Severe neutropenia associated with large granular lymphocyte lymphocytosis: successful control with cyclosporin A

Pathophysiologic mechanisms and management of neutropenia associated with large granular lymphocytic leukemia

Large granular lymphocyte (LGL) syndrome includes a spectrum of clonal T cell and natural killer cell chronic lymphoproliferative disorders. These conditions are thought to arise from chronic antigenic stimulation, while the long-term survival of the abnormal LGLs appears to be sustained by resistance to apoptosis and/or impaired survival signaling. T-cell LGL (T-LGL) leukemia is the most common LGL disorder in the Western world. Despite its indolent course, the disease is often associated with neutropenia, the pathogenesis of which is multifactorial, comprising both humoral and cytotoxic mechanisms. This article addresses the pathogenesis of T-LGL leukemia and natural killer cell chronic lymphoproliferative disorder, as well as that of T-LGL leukemia-associated neutropenia. Furthermore, as symptomatic neutropenia represents an indication for initiating treatment, available therapeutic options are also discussed.

2006 Bethesda International Consensus recommendations on the flow cytometric immunophenotypic analysis of hematolymphoid neoplasia: medical indications

The clinical indications for diagnostic flow cytometry studies are an evolving consensus, as the knowledge of antigenic definition of hematolymphoid malignancies and the prognostic significance of antigen expression evolves. Additionally the standard of care is not routinely communicated to practicing clinicians and diagnostic services, especially as may relate to new technologies. Accordingly there is often uncertainty on the part of clinicians, payers of medical services, diagnostic physicians and scientists as to the appropriate use of diagnostic flow cytometry. In an attempt to communicate contemporary diagnostic utility of immunophenotypic flow cytometry in the diagnosis and follow-up of patients with hematolymphoid malignancies, the Clinical Cytometry Society organized a two day meeting of international experts in this area to reach a consensus as to this diagnostic tool. This report summarizes the appropriate use of diagnostic flow cytometry as determined by unanimous approval of these experienced practitioners.

T-cell large granular lymphocytic (T-LGL) leukemia: experience in a single institution over 8 years

T-cell large granular lymphocytic (T-LGL) leukemia is characterized by cytopenia and clonal proliferation of large granular lymphocytes. We identified 26 patients with T-LGL leukemia seen at our institution over a period of 8 years. The majority of the patients were asymptomatic at diagnosis. Nine patients were treated with cyclosporine; one achieved a complete remission, and four had a hematological response. Other treatment modalities included single agent alemtuzumab, alemtuzumab combined with pentostatin, fludarabine, and combination of fludarabine and cyclophosphamide. Significant responses were not seen with any of these treatment regimens. We conclude that cyclosporine therapy may be beneficial for T-LGL leukemia patients. New treatment modalities are needed for these patients.

T-cell large granular lymphocyte leukemia

BACKGROUND

To the authors' knowledge, there is no standard treatment for patients with T-cell large granular lymphocyte (LGL) leukemia. Available data are limited by patient numbers and coexisting pathologies.

METHODS

The authors report on the use of immunosuppressants (cyclosporin A [CSA] and low-dose oral methotrexate [MTX] given continuously) and cytotoxic agents in the treatment of 29 patients with T-cell LGL leukemia age over the past 20 years.

RESULTS

The overall response rate (ORR) to MTX (n = 8 patients) was 85.7% (complete hematologic response [CHR] rate, 14.3%; partial response [PR] rate, 71.4%) with dose-dependent responses observed and safe usage of doses >10 mg/m2 per week in 2 patients. The ORR to CSA (n = 23 patients) was 78.2% (CHR rate, 30.4%; PR rate, 47.8%). The median time to response for both agents was 1 month. Toxicity, although it was minor in most patients and was more common in the CSA group, included second malignancies in 5 patients. An ORR of 67% (all CHR) was attained with pentostatin (n = 4 patients); recurrences developed after a median of 4.6 years. Successful retreatment with pentostatin was possible but with increasing drug resistance. Cyclophosphamide induced CHR that lasted >7 years with bone marrow clearance in 1 of 4 patients. Alemtuzumab induced a PR in 1 patient who had refractory disease.

