Hematologic pathology最新文献

Two patients with acute nonlymphocytic leukemia (ANLL) and trisomy 4 as the only cytogenetic aberration are presented. Including the two, a total of 31 cases with this karyotype have been described till now. A review of the 31 cases shows that they fall into two distinct age groups, a younger group of 10 patients (5-34 years) and an older group of 21 patients (50-75 years). With four exceptions the diagnosis was ANLL in all cases, mostly FAB classes M2 and M4. At the time of diagnosis 18 had clinical signs of active infection. In 20 cases the peripheral leukocyte count was above 10 x 10(9)/L but not associated with presence/absence of infection. The median survival was 17 months from diagnosis. Independent prognostic factors were diagnosis (p = 0.01), peripheral leukocyte count (p = 0.03), and percentage of metaphases with trisomy 4 (p = 0.04). The two age groups as well as presence/absence of infection at the time of diagnosis were without significant prognostic consequences.

The chromosome 22 derivative, the Philadelphia (Ph) chromosome, results from the reciprocal translocation t(9;22) (q34;q11). On DNA level a BCR/ABL rearrangement involving the so-called major BCR (Mbcr) from chromosome 22 has been associated with chronic myeloid leukemia (CML). For Ph+ ALL a site of rearrangements in the 5' part of the BCR (breakpoint cluster region) gene on chromosome 22, the so-called minor bcr region (mbcr) has been described within the first intron in a 10.8 kb region (=bcr2 or m-BCR1). The BB1 probe detects two Eco fragments of 8.5 and/or 11 kb, which may appear as monomorphic or heteromorphic alleles, both covering bcr2. We have analyzed EcoRI restriction polymorphisms within bcr2 in 42 patients with a rearrangement in M-bcr (including 39 Philadelphia chromosome-positive (Ph+) CML patients and 3 ALLs) and in 18 healthy unrelated volunteers. Of the 42 patients tested, 52.4% (22) had the 8.5 kb bcr2 allele, 21.4% (9) had the 11 kb bcr2 allele, and 26.2% (11) had both the 8.5 and the 11 kb allele. In addition to normal allelic polymorphisms in bcr2, rRFs (rearranged bcr2 restriction fragments) were found in bcr2 as shown in 33% (14 of 42) of our patients. By contrast, no rRFs were found in 18 healthy volunteers. Our results indicate, that heterogeneous rearrangements in bcr2 may appear in addition to BCR/ABL rearrangements involving M-bcr in Ph+CML.

Two culture methods are available for the study of the blast cells of acute myeloblastic leukemia (AML); first, a minority of blast cells will form colonies in methylcellulose cultures in the presence of suitable growth factors. Second, clonogenic blast cells will increase in suspension cultures. Both methods can be used to assess the sensitivity of blasts to chemotherapeutic drugs, but different dose-response curves are obtained with each. Thus cytosine arabinoside (ara-C) is more toxic to clonogenic blasts in suspension than in methylcellulose, while for 5-azacytidine (5-aza) the reverse is seen. Arabinofuranosyl-5-Azacytosine (ara-AC) combines the chemical features of the two drugs. That is, its sugar moiety has the same diastereomeric change in the furanose ring as ara-C and its pyrimidine ring has the same substitution of nitrogen for carbon at the 5' position as 5-aza. We compared the sensitivity of AML blasts with ara-Ac in suspension and in methylcellulose. As a control, the same comparison was made for the sensitivities to ara-C. Blast cells were less sensitive to ara-AC than to ara-C under all conditions; but, ara-AC sensitivity was greater for cells in methylcellulose than for cells in suspension. Thus, AML blasts respond to ara-AC in culture with a pattern similar to that of 5-aza and opposite to that of ara-C. Since ara-C is a more useful drug in the treatment of AML than 5-aza, we interpret the culture results as predicting that ara-AC may not be effective in AML.

Evidence suggests that prognosis in patients with myelodysplastic syndromes (MDS) or acute myelogenous leukemia (AML) depends more on karyotype than on formal classification as either MDS or AML according to the French-American-British (FAB) system. We provide further evidence of overlap between these two entities, reporting 4 patients who presented with either inv(16) (p13q22), del(16) (q22), or t(8;21) despite an FAB diagnosis of MDS rather than the diagnosis of AML with which these abnormalities are generally associated. In 3 patients, disease was relatively long-standing (3-10 months) prior to diagnosis, suggesting that the association between MDS and these cytogenetic abnormalities may not merely reflect a transient phenomenon. Two patients with inv(16) and the MDS subtype refractory anemia with excess blasts in transformation (RAEB-t) received AML-type chemotherapy as did a patient with t(8;21) and RAEB-t. All entered CR paralleling the high CR rate seen in patients with AML and these abnormalities. Our data support the concept that MDS and AML may be different manifestations of the same disease.

