factor-κB ligand (RANKL), its receptor RANK, and its decoy receptor osteoprotegerin (OPG), enhanced our understanding of the mechanisms of ATL-associated hypercalcemia. Macrophage inflammatory protein-1-α, tumor necrosis factor-α, interleukin-1, and interleukin-6 are important molecules that enhance the migration and differentiation of osteoclasts and the associated enhanced production of RANKL for osteoblast formation. In this paper, we focus on metastatic calcification and acute pancreatitis in ATL, highlighting recent advances in the understanding of the molecular role of the RANKL/RANK/OPG system including its interaction with various cytokines and calciotropic hormones in the regulation of osteoclastogenesis for bone resorption in hypercalcemic ATL patients.

Role of tumor suppressor genes in the development of adult T cell leukemia/lymphoma (ATLL)

Adult T cell leukemia/lymphoma (ATLL) is one of the peripheral T cell malignant neoplasms strongly associated with human T cell leukemia virus type-I (HTLV-I). Although the viral transactivating protein Tax has been proposed to play a critical role in leukemogeneis as shown by its transforming activity in various experimental systems, additional cellular events are required for the development of ATLL. One of the genetic events in ATLL is inactivation of tumor suppressor genes. Among many candidates for tumor suppressor genes, the main genetic events have been reported to center around the cyclin-dependent kinase inhibitors ((CDKIs) p15INK4A, p16INK4B, p18INK4C, p19INK4D, p21WAF1, p27KIP1, and p57KIP2), p53 and Rb genes; all of them play a major regulatory role during G1 to S transition in the cell cycle. Acute/lymphomatous ATLL has frequent alterations of p15 (20%) and p16 (28-67%), while chronic/smoldering ATLL has fewer abnormalities of p15 (0-13%) and p16 (5-26%). Most of these changes are deletion of the genes; fewer samples have mutations. ATLL patients with deleted p15 and/or p16 genes have significantly shorter survival than those individuals with both genes preserved. Although genetic alterations of p18, p19, p21, p27 have rarely been reported, inactivation of these genes may contribute to the development of ATLL because low expression levels of these genes seem to mark ATLL. The p53 gene is mutated in 10-50% of acute/lymphomatous ATLL. Functional impairment of the p53 protein, even if the gene has wild-type sequences, has been suggested in HTLV-I infected cells. Each of these genetic events are mainly found in acute/lymphomatous ATLL, suggesting that alterations of these genes may be associated with transformation to an aggressive phenotype. The Rb tumor suppressor gene is infrequently structurally altered, but one half of ATLL cases have lost expression of this key protein. Notably, alterations of one of the CDKIs, p53 and Rb genes appear to obviate the need for inactivation of other genes in the same pathway. A novel tumor suppressor gene on chromosome 6q may also have a critical role in the pathogenesis of ATLL. Taken together, tumor suppressor genes are frequently altered in acute/lymphomatous ATLL and their alteration is probably the driving force fueling the transition from chronic/smoldering to acute/lymphomatous ATLL.

Genetic mutation and early onset of T-cell leukemia in pediatric patients infected at birth with HTLV-I

T-cell leukemia/lymphoma (T-c LL) associated with prior infection with HTLV-I is rarely described in children. We present herein, the clinical, morphological, and virologic features of T-c LL, which occurred in eight pediatric cases with similar features of ATLL described in adults. There were three girls and five boys with age ranging from 2 to 18 years. Lymphoadenopathy, hepatosplenomegaly and marked skin lesions were presented in all cases. Five patients had hypercalcemia. The diagnostic criteria of T-c LL were based on both morphological and immunophenotypical analyses characterized by T-cell markers positively. Seven cases were cCD3+, CD4/CD25+, whereas CD1a and TdT were negative in all cases tested. HTLV-I antibodies were detected in all cases. HTLV-I provirus integration of at least one provirus was seen in all cases tested by molecular analysis. Mother-to-child transmission of HTLV-I was demonstrated in six cases. Interestingly, a homozygous deletion in p16 gene locus was observed in all four cases studied, while exons 7 and 8 of p53 were deleted in one child. The deletion of the p16(INK4A)/p14(ARF) or mutation of p53, key regulatory protein of cell cycle checkpoint in G1/S progression, found in five of the eight pediatric patients suggests that in these cases genetic lesions associated with HTLV-I infection may predispose for an early onset of leukemia.

