Acute myeloid leukaemia M0: haematological, immunophenotypic and cytogenetic characteristics and their prognostic significance: an analysis in 241 patients.

Haematological, immunophenotypic and cytogenetic characteristics were analysed in 241 patients with acute myeloid leukaemia (AML) M0, including 58 children. Children < 3 years and adults between 60 and 70 years of age were most frequently affected. Immunophenotyping showed a heterogeneous phenotype. Anti-myeloperoxidase was positive in about half of the patients. Cytogenetic data were available from 129 (54%) patients. A normal karyotype was found in only 24%. Most of the abnormalities were unbalanced and the chromosomes 5, 7, 8 and 11 were the most frequently affected. Survival data were available from 152 treated patients (63%). The median overall survival for all patients was 10 months, 20 months for children (n = 36), 10 months for the young adult group (n = 50) and 7 months for the elderly patients (n = 66) (P = 0.09). Karyotype was not a prognostic factor influencing survival. AML M0 shows the immunological characteristics of early progenitor cells, but the expression of the different markers and cytogenetic abnormalities is heterogeneous. The prognosis is poor compared with other de novo AML and similar to that of AML with multilineage dysplasia or AML following myelodysplastic syndromes.

Cyclophosphamide, doxorubicin, vincristine and prednisone chemotherapy and radiotherapy for stage I intermediate or high grade non-Hodgkin's lymphomas: results of a strategy that adapts radiotherapy dose to the response after chemotherapy.

BACKGROUND: A limited number cycles of cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherapy followed by involved field radiotherapy is the treatment of choice for Ann Arbor stage I intermediate or high grade non-Hodgkin's lymphomas (NHL). The optimal radiotherapy dose in this combined modality setting, resulting in maximal disease control with minimal toxicity is unknown. In this retrospective single-center study we evaluated the results of a combined modality treatment strategy that adapts the radiotherapy dose to the response after chemotherapy, and focus on the influence of radiotherapy dose on local control and survival. PATIENTS AND METHODS: One hundred and forty patients with NHL Ann Arbor stages I/IE of intermediate or high grade malignancy received four cycles of CHOP chemotherapy followed by involved field radiotherapy (IF-RT). The radiotherapy dose for patients in complete response (CR) after CHOP was either 26 or 40 Gy. Patients in partial response (PR) after CHOP always received 40 Gy. The influence of the radiotherapy dose on treatment outcome was evaluated for patients in CR at the end of treatment (n=128). RESULTS: CR rates after chemotherapy and after radiotherapy were 67 and 91%, respectively. Seventy-four of the patients in CR after CHOP received 26 Gy, 20 patients in CR after CHOP 40 Gy. All patients in PR after CHOP (n=34) received 40 Gy. The localization of relapse (within or outside the radiation field) did not differ between patients receiving 26 or 40 Gy. Overall survival (OS) at 5 years for patients in CR after CHOP who received 26 and 40 Gy and for patients in PR after CHOP but CR after 40 Gy IF-RT was 76, 100 and 75%, respectively, (P=0.16), disease free survival (DFS) at 5 years 69, 90 and 75%, respectively, (P=0.52). CONCLUSIONS: No statistically significant differences in patterns of relapse or survival were found between patients receiving 26 or 40 Gy IF-RT, however the number of events in all subgroups was small.

Platelet-bound immunogloblins before and after platelet transfusion: measurement of in vivo binding.

In routine tests to investigate immunological mechanisms as a cause for enhanced destruction of transfused platelets; serum from the patient is tested against a panel of donor lymphocytes and platelets to demonstrate the presence of antibodies against HLA or platelet specific antibodies. Here we describe a flow cytometric technique in which in vivo binding of immunoglobulins (Ig) is measured. By comparing the histograms of the platelet suspensions before and after transfusion, four different patterns were obtained: no Ig binding before and after transfusion (pattern 1), pre-existent Ig binding (patterns 2 and 3) or preferential Ig binding to the transfused platelets (pattern 4). This technique was tested in 164 random platelet transfusions and 34 HLA-matched platelet transfusions. A statistically significant association was found between pattern 1 and a negative result of the indirect platelet immunofluorescence test for the detection of antibodies in the serum taken before the transfusion studied or a good platelet recovery and between pattern 4 and a positive indirect platelet immunofluorescence test or a low platelet recovery.

Rearranged immunoglobulin light chain genes as minimal residual disease markers in intermediate- and high-grade malignant B cell non-Hodgkin's lymphoma.

Minimal residual disease (MRD) detection in B cell non-Hodgkin's lymphoma (NHL) patients has been shown to be possible using the rearranged heavy (IgH) chain gene as a tumor marker. To explore a second independent tumor marker, we used specific PCR primer sets to identify tumor-specific rearranged Ig light chain (IgL) genes. Rearranged IgL genes were amplified from lymphoma DNA by multiplex PCR using separate primer sets for the Igkappa and the Iglambda genes. They were considered to be of tumor origin if they were monoclonal, and if the same rearrangement was isolated from at least two independent PCR products. From 12 out of 13 intermediate- and high-grade malignant NHL, PCR products could be obtained with IgL specific primers. PCR products from five NHL were studied in detail by cloning and sequencing. The rearranged IgL genes showed 85-100% homology with their closest germ line counterparts. Intraclonal IgL sequence heterogeneity was studied in five lymphomas and detected in only one. Minimal disease was studied in three patients by PCR, followed by Southern hybridization of the PCR product with a lymphoma-specific oligonucleotide probe, which allowed for detection of lymphoma DNA following 1000-fold dilution. Blood samples from one patient, who is in long-term clinical remission, were negative for the lymphoma-specific rearranged Igkappa gene. In the second patient the rearranged Iglambda gene was detected during the first clinical remission, that was followed by a nodal relapse, but not during the second remission, that has been stable for almost 3 years now. The third patient was negative for the rearranged Iglambda gene in blood samples up to 102 months after diagnosis. Circulating lymphoma cells were detected in blood and bone marrow samples which were negative by morphological and immunological criteria. Our studies show that the rearranged IgL gene can be used as a second independent tumor marker in intermediate- and high-grade malignant NHL.

Detection of minimal disease using rearranged immunoglobulin heavy chain genes from intermediate- and high-grade malignant B cell non-Hodgkins lymphoma.

Rearranged immunoglobulin heavy chain (IgH) genes provide unique clonal markers for B cells. Since amplification of the rearranged gene by polymerase chain reaction (PCR) and demonstrating that the amplified sequence is indeed derived from tumor cells is more problematic in non-Hodgkin's lymphoma (NHL) than in other B cell malignancies, we used a comprehensive PCR primer set and formulated stringent selection criteria to identify tumor-specific rearranged IgH genes. Rearranged IgH genes amplified from lymphoma DNA were considered to be of tumor origin if they were monoclonal, and if the same rearrangement was amplified with at least two independent VH-specific primers. From 11 of 13 (85%) intermediate- and high-grade malignant NHL, IgH rearrangements were isolated. Intraclonal IgH sequence heterogeneity was studied in four lymphomas, and detected in two of them. PCR using a lymphoma-specific primer followed by Southern hybridization of PCR product with a specific probe allowed detection of lymphoma DNA after 10,000-fold dilution. Circulating lymphoma cells were detected in patient blood and bone marrow samples which were negative by morphological and immunological criteria. Thus, also in intermediate- and high-grade malignant lymphoma, sensitive minimal disease detection using the rearranged IgH gene as a marker appears feasible.