Effect of therapy on T cell subpopulations in patients with chronic lymphocytic leukemia

Delayed onset of autoimmune hemolytic anemia complicating cladribine therapy for Waldenström macroglobulinemia

Therapeutic options for patients with Waldenström macroglobulinemia (WM) now include the purine nucleoside analogues, fludarabine and cladribine. Both these agents have been associated with the onset of severe life-threatening autoimmune hemolytic anemia (AIHA) in patients with chronic lymphocytic leukemia (CLL). In these reports, AIHA developed within 6 weeks of drug administration and was generally resistant to conventional therapy. AIHA following purine analogues has not been reported in other hematologic malignancies. We report here on 4 patients with WM who developed AIHA following cladribine therapy. Cladribine was administered as a 2-hour infusion at a dose of 0.12 mg/kg per day for 5 consecutive days, at 28-day intervals. The median number of cycles was four (range, 4 to 6). AIHA occurred at a median of 40 months (range, 24 to 60) from cladribine administration. Only 1 patient responded to oral steroids while the other 3 were resistant to multiple therapeutic interventions. Two patients, 1 in complete remission and 1 requiring transfusional support, remain alive, and 2 have died. In contrast to published reports of the early onset of AIHA occurring after purine analogues in CLL patients, we observed AIHA in WM patients as a delayed event.

Opportunistic pulmonary infections with fludarabine in previously treated patients with low-grade lymphoid malignancies: a role for Pneumocystis carinii pneumonia prophylaxis

The high incidence of opportunistic pulmonary infections in fludarabine-treated patients at Walter Reed Army Medical Center (WRAMC) and in the literature are described. A CancerLit search of fludarabine from June 1983-April 1994 with subsequent cross referencing and a retrospective review of all patients receiving fludarabine at WRAMC was performed. A total of 2,269 patients with low-grade lymphoid malignancies who received 7,547 + cycles of fludarabine were identified from the literature. Seventy-three (3.2%) of these patients developed opportunistic infections. Seventy-one (97%) of these infections occurred in patients who were pretreated with alkylator regimens or corticosteroids. Forty-five (2%) of these were of respiratory origin and associated with a 56% mortality rate. In contrast, 6 of the 21 patients (29%) treated with fludarabine at WRAMC developed opportunistic pulmonary infections which included three Pneumocystis carinii (PCP), one PCP/disseminated Candidiasis, one Mycobacterium avium intracellulare, and one Aspergillus niger pneumonia. These infections developed during and after treatment with fludarabine in alkylator-resistant patients who had received corticosteroids before (n = 6), during (n = 1), or after (n = 4) fludarabine therapy. Lack of PCP prophylaxis was the only significant (P = .018) variable that differentiated patients who developed opportunistic pulmonary infections. Corticosteroid treatment before, during, or after fludarabine treatment in patients with alkylator-resistant, low-grade lymphoid malignancies who have not received PCP prophylaxis is associated with an increased risk of opportunistic pulmonary infections. Aggressive work-up of pulmonary syndromes and PCP prophylaxis in these patients should be considered during and after treatment with fludarabine.

Infections in chronic lymphocytic leukemia: risk factors, and impact on survival, and treatment

Patients with chronic lymphocytic leukemia (CLL) are at an increasing risk of infectious morbidity and mortality. Infections are generally due to bacteria and influenced by the degree of hypogammaglobulinemia; although, in more advanced stages of disease they may also be contributed by neutropenia due to bone marrow infiltration and/or cytotoxic therapy. Furthermore, defect in cell-mediated immunity appears to be a predisposing factor to infections in patients treated with newer purine analogues. Controversies surrounding the pathogenesis of infectious complications in CLL raise several questions on their management. Patients with advanced disease who receive cytotoxic therapy might qualify for antibacterial prophylaxis. Intravenous immunoglobulin (IVIG), although of scientific interest, may be of little relevance at the present time. The new growth factors should be tested in well-designed prospective studies.