Canine T-cell lymphomas: a morphological, immunological, and clinical study of 46 new cases

The aim of this study is to report 46 new cases of canine T-cell lymphomas among a series of 140 lymphomas studied by immunophenotyping (incidence 32.8%). According to the updated Kiel classification adapted to the canine species, 13 were classified as low-grade and 33 as high-grade lymphomas. Among the low-grade lymphomas, five were small clear-cell lymphomas, three were pleomorphic small-cell lymphomas, and five mycosis fungoides. Among the high-grade cases, there were 11 pleomorphic mixed-, small-, and large-cell lymphomas, 6 pleomorphic large-cell lymphomas, 11 lymphoblastic lymphomas, and 5 unclassifiable high-grade plasmacytoid lymphomas. The cytohistologic features were highly suggestive of a T-cell phenotype on the basis of cell morphology (irregular nuclei and clear cytoplasms) (30/46 cases), a T-cell zone pattern, and the presence of hyperplastic postcapillary venules (22/46 cases). All 46 cases were CD3+ CD79a-, and among 34 cases investigated for CD4 and CD8 expression, 13 were CD4+CD8-, 13 were CD8+CD4-, and 8 were CD4CD8 double positive or double negative. The pleomorphic mixed lymphomas were mainly CD4+CD8- (6/7) and the lymphoblastic lymphomas were double positive or double negative (6/8). The main clinical, hematologic, and biochemical features were generalized (28/46) or regional lymphadenopathy (16/46), hepatosplenomegaly (15/46), extranodal involvement (11/46), mediastinal mass (9/46), and leukemia (8/46), which were mainly present in cases of lymphoblastic lymphomas and hypercalcemia (16/46).

Adult T-cell leukemia/lymphoma associated with HTLV-1 infection in a Brazilian adolescent

We present the case of a 15-year-old patient infected with HTLV-1 who developed a cutaneous T-cell lymphoma, confirmed by histopathological and immunohistochemical examination, as well as clinically and hematologically confirmed leukemia. The patient died 3 months after initial presentation of the disease. The rarity of the disease in this age group justifies the present report.

HTLV-I-associated granulomatous T-cell lymphoma in a child

Adult T-cell leukemia/lymphoma (ATLL) is a T-cell malignancy closely associated with human T-cell lymphotropic virus-1 (HTLV-I). Because of its long latency period, ATLL occurs almost exclusively in adults. We report a case of a 13-year-old boy with an 8-year history of skin eruptions. After complete evaluation, a diagnosis of HTLV-I-associated lymphoma/leukemia was made. The T-cell lymphoma exhibited a granulomatous histomorphology. There have been very few reports of ATLL presenting in childhood and none, to our knowledge, demonstrating granulomatous histology. We conclude that ATLL may rarely present as a chronic granulomatous eruption in a child.

Parathyroid hormone-related protein

We review the current state of knowledge of the molecular properties and actions of parathyroid hormone-related protein (PTHrP) both in cancer patients and in normal physiology. PTHrP is a common product of squamous cancers and is the major mediator of the syndrome of humoral hypercalcemia of malignancy (HHM) by its actions through parathyroid hormone receptors in bone and kidney. Recently developed radioimmunoassays and tissue localization techniques indicate that PTHrP is produced by many more cancers than was originally indicated by clinical studies and that it contributes significantly to malignancy-related hypercalcemia associated with other etiologies, for example, cancers metastatic to bone and hematological malignancies. The gene encoding PTHrP is complex, with multiple exons coding for up to 12 alternate transcripts and three different length proteins, potentially in a tissue-specific manner, by the use of three promoters. Its expression is regulated by hormones and growth factors, and the untranslated exons display features in common with many cytokine genes. Although potential endocrine actions of PTHrP are evident in fetal development, further evidence suggesting that the normal physiological role of PTHrP is predominantly as a locally produced regulator/cytokine comes from localization studies and investigations of its actions in a variety of tissues. Such studies indicate that in addition to its parathyroid hormone-like actions, PTHrP has multiple activities, including those in fetal development, placental calcium transfer, lactation, smooth muscle relaxation, and on epithelial cell growth. Although PTHrP was discovered because of its production by cancers, evidence for its actions as a local regulator highlights the importance of understanding its roles not only in the etiology of HHM in cancer patients but also in normal tissues.

Clinicopathologic study of 212 cases of peripheral T-cell lymphoma among the Japanese

BACKGROUND

Postthymic/peripheral T-cell malignancy shows significant histopathologic and clinical diversity, even in its prognosis, and the correlations remain to be debated.

