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E Vorst

Publications and source records attributed to E Vorst.

12 recordsLinked to original sources
PubMed1999

B-cell prolymphocytic leukemia: a survey of 35 patients emphasizing heterogeneity, prognostic factors and evidence for a group with an indolent course.

We report a retrospective survey of 35 patients (18 males and 17 females) with B-Prolymphocytic leukemia (B-PLL) followed for a median of 63 months. Twelve patients fulfilled Galton's original clinical and hematological criteria, presented with prominent splenomegaly and hyperleukocytosis and showed rapid progression soon after diagnosis. Twelve cases with gradually increasing spleen size and prolymphocyte count had an indolent course. Seven of this group are alive 68 to 164 months after diagnosis, whereas five died from causes unrelated to PLL. Eleven patients who never developed impressive leukocytosis had a variable prognosis. In the group of 17 patients treated with chlorambucil and prednisone (CP) or cyclophosphamide, vincristine, prednisone (COP) 8 achieved a partial remission (PR) with a median response of 32 months. In the group of six cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) treated patients one achieved a complete remission and two PR (median response was maintained for 30 months). Three patients treated with 2CdA achieved good PR. Six patients remained untreated. Median survival was 65 months and the probability of overall survival for 3, 5, and 10 years was 63%, 56% and 35%, respectively. Anemia < 11 g/dl and lymphocytosis > 100 x 10(9)/l were predictors of shorter survival in this group of patients. Age over 70, gender, B-symptoms at presentation, spleen size, thrombocytopenia, low IgG and complement levels, presence of paraproteinemia and the pattern of bone marrow infiltrate were not significant. Our findings show that all B-PLL may not have such a poor prognosis as described in earlier reports. The existence of prior symptoms evolving gradually after years to obvious PLL and cases with mild prolymphocytosis could possibly lead to underdiagnosis of the entity. Identification and follow-up of such cases may suggest a different natural history, variable prognostic features and different survival curves for B-PLL patients. In the light of the above, we suggest that the therapeutic approach for B-PLL should always relate to the severity of the disease.

Adult↗
PubMed1994

Verapamil inhibits B-cell proliferation and tumor necrosis factor release and induces a clinical response in B-cell chronic lymphocytic leukemia.

Four B-CLL patients, treated with verapamil for cardiac problems, showed substantial reduction of lymphadenopathy in one, a 3- and 5-year stabilization of B-CLL in two patients, and a dramatic decrease in lymphocyte count, lymphadenopathy and splenomegaly in one stage IV patient. We therefore studied the effects of verapamil on B-CLL cells in vitro. In 13 samples we observed that verapamil strongly inhibited in vitro proliferation of pokeweed mitogen (PWM) stimulated and unstimulated cells. Using a cytotoxic bioassay, we found that verapamil markedly inhibited the spontaneous and PMW-induced release of tumor necrosis factor (TNF) by B-CLL cells. These findings suggest that verapamil may block B-CLL cell proliferation through inhibition of TNF release and thereby may contribute to the management of B-CLL.

Aged↗
PubMed1990

Further characterization of prolymphocytic leukemia cells as a tumor of activated B cells.

Peripheral blood mononuclear cells from 24 patients with prolymphocytic leukemia (PLL) were isolated using a Ficoll-Hypaque gradient and stained by indirect immunofluorescence using a wide panel of monoclonal antibodies against B cell restricted and associated antigens, including HLA DR (Ia), CD19, CD21 (C3dR) surface membrane immunoglobulin (Slg), CD10 (CALLA), C3b, B5, CD25 (TAC), PCA1, T9, and T10. The cells were also tested for the FMC7, defined previously on PLL cells and the RAB1, a newly described hairy cell leukemia antigen. Thirteen out of the 24 samples expressed with variable intensity all the above antigens. While Ia, CD19, CD20, FMC7, and RAB1 were strongly or moderately expressed in all, the complement receptors (CD21 and C3b) were only weakly expressed in 12 cases; and the activation antigens B5, TAC, T9, T10, and PCA1 were found with variable intensity in two-thirds of the cases. In 50% of the cases tested, the CD5 antigen (usually strongly expressed on B CLL cells) was weakly to moderately expressed. These findings (absence or weak expression of complement receptors with variable expression of activation antigens) suggest that the PLL cells are activated B cells. When stimulated in vitro by anti-mu and TPA, (phorbol ester) tumor cells showed a decrease in CD21 and Slg and a stronger expression of CD25, T9, T10, and PCA1, with evidence of Ig secretion in four out of the seven cases studied. This confirms that the PLL cells arrested at an advanced stage of differentiation progressed narrowly to more differentiated cells. In view of our findings, we believe that the term prolymphocytic leukemia is inaccurate to define the stage of cell differentiation, and we suggest calling the disease preplasmacytic leukemia.

