Outcome of pediatric patients with Langerhans cell histiocytosis treated with 2 chlorodeoxyadenosine: a nationwide survey in Japan.

The aim of this study was to assess the outcome of treatment with 2-chlorodeoxyadenosine (2-CdA) in pediatric patients with Langerhans cell histiocytosis (LCH) in Japan. We retrospectively identified 17 pediatric LCH patients treated with 2-CdA. All patients were refractory or reactivated cases who had been initially treated according to the JLSG-02 protocol of the Japan LCH study group. At initiation of 2-CdA therapy, 4 patients had primary refractory multisystem (MS) disease with risk organ (RO) involvement (MS+), 9 patients had reactivated MS disease [5 MS+ and 4 without RO involvement (MS-)], and the remaining 4 patients had refractory/reactivated multifocal bone disease (MFB). Treatment with 2-CdA (4-9 mg/m(2)/day) was administered on 2-5 consecutive days and repeated every 3-4 weeks for a period that ranged from 2 to 12 months. Four primary refractory patients were treated with 2-CdA combined with high dose of cytarabine. In MS+ patients, response to treatment was observed in 5 of the 9 patients. In MS-/MFB patients, 5 of the 8 patients showed response to treatment. In the patients who were primary refractory or had reactivation during initial chemotherapy, 4 of 10 patients showed good response. On the other hand, in the patients having reactivation while off therapy, 6 of 7 patients showed good response. These findings suggest that 2-CdA is effective for reactivated LCH while off therapy.

Activity and toxicity of 2-CDA in Langerhans cell histiocytosis: a single institutional experience.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare disorder characterized by clonal proliferation of immature and abnormal bone marrow derived langerhans cells. Treatment is usually multimodal. Potent anti-monocyte as well as immunomodulatory activity of 2-CDA and its proven efficacy in many lymphoproliferative disorders has made 2-CDA a rational choice in treatment of LCH. AIM: To evaluate the efficacy and toxicity profile of 2-CDA in children with relapsed or refractory LCH. SETTING AND DESIGN: This is a pilot study and we present the initial data of the first seven patients treated at our institution. MATERIALS AND METHODS: Seven patients of relapsed and refractory LCH were enrolled from July 2000 to June 2004. The cohort of seven patients included six males and one female with a median age at initiation of cladribine was 2.25 years (range, 1.67 to 7.0 years). Three patients had received one prior chemotherapy regimen while the rest were heavily pretreated. Cladribine was administered over two hours IV daily for five days and repeated every four weeks. RESULTS: After a median of six courses of cladribine (range, 2 to 9), two (33%) patients achieved PR and two (33%) patients have SD on imaging but are clinically better. None experienced grade 3 or 4 hematologic toxicity. At a median follow-up of 19 months (range, 8 to 52 months), five patients remain alive and one patient has died. CONCLUSION: Our study shows that single agent 2-CDA is active and well-tolerated in children with relapsed or refractory LCH.

Low dose 2-CdA schedule activity in splenic marginal zone lymphomas.

Splenic Marginal Zone Lymphoma (SMZL) is a rare clinicopathological entity among marginal zone lymphomas. SMZL is an indolent lymphoma usually treated by splenectomy. A subset of patients is characterized by a more aggressive clinical course and poor prognosis. Treatment of these cases and second-line therapy for relapsed patients have not been yet identified. We report 10 cases treated with cladribrine (5 mg/m(2)/week) for six courses. Six patients (60%) achieved partial response, two patients (20%) achieved a complete response and the two remaining patients did not respond and died as a result of progression of the disease. The treatment was well tolerated. A total of 60% of the patients had an overall survival rate of 48 months and 24 months progression-free-survival was achieved by 37% with a median time of progression-free-survival of 17 months. Interestingly, in addition to a relevant percentage of hematological remission, some patients also experienced a molecular remission. We conclude that this treatment is safe and well tolerated and is able to induce a substantial number of responses. Our results suggest that this schedule is well tolerated and could be an useful alternative to splenectomy.