METHODS

The clinicopathologic features of 212 Japanese patients with these neoplasms were investigated.

RESULTS

There were 131 male and 81 female patients, whose ages ranged from 2 to 90 years (mean, 51.7 years). Lymphadenopathy was the most frequent clinical presentation, and the patients also had frequent skin lesions, hyperimmunoglobulinemia, hypercalcemia, and a rapid clinical course. Furthermore, the differences in the histologic features of each subcategory reflected the clinical pictures. The immunophenotypic analysis was indispensable in establishing a correct diagnosis, and the high-grade tumors often showed loss of pan-T antigens.

CONCLUSIONS

The histopathologic classification proposed by Suchi et al., which has been incorporated into the updated Kiel classification, showed a good prognostic correlation.

Peripheral T-cell lymphoma: a clinicopathological study of 41 cases and evaluation of the prognostic significance of the updated Kiel classification

A total of 41 non-cutaneous peripheral T-cell lymphomas were classified following the updated Kiel classification. Of these, 20 cases belonged to the low-grade group (T-cell chronic lymphocytic leukaemia, 3; lymphoepithelioid, 5; angioimmunoblastic, 4; pleomorphic small cell, 8) and 21 to the high grade group (pleomorphic medium and large cell, 11; immunoblastic, 3; large-cell anaplastic Ki-1 positive, 7). Seventy per cent showed a CD4+/CD8-phenotype, 39% a defective phenotype and 88% an activation phenotype. Eighty per cent had B-symptoms, 63% hepatomegaly, 48% splenomegaly and 26% had involvement of more than three lymphoid areas. Bone marrow was infiltrated in 34%, central nervous system in 4%, lung in 12% and skin in 14.6%. Seventeen per cent presented with extranodal disease and 82.8% had stage III/IV disease. Hypergammaglobulinaemia was found in 29%, hypercalcaemia in 7%, raised LDH serum levels in 58% and HTLV-I antibodies in only one case. Of the 37 treated patients 18 (48%) achieved a complete remission, but 33% relapsed. Mortality was 59% and actuarial overall survival at 38 months was 0.32. In the comparison of the clinical, analytical and immunophenotypic variables and outcome between low and high grade groups, only the average of bone marrow infiltration in the low grade and stage I-II, presence of defective phenotypes and higher Ki-67 positivity in the high grade group were significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary T-cell lymphoma of the gastrointestinal tract associated with human T-cell lymphotropic virus type I. An analysis using in situ hybridization and polymerase chain reaction

BACKGROUND

During a population-based local cancer registry, a peculiar type of T-cell lymphoma restricted to the gastrointestinal tract was found in patients living in southwestern Japan.

METHODS

Five cases of gastrointestinal (GI) tract T-cell lymphoma were analyzed with immunohistologic examination, ultrastructural analysis, in situ hybridization (ISH), and polymerase chain reaction (PCR).

RESULTS

All cases satisfied the criteria of primary GI tract lymphoma at presentation or operation. Four showed a close relationship to human T-cell lymphotropic virus type I (HTLV-I). Those four had positive results for anti-HTLV-I antibody and positive surface markers for CD4, positive hybridization signals by ISH, and HTLV-I gene products by PCR, but they had no lymphoma cells in peripheral blood or bone marrow. The fifth case showed negative signals by ISH and PCR.

CONCLUSIONS

These findings suggest that some of the putative adult T-cell leukemia/lymphoma (ATLL) types can be further classified as GI-tract-type lymphoma. The prognosis for the GI tract type is as poor as it is for conventional ATLL.

Case report: adult T-cell leukemia/lymphoma associated with recurrent strongyloides hyperinfection

Adult T-cell leukemia/lymphoma (ATLL) was demonstrated postmortem in a 47-year-old woman initially manifesting severe hypercalcemia and a vertebral compression fracture. Hyperinfection with Strongyloides stercoralis preceded the appearance of ATLL by several months and ultimately dominated the terminal course. Although HTLV-I and S. stercoralis commonly infect the same host, only three other cases of concomitant ATLL and hyperinfection have been reported in English. The apparent rarity of this association suggests that immunologic sequelae of ATLL do not predispose to dissemination and multiplication of Strongyloides. Observations pertinent to this conclusion are reviewed.