Antibodies, Monoclonal↗
PubMed1988

Gray platelet syndrome in the elderly.

A 68-year-old male who suffered from thrombocytopenia and mild splenomegaly for 18 years was found to present agranular gray platelets on peripheral blood smear. Bone biopsy revealed a mild, diffuse, reticular fibrosis with no collagen, and electron microscopy of the platelets showed an absence of almost all the alpha-granules. Platelet thrombospondin and fibronectin analysed by SDS-polyacrylamide gel electrophoresis and Rocket immunoelectrophoresis were absent. Follow-up of 4 years showed the same parameters with no evidence of active myeloproliferative or dysmyelopoietic disorders. Hemorrhagic diathesis was limited to ecchymoses and postprostatectomy bleeding, necessitating platelet transfusion. This led us to conclude that our patient probably had a constitutional primary alpha-granule deficiency or gray platelet syndrome. This extremely rare defect has been described in less than 10 patients, all of them very young. Our observation shows that these patients may have a long, uneventful survival.

Aged↗
PubMed1984

Platelet aggregation defect in megakaryoblastic leukemia.

Platelet aggregation induced in vitro with ADP, adrenalin and ristocetin was tested in 7 patients with megakaryoblastic leukemia (MKL). All patients had normal or high platelet counts and presented with hemorrhagic diathesis including purpura ecchymosis and epistaxis. Platelet morphology was grossly abnormal and electron microscopy revealed few, or absence of, alpha-granules. Platelet aggregation was reduced in all the cases with at least one aggregating agent. Our studies confirm that MKL is often accompanied by a thrombocytopathy which should be taken into account in the management of these patients.

Aged↗
PubMed1983

Bone marrow iron depression in competitive distance runners.

Suboptimal hemoglobin and serum iron have been reported in endurance athletes. In the present study peripheral blood, bone marrow cellularity and hemosiderin, serum iron and serum iron binding capacity were observed in 12 competitive distance runners. Hemoglobin, hematocrit, mean corpuscular volume and concentration, serum iron and iron binding capacity were within normal range. Peripheral blood showed mild hypochromia in six runners, bone marrow cellularity was reduced in two, while bone marrow hemosiderin granules were absent in seven and traces were seen in five. These data suggest that a proportion of highly trained distance runners have insufficient iron stores and need supplementation to balance their iron requirements.

Adolescent↗
PubMed1983

IgM lambda globular cytoplasmic inclusions in chronic lymphocytic leukaemia resembling immunocytoma.

In a 64-year-old female with chronic lymphocytic leukaemia, nearly 50% of the lymphocytes presented one or several globular intracytoplasmic inclusions resembling Russell bodies which were characterized by immunofluorescence as IgM lambda. On electron microscopy, the inclusions looked like cisternae of the rough endoplasmic reticulum. Surface membrane Ig was not detected and the serum IgM was low. The histology of a lymph node showed a lymphocytic proliferation with evidence of Ig synthesis, compatible with immunocytoma. The aggressive course of the disease necessitated polychemotherapy. This case represents an unusual ill-defined lymphoproliferative disorder, lying between the B-CLL and a non-secretory macroglobulinaemia.

Cytoplasm↗
PubMedDate not supplied

Carcinoma of pancreas associated with the 5q-syndrome.

A female patient with the 5q-syndrome (refractory macrocytic anemia with deletion of the long arm of No. 5 chromosome) was followed-up for a period of 33 months and developed a carcinoma of pancreas. Until death she showed no signs of leukemic transformation. This association has not been described, and the genetic predisposition of 5q-patients to malignancies is discussed.

Adenocarcinoma↗