2-CdA in the treatment of hairy cell leukaemia.

INTRODUCTION: Hairy cell leukaemia (HCL) is a rare lymphoproliferative disorder. Treatment options available are splenectomy, interferon, DCF and 2-CdA. 2-CdA is considered to have curative potential as proved by the other studies. METHODS: We gave 2-CdA in a dose of 0.09/kg/day as a continuous infusion in sixteen patients of hairy cell leukaemia. RESULTS: Three patients developed neutropenia post transfusion. At the end of three months all patients were in remission. Two patients relapsed at the median follow-up of 15 months. CONCLUSION: 2-CdA in HCL can achieve complete remission, prolonged survival and care as well.

Peliosis hepatis after treatment with 2-chloro-3'-deoxyadenosine.

Peliosis hepatis is an unusual disorder associated with a variety of diseases and treatments. This is the first report of peliosis hepatis associated with administration of 2-chloro-3'-deoxyadenosine. The literature is reviewed.

[2-CDA in treatment of hairy cell leukemia: a comparison between intravenous and subcutaneous administration. Swiss Study Group of Applied Cancer Research]. / 2-CDA bei der Behandlung der Haarzell-Leukämie: ein Vergleich zwischen intravenöser und subkutaner Verabreichung. Schweizerische Arbeitsgemeinschaft für angewandte Krebsforschung.

2-chlorodeoxyadenosine (2-CDA) is very effective in the treatment of patients with hairy-cell leukaemia, with an overall response rate of 80-95%. The standard treatment is a continuous intravenous infusion for 7 days. The bioavailability of 2-CDA after subcutaneous injection is 100%, but the concentration-time profile is completely different compared to continuous intravenous administration. In the present study we compared the intravenous standard treatment (group 1, n = 22; 0.1 mg/kg/d for 7 days, civ.) with subcutaneous administration of 2-CDA (group 2, n = 62; 0.14 mg/kg/d for 5 days, s.c.) in patients with hairy-cell leukaemia. In group 1, 96% (21/22) of patients responded to 2-CDA (complete remission 73%, partial remission 23%) and in the second group 97% were responsive (complete response 76%, 47/62; partial remission 21%, 13/62). The percentage for moderate and severe infections in the trial with intravenous and subcutaneous treatment was 14% and 26% respectively (p = 0.37). We conclude that subcutaneous administration of 2-CDA in patients with hairy-cell leukaemia is feasible and economical and results in comparable responses and toxicity compared to the intravenous standard treatment.

Hairy cell leukemia. What is new forty years after the first description?

Hairy cell leukemia represent 2% of all the leukemias. The etiology is unknown. The diagnosis is based on the peripheral blood examination, showing characteristic lymphoid B cells, with loose lacy chromatin and unconstant cytoplasmic projections. The abnormal lymphoid cells express CD19, CD20, CD22, CD79a, CD25 and CD103. The tumor cells are Sig + with clonal light chain restriction. The treatment is based on recombinant IFN: we discuss the interest and the risks of second malignancy related to the prescription of the purine analogues.

Association of myelodysplastic changes with purine analogues.

We describe the occurrence of myelodysplastic changes (hypogranular myeloid series and Pelger cells, dyserythropoiesis with ring sideroblasts) in five of 31 patients with chronic lymphoproliferative disorders after treatment with purine analogues. The bone marrows of 31 patients with chronic lymphoproliferative disorders before and after treatment with purine analogues were reviewed. The majority of patients had received extensive prior treatment, but none had dysplastic changes prior to treatment with purine analogues. We suggest that a purine analogue may have been responsible for dysplastic change and that further follow-up of this phenomenon is warranted.

2-Chlorodeoxyadenosine (cladribine)-related eosinophilia in patients with lymphoproliferative diseases.

