Dhodapkar, MV

Abstract We identified 68 patients with clonal T-large granular lymphocyte (T- LGL) proliferations who were seen at the Mayo Clinic between 1984 and 1992. Nineteen (28%) were asymptomatic at diagnosis, while the rest experienced fatigue (60%), B-symptoms (12%), and recurrent infections (15%). Associated comorbid conditions included rheumatoid arthritis (RA) in 26%. Severe anemia (hemoglobin [Hb] < 8g/dL) and neutopenia (absolute neutrophil count [ANC] < 500/microL) were seen in 19% and 40% of patients, respectively. Immunophenotypic studies showed CD3+, CD8+ phenotype in the majority (72%). Twenty-one patients (31%) have required no therapy, and remain relatively stable with a median follow- up period of 50 months. Treatment was required at either diagnosis (36 patients) or at subsequent follow-up (11 patients). Initial response rates were similar in patients treated with cyclophosphamide (CTX) with or without prednisone (69%), or prednisone alone (73%). Overall, 61 patients (90%) are alive with a median follow-up of 44 months. Actuarial median survival of this entire cohort is 161 months. The presence of anemia or symptoms does not appear to correlate with the tumor burden. In patients requiring therapy, a lower ANC and the presence of B-symptoms/infection were independently associated with a significantly lower probability of achieving a molecular or hematologic complete remission (H-CR). Intermittent immunosuppressive therapy is effective in achieving durable responses in a number of patients. T-LGL proliferations are associated with a favorable prognosis and response to therapy. However, significant heterogeneity exists in clinical presentation and associated comorbid conditions. These disorders should be included in the differential diagnosis of patients with unexplained cytopenias, particularly in the setting of RA and other autoimmune disorders. Analogous to the situation with monoclonal gammopathies, a term such as T-cell clonopathy of undetermined significance (TCUS) may be more appropriate to describe these patients.

Abstract We review the clinical manifestations and long-term outlook of patients with chronic natural killer (NK) cell lymphocytosis. After reviewing more than 1,500 peripheral blood lymphoid flow cytometry reports and molecular genetics data from patients with suspected large granular lymphocyte (LGL) proliferation, we identified 10 patients (median age at diagnosis, 60 years; range, 35 to 76 years; male:female ratio, 3:2) with persistent (greater than 6 months) increase in phenotypically determined NK cells (CD3-CD16+). Southern blot analysis performed on 9 patients showed no clonal T-cell receptor gene rearrangements. Disease duration was measured from time of initial recognition of LGL or NK cell excess (greater than 40% of the lymphocyte fraction). Clinical data from these 10 patients were compared with those from 68 patients with T-cell LGL (T-LGL) leukemia. Currently, all patients are alive (median disease duration, 5 years; range, 0.8 to 8 years). Associated disease manifestations included pure red blood cell aplasia, recurrent neutropenia, recurrent neutropenic sepsis, and vasculitic syndromes, all of which were responsive to immunosuppressive therapy. No patient had palpable lymphadenopathy or splenomegaly. Compared with the patients with T-LGL leukemia, patients with chronic NK cell leukemia has similar lymphocyte counts, associated conditions, treatment responses, and survival but had less neutropenia and anemia.

We review the clinical manifestations and long-term outlook of patients with chronic natural killer (NK) cell lymphocytosis. After reviewing more than 1,500 peripheral blood lymphoid flow cytometry reports and molecular genetics data from patients with suspected large granular lymphocyte (LGL) proliferation, we identified 10 patients (median age at diagnosis, 60 years; range, 35 to 76 years; male:female ratio, 3:2) with persistent (greater than 6 months) increase in phenotypically determined NK cells (CD3-CD16+). Southern blot analysis performed on 9 patients showed no clonal T-cell receptor gene rearrangements. Disease duration was measured from time of initial recognition of LGL or NK cell excess (greater than 40% of the lymphocyte fraction). Clinical data from these 10 patients were compared with those from 68 patients with T-cell LGL (T-LGL) leukemia. Currently, all patients are alive (median disease duration, 5 years; range, 0.8 to 8 years). Associated disease manifestations included pure red blood cell aplasia, recurrent neutropenia, recurrent neutropenic sepsis, and vasculitic syndromes, all of which were responsive to immunosuppressive therapy. No patient had palpable lymphadenopathy or splenomegaly. Compared with the patients with T-LGL leukemia, patients with chronic NK cell leukemia has similar lymphocyte counts, associated conditions, treatment responses, and survival but had less neutropenia and anemia.

We identified 68 patients with clonal T-large granular lymphocyte (T- LGL) proliferations who were seen at the Mayo Clinic between 1984 and 1992. Nineteen (28%) were asymptomatic at diagnosis, while the rest experienced fatigue (60%), B-symptoms (12%), and recurrent infections (15%). Associated comorbid conditions included rheumatoid arthritis (RA) in 26%. Severe anemia (hemoglobin [Hb] < 8g/dL) and neutopenia (absolute neutrophil count [ANC] < 500/microL) were seen in 19% and 40% of patients, respectively. Immunophenotypic studies showed CD3+, CD8+ phenotype in the majority (72%). Twenty-one patients (31%) have required no therapy, and remain relatively stable with a median follow- up period of 50 months. Treatment was required at either diagnosis (36 patients) or at subsequent follow-up (11 patients). Initial response rates were similar in patients treated with cyclophosphamide (CTX) with or without prednisone (69%), or prednisone alone (73%). Overall, 61 patients (90%) are alive with a median follow-up of 44 months. Actuarial median survival of this entire cohort is 161 months. The presence of anemia or symptoms does not appear to correlate with the tumor burden. In patients requiring therapy, a lower ANC and the presence of B-symptoms/infection were independently associated with a significantly lower probability of achieving a molecular or hematologic complete remission (H-CR). Intermittent immunosuppressive therapy is effective in achieving durable responses in a number of patients. T-LGL proliferations are associated with a favorable prognosis and response to therapy. However, significant heterogeneity exists in clinical presentation and associated comorbid conditions. These disorders should be included in the differential diagnosis of patients with unexplained cytopenias, particularly in the setting of RA and other autoimmune disorders. Analogous to the situation with monoclonal gammopathies, a term such as T-cell clonopathy of undetermined significance (TCUS) may be more appropriate to describe these patients.