Current Status of Therapeutic Approaches to Adult T-Cell Leukemia

More than 2 decades have elapsed since the proposal of adult T-cell leukemia (ATL). Since then, the discovery of the etiologic virus, human T-cell leukemia virus type I (HTLV-I), and the establishment of the diagnostic steps of serum test and molecular study have clearly defined ATL as a distinct disease entity. Because conventional chemotherapy, which is active against other lymphoid malignancies, was proven to be ineffective for treating aggressive forms of ATL, ATL has become the target of several clinical studies for the purpose of improving therapeutic outcomes. Combination chemotherapy exclusively designed for ATL has considerably elevated the treatment response rate in ATL patients, but it has not sufficiently extended the median survival time. The introduction of antiviral agents has led to surprising effects for patients with acute ATL. Monoclonal antibodies seem to be promising, especially for patients with chemotherapy-resistant disease. Unfortunately, these approaches did not prove to be sufficient for most patients with ATL to obtain long-term survival. Recent promising reports on allogeneic stem cell transplantation (allo-SCT) for ATL have suggested that allo-SCT could overcome the limitations that other treatment modalities have not surmounted. More efforts are clearly needed to clarify the usefulness of allo-SCT, especially with reduced-intensity conditioning regimens, for ATL patients.

Adult lymphoblastic lymphoma: a retrospective analysis of 92 patients under 61 years included in the LNH87/93 trials

Since 1987, the GELA has initiated multicenter prospective trials for aggressive non-Hodgkin's lymphomas (NHL). Lymphoblastic lymphomas (LBL) were included in those studies until 1997, and 92 LBL patients under 61 years were identified after histological review. The protocols prescribed high-dose anthracycline regimens, four cycles given every 15 days as induction and lasted for </=6 months. A total of 23 patients underwent high-dose therapy consolidation followed by autologous stem-cell transplantation and 69 received standard chemotherapy regimens. Clinical characteristics showed a male predominance (66%) with a median age of 31 years, bone marrow (BM) involvement (22%), mediastinal involvement (66%) and elevated LDH (62%). At the end of treatment, it was seen that 71% of the patients achieved complete remission; four (4%) patients died during induction; 43 patients relapsed at a median time of 10 months. With a median follow-up of 34 months, the 5-year overall survival (OS) and event-free survival (EFS) rates were 32 and 22%, respectively. The only favorable factor significantly associated with survival was young age. These results are poorer than those obtained in other aggressive lymphomas treated with the same regimens and suggest that adult LBL patients should be treated with acute lymphoblastic leukemia protocols.

Effective therapy for a murine model of adult T-cell leukemia with the humanized anti-CD52 monoclonal antibody, Campath-1H

Adult T-cell leukemia (ATL) develops in a small proportion of human T-cell leukemia virus I-infected individuals. Presently, there is no effective therapy for ATL. A murine model of ATL was produced by introducing leukemic cells (MET-1) from an ATL patient into nonobese diabetic/severe combined immunodeficient mice. The MET-1 cells are activated T cells that express CD2, CD3, CD4, CD25, CD122, and CD52. We evaluated the efficacy of Campath-1H (alemtuzumab; a humanized monoclonal antibody directed to CD52), alone and in combination with humanized anti-Tac (HAT) directed to CD25 (interleukin 2 receptor alpha) or with MEDI-507 directed to CD2. We observed that four weekly treatments with 4 mg/kg HAT significantly prolonged survival of MET-1-bearing mice. However, the survival of mice receiving 4 weeks of 4 mg/kg Campath-1H was significantly longer than that of the group receiving four weekly treatments with HAT (P < 0.001). Treatment with Campath-1H for 4 weeks led to a striking prolongation of the survival of MET-1 ATL-bearing mice that was comparable with that of tumor-free nontreated controls. Using Fc receptor (FcR) gamma(-/-) mice, we found that FcRgammas on polymorphonuclear leukocytes and monocytes are required for Campath-1H-mediated tumor killing in vivo. These results demonstrate that Campath-1H has therapeutic efficacy on ATL in vivo in that the life span of the Campath-1H treatment group was comparable with that of mice that did not receive a tumor or therapy. The main tumor killing mechanism with Campath-1H in vivo involves FcRgamma-containing receptors (e.g., FcRgammaIII) on polymorphonuclear leukocytes and macrophages that mediate antibody-dependent cellular cytotoxicity and/or trigger cross-linking induced apoptosis. This study provides support for a clinical trial of Campath-1H in the treatment of patients with T-cell leukemias and lymphomas.