CONCLUSIONS

Both MTX and CSA were efficacious in the treatment of T-cell LGL leukemia but generally required long-term maintenance therapy. The authors highlight the risks of second malignancies and persistence of bone marrow disease. Although MTX and CSA were effective as first-line therapy, alemtuzumab and pentostatin merit further investigation, particularly for refractory disease.

Neutropenia Associated With T-Cell Large Granular Lymphocyte Leukemia: Long-Term Response to Cyclosporine Therapy Despite Persistence of Abnormal Cells

T-cell large granular lymphocyte (T-LGL) leukemia is clinically indolent, but is associated with severe neutropenia in approximately 50% of cases. The pathogenesis of the neutropenia is unclear. We report reversal of severe neutropenia associated with T-LGL leukemia in five patients treated with cyclosporine (CSA). All five had persistent neutrophil counts below 0.5 × 109/L, two had agranulocytosis, and four had recurrent infections. Increased populations of LGL were present in blood and marrow, with a T-LGL immunophenotype (CD3+CD8+CD16±CD56±CD57+) shown by multiparameter flow cytometry, and clonal T-cell receptor (TCR) gene rearrangements in two of two pretreatment blood samples studied. CSA was initiated at doses of 1 to 1.5 mg/kg orally every 12 hours, with subsequent dose adjustments based on trough serum levels. Four patients attained normal neutrophil counts with CSA alone; one required addition of low-dose granulocyte-macrophage colony-stimulating factor. Time to attainment of 1.5 × 109/L neutrophils ranged from 21 to 75 days. Attempts to taper and withdraw CSA resulted in recurrent neutropenia. Three patients have maintained normal neutrophil counts on continued CSA therapy for 2, 8, and 8.5 years. Two patients died 1.7 and 4.6 years after initiation of CSA despite normal neutrophil counts—one of metastatic melanoma and one of complications after aortofemoral bypass surgery. Despite resolution of neutropenia, increased populations of T-LGL cells have persisted in all patients during CSA therapy, as shown by morphology and flow cytometry and by the presence of clonal TCR gene rearrangements in four patients' posttreatment blood samples. We conclude that CSA is an effective therapy for neutropenia associated with T-LGL leukemia, and that resolution of neutropenia despite persistence of abnormal cells implies that CSA may inhibit T-LGL secretion of yet unidentified mediators of neutropenia.

Neutropenia Associated With T-Cell Large Granular Lymphocyte Leukemia: Long-Term Response to Cyclosporine Therapy Despite Persistence of Abnormal Cells

T-cell large granular lymphocyte (T-LGL) leukemia is clinically indolent, but is associated with severe neutropenia in approximately 50% of cases. The pathogenesis of the neutropenia is unclear. We report reversal of severe neutropenia associated with T-LGL leukemia in five patients treated with cyclosporine (CSA). All five had persistent neutrophil counts below 0.5 × 109/L, two had agranulocytosis, and four had recurrent infections. Increased populations of LGL were present in blood and marrow, with a T-LGL immunophenotype (CD3+CD8+CD16±CD56±CD57+) shown by multiparameter flow cytometry, and clonal T-cell receptor (TCR) gene rearrangements in two of two pretreatment blood samples studied. CSA was initiated at doses of 1 to 1.5 mg/kg orally every 12 hours, with subsequent dose adjustments based on trough serum levels. Four patients attained normal neutrophil counts with CSA alone; one required addition of low-dose granulocyte-macrophage colony-stimulating factor. Time to attainment of 1.5 × 109/L neutrophils ranged from 21 to 75 days. Attempts to taper and withdraw CSA resulted in recurrent neutropenia. Three patients have maintained normal neutrophil counts on continued CSA therapy for 2, 8, and 8.5 years. Two patients died 1.7 and 4.6 years after initiation of CSA despite normal neutrophil counts—one of metastatic melanoma and one of complications after aortofemoral bypass surgery. Despite resolution of neutropenia, increased populations of T-LGL cells have persisted in all patients during CSA therapy, as shown by morphology and flow cytometry and by the presence of clonal TCR gene rearrangements in four patients' posttreatment blood samples. We conclude that CSA is an effective therapy for neutropenia associated with T-LGL leukemia, and that resolution of neutropenia despite persistence of abnormal cells implies that CSA may inhibit T-LGL secretion of yet unidentified mediators of neutropenia.