Eosinophilia and allergic skin reactions are uncommon events after 2-chlorodoxyadenosine (2-CdA, cladribine) administration. A multicentre retrospective analysis of eosinophilia in 360 patients treated with 2-CdA for lymphoid malignancies has been made. B-cell chronic lymphocytic leukaemia (B-CLL) was diagnosed in 153, hairy cell leukaemia (HCL) in 68, low-grade non-Hodgkin's lymphoma (LGNHL) in 119, high-grade NHL in 2 and Waldenstrom's macroglobulinaemia (WM) in 18 patients. 2-CdA was administered at a dose 0.12 mg/kg/d in 2-h intravenous infusion for 5 consecutive d. The courses were repeated monthly. Patients with HCL received 1 cycle of 2-CdA, with NHL 2-6 (mean 3.5) cycles and with B-CLL 3-6 (mean 5) cycles. Twenty patients (5.5%), including 5 with HCL, 6 with LGNHL, 7 with B-CLL and 2 with WM, developed peripheral blood eosinophilia. The mean values of absolute eosinophil count were 0.78x10(9)/l (0.58-1.06x10(9)/l), 0.71x10(9)/l (0.52-1.3x10(9)/l), 85 (0.56-1.82x10(9)/l) and 0.75 (0.74-0.76x10(9)/l), respectively. Eosinophilia occurred in 13 patients after 1 course, in 4 after 2 courses, and in 5 after > or =3 courses of the therapy. In 17 cases it resolved spontaneously. Allergic skin lesions with pruritus were noticed in 3 patients simultaneously with an increase in eosinophil count. All of them required antihistaminic drugs and/or corticosteroids. One patient with B-CLL experienced repeated episodes of eosinophilia. The highest incidence of 2-CdA-induced eosinophilia was noticed in patients with MW (11.1%) and HCL (7.4%) who received only 1 cycle of this drug and entered a complete remission. This side effect was less frequently observed in LGNHL and B-CLL, i.e. in 5.0% and 4.6% of cases, respectively. The mechanism of 2-CdA-induced eosinophilia is not clear. It has been postulated that massive tumour cell lysis may trigger a release of IL-5 and probably other cytokines. The allergic mechanism of 2-CdA-induced eosinophilia is also possible, especially in patients with simultaneous skin reactions.

2-chlorodeoxyadenosine (2-CDA) therapy in previously untreated patients with follicular stage III-IV non-Hodgkin's lymphoma.

PURPOSE: This phase II multi-institutional trial was designed to assess response and toxicity of 2-chlorodeoxyadenosine (2-CDA) in patients with previously untreated follicular lymphoma. The clinical significance of detecting cells carrying the t(14;18) translocation (bcl-2/JH rearrangement) in peripheral blood and bone marrow by polymerase chain reaction (PCR) before, during and after treatment was also examined. PATIENTS AND METHODS: Between May 1993 and October 1995, 37 patients were accrued: male/female: 15/22, median age 51 years (range: 20-78), stage III/IV: 9/28. Patients received a total 2-CDA dose of 0.7 mg/kg as continuous s.c. or i.v. infusions over 7 days, every 28 days for a maximum of 5 cycles. A total of 165 cycles were administered. In 25 patients, blood and bone marrow before, during and after treatment were available for PCR analysis of the bcl-2/JH rearrangements. RESULTS: All 37 patients were evaluable for response and toxicity. The overall response rate was 84% (95% confidence interval, 68%-94%) with 14% CR (n = 5) and 70% PR (n = 26) and a median time to treatment failure of 15.7 months. bcl-2/JH rearrangement in peripheral blood and/or bone marrow was found in 10/25 of patients (40%) before treatment and 5 of these became repeatedly negative after 2-CDA therapy. There was no apparent association between bcl-2/ JH result and response. In 11 patients, 2-CDA was stopped because of progressive disease (n = 4), myelotoxicity (grade 2-3, n = 4), and other causes (n = 3, pulmonary embolism, metabolic disorder, and patient's decision). Four patients (11%) suffered from infections (grade 2-3). In 6 patients, persistent thrombocytopenia of 7.5 months (range: 3-21) occurred after completion of the 5 cycles. CONCLUSION: 2-CDA is active in untreated follicular lymphomas, but time to treatment failure suggests no advantage compared with standard treatment and toxicity on haematopoietic stem cells appears to be more pronounced. Molecular remission is induced in a considerable proportion of patients with disappearance of the bcl-2/JH rearrangement, and its possible significance as a predictive factor for quality of response and relapse warrants further study.