A study of splenic irradiation in chronic lymphocytic leukemia

A retrospective study was performed to assess the effect of splenic irradiation (SI) on splenomegaly, splenic pain, anemia, and thrombocytopenia in patients with chronic lymphocytic leukemia. Twenty-two patients received 32 courses of SI. Of 31 courses of SI given for splenomegaly there were 19 responders (61%). Ten courses of SI were given for splenic pain resulting in partial relief of pain in 4 courses and complete relief in 4 courses. Only 4 of 16 courses given for anemia resulted in elevations of hemaglobin of 2 g/dL or more. Of the 14 courses of SI given for thrombocytopenia there were only 2 responses with platelet counts decreasing further in another 9 courses. The median duration of response was 14 months (range: 3-116 months). There was no dose-response relationship detected for SI in CLL. Treatment related toxicity was hematologic and secondary to leucopenia and thrombocytopenia. We recommend the use of small fraction sizes of 25 cGy to 50 cGy and close monitoring of hematological parameters. Splenic irradiation effectively palliates splenomegaly and reduces spleen size in CLL. It was of limited value in correcting anemia and thrombocytopenia in this patient population.

Splenic irradiation in chronic lymphocytic leukemia. A 10-year experience at a single institution

A group of 38 patients with a median age of 70 years and chronic lymphocytic leukemia (CLL) were treated using a cobalt 60 U or a 6-MeV linear accelerator. A direct field or two opposite fields covered the palpable spleen area in most patients. 100 cGy were administered weekly for a total dose of 10 Gy, given over 10 weeks. The stage arrangement (according to Rai) for the 32 evaluable patients was as follows: Stage I: 11 patients, Stage II: nine patients, Stage III: three patients, and Stage IV: nine patients. Patients in Stages I and II were treated when symptomatic. Twenty-five patients (78%) achieved hematologic response (HR), defined as normalization of the differential leukocyte count, of the total blood cell count, and of bone marrow infiltration. However, no complete response according to the standard criteria of response has been obtained. The median response time of HR was 7 months (range, 1.5 months to greater than 120 months). The overall median survival time from the start of splenic irradiation (SI) was 40 months. More than 50% splenomegaly reduction was obtained in 63% of patients, whereas no benefit was verified in the lymphadenopathy. The incidence of second tumor was 29%. Fourteen patients benefited from a further 21 SI cycles. SI does not result in a complete remission and therefore cannot modify the course of CLL. This treatment is most advisable for elderly patients with predominant bone marrow lymphocytosis, for patients with previous extensive chemotherapy or radiotherapy, and for patients with poor marrow reserve. Moreover, because of the absence of toxicity subsequent treatment is not compromised.

The intrinsic radiosensitivity of lymphocytes in chronic lymphocytic leukaemia, quantitatively determined independently of cell death rate factors

Survival curve shape for lymphocytes X-irradiated in vitro is governed by death rate as well as intrinsic radiosensitivity. We have resolved into these two components the survival curves obtained for CLL lymphocytes by use of a simple mathematical model. A multiple correlation coefficient comparing the predicted with the experimental survival curves was close to unity (0.954-0.999). For 14/18 patients with unequivocal B-cell CLL, the leukaemic (colchicine ultrasensitive) cells behaved as a homogeneous population (D37 0.32-1.28 Gy). This is similar to the more radiosensitive class of lymphocytes of normal blood (believed to include the B cells) and is some 4-fold less than the more radioresistant class (comprising most of the T cells). The lethally hit cells were homogeneous in death rate, which followed first order kinetics. The half-life (range 9-87 h) was, on average, some 50 per cent shorter than the more radiosensitive normal lymphocytes. The remaining four patients constituted a miscellaneous group. From one of these, it can be seen that an excessively slow death rate can give the misleading impression of radioresistance. It is hypothesized that the benefit afforded certain CLL patients treated with low-dose total body irradiation (TBI) or splenic irradiation (SI) may reside, partly, in the sparing of T lymphocytes of the helper type and in accompanying selective elimination (or functional inactivation) of those of the suppressor type.