[Adult T cell leukemia/lymphoma (ATL)]

Adult T cell leukemia/lymphoma(ATL) is an aggressive, fatal malignancy associated with human T-lymphotropic virus type I(HTLV-I). The median survival time of acute- and lymphoma-type ATL is 6 and 10 months, respectively. According to recent reports, nearly half of the ATL patients who received allogeneic hematopoietic stem cell transplantation could survive without disease for over 3 years. However, the population of patients who are eligible for conventional transplantation is extremely limited. Therefore, a reduced-intensity allogeneic stem cell transplantation(RIST) is applied to ATL patients and a multi-center phase I clinical trial is now underway. In our institute, 5 patients, who received RIST, are all alive, with 1 case relapsed after 6 months. Thus, RIST is considered very promising.

Hospital admissions for human T-cell lymphotropic virus type-1 (HTLV-1) associated diseases in Dominica

Human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that is endemic in certain regions of the world, and may account for significant morbidity and mortality among hospitalised patients. Sixty six HTLV-1 seropositive patients admitted to hospital with HTLV-1 associated diseases from 1995-99 were studied. HTLV-1 screening was done with ELISA and confirmed on western blot testing. There were 32 females (48.5%) and 34 males (51.5%). The mean age was 56 years and the age range was 9-89 years. The main associated diseases were tropical spastic paraparesis or HTLV-1 associated myelopathy in 18.2% of cases, acute form of adult T-cell leukaemia/lymphoma 7.6%, lymphomas 15.2%, and ectoparasites/endoparasites in 40.9%. HTLV-1 is associated with diseases in Dominica and association with severe forms of strongyloidiasis and scabies is particularly noted.

Fulminant adenovirus hepatitis following bone marrow transplantation. A case report and brief review of the literature

Adenovirus infections are frequently encountered in immunocompromised patients and transplant recipients. However, fulminant hepatic failure due to adenovirus infection as a fatal complication in bone marrow transplant recipients is extremely rare. We report a case of fulminant adenovirus hepatitis in a 21-year-old allogeneic bone marrow transplant recipient who subsequently died of the disease. The diagnosis was established by histologic and immunohistochemical examination of a liver biopsy and was confirmed by liver tissue and blood cultures.

Peracute onset of severe tumor lysis syndrome immediately after 4 Gy fractionated TBI as part of reduced intensity preparative regimen in a patient with T-ALL with high tumor burden

We report a 30-year-old patient with therapy-refractory T-ALL undergoing unrelated allogeneic PBSCT. He developed severe tumor lysis syndrome (TLS) with extreme biochemical changes, cardiac and neurological symptoms and dialysis-dependent acute renal failure after TBI (4 Gy) on the first day of reduced intensity conditioning (RIC) for unrelated allogeneic PBSCT. The patient's clinical condition was stabilized after beginning daily hemodialysis and treatment for disturbed electrolytes, metabolic acidosis and plasma coagulation, as well as reduction of uric acid by rasburicase. The conditioning therapy and the allogenic PBSCT were scheduled according to the preparative regimen. According to our knowledge, severe TLS induced by 4 Gy TBI has not been reported so far. Regimen-related toxicity using RIC regimen was mild, allowing 30-50% of the patients to have an entirely outpatient transplantation. However, we would like to point out that severe TLS could also complicate PBSCT using RIC regimens in patients with relatively radiation-sensitive malignancies and high tumor burden.

The current status of therapy for adult T-cell leukaemia-lymphoma in Japan

More than 25 years have passed since adult T-cell leukaemia-lymphoma (ATLL) was identified as a distinct clinical entity clustered in the southwestern part of Japan. During these years, its causative agent, Human T-cell leukaemia virus type I (HTLV-I), was found, and remarkable clinical variance of this disease was recognized afterward. Because of the regional occurrence of this disease in the world, young medical scientists whose community is not endemic for this disease may have little understanding of it and may think that it a T-lymphoblastic leukaemia-lymphoma of adult-onset. In Nagasaki prefecture in Japan, where HTLV-I carriers account for 3-5% of the population, the incidence of ATLL is almost the same as the incidence of B-cell lymphomas, and hence ATLL is a matter of major concern. In contrast to the vast accumulation of knowledge about the oncogenic role of HTLV-I and molecular biology of ATLL cells, improvement in the prognosis of patients has not been satisfactorily achieved except for some recent progression. Here, we review the current status of therapy for ATLL in Japan and discuss how best to manage this difficult disease at this point and what next step should be taken.