Lymphoid proliferation and lymphoma associated with human retroviruses (HTLV and HIV)

There are rapidly increasing opportunities for dermatologists to see patients suffering from retrovirus infections. The HTLV-I was the first class of human oncogenic retrovirus that was found in cultured cells of a patient with skin manifestations similar or identical to those of CTCL (MF). It was soon recognized as the agent causing ATLL. The skin manifestations, histopathology, and immunophenotypes of ATLL share many similarities with MF and SS. Both HTLV-I and HIV-I (HTLV-III) cause immunodeficiency with an increased susceptibility to opportunistic infections. Persistent generalized lymphadenopathies are the initial manifestations of most of the HIV infections. The incidence of lymphoid malignancies is expected to become much higher as the life span of AIDS patients is prolonged. They can have both B-cell and T-cell non-Hodgkin lymphomas, although the incidence of the latter (B-cell lymphoma) is still much higher than that of the former. All human retroviruses are transmitted in similar ways.

1,25-Dihydroxyvitamin D-related hypercalcemia in lymphoma: two case reports

We report two patients with non-Hodgkin's lymphoma in whom hypercalcemia and elevated 1,25 dihydroxyvitamin D (1,25-(OH)2D3) levels developed in the absence of any lytic bone lesions. Hypercalcemia responded only transiently to glucocorticoids which were ill tolerated. Intravenous APD administration was needed to circumvene hypercalcemia. Humoral hypercalcemia of malignancy is discussed. Our cases confirm that hypercalcemia associated with elevated 1,25-(OH)2D3 may occur in malignant lymphoma.

Peripheral/post-thymic T-cell lymphomas: a spectrum of disease. Clinical, pathologic, and immunologic features of 78 cases

The clinical, pathologic, and immunologic features of 78 cases of peripheral/post-thymic T-cell lymphomas are described. These neoplasms were extremely heterogeneous and were classified as small lymphocytic, mixed small and large cell, large cell, lymphoepithelioid cell, angiocentric, and adult T-cell leukemia/lymphoma type. Some cases revealed angioimmunoblastic or Hodgkin's-like features. These neoplasms mainly affected older adults (mean age, 57 years; median age, 60 years). Lymphadenopathy represented the most frequent clinical presentation, although most patients demonstrated both nodal (87%) and extranodal involvement (77%) during the course of disease. Sites of extranodal disease included skin/soft tissue, spleen, lung, liver, bone, gastrointestinal tract, central nervous system, peripheral blood, nasopharynx, and retrovaginal tissue. Splenomegaly at presentation was most frequently observed in lymphoepithelioid cell lymphomas. Angiocentric lymphomas involved lung. A mediastinal presentation was typically observed in young adults and associated with a poor prognosis. Patients with gastrointestinal lymphomas presented with bleeding and/or malabsorption. B symptoms were present in most cases (65%). Hypercalcemia occurred in four patients. Phenotypic studies of T-cell antigens demonstrated the loss of one or more pan-T-cell markers in eight of 47 cases evaluated. Assessment of T-cell subsets revealed a helper/inducer phenotype for nearly all immunoreactive cases. For the overall series, 32 patients died of disease (median survival time, 11.5 mo). There was a statistical difference between the combined groups of small lymphocytic and lymphoepithelioid cell types as compared with mixed and large cell types, with a poorer survival for the latter group. Angiocentric and adult T-cell leukemia/lymphoma were associated with poor survival. This series of T-cell lymphomas further documents the marked heterogeneity of this group of neoplasms as well as the poor prognosis observed for certain histologic types.

Parathyroid hormone-related protein is a possible autocrine growth inhibitor for lymphocytes

Adult T-cell leukemia (ATL)-related cells have the ability to produce a newly-isolated calcium-regulating protein, parathyroid hormone-related protein (PTHrP). The present study revealed that lectin-stimulated normal lymphocytes produce immunoreactive (IR)-PTHrP. When the T-cell-enriched fraction was purified from normal lymphocytes and then treated with lectin, a similar amount of IR-PTHrP was detected, suggesting that IR-PTHrP is an actual product of T-lymphocytes. A biologically active fragment of PTHrP, PTHrP(1-34), suppressed DNA synthesis in lectin-stimulated lymphocytes at concentrations greater than 50 pg/mL; the same concentration range of IR-PTHrP detected in the cultured media of lectin-stimulated lymphocytes. Therefore, it is reasonable to postulate that PTHrP is a cytokine inhibiting the cellular growth of normal lymphocytes.

