Significant Variability in the Identification and Reporting of Band Neutrophils by Participants Enrolled in the College of American Pathologists Proficiency Testing Program: Time for a Change

CONTEXT.—

Increased band neutrophils in blood smear differential counts ("bandemia") are entrenched in medicine as a flag for sepsis. However, laboratory hematology experts have long advocated for discontinuation of reporting bands separately from segmented neutrophils because of poor sensitivity and specificity, poor interobserver agreement, and availability of alternative biomarkers for sepsis.

OBJECTIVE.—

To describe band neutrophil reporting practices and reproducibility of band classification among laboratories participating in the College of American Pathologists (CAP) proficiency testing (PT) program.

DESIGN.—

A survey questionnaire was distributed to hematology PT participants. A subsequent morphologic challenge included 12 preselected cell identifications of segmented neutrophils, bands, and metamyelocytes, and a 100-cell manual differential count of a digitally scanned blood smear.

RESULTS.—

Among laboratories that reported manual differentials, most respondents reported bands (4554 of 5268; 86.4%). Only 3222 of 4412 respondents (73.0%) provided band reference ranges. Though participants classified "easy" band neutrophils well (78.0%-98.3%), categorization of cell identifications for "moderate" and "difficult" bands was poor (3.1%-39.0% of laboratories), with classification instead as segmented neutrophils. This pattern was seen regardless of laboratory demographic characteristics. Marked variability in band counts was observed on the 100-cell differential count for both CAP PT participants and CAP Hematology and Clinical Microscopy Committee (HCMC) members (coefficients of variation, 55.8% and 32.9%, respectively). Variability was significantly improved when segmented and band neutrophils were grouped together (coefficients of variation, 6.2% and 5.0%, respectively).

CONCLUSIONS.—

Most CAP PT-participating laboratories report band counts, many without reference ranges. The survey confirms significant interlaboratory variability of band enumeration when bands are separately identified from segmented neutrophils. This study reaffirms the CAP Hematology and Clinical Microscopy Committee's strong recommendation to group segmented and band neutrophils together in manual differential counts.

Abstract LB-228: Resistance to BRAF inhibition in BRAF V600E colorectal cancer is associated with PI3K/AKT activation and hypermethylation

BRAF V600E mutation has been detected in approximately 8% of metastatic colorectal cancers (CRC) and results in constitutive activation of BRAF and the downstream MEK-ERK1/2 pathway. PLX4032, a selective inhibitor of BRAF V600E, has shown meaningful activity in melanoma (greater than 70% response) but only modest activity in BRAF V600E CRC (5%). The resistance of BRAF V600E CRC to BRAF inhibitors has been poorly understood. To explore these differences, BRAF V600E CRC cell lines were compared to BRAF V600E melanoma cell lines by reverse-phase proteomic array, which demonstrated higher levels of phospho-AKT and associated downstream pathway activation in CRC cell lines. Both colorectal cancer cells inherently resistant to PLX4720, an analog of PLX4032, and resistant subclones that were derived from BRAF V600E positive cells, showed increased expression of phospho-AKT and phospho-GSK3β, despite the sustained ability of PLX4720 to effectively inhibit MEK signaling. Silencing of PTEN, which in turn induced AKT activation, desensitized cells to the BRAF inhibitor. Furthermore, combined treatment of PLX4720 with two different PI3K inhibitors, LY294002 and GDC-0941, synergistically inhibited growth in a panel of BRAF V600E cells through both apoptosis and G1 phase arrest. It has been previously shown that BRAF V600E colorectal cancers are commonly associated with the CpG island methylation phenotype (CIMP), which is associated with epigenetically diminished PTEN expression. Combination treatment with the demethylating agent azacitadine and PLX4032 was also synergistic in cell lines with intact but suppressed PTEN, and was associated with PTEN re-expression. This was not seen in non-CIMP or PTEN BRAF V600E cell lines. Thus, colorectal cancer cells appear to escape BRAF targeting through a mechanism of increased PI3K/AKT activity, providing evidence to support investigation of new combination therapies with PI3K/AKT pathway inhibitors or demethylating agents.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-228. doi:10.1158/1538-7445.AM2011-LB-228

Development of hairy cell leukemia in a patient after cardiac transplantation

Post-transplant lymphoproliferative disorders (PTLDs) are well-recognized complications of bone marrow and solid organ transplantation, comprising a heterogenous group of lymphoproliferations with a spectrum of morphologic, phenotypic and molecular features. Although PTLDs are usually Epstein-Barr virus-driven B-cell lymphoproliferations, T/natural killer-cell lymphoproliferations, multiple myeloma, and Hodgkin's lymphoma are also recognized as part of the PTLD spectrum. Hairy cell leukemia, a low-grade B-cell lymphoproliferation, has not been recognized as part of the PTLD spectrum. We report the first case of hairy cell leukemia occurring after cardiac transplantation. It is unclear whether this case, similar to other cases of low-grade B-cell lymphoproliferations reported after transplantation, is related to immunosuppression and therefore part of the spectrum of PTLDs, or merely represents coincidental event occurring in an immunocompromised patient.

