Frontline chemoimmunotherapy with fludarabine, cyclophosphamide, alemtuzumab, and rituximab for high-risk chronic lymphocytic leukemia

Frontline chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab (FCR) is associated with superior overall survival (OS) for patients with chronic lymphocytic leukemia (CLL). Alemtuzumab (A) was added to FCR (CFAR) in a phase 2 trial for high-risk untreated patients < 70 years with serum β-2 microglobulin (β2M) ≥ 4 mg/L. Sixty patients were enrolled; median age was 59 years (range, 42-69); 75% were male; median β2M was 5.1 mg/L (range, 4-11.6); and 51% were Rai III-IV. Complete remission (CR) was achieved in 70%, partial remission (PR) in 18%, nodular PR in 3%, for an overall response of 92%. Of 14 patients with 17p deletion, CR was achieved by 8 (57%). Of 57 BM samples evaluated by 3-color flow cytometry at the end of treatment, 41 (72%) were negative for residual disease. Grade 3-4 neutropenia and thrombocytopenia occurred with 33% and 13% courses, respectively. The median progression-free survival was 38 months and median OS was not reached. In conclusion, CFAR is an active frontline regimen for high-risk CLL. Response rates and survival are comparable with historic high-risk FCR-treated patients. CFAR may be a useful frontline regimen to achieve CR in patients with 17p deletion before allogeneic stem cell transplantation.     

The successful treatment of refractory autoimmune hemolytic anemia with rituximab in a patient with chronic lymphocytic leukemia

The most frequent autoimmune complication in chronic lymphocytic leukemia (CLL) is autoimmune hemolytic anemia (AIHA). There are various treatment modalities; however, there is not much experience with the use of the chimeric anti-CD20 monoclonal antibody rituximab in the autoimmune complications of CLL. Here, we present our patient with CLL and AIHA whose AIHA was unresponsive to various treatment modalities. The administration of 375 mg/m(2)/day rituximab weekly for four cycles halted hemolysis and resulted in resolution of the patient's anemia. One year after therapy, the patient is well with a normal blood count. Rituximab might be preferred over other treatment modalities in the autoimmune complications of CLL because it is effective and has fewer side effects than other therapies.     

Mechanism of autoimmune hemolytic anemia in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a malignant clonal expansion of CD5+B lymphocytes. The CD5+B lymphocytes have been postulated to produce autoantibodies. CLL patients may demonstrate features of autoimmunity including autoimmune hemolytic anemia. However, the origin of the autoantibodies causing the hemolysis is not clear. The present studies were performed to determine whether these autoantibodies are the products of the neoplastic B-CLL clones. Immunoglobulins (Ig) were eluted from washed red blood cells (RBC) obtained from two CLL patients at the time they had autoimmune (DAT-direct antiglobulin test - positive) hemolytic anemia. The light chain phenotypes of these eluted autoantibodies were determined and found to be monotypic with exact correlation to the light chain expressed on the surface of the B-CLL clones. Elutions from RBC of DAT negative patients or normal volunteers failed to demonstrate measurable amounts of Ig. In contrast, Ig eluted from RBC obtained from SLE patients with DAT positive hemolytic anemia found to be polyclonal autoantibodies exhibiting both light chain types. Furthermore, CD5+B lymphocytes obtained from the same two CLL patients (DAT+) produce, in vitro understimulation with phorbal myristate acetate (PMA), monoclonal antibodies which react and bind to RBC. Thus these studies provide direct evidence demonstrating that the antibodies causing the autoimmune hemolytic anemia in our two CLL patients are the products of the B-CLL neoplastic clones.     

CD5-negative chronic lymphocytic leukemia with indolent clinical course and autoimmune thrombocytopenia, successfully treated with rituximab

A 59-year-old male with lymphocytosis and thrombocytopenia was asymptomatic without lymphadenopathy or hepatosplenomegaly over 10 years. He was admitted to our hospital because his thrombocytopenia had worsened. The clonal lymphocytes appeared as regular small mature lymphocytes on blood films, and bone marrow biopsy showed diffuse infiltration of mature lymphocytes. However, megakaryocytes also presented. The immunophenotypic analysis by flow cytometry revealed that the lymphocytes were positive for CD19, CD20, CD22, and surface membrane immunoglobulin (SmIg) M and D-lambda and were negative for CD5, CD10, CD11c, CD23, and other lineage markers. Expression levels of CD20 and SmIg were strong. The markers were consistent with CD5- CLL with autoimmune thrombocytopenia. He received rituximab, and a rapid decrease of lymphocytes with concomitant increase of platelets was observed. A few cases of CD5- CLL with a stable clinical course have been reported, thought to be B lymphocytosis of undetermined significance (MLUS). This is the first report of CD5- CLL with indolent clinical course associated with autoimmune thrombocytopenia, successfully treated with rituximab.     

Hydroxyurea in the management of the hematologic complications of chronic granulocytic leukemia

The effect of hydroxyurea in 35 patients with chronic granulocytic leukemia (CGL), who either had entered an accelerated phase of the disease or had experienced excessive myelosuppression following alkylating agents, was studied. By either intravenous or oral administration, the drug was successful in reducing peripheral leukocyte and blast counts in all cases and in reducing splenomegaly in 13 of 17 patients. The median duration of disease control was 75 days in myeloproliferative acceleration and 27 days in frank blastic transformation. Mild nausea and vomiting were experienced by most patients, but reversible bone marrow suppression occured in only three patients. The drug proved useful in 19 patients who demonstrated myeloproliferative acceleration, especially in controlling excessive leukocytosis and/or thrombocytosis. Rapid reduction of an elevated blast cell count was achieved in nine patients who presented in blastic crisis, in an attempt to eliminate the associated risk of cerebral vascular leukostasis. Five patients who required treatment for their disease following splenectomy in the chronic phase were also well controlled. Hydroxyurea appears to have a definite role in the management of these hematologic complications of CGL.     

Combination chemoimmunotherapy with pentostatin, cyclophosphamide, and rituximab shows significant clinical activity with low accompanying toxicity in previously untreated B chronic lymphocytic leukemia

Building on the prior work of use of pentostatin in chronic lymphocytic leukemia (CLL), we initiated a trial of combined pentostatin (2 mg/m2), cyclophosphamide (600 mg/m2), and rituximab (375 mg/m2) for 65 symptomatic, previously untreated patients. Of 64 evaluable patients, 34 (53%) were high Rai risk, 71% were nonmutated for the immunoglobulin heavy-chain variable region gene, 34% were CD38+, and 34% were ZAP-70+. Thirty patients (52%) had one anomaly detected by fluorescence in situ (FISH) hybridization, and 21 (36%) had complex FISH defects. Thirty-eight patients (58%) had grade 3+ hematologic toxicity but minimal transfusion needs and no major infections. Responses occurred in 58 patients (91%), with 26 (41%) complete responses (CRs), 14 (22%) nodular partial responses (nodular PRs), and 18 (28%) partial responses (PRs). Many patients with a CR also lacked evidence of minimal residual disease by 2-color flow cytometry. Examination of prognostic factors demonstrated poor response in the 3 patients with del(17p). In contrast, we found this regimen was equally effective in young versus older (>70 years) patients and in del(11q22.3) versus other favorable prognostic factors. Thus, this novel regimen of pentostatin, cyclophosphamide, and rituximab for previously untreated patients with CLL demonstrated significant clinical activity despite poor risk-based prognoses, achievement of minimal residual disease in some, and modest toxicity.     

Fatal intravascular autoimmune hemolytic anemia after fludarabine treatment for chronic lymphocytic leukemia

We report the case of a patient with chronic lymphocytic leukemia (CLL) who developed fatal intravascular autoimmune hemolytic anemia (AIHA) after fludarabine treatment. He had previously received several treatments including two courses of fludarabine. The direct antiglobulin test (DAT) was negative at diagnosis but was found to be positive with anti-IgG after the first fludarabine treatment. When the patient was treated again with fludarabine nine months later, the DAT became positive with anti-IgG and anti-C3d antiglobulins after the second course of treatment. Abrupt, fatal intravascular hemolysis occurred after the third course. The occurrence of severe AIHA in CLL patients treated with fludarabine has been reported by several authors. Physicians should be aware of the risk of severe AIHA in CLL patients with a history of AIHA or positivation of the DAT during previous fludarabine administration, or in case of secondary fixation of complement to the red cell membrane occurring during fludarabine treatment.     

Fatal intravascular autoimmune hemolytic anemia after fludarabine treatment for chronic lymphocytic leukemia

We report the case of a patient with chronic lymphocytic leukemia (CLL) who developed fatal intravascular autoimmune hemolytic anemia (AIHA) after fludarabine treatment. He had previously received several treatments including two courses of fludarabine. The direct antiglobulin test (DAT) was negative at diagnosis but was found to be positive with anti-IgG after the first fludarabine treatment. When the patient was treated again with fludarabine nine months later, the DAT became positive with anti-IgG and anti-C3d antiglobulins after the second course of treatment. Abrupt, fatal intravascular hemolysis occurred after the third course. The occurrence of severe AIHA in CLL patients treated with fludarabine has been reported by several authors. Physicians should be aware of the risk of severe AIHA in CLL patients with a history of AIHA or positivation of the DAT during previous fludarabine administration, or in case of secondary fixation of complement to the red cell membrane occurring during fludarabine treatment.     

Transient down-modulation of CD20 by rituximab in patients with chronic lymphocytic leukemia

Lymphoid cells in most patients with chronic lymphocytic leukemia (CLL), when treated with rituximab, become CD20-. This is thought to be due to masking of CD20 by rituximab. We used specific antimouse immunoglobulin antibodies to detect rituximab on the surface of CLL lymphocytes and we demonstrate that rituximab is rarely detectable after therapy. Only 3 of 65 patients with CLL had rituximab detectable on their lymphocytes after rituximab therapy despite the fact that most had no detectable CD20 expression. In vitro mixing of CLL or Raji cells with rituximab demonstrated that rituximab was detectable on the surface of cells due to its binding to CD20. However, the addition of plasma led to the down-modulation of CD20 expression, and the rituximab became undetectable. This down-modulation of CD20 protein expression was associated with a down-modulation of CD20 mRNA. CLL cells that lost their CD20 expression regained CD20 expression after 24 hours in culture. These data suggest that rituximab therapy leads to a substantial but transient down-modulation of CD20 expression and that negativity for CD20 in cells from patients treated with rituximab is not necessarily due to CD20 masking. The importance of this down-modulation in the efficacy of current therapy with rituximab needs further investigation.     

Efficacy of rituximab in the treatment of refractory chronic lymphocytic leukemia patient with bone marrow aplasia

Recently, several reports have been published claiming the efficacy of anti-CD20 monoclonal antibody (rituximab) in the treatment of B-cell chronic lymphocytic leukemia (B-CLL) and some related autoimmune complications. We used anti-CD20 monoclonal antibody in a patient with advanced stage and heavily pre-treated B-CLL with a concomitant bone marrow aplasia requiring a remarkable transfusional support of both red blood cells and platelets. The treatment was conducted according to standard dosage and schedule and the patient did not experience any severe side effect. A progressive reduction of transfusions and a certain recovery of bone marrow cellularity was observed after six months from the end of therapy. This case suggests that rituximab can play a role in this subset of B-CLL patients with very few effective therapeutic options and in which the clinical features may be due both to neoplastic proliferation and concomitant autoimmune disorder.     

Severe autoimmune hemolytic anemia in a patient with chronic lymphocytic leukemia responsive to fludarabine-based treatment

Supported by C.N.R., Progetto Finalizzato A.C.R.O., Contract No. 92.02125, PF 39     

Nonablative allogeneic stem cell transplantation for chronic lymphocytic leukemia: impact of rituximab on immunomodulation and survival

OBJECTIVE: To investigate the graft-vs-leukemia effect of allogeneic stem cell transplantation after a nonablative conditioning regimen as treatment for patients with chronic lymphocytic leukemia. PATIENTS AND METHODS: Patients were eligible to treatment if they were refractory or recurred after a prior response to fludarabine. Seventeen patients were treated. All patients received a preparative regimen of fludarabine (30 mg/m(2) daily for 3 days) and intravenous cyclophosphamide (750 mg/m(2) daily for 3 days). Ten patients received rituximab in addition to chemotherapy. The median time from diagnosis to transplant was 67 months. Nine of 17 patients had refractory disease. RESULTS: All patients had engraftment of donor cells. Eleven (65%) did not require platelet transfusions. Ten patients with persistent disease underwent immunomanipulation to augment GVL effects including immunosuppression withdrawal and donor lymphocyte infusion with or without rituximab treatment. Seven of these 10 patients had a complete response and 2 had a partial response; 8 of these 9 responders had received rituximab with their immunomanipulation process. The final response was complete remission in 12 and partial remission in 4 patients for an overall response rate of 94%. Overall survival was 100% for patients who received the combined chemo-rituximab conditioning regimen, vs 14% for those who received chemotherapy alone (p=0.03). CONCLUSION: Our results indicate that a pronounced GVL effect occurs after nonmyeloablative allogeneic hematopoietic transplantation for advanced CLL. This activity might be facilitated by rituximab. Prospective controlled trials are needed to define the role of nonablative allogeneic hematopoietic transplantation for treatment of this disease.     

Successful treatment and re-treatment of resistant B-cell chronic lymphocytic leukemia with the monoclonal anti-CD 20 antibody rituximab

We report on two patients with chemoresistant B-cell chronic lymphocytic leukemia who were treated successfully with the monoclonal anti-CD 20 antibody rituximab. Both patients suffered from severe thrombocytopenia requiring platelet transfusions over a period of several months. Neither chemotherapy nor immunosuppressive agents (corticoids, immunoglobulins) were effective. After four doses of rituximab (375 mg/m² weekly), both patients recovered within a few weeks to hematological partial remission. One patient was re-treated successfully three times after relapses. Both patients were premedicated with prednisone (100 mg) 30 min prior to the infusion to prevent cytokine release and the antibody infusions were well tolerated. Received: 5 May 1999 / Accepted: 18 October 1999