Proposals for the classification of chronic (mature) B and T lymphoid leukaemias. French-American-British (FAB) Cooperative Group

Peripheral blood, bone marrow films, and bone marrow biopsy specimens from 110 patients, well characterised by clinical and laboratory studies, including electron microscopy, were reviewed, to determine proposals for the classification of chronic (mature) B and T cell leukaemias. On the basis of cytology and membrane phenotype the following disorders were defined: (i) B cell type: chronic lymphocytic leukaemia (CLL); CLL of mixed cell type, which includes cases with more than 10% and less than 55% prolymphocytes (CLL/PL), and a less well defined form with pleomorphic lymphocytes but less than 10% prolymphocytes; prolymphocytic leukaemia (PLL); hairy cell leukaemia (HCL); HCL variant; splenic lymphoma with circulating villous lymphocytes; leukaemic phase of non-Hodgkin's lymphoma (follicular lymphoma, intermediate, or mantle zone lymphoma and others); lymphoplasmacytic lymphoma with peripheral blood disease (mostly Waldenström's macroglobulinaemia); and plasma cell leukaemia. (ii) T cell type: T/CLL, which was differentiated from reactive T/lymphocytosis; T/PLL; adult T cell leukaemia/lymphoma; and Sézary's syndrome. The recognition of distinct entities within the B and T cell leukaemias seems to have clinical and epidemiological connotations. It is hoped that these proposals may serve as the basis for further work, discussion, and improved management of patients.

Hypercalcemia and vitamin D metabolism in Hodgkin's disease. Is there an underlying immunoregulatory relationship?

Hypercalcemia is not common in Hodgkin's disease, but in reported cases is often unassociated with bone involvement. A case is presented demonstrating a mechanism involving elevated levels of 1,25-dihydroxy vitamin D3 (calcitriol). Similar cases in the literature are reviewed. Data implicating calcitriol as a hematolymphoid regulatory hormone are discussed as they may relate to lymphomas, leukemias, and paraneoplastic lymphocyte and monocyte/macrophage activity.

Differences in prognostic factors between leukemia and lymphoma type of adult T-cell leukemia

Prognostic factors affecting the survival of adult T-cell leukemia (ATL) patients were analyzed in three groups: total cases, leukemia type cases, and lymphoma type cases. Factors found to be important overall, i.e. for total cases, were leukocyte count, ATL cell ratio in the peripheral blood, serum calcium levels and lactate dehydrogenase (LDH) level. Of those, LDH level proved not significant when evaluated separately for leukemia type or lymphoma type cases. Leukocyte count and ATL cell ratio were significant in leukemia type patients, whereas it was serum calcium level that was significant in lymphoma type; there were mutually exclusive sets of factors for the two groups. Thus, prognostic factors for ATL patients should be considered separately for each type of the disease.

Production of parathyroid hormone-related protein in adult T-cell leukemia cells

Human parathyroid hormone-related protein (PTHrP) mRNA was detected in peripheral leukemic cells obtained from adult T-cell leukemia (ATL) patients as well as in cultured human T-cell leukemia virus type I (HTLV-I)-infected T-cell lines. In contrast, PTHrP mRNA was not detected in other types of leukemic cells. Using radioimmunoassay, immunoreactive PTHrP was also detected in the spent media of HTLV-I-infected T-cell lines. These results suggest that PTHrP plays an important role in developing the hypercalcemia frequently observed in ATL patients.

T-cell lymphoma: a morphological, histochemical and immunological study of nine Chinese cases

Nine cases of T-cell lymphoma presenting in the Guizhou province of China between 1982 and 1984 are reviewed. Seven of the patients were male; seven patients have died, the mean survival period being 22 months. The clinical features resembled those reported in Japanese cases, but skin lesions were absent. Histologically three cases were classified as of lymphoblastic type, three as pleomorphic cell type, two as clear cell type and one as immunoblastic-lymphadenopathy-like T-cell type.

Non-Hodgkin's lymphoma associated with hypercalcemia and increased activity of serum angiotensin-converting enzyme

We describe two patients with diffuse non-Hodgkin's lymphoma, hypercalcemia, and increased activity of serum angiotensin-converting enzyme. A mechanism similar to that operative in sarcoidosis is speculated to have caused the hypercalcemia. A lymphokine elaborated by the malignant lymphoma may cause activated macrophages to produce 1,25-dihydroxyvitamin D3.