The possible role of radiotherapy in chronic lymphocytic leukaemia: a critical review

The few clinical studies which have utilized irradiation as a treatment modality for chronic lymphocytic leukaemia (CLL) during the last two decades have led to rather conflicting and sometimes disappointing results. Low-dose total body irradiation (TBI) and extracorporeal, or mediastinal, radiotherapy did not appear to be superior to chemotherapy in most trials. Only the fractionated low-dose (600-800 rad) splenic irradiation was found to induce a long-lasting decrease of the lymphocyte count and a decrease in bone marrow infiltration in a significant proportion of cases, without any noticeable haematological toxicity. But new data is recently emerging; stratification of CLL in various subgroups, better understanding of the role of the normal T-cell subsets, better knowledge of the interaction between irradiation and haematopoiesis, and of the radiosensitivity of the various lymphocyte subpopulations. Thus one can now reconsider the possible role radiotherapy, and particularly splenic irradiation, can play as an alternative treatment to chemotherapy for CLL. Haematological toxicity is still limiting the use of TBI. The spleen irradiation avoids this drawback. Recent data suggest that this splenic irradiation could be efficient by means of several mechanisms; the successive destruction, fraction after fraction, of the part of the malignant lymphocyte clone present in the spleen is likely to be the main therapeutic explanation, with the knowledge that the lower the differentiation of the malignant clone, the more efficacious the irradiation. But in parallel, the destruction of the large subset of T-suppressors which is constantly present in the spleen may account for the improvement of the peripheral blood count after splenic irradiation, and possibly for a direct effect towards the malignant clone. With respect to these new data, splenic irradiation clearly needs further clinical evaluation in the treatment of CLL.

Interferon-induced aplasia: evidence for T-cell-mediated suppression of hematopoiesis and recovery after treatment with horse antihuman thymocyte globulin

A severe and persistent pancytopenia occurred in a 42-year-old woman with a non-Hodgkin's lymphoma following a 10-day course of intramuscular human leukocyte alpha interferon (IFN, 9.0 IU/day). Within 2 weeks of IFN, marrow nucleated myeloid and erythroid precursor cells and megakaryocytes were nearly absent and marrow progenitor cells (CFU-E, BFU-E, CFU-GM) were undetectable. Analysis of marrow lymphocytes revealed that nearly 50% of the cells were E-rosette+, T gamma+, OKT8+ (suppressor/cytotoxic) T-and/or Leu 7+ natural killer (NK) lymphocytes and 50% were IgM Kappa, B1+, B-lymphocytes. In vitro erythroid culture studies were consistent with T-cell-mediated suppression of erythropoiesis. After 2 months without improvement on corticosteroid/androgen therapy, a 10-day course of intravenous antithymocyte globulin (ATG) was administered. This was followed by a prompt reticulocytosis and a rise in blood neutrophils. After ATG therapy, there was a sixfold reduction in marrow suppressor cells, loss of in vitro suppressor effects on erythroid progenitor cells, and complete reversal of blood and marrow OKT4/OKT8 (helper/suppressor) ratios. These studies suggest that interferon may suppress hematopoiesis in some patients by activating marrow suppressor T- and/or NK cells. Treatment aimed at reduction of marrow suppressor cells may aid in hematologic recovery without eliminating the infiltrating lymphoma.

Lymphocytic lymphoma/B-chronic lymphocytic leukaemia--an immunohistopathological study of peripheral B lymphocyte neoplasia

Twenty seven patients with malignant lymphoma of lymphocytic type/B-chronic lymphocytic leukaemia (ML, L/B-CLL, Kiel classification) diagnosed from lymph node and splenectomy specimens were studied histologically and immunologically. Lymph node biopsies showed a diffuse effacement of normal architecture by small round lymphocytes usually with scattered proliferation centres (PC). A1 spleens showed white pulp with or without red pulp involvement, sometimes with tumour nodules present. PC-like cells or PC were only found in the white pulp or tumour nodules. Studies of 13 specimens using the ABC immunoperoxidase technique on frozen sections with a large panel of monoclonal antibodies showed that although a part of the monoclonal B cell neoplasm, the proliferation centres or splenic white pulp have a different phenotype from the surrounding cells. Some of these phenotypic changes are similar to those reported with in vitro induction of "maturation" of ML, L/B-CLL cells. The implications for normal B-cell development are discussed. In contrast to reported peripheral blood findings, T cells, predominantly of T helper phenotype in lymph nodes, were present but usually not numerous.