[Cyclosporin A withdrawal causes spontaneous remission of recurrent subcutaneous tumors after allogeneic peripheral blood stem cell transplantation for adult T-cell leukemia/lymphoma]

A 36-year-old woman was referred to our hospital because of leukocytosis in June 2000, and was admitted to our hospital and diagnosed as having adult T-cell leukemia/lymphoma (ATL; acute type). Complete remission was achieved with eight courses of CHOP therapy, but ATL relapsed and she was readmitted to our hospital in September 2001. Laboratory examination showed elevated levels of serum LDH and soluble IL-2 receptor, and hypercalcemia. CT examinations showed swelling of the abdominal lymph nodes and hepatosplenomegaly. CHOP therapy improved the symptoms, but recrudescence soon occurred. After two courses of salvage therapy which resulted in no remission, the patient received an allogeneic peripheral blood stem cell transplant (allo-PBSCT) from her HLA-matched sibling donor after preconditioning with BU + CY in January 31, 2002. Cyclosporin A (CsA) and short-term MTX were used to prevent GVHD. Bone marrow engraftment was prompt and acute GVHD was not found. Two months later, recurrence was seen in the form of subcutaneous tumors, but the tumors spontaneously disappeared following CsA withdrawal. At the time of writing, eight months after the transplant, remission has been maintained. A graft-versus-leukemia (GVL) effect may have been the curative action in this case.

Successful bone marrow transplantation from an unrelated donor in a patient with adult T cell leukemia

We report a 51-year-old male with adult T cell leukemia (ATL) who received a BMT from an HLA-identical unrelated donor. The ATL proved refractory to chemotherapy, and he underwent BMT conditioned with CY/TBI. Complications of encephalitis of unknown origin were successfully treated with steroid therapy and the patient has been in CR for 16 months after BMT. Human T cell leukemia virus type 1 proviral DNA loads were reduced to undetectable levels in PBMC sampled 12 months after BMT. This encouraging result suggests that BMT from an unrelated donor should be considered for ATL even if the disease is refractory to chemotherapy.

Fusion of mature dendritic cells and human T-lymphotropic virus type I infected T cells: its efficiency as an antigen-presenting cell

Monocyte-derived dendritic cells (DCs) from adult T cell leukemia are impaired in taking up exogenous antigens. To overcome this impairment, we fused unpulsed DCs to human T-lymphotropic virus type I (HTLV-I)-infected CD4(+) T cells (fusion DC-T cells). The efficiency of fusion was 50% and the fusion cells expressed higher HLA-ABC and CD86 Ags than HTLV-I-infected DCs. The fusion DC-T cells stimulated autologous CD4(+) and CD8(+) T cells, but DCs fused to itself or PHA-blasts did not stimulate any subsets. The functionally highest fusion DC-T cells was obtained when a DC and HTLV-I-infected T cells were fused at a ratio of 3:1. Expression of HTLV-Igag Ag on CD4(+) T cells was up-regulated when infected in the presence of 8-azaguanine, and these fusion DC-T cells were quite efficient in induction of higher CD8(+) T cell response. The results suggest that fusion DC-T cells produce functionally competent Ag-presenting cells and may be a likely candidate for immunotherapeutic use.

Interferon-alpha therapy following autologous peripheral blood stem cell transplantation for adult T cell leukemia/lymphoma

In the present report, we describe a case of adult T cell leukemia/lymphoma (ATLL), a 58-year-old woman, successfully treated with interferon (IFN)-alpha following autologous peripheral blood stem cell transplantation (auto-PBSCT). The patient remains in remission with full performance status for more than 12 months. Auto-PBSCT reduced the abdominal lymphoma mass and IFN-alpha eliminated residual tumor cells, possibly through the induction of specific T-cell subsets expressing CD3, CD8 on their surfaces and either IFN-gamma or tumor necrosis factor (TNF)-alpha in cytoplasm. We have treated a total of 4 ATLL patients with auto-PBSCT, including the case presented herein. All other patients treated with auto-PBSCT were not followed by adjuvant chemotherapy or cytokine therapy and relapsed within 3 months after auto-PBSCT. This evidence suggests that the therapeutic success of the present case was attributable to the administration of IFN-alpha immunotherapy following auto-PBSCT.

Eradication of virus-infected T-cells in a case of adult T-cell leukemia/lymphoma by nonmyeloablative peripheral blood stem cell transplantation with conditioning consisting of low-dose total body irradiation and pentostatin

We describe the case of a 55-year-old man with adult T-cell leukemia/lymphoma (ATL) in first remission who underwent nonmyeloablative allogeneic peripheral blood stem cell transplantation with conditioning consisting of 4 courses of pentostatin and low-dose total body irradiation. Complete chimerism in peripheral blood was achieved on day 42 without severe myelosuppression. Concomitantly, the proviral DNA load for human T-cell leukemia virus I (HTLV-I) in peripheral blood mononuclear cells decreased below detectable limits and was still undetectable on day 270. This fact indicates that eradication of ATL cells is feasible by induction of an alloimmune response without high-dose chemoradiotherapy.

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.