Expression of inhibitory receptor ILT3 on neoplastic B cells is associated with lymphoid tissue involvement in chronic lymphocytic leukemia

T cell responses against leukemia-associated antigens have been reported in chronic lymphocytic leukemia (CLL). However, the relentless accumulation of CLL B cells in some patients indicates that anti-tumor immune responses are inefficient. Inhibitory receptors from the Ig-like transcript (ILT) family, such as ILT3 and ILT4, are crucial to the tolerogenic activity of antigen presenting cells. In this study, we examined the expression of ILT3 on CD5+ B cells obtained from 47 patients with CLL. Using flow cytometry and RT-PCR, we found that B CLL cells from 23 of 47 patients expressed ILT3 protein and mature ILT3 mRNA. ILT3 protein and mRNA were not found in normal B cells obtained from donors without CLL. Expression of ILT4 in normal and B CLL cells showed a pattern similar to ILT3. The frequency of ILT3 positive CLL B cells was higher in patients with lymphoid tissue involvement, suggesting that ILT3 may have prognostic value in CLL. Our findings indicate that expression of ILT3 and ILT4 on CLL B cells represents a phenotypic abnormality that may play a role in tolerization of tumor-specific T cells.

The clinicopathologic spectrum of posttransplantation lymphoproliferative disorders

CONTEXT

Posttransplantation lymphoproliferative disorders (PTLDs) are a heterogeneous group of lymphoid proliferations occurring in the setting of solid organ or bone marrow transplantation. They show a clinical, morphologic, and molecular genetic spectrum ranging from reactive polyclonal lesions to frank lymphomas. The close association with Epstein-Barr virus has been established and the pathogenetic role of this virus is becoming better understood. Although they are relatively uncommon, PTLDs are a significant cause of morbidity and mortality in transplant patients.

OBJECTIVE

To review the incidence, risk factors, clinical features, pathogenesis, and classification of PTLDs.

DATA SOURCES

We reviewed relevant articles indexed in PubMed (National Library of Medicine), with emphasis on more recent studies. The classification of PTLDs is based on the most current World Health Organization classification text.

CONCLUSIONS

Posttransplantation lymphoproliferative disorders are a heterogeneous group of disorders showing a wide clinical and morphologic spectrum. Although relatively uncommon, PTLDs represent a serious complication after transplantation. Many risk factors for PTLD are well established, including transplanted organ, age at transplant, and Epstein-Barr virus seronegativity at transplant. However, other factors have been implicated and still require additional examination. Recent studies are shedding some light on the pathogenesis of PTLDs and defining relevant pathways related to Epstein-Barr virus. As the pathogenesis of PTLDs is further elucidated, the classification of PTLDs will most likely evolve.

The clinicopathologic spectrum of posttransplantation lymphoproliferative disorders

CONTEXT

Posttransplantation lymphoproliferative disorders (PTLDs) are a heterogeneous group of lymphoid proliferations occurring in the setting of solid organ or bone marrow transplantation. They show a clinical, morphologic, and molecular genetic spectrum ranging from reactive polyclonal lesions to frank lymphomas. The close association with Epstein-Barr virus has been established and the pathogenetic role of this virus is becoming better understood. Although they are relatively uncommon, PTLDs are a significant cause of morbidity and mortality in transplant patients.

OBJECTIVE

To review the incidence, risk factors, clinical features, pathogenesis, and classification of PTLDs.

DATA SOURCES

We reviewed relevant articles indexed in PubMed (National Library of Medicine), with emphasis on more recent studies. The classification of PTLDs is based on the most current World Health Organization classification text.

CONCLUSIONS

Posttransplantation lymphoproliferative disorders are a heterogeneous group of disorders showing a wide clinical and morphologic spectrum. Although relatively uncommon, PTLDs represent a serious complication after transplantation. Many risk factors for PTLD are well established, including transplanted organ, age at transplant, and Epstein-Barr virus seronegativity at transplant. However, other factors have been implicated and still require additional examination. Recent studies are shedding some light on the pathogenesis of PTLDs and defining relevant pathways related to Epstein-Barr virus. As the pathogenesis of PTLDs is further elucidated, the classification of PTLDs will most likely evolve.

Pediatric ALK+ anaplastic large cell lymphoma with t(3;8)(q26.2;q24) translocation and c-myc rearrangement terminating in a leukemic phase

Pediatric ALK-positive anaplastic large cell lymphoma (ALK+ ALCL) is usually associated with a favorable prognosis. ALK+ ALCL associated with a leukemic phase is uncommon, but has been associated with an aggressive clinical course and unfavorable prognosis. Overexpression of c-myc has been shown to be a consistent finding in ALK+, but not ALK-negative ALCL (ALK- ALCL), and the c-myc gene is considered a downstream target of deregulated ALK signaling. We describe a pediatric ALK+ ALCL with a leukemic phase at relapse. