EUROPEAN STROKE PREVENTION STUDY 2: DIPYRIDAMOLE AND ACETYLSALICYLIC ACID IN THE SECONDARY PREVENTION OF STROKE

In 1988, an optimal antiplatelet regimen for secondary stroke prevention remained to be defined. We undertook a randomised, placebo-controlled, double-blind trial to investigate the safety and efficacy of low-dose acetylsalicylic acid (ASA), modified-release dipyridamole, and the two agents in combination. Patients with prior stroke or transient ischaemic attack (TIA) were randomised to treatment with ASA alone (50 mg daily), modified-release dipyridamole alone (400 mg daily), the two agents in a combined formulation, or placebo. Primary endpoints were stroke, death, and stroke or death. TIA and other vascular events were secondary endpoints. Patients were followed on treatment for two years. We concluded that dipyridamole, in a modified-release form, at a dose of 200 mg b.d. and ASA 25 mg b.d., have been shown to be equally effective in the secondary prevention of ischaemic stroke and TIA; that when co-prescribed, the protective effects are additive, the combination being significantly more effective than each agent prescribed singly; and that low-dose ASA does not eliminate the propensity for induced bleeding.     

Peripheral T cell lymphoma: immunologic and cell-kinetic observations associated with morphological progression

Peripheral T cell lymphomas (PTCLs) form a morphologically heterogeneous group of non-Hodgkin's lymphomas that are generally considered to have immunophenotypes associated with mature T cells, usually those of helper T cells. We now describe and correlate the clinical, morphological, immunologic, and cell-kinetic findings based on the evaluation of eight tissue samples obtained at various times from a 13-year-old girl with PTCL. The early morphological expressions of this patient's PTCL were those of diffuse mixed-cell lymphoma and focal large-cell lymphoma (LCL) evolving from the histologic picture of an atypical immune response (AIR). These morphological findings were associated with an immature T cell immunophenotype associated with cortical thymocytes--namely, sheep erythrocyte rosette (sER)+, T11+, Leu-2a+, Leu-3a+, HLA-DR+, OKT6-, OKT9+, OKT10+--and with cell-kinetic findings that showed no evidence of aneuploidy and few cells in S phase. Diffuse pleomorphic LCL developed, which was associated with further dedifferentiation of the neoplastic T cells to the immunophenotype sER-, T11+, Leu-2a-, Leu-3a-, HLA-DR+, OKT6-, OKT9+, OKT10- and with cell-kinetic findings that demonstrated a distinct aneuploid population and a dramatic increase in the percentage of cells in the S phase. The immunophenotype of the PTCL at the time of the patient's death was T11-, Leu-2a-, Leu-3a-, HLA-DR+, OKT6-, OKT9+, OKT10-, an immunophenotype indistinguishable from that of a non-B non-T cell lymphoma. The immunologic findings in this case also suggest that an AIR in some cases may represent a prelymphomatous state or may be a morphological expression of PTCL. These observations indicate that PTCLs may be characterized by rapidly changing clinical, morphological, immunologic, and cell kinetic findings which are best evaluated by multidisciplinary studies.     

Studies on levamisole--induced agranulocytosis

Widespread clinical trials of leavo-tetramisole (levamisole) as an immunopotentiating agent in rheumatoid arthritis, metastatic carcinoma, and immunodeficiency states have been complicated by agranulocytosis (AGC) in 2.5%-13% of patients. Other than a relationship with prolonged high dosage, very little is known regarding the pathogenesis of levamisole-induced AGC. Whereas leukoagglutination was negative, fluorochromatic microgranulocytotoxicity (GCY) tests were positive with serum from 10 of 10 acutely neutropenic patients. The antibody was IgM, reacted with 100% of unrelated granulocytes, but not with T or B lymphocytes. Some sera also reacted with monocytes and the myeloid cell line, K-562. Tests for antigen-antibody complexes or cold autoantibodies were negative. Although clinical evidence strongly suggests a haptene (drug) mechanism, in vitro mixing experiments were also negative. An alternative choice parallels the model of aldomet- induced Coombs'-positive hemolytic anemia. Finally, GCY first became positive 2-3 mo prior to the onset of AGC on two patients, suggesting the possibility of identifying those at risk well before the onset of neutropenia.     