Response of T-beta CD8+ lymphocytosis-associated neutropenia to G-CSF

Only limited data are reported on the response to granulocyte-colony stimulating factor (G-CSF) of large granular lymphocytosis-associated neutropenia. We report features of such a case who developed a suppurating leg ulcer following a dog bite. G-CSF was used to increase the neutrophil count, allowing the ulcer to be successfully skin grafted.

Cyclosporine treatment of refractory T-cell lymphomas

BACKGROUND

Cyclosporine (cyclosporin A, CSA) prolongs the survival of transplanted organs by reducing the transcription of cytokines, especially interleukin-2, that are thought to mediate T-cell expansion and subsequent graft rejection. Recently, CSA has been suggested as a potentially effective agent in the treatment of T-cell neoplasms. As a result, a Phase II trial of CSA was done in patients with refractory T-cell lymphomas.

METHODS

Patients with peripheral T-cell lymphoma (PTCL) or cutaneous T-cell lymphoma (CTCL) who had disease progression after at least one previous therapy were eligible for participation. CSA was administered orally at a dose of 7.5 mg/kg twice daily, and the patients were followed for disease response and toxicity.

RESULTS

A total of 16 patients were treated. Five patients had PTCL, and 11 had CTCL. Most patients were pretreated extensively with chemotherapy and/or radiation therapy. No responses occurred in patients with PTCL. Two of 11 patients with CTCL responded to therapy. Both patients who responded to CSA had recurrent disease that approached baseline levels within 1 week of discontinuing therapy. A second response occurred in both patients after reinstitution of therapy. Although most patients were removed from the study because of disease progression, renal toxicity was significant.

CONCLUSIONS

Most patients with refractory T-cell lymphomas did not respond to CSA, suggesting that these malignancies are not interleukin-2 dependent or, alternatively, that CSA did not reach its intracellular target. In the two responding patients, the pattern of repeated rapid regression of disease after CSA administration and subsequent rapid recurrence after a temporary halt in therapy suggested that CSA was cytostatic rather than cytocidal or that the clinical remissions were mediated by the antiinflammatory effects of the drug.

Human NK cells in health and disease: clinical, functional, phenotypic and DNA genotypic characteristics

Natural killer (NK) cells are the subject of great current interest because of their possible (in vivo) role in tumour cell surveillance and killing, and because of the potential application of cytokine-modulated NK cells in cancer immunotherapy. In addition, clonal proliferations of NK-associated (NKa) cell populations represent a high proportion of chronic (non-B) lymphoid malignancies and abnormal (both clonal and non-clonal) NKa components are being increasingly reported in association with diverse clinical pictures such as autoimmune disease. This communication extensively reviews what is presently known regarding normal and leukaemic NKa phenotypic diversity, the mechanisms of NK-mediated cytolysis, the role of NK cells in malignancy, and the diagnostic and cellular aspects of malignant NKa proliferations.

Childhood polyclonal T cell lymphocytosis with neutropenia: effects of antilymphocyte globulin and granulocyte colony stimulating factor in vitro and in vivo

The pathogenesis of the neutropenia that occurs in some patients with chronic T cell lymphocytosis is not well understood. We have investigated a 15-year-old girl with this syndrome. Initial committed bone marrow progenitor numbers (CFUgm) were low but markedly increased in vitro following T cell depletion. Similarly a transient correction of neutropenia was observed following in vivo lymphocyte depletion with antilymphocyte globulin. A sustained neutrophil recovery was achieved with daily therapy using recombinant human granulocyte colony stimulating factor (rhG-CSF) despite persistence of the lymphocytosis; during successful therapy CFUgm numbers remained low, and were not increased by the in vitro addition of rhG-CSF. These observations suggest the possibility of an inhibitory regulatory mechanism specifically acting on neutrophil granulopoiesis.

Improvement of pneumonia and arthritis in Felty's syndrome by treatment with granulocyte-macrophage colony-stimulating factor (GM-CSF)

A 63-year old man with Felty's syndrome and pneumonia of unknown origin was treated with GM-CSF. Granulocyte counts increased and arthritis-related symptoms improved under GM-CSF. Pneumonia was treated effectively with antibiotics only during or after GM-CSF application. This suggests, that antibiotic-resistant infections can be treated effectively in patients with Felty's syndrome when granulocyte counts are raised by GM-CSF.