Clinical analysis of 33 patients with adult T-cell leukemia (ATL)-diagnostic criteria and significance of high- and low-risk ATL

The clinical characteristics of 33 patients with adult T-cell leukemia (ATL) are described. All patients were born and have lived in Miyazaki Prefecture (southwest of Japan). Because of a wide range of clinical presentations and courses, they were subdivided into 2 groups. In the high-risk group, patients presented with high white-cell counts (WBC greater than or equal to 20,000/microliter) and over 30% of abnormal lymphoid cells (18 patients) and hypercalcemia with a low percentage of leukemic cells (5 patients). In this group the median survival time was only 3 months despite various modes of treatment. In contrast, patients of the second group exhibited a low percentage of abnormal lymphoid cells (WBC less than 20,000/microliter and/or leukemic cells less than 30%) and had no hypercalcemia (8 patients). Their clinical course was chronic with a median survival of 8 months, regardless of modalities of treatment. Two patients went through a period when the number of circulating leukemic cells was low (less than or equal to 5%) before overt leukemia appeared. Other clinical features, signs, symptoms, routine laboratory data, serum anti-ATL-associated antibody, cell membrane markers and cytogenetic studies were similar to those observed in other districts of Kyushu island.

Fulminant cutaneous T-cell lymphoma and Sézary syndrome

The term cutaneous T-cell lymphoma (CTCL) has recently been coined to describe a group of rare lymphoproliferative T-cell disorders classically beginning in the skin and pursuing a chronic, progressive, and indolent course eventually followed by visceral involvement. This term encompasses the spectrum of the traditional mycosis fungoides and Sézary syndrome. A unique case of CTCL that developed a fulminant course leading to death within a few months following the initial symptoms is presented. The clinical course bears a striking similarity to a group of acute T-cell malignancies, while the cytologic-pathologic findings favor the diagnosis of Sézary syndrome. Regardless of the exact classifications, this entity appears to be a highly malignant T-cell disorder, resistant to chemotherapy.

Peripheral T-cell lymphoma. A clinical, histologic, and immunologic study of five cases

The authors describe five white patients with peripheral T-cell lymphoma. Four patients were older than 65 years. All cases presented with a short clinical course and advanced stage at the time of diagnosis. Clinical manifestations included asthenia, weight loss, peripheral and abdominal lymphadenopathy. One case showed tonsillar involvement and subcutaneous lymph node enlargement; hepatomegaly was present in four cases, two of them with splenomegaly. Only one case presented peripheral lymphocytosis and antibodies to human T-leukemia virus. Although three cases were classified as diffuse mixed lymphomas and two as poorly differentiated lymphocytic lymphomas, there were some common characteristics: diffuse infiltration by different proportions of small lymphoid cells and large immunoblasts, some of them multinucleated and similar to Reed-Sternberg cells; accumulation of histiocytes, plasmacytosis, eosinophilia, venular proliferation and compartmentalization were also found. Bone marrow infiltration was observed in two patients. Results of monoclonal markers showed four cases to be OKT4+ and the other OKT8+. The morphologic and immunologic characteristics of these patients were typical and similar to those reported from other geographical areas.

T lymphomas associated with human T-cell leukemia-lymphoma virus may show phenotypic and functional differences from adult T-cell leukemias

We report phenotypic and functional characterization of lymph node cells from 27 patients with T lymphoma from the Nagasaki district of Japan. Nagasaki is one of several areas where adult T-cell leukemia is endemic, and sera from 18 of 23 patients examined (78.3%) were positive for antibody to adult T-cell leukemia-associated antigen. The majority of cases (24 of 27) showed the Leu-2a-, 3a+, MASO36c- phenotype similar to adult T-cell leukemia, but seemed to be subdivided into four groups according to the presence or absence of Leu-1 antigen and the receptor for sheep erythrocytes (SRBC). Eleven cases had both Leu-1 antigen and the receptor for SRBC (E-RFC+, Leu-1+, 2a-, 3a+), but 6 cases lacked Leu-1 antigen (E-RFC+, Leu-1-, 2a-, 3a+), 4 cases lacked receptors for SRBC (E-RFC-, Leu-1+, 2a-, 3a+), and 3 cases lacked both of these markers (E-RFC-, Leu-1-, 2a-, 3a+). The effects of lymph node T cells on pokeweed mitogen (PWM)-induced normal B-cell differentiation was studied in 10 cases. Lymph node T cells of 5 cases showed helper activity without any suppressor activity, and 2 cases showed suppressor activity with almost no detectable helper activity, similar to adult T-cell leukemia cells. Two other cases lacked particular functional effects. These results suggest the possibility that Leu-3a+ T-cell lymphoma may be functionally subdivided into at least two types, a helper type and a suppressor (adult T-cell leukemia) type.