2-Chlorodeoxyadenosine: an active agent in the treatment of cutaneous T-cell lymphoma.

Cutaneous T-cell lymphomas are disfiguring malignant lymphoproliferative disorders for which standard therapy has been principally palliative. 2-Chlorodeoxyadenosine (2-CdA), a new purine analogue resistant to degradation by adenosine deaminase that has substantial activity against lymphoid neoplasms, was administered to 16 patients with cutaneous involvement by T-cell lymphoma. All patients had failed topical treatment modalities and/or systemic therapies. Fifteen patients were evaluable; one patient was not evaluable due to incomplete therapy and follow-up. The overall response rate was 47%. Three of 15 patients (20%) achieved complete responses and four of 15 patients (27%) achieved partial responses. The median duration of response was 5 months. One patient remains in unmaintained complete remission at 52+ months. Therapy was well tolerated. Myelosuppression was the principal toxicity encountered, occurring in 8 of 15 (53%) patients. 2-CdA is an effective new agent for the treatment of cutaneous T-cell lymphoma and warrants further study both as a single agent and in combination regimens.

2-Chlorodeoxyadenosine treatment of low-grade lymphomas.

PURPOSE: Because of the need to identify effective new agents in the treatment of non-Hodgkin's lymphoma and because of the high activity of the purine analog 2-chlorodeoxyadenosine (2-CdA) against chronic lymphocytic leukemia and hairy cell leukemia, a phase II trial of 2-CdA was initiated in patients with low-grade lymphocytic lymphomas. PATIENTS AND METHODS: Forty patients with low-grade lymphocytic lymphomas including diffuse small lymphocytic, follicular small-cleaved, and follicular mixed histologies were enrolled onto the study. Conventional therapies had failed in all patients, and six patients had lymph node biopsies showing evidence of histologic evolution to a higher-grade lymphoma. A total of 107 courses of 2-CdA were administered. There were 27 males and 13 females. The median age was 59 years (range, 37 to 80 years). Patients had received a median of three prior therapies (range, one to six therapies). RESULTS: An overall response rate of 43% was achieved, with eight patients experiencing complete responses (CRs) and nine patients experiencing partial responses (PRs). The duration of responses ranged from 1 to greater than 33 months without maintenance therapy (median duration of response, 5 months). Histology and prior therapy history did not seem to correlate with responses. Significant toxicity was limited to bone marrow suppression; 18% of patients developed neutropenia, and 30% developed thrombocytopenia. CONCLUSIONS: This phase II trial demonstrates that 2-CdA is an effective antilymphocyte, antineoplastic agent with significant activity as a single agent in patients with recurrent or refractory low-grade lymphocytic lymphoma. Responses were achieved with an acceptable toxicity profile. Further trials of this agent in previously untreated patients and in combination regimens are indicated and will be developed.

Rapid recovery from cytopenia in hairy cell leukemia after treatment with 2-chloro-2'-deoxyadenosine (CdA): relation to opportunistic infections.

Sixteen patients with symptomatic hairy cell leukemia were treated with a single course of 2-chloro-2'-deoxyadenosine (CdA), 0.7 mg/kg total dose. Twelve patients achieved complete remission (CR). One patient with a CD19+/CD5+/CD25- phenotype and one with a pentostatin-treated CD19+/CD25- variant form had minor responses. Two patients with advanced disease and poor performance status died early from invasive mycosis. Three patients recovered from infections caused by cytomegalovirus and by candida. No patient had infections caused by bacteria or by unknown organisms. The median time to full recovery from anemia and thrombocytopenia was 6 and 2 weeks from start of therapy, respectively. Patients with infections, however, recovered at 13 and 5 weeks, respectively. Neutrophil, monocyte, and lymphocyte counts returned to normal at a median of 5, 5, and 10 weeks, respectively. Infections developed more frequently in pancytopenic patients than in those with one or more blood cell count within the normal range (P less than .01). All patients with one or no previous therapy had a CR, whereas those with more than one previous regimen had a lower CR rate (P less than .01). Thus, 1 week of CdA therapy frequently induced CR also in patients resistant to interferon. Toxicity was limited, and recovery from cytopenia was faster than what is reported during interferon therapy.

Treatment of hairy cell leukemia with 2-chlorodeoxyadenosine (2-CdA).

We administered one course of 2-chlorodeoxyadenosine (2CdA) at 4 mg/m2 daily for 7 days by continuous intravenous infusion to 46 patients with hairy cell leukemia. Complete remissions occurred in 36 patients (78%; 95% confidence limits, 63% to 89%), partial remissions in five (11%), and a minor response in one. One patient died of candida sepsis 3 weeks after beginning treatment and three patients were clearly resistant to therapy. These three either had morphologically atypical hairy cells, less than 20% of which expressed Ig light chain on the cell surface, or had failed prior treatment with deoxycoformycin and interferon-alpha. At a median of 37 weeks since discontinuation of therapy, recurrent thrombocytopenia has developed in one patient, whose marrow remains normal, while a bone marrow relapse has occurred in another patient, whose blood counts remain normal. Treatment produced a greater than 50% decrease in neutrophil count in 26 patients, which lasted 3 to 4 weeks and was associated with an increased incidence of febrile episodes. These episodes occurred in 21 patients but were associated with documented infection in only four patients. Decreases in the number of CD4+ lymphocytes appeared to occur regularly after treatment and have persisted for a median of 18 weeks without obvious clinical significance. Although years of follow-up will be needed, our results confirm Piro et al's observation (N Engl J Med 322: 1117, 1990) that 2CdA appears to be highly effective in the treatment of hairy cell leukemia.

A phase I clinical trial of 2-chlorodeoxyadenosine in pediatric patients with acute leukemia.

To evaluate its toxicity and clinical efficacy in children with relapsed or refractory leukemia, we performed a phase I trial of 2-chloro-2'-deoxy-adenosine (2-chlorodeoxyadenosine; 2-CDA) given as a continuous 5-day infusion at doses of 3 to 10.7 mg/m2/d. In this study of 31 children with acute leukemia, the only dose-limiting toxicity was myelosuppression. At the highest dose level, three of seven patients developed fatal systemic bacterial or fungal infections. At dose levels above 6.2 mg/m2/d, significant oncolytic responses occurred in all patients. In addition, there was a significant correlation between both the responsiveness by cell type and dose of 2-CDA, such that more oncolytic responses were noted in acute myeloid leukemia (AML) patients than acute lymphoblastic leukemia (ALL) patients (P = .02). Although this was a phase I trial in heavily pretreated patients with refractory disease, two AML patients treated at 5.2 and 10.7 mg/m2/d, respectively, had complete hematologic responses, and one patient treated at 10.7 mg/m2/d had a partial response. In addition, there was a dose-response relationship in all patients with improved cytoreduction of peripheral blast cells at higher doses of 2-CDA. In vitro evaluation of 2-CDA uptake and anabolism by leukemic blast cells from 22 patients demonstrated that 2-chloro-2'-deoxyadenosine (Cld-AMP) and 2-chloro-2'-deoxyadenosine 5'-striphosphate (CldATP) reached concentrations close to steady-state levels within 1 hour. Intracellular nucleotide disappearance rates were high with half-lives of 1.29 and 2.47 hours for CldAMP and CldATP, respectively. This suggests that continuous infusion is necessary to maintain the desired plasma concentration. The results of this study confirm the antileukemic activity of 2-CDA and the lack of prohibitive nonhematologic toxicity. Phase II trials in patients with AML and ALL are warranted.