Progressive interstitial fibrosis of the lung in sclerodermoid chronic graft-versus-host disease

Sclerodermoid chronic graft-versus-host disease (sGVHD) is a well-known complication in patients with a long history of chronic GVHD. Pulmonary involvement in chronic GVHD presents typically as bronchiolitis obliterans (BO). Pulmonary fibrosis after allogeneic hematopoietic stem cell transplantation (HSCT) is presumed to be caused by the long-term toxicity of the conditioning regimen or the result of lung injury elicited predominantly by viral infections or GVHD. We present two patients with late onset pulmonary fibrosis associated with moderate sGVHD of the skin after HSCT. At the initial diagnosis of chronic GVHD both patients presented with symptoms of interstitial pneumonia. Years later both patients developed moderate to severe interstitial pulmonary fibrosis in association with sGVHD. One patient showed additional clinical and histological signs of BO. While one patient responded to increased immunosuppression including total nodal irradiation (1 Gy), the other patient died due to complications related to pulmonary fibrosis.

Low relapse rate in children with acute lymphoblastic leukemia after risk-directed therapy

PURPOSE

Even though acute lymphoblastic leukemia (ALL) responds well to chemotherapy, relapse remains the major problem. This study documents relapse and survival rates in 85 consecutive children (33 at good risk, 52 at high risk) with ALL diagnosed in 1991 to 1996.

PATIENTS AND METHODS

Until 1993, the New York II protocol for the high-risk group and a combination of UKALL XI (induction) and R blocks of ALL-REZ BFM-87 (intensification) regimens for patients at good risk were used. To reduce toxicity, the protocols were subsequently modified. Consolidation treatment was the same for both groups, consisting of a lower cytarabine dose and methotrexate removal, whereas intensification was changed only for the high-risk group using the BB block of the NHL-BFM-90 protocol. The bone marrow clearance of leukemia was assessed on day 22, and minimal residual disease was detected using polymerase chain reaction analysis of Ig heavy-chain gene rearrangements.

RESULTS

Seventy patients had common precursor B lineage ALL, six had pre-B-ALL, eight had T-ALL, and one had B-ALL. Two patients never achieved remission and died. Six patients died of consolidation-related complications. Four more patients died, two during induction and two during maintenance therapy. Two other children had relapse (2.3%), both of whom were treated with the earlier protocols and then underwent bone marrow transplantation. Four more children with morphologically complete remission showed minimal residual disease (which reached the levels of 1 leukemic cell among 10(2)-10(4) normal cells) with the use of clone-specific probes at several points of the study intervals, but never had relapse. The 5-year overall and event-free survival rates were 86% and 83%, respectively. The 5-year overall survival rates for good-risk and high-risk groups were 94% and 81%; the corresponding event-free rates were 91% and 78%. The 5-year event-free survival rate in the patients at high risk was significantly higher after the protocol change (90% vs. 65%, P = 0.04).

CONCLUSIONS

The modification proved to be effective in diminishing the therapeutic toxicity and improving the efficacy, mainly for the high-risk group.

Remission of severe, intractable autoimmune haemolytic anaemia following matched unrelated donor transplantation

Immune-mediated haemolytic anaemia presenting post allogeneic bone marrow transplantation is often alloimmune in origin due to ABO or minor red cell incompatibilities. Autoimmune haemolytic anaemia is also recognised, is frequently difficult to treat and overall prognosis is often poor, usually from associated problems. Here, we present a case report of autoimmune haemolysis presenting in an 8-year-old boy 6 months post allogeneic bone marrow transplant requiring 4 years of immunosuppressive therapy before remission of haemolysis. This case report highlights the fact that it is possible for haemolysis to resolve post transplant even after years of immunosuppressive therapy.

Pseudoparasitic pneumonia after bone marrow transplantation

We present a female patient from Somalia with an acute lymphoblastic leukemia, who received an allogeneic bone marrow transplantation (BMT) and developed several periods of moderate to severe pulmonary symptoms that were accompanied by pulmonary infiltrates and peripheral blood eosinophilia. After several recurrences an open lung biopsy was performed, which initially gave rise to the diagnosis parasitic infection. Later on this diagnosis was questioned and it was suggested that the structures were artifacts that might have been aspirated. Nevertheless, after the immediately given antihelminthic treatment no peripheral blood eosinophilia occurred anymore, but at that point of time pulmonary function was already severely hampered and eventually led to a lethal complication. With the worldwide increasing migration from Third World countries with a high prevalence of parasitic infections, more patients will receive immunosuppressive therapies in countries less familiar with parasites. This may complicate diagnostic procedures, prevent early recognition and delay adequate treatment. Specific screening for opportunistic parasitic infections of the population at risk before BMT and a great awareness for these infections is strongly recommended.