A lymphoproliferative disorder of T gamma cells with the phenotype of cytotoxic/suppressor T-cell

A 25-yr-old Japanese male showed unique T gamma cell proliferation different from cases reported previously. His clinical and hematological features were characterized by persistent high fever and the appearance of large lymphocytes with abundant cytoplasm and azurophilic granules in the peripheral blood (11% of the leukocyte differential count) and the ascitic fluid. These lymphocytes showed the ability to bind the Fc portion of IgG and they beared the antigen of cytotoxic/suppressor T-cell defined by monoclonal antibodies. T-cells from this patient suppressed the immunoglobulin production of normal B-cells by pokeweed mitogen, although a polyclonal hypergammaglobulinemia was observed in the serum. Chromosomal abnormality indicated the malignant nature of the proliferating T gamma cells in this patient. The clinical, hematological, and immunological findings characterized the disease of this patient as a distinct entity among the lymphoproliferative disorders of T-cell origin.

Multilobated B cell lymphomas. A study of 7 cases

Seven cases of multilobated lymphomas with B cell surface markers are presented. Clinical, histological, ultrastructural and immunohistochemical features are detailed. These observations serve to underscore the importance of not relying on morphology alone for the phenotypic classification of non-Hodgkin's lymphomas.

Immunophenotypic classification of lymphoblastic leukaemia and lymphocytic lymphoma--an experience in the south-western area of the Cape Province of South Africa

Adequate tumour material was obtained for phenotypic classification using a standard library of monoclonal antibodies from 81 previously untreated patients with acute lymphoblastic leukaemia (ALL), chronic lymphocytic leukaemia (CLL), or lymphocytic lymphoma (LL). Sixty-one individuals were adults and 20 were children of 14 yr or younger. Fifty-eight of the patients (72%) had acute lymphoblastic leukaemia and the remaining 23 (28%) had chronic lymphocytic leukaemia or lymphocytic lymphoma. Considering only the patients with acute lymphoblastic leukaemia (n = 58) the median age was 19 yr (range 3-69 yr): 9% were black, 43% were coloured, 48% were white, and the distribution between adult (n = 38) and paediatric patients (n = 20) was comparable. Complete remission rate in the adults was 58% and in the paediatric group 85%. For the total group (n = 58) median duration of survival was 59 weeks for common, 39 weeks for null, 63 weeks for T-ALL, and 13 weeks for B-ALL subtypes. In both the common and the null groups overall and disease-free survival was superior in the children. In contrast, no difference was evident in the T-ALL group, which was also notable for its high incidence in young coloured males. The 15 patients with CLL and eight with LL were adults and all the cells were phenotypically of B lineage: in view of the small numbers no comments are possible about ethnic differences. A multi-centre collaborative study is needed to define the epidemiology of haematologic malignancy in South Africa, with emphasis on differences among ethnically distinct subpopulations.

Detection of adult T-cell leukemia-associated antigen in T-cell malignancies in the Nagasaki district of Japan

Adult T-cell leukemia-associated antigen (ATLA), a human retrovirus-associated antigen, and anti-ATLA antibodies were examined in 52 cases of T-cell malignancies in the Nagasaki district in southwestern Japan, which is known to be an ATL endemic area. These T-cell malignancies included 27 cases of ATL, 2 cases of T-cell chronic lymphocytic leukemia (T-CLL), 18 cases of T-cell lymphoma, and 5 cases of mycosis fungoides. Using the immunofluorescence method, ATLA-positive cells were detected in short-term mass culture of mononuclear cells from 22 of the 27 ATL patients, both T-CLL patients, 17 of 18 T-cell lymphoma patients, and 3 of the 5 mycosis fungoides patients. In an ATL patient in whom a high percentage of ATLA-positive cells were detected, many type C virus particles were observed in the extracellular space of the cultured mononuclear cells with an electron microscope. Sera from all 27 of the ATL patients, the 2 T-CLL patients, 15 of the 18 T-cell lymphoma patients, and 4 of the 5 mycosis fungoides patients were anti-ATLA antibody positive. These results indicate the possible participation of the retrovirus, ATL virus (ATLV), in these T-cell malignancies in ATL-endemic areas.