The terminal phase of the megakaryocyte life span is characterized by the onset of apoptosis to form compact, denuded megakaryocyte nuclei (DMK) surrounded by a thin rim of cytoplasm. Increased numbers of DMK have been reported in patients with acquired immune deficiency syndrome (AIDS) and chronic myeloproliferative disorders. In this study the bone marrow biopsies of 20 patients with various FAB subtypes of myelodysplastic syndrome (MDS) were examined for the presence of DMK cells and semiquantified for marrow reticulin level. For all MDS subtypes, a 9% or greater incidence of DMK in the total megakaryocyte population of the bone marrow was associated with a significant deposit of reticulin in the marrow. Immunocytochemical staining for Factor VIII (Von Willebrand factor), showed the abnormal deposition of this megakaryocyte protein in the extravascular stroma around many of the DMK cells. These findings are consistent with a hypothesis for excess stromal reticulin based on the defective maturation and intramedullary death of large numbers of megakaryocytes. The number of DMK in the marrow biopsies of MDS patients may have prognostic significance.

A case of composite lymphoma consisting of an anaplastic large-cell Ki-1 lymphoma and a small-cell follicular lymphoma was found in the splenic hilar lymph node of a 66-year-old woman. The Ki-1 lymphoma showed monoclonal IgM-lambda and CD 20, CD 74, and CDw 75 antigens by immunostaining and CD 19, CD 20, CD 22, and lambda antigens by flow cytometry. The follicular lymphoma also showed monoclonal IgM-lambda, and CD 20 and CDw 75 antigens but not CD 74 and CD 30 (Ki-1) by immunostaining. Flow cytometric analysis of the follicular lymphoma component was not conclusive, as it was impossible to separate the neoplastic from the normal small B lymphocytes. Ki-1 lymphoma usually is seen in childhood and is mostly of T cell origin. It is, therefore, unusual to find Ki-1 antigen component in a composite lymphoma of B-cell origin in an adult. However, there has been evidence to suggest that B-cell Ki-1 lymphoma may be related to follicular lymphoma. Thus, our case may represent a follicular lymphoma transforming into a Ki-1 lymphoma. Immunogenotyping in this case revealed that the two components were probably of the same clonal origin, as they seemed to share the same light chain gene. The presence of rearrangement in the switch region of the IgH in our case without the actual occurrence of heavy chain switching may have triggered somatic recombination in the IgH complex. This series of events may have led to the transformation of a low-grade lymphoma into a high-grade lymphoma, accounting for the two morphologic patterns seen in our bimorphic lymphoma.

The Working Formulation (WF) for the classification of non-Hodgkin's lymphomas was shown to be reproducible and clinically relevant in the original study. However, it has not yet been tested by an NCI-supported cooperative clinical oncology group. As a result, the Hematopathology Subcommittee of the Eastern Cooperative Oncology Group (ECOG) undertook a retrospective study to compare concordance and practical utility between the WF and the Rappaport Classification (RC). Data indicate that with appropriate modifications to minimize unclassifiable lymphomas, the WF can be effectively utilized in cooperative clinical oncology groups.

In this study, a clinicopathologically and immunophenotypically diverse group of T-cell neoplasms were evaluated by one- and two-color flow cytometry and/or immunohistochemistry for the presence of eight antigens (T10, T9, IL2-R, EMA, HLA-DR, LeuM1, Ki-1, and LeuM5) which are expressed in a hierarchical manner by phytohemagglutinin (PHA)-activated benign T cells. We found that 70 of the 72 T-cell neoplasms (97%) expressed at least one of these eight T-cell activation-associated antigens (T-AAgs) and that the number and type of T-AAgs expressed by the neoplastic T cells varied according to the clinicopathologic category of T-cell neoplasia. All 5 T-cell lymphoblastic malignancies expressed T10 and T9; 2 also expressed LeuM1. Twelve of 14 (86%) T cell chronic lymphocytic leukemias (T-CLL) expressed two to four T-AAgs, most frequently T10 (86%) and HLA-DR (79%). The 26 cutaneous T-cell lymphomas (CTCL) expressed between 2 and 5 T-AAgs, most commonly T9 (92%) and HLA-DR (92%), and least often T10 (12%) and EMA (15%). Twenty-six of 27 (96%) peripheral T-cell lymphomas (PTCL) expressed more than 4 T-AAgs. Each of the T-AAgs were expressed by between 22% (LeuM5) and 85% (T9) of the PTCLs. Some T-AAgs were preferentially expressed by the PTCLs in association with other T-AAgs, such as EMA in association with IL2-R and Ki-1. In addition, LeuM5 was preferentially expressed by CD4- CD8+ T-cell neoplasms. However, only 19 of the 72 (26%) T-cell neoplasms (3/5 lymphoblastic malignancies, 3/14 CLLs, 0/26 CTCLs, 13/27 PTCLs) expressed T-AAg immunophenotypic profiles paralleling those expressed by normal peripheral blood T cells activated in vitro with PHA. These results suggest that T-AAg expression by neoplastic T cells does not often mirror the hierarchical order of expression by activated benign T cells, implying that neoplastic T cells do not usually represent the precise malignant counterpart of activated benign, normal T cells.