Marrow transplantation for chronic myeloid leukemia: a randomized study comparing cyclophosphamide and total body irradiation with busulfan and cyclophosphamide

A prospective randomized study was conducted comparing two conditioning regimens for the treatment of patients with chronic myeloid leukemia in chronic phase by marrow transplantation from HLA identical siblings. Sixty-nine patients received 60 mg/kg of cyclophosphamide on each of 2 successive days followed by 6 fractions of total body irradiation each of 2.0 Gy (CY-TBI), and 73 patients received 16 mg/kg of busulfan delivered over 4 days followed by 60 mg/kg CY on each of 2 successive days (BU-CY). There was no significant difference between the CY-TBI and the BU-CY groups in the 3-year probabilities of survival (0.80 for both), relapse (0.13 for both), or event-free survival (CY-TBI, 0.68; BU-CY, 0.71) or in speed of engraftment or incidence of venocclusive disease of the liver. The 4-year probabilities of survival and event- free survival for patients transplanted within 1 year of diagnosis were 0.86 and 0.72, respectively, for each group. Significantly more patients in the CY-TBI group experienced major creatinine elevations. There was significantly more acute graft-versus-host disease in the CY- TBI group. Fever days, positive blood cultures, hospitalizations, and inpatient hospital days were significantly more common in the CY-TBI group than in the BU-CY group. In conclusion, the BU-CY regimen was better tolerated than, and associated with survival and relapse probabilities that compare favorably with, the CY-TBI regimen.     

Marrow harvesting from normal donors

The experience at a single institution in harvesting marrow for allogeneic transplantation on 1,270 occasions from 1,160 normal donors is presented in detail, together with an analysis of all the donor complications. Four donors were less than 2 years old, and the youngest was 6 1/2 months. No special difficulties were encountered with these young donors. Hospitalization time was three days or less for 99% of the procedures. Six donors had life-threatening complications; three of a cardiopulmonary and two of an infectious nature, and one cerebrovascular embolic episode. Significant operative site morbidity, usually transient neuropathies, occurred in ten procedures. Ten percent of the donations were associated with transient postoperative fever of unknown origin. Increasing donor age was associated with a reduction of the cellularity of the marrow harvest. The use of stored autologous blood permitted the avoidance of blood bank transfusion in 81% of males, 69% of females, and 50% of children. It was concluded that the procedure was associated with a very low risk of complication, but that the involvement of normal donors in such an operation justifies stringent monitoring.     

Transplantation of allogeneic peripheral blood stem cells mobilized by recombinant human granulocyte colony-stimulating factor [see comments]

Peripheral blood stem cells (PBSCs) are widely used in autologous transplantation because of ease of collection and rapid hematopoietic reconstitution. However, PBSCs have rarely been used for allogeneic transplantation because of concerns about donor toxicities from cytokine administration and the theoretical increased risk of graft- versus-host-disease (GVHD) from the large number of T cells infused. Eight patients with advanced malignancies received allogeneic PBSC transplants from genotypically HLA-identical sibling donors. All donors received 5 days of recombinant human granulocyte colony-stimulating factor (rhG-CSF; 16 micrograms/kg/day) subcutaneously and were leukapheresed for 2 days. After treatment of the patient with total body irradiation and cyclophosphamide (n = 7) or etoposide, thiotepa, and cyclophosphamide (n = 1), PBSCs were infused immediately after collection and without modification. All patients received cyclosporine and either methotrexate (n = 6) or prednisone (n = 2) for GVHD prophylaxis, rhG-CSF was well tolerated with mild bone pain requiring acetaminophen occurring in two donors. All patients engrafted and in seven hematopoietic recovery was rapid, with 500 neutrophils/microL achieved by day 18 and 20,000 platelets/microL by day 12. Complete donor engraftment was documented by Y chromosome analysis in all four sex-mismatched donor-recipient pairs tested and by DNA analysis in two sex-matched pairs. One patient died on day 18 of veno-occlusive disease of the liver with engraftment but before chromosome analysis could be performed (results are pending in 1 patient). A second patient died of fungal infection 78 days after transplant. Grade 2 acute GVHD occurred in two patients and grade 3 GVHD occurred in one patient. One patient is 301 days from transplant in remission with chronic GVHD; the remaining five patients are alive and disease free 67 to 112 days after transplantation. Preliminary results indicate that allogeneic PBSCs mobilized by rhG-CSF can provide rapid hematologic recovery without an appreciably greater incidence of acute GVHD than would be expected with marrow. Further follow-up is required to determine the incidence of chronic GVHD and any potential beneficial effects on relapse after transplant.