Epitheliotropic lymphoma of the small bowel. Report of a fatal case with cytotoxic/suppressor T-cell immunotype

The authors report the clinical, pathologic, and immunologic features of a case of jejunal cytotoxic/suppressor T-cell lymphoma associated with intractable malabsorption. Histologically, the tumor exhibited striking involvement of small bowel surface and glandular epithelium, and of epithelium in sites of disease dissemination. This epitheliotropism consisted of both cell clusters resembling Pautrier 's microabscesses and single cells within epithelium. Grossly, the jejunal mucosal fold pattern was completely obliterated by lymphoma which formed miliary nodules and multiple distinct tumor masses. Despite aggressive chemotherapy the patient developed widespread disease, and died 11 months after presentation. At autopsy, in addition to disseminated lymphoma, there was a notable activation of hematopoiesis evidenced by extensive extramedullary hematopoiesis and bone marrow hypercellularity. Many lymph nodes spared by the lymphoma showed a polyclonal proliferation of plasma cells and immunoblasts. In view of recent immunologic evidence that normal cytotoxic/suppressor T-cells selectively home to the gut surface epithelium, striking tumor cell epitheliotropism may be a morphologic marker for visceral lymphomas of cytotoxic/suppressor T-cell origin. This unique case broadens the clinical and morphologic spectrum of T-cell disorders.

Cutaneous manifestations in chronic lymphocytic leukemia

Cutaneous lesions arising during the course of chronic lymphocytic leukemia (CLL), generally of the B-cell type, are frequent. Three types of cutaneous manifestations must be differentiated: (1) specific lesions, (2) cutaneous manifestations closely related to the disease but without a leukemoid infiltrate and (3) associations with various dermatologic conditions. The various clinical features are discussed.

Tumor viruses, oncogenes, and human cancer

We review the biology of transforming retroviruses and their relationship to cellular transforming genes (tumor oncogenes). Evidence is discussed for the involvement of a retrovirus in a newly described syndrome, "adult T cell leukemia/lymphoma," which has a high incidence of skin involvement. This virus is related to the animal retroviruses which induce tumors in susceptible hosts after a long latent period. Cellular transforming genes encode proteins which directly change the oncogenic potential of a cell. These genes, which are altered forms of normal cellular genes, have been isolated from a wide variety of human tumors. Viral and cellular transforming genes produce their changes by at least two different mechanisms: abnormally high production of the normal protein encoded by these genes, or normal levels of an altered form of the protein.

Adult T-cell lymphoma leukemia in Western countries

A new T-cell disorder has recently emerged: the so-called adult T-cell lymphoma leukemia (ATLL) initially described in Japan. Subsequently, ATLL cases were recognized in patients from the Caribbean. We summarize the clinical and hematological features of 19 published cases from Western countries, in addition to a new case we encountered. The leukemic cells display characteristic morphological features and a T3+T4+T8-T6- surface antigenic phenotype. Overall survival is of short duration, but remission could be obtained in our case despite a subsequent relapse in skin and CNS. Geographic clusters of ATLL cases have led to the discovery of the possible role of a new retrovirus, HTLV, in the genesis of this rare malignancy.

Retroviruses in human leukemia

After decades of work, a retrovirus of true human origin has been isolated first from a U.S. adult case of T-cell lymphoma and then from cases from various regions of the world. This virus, named HTLV-I, is strongly associated with a malignant leukemia-lymphoma of mature T-cells. This disease was first clinically characterized in Japan but subsequently found to cluster in the Caribbean region, areas of the U.S. and in other countries. This retrovirus-associated malignancy has an adult onset and usually a rapidly fatal course. Lymphadenopathy, hepatosplenomegaly, cutaneous infiltration and hypercalcemia are found. HTLV-I has been characterized in detail and shown to be an exogenous retrovirus. HTLV-I infection is detected in normal populations and is endemic in restricted areas of Japan, the Caribbean, South America, and the U.S. Cases of ATL tend to cluster in these areas. Future studies will focus on learning (1) how HTLV-I is transmitted from individual to individual; (2) the nature of the mechanism by which HTLV-I transforms T-cells; (3) whether we can use probes from HTLV-I to detect other (related) retroviruses in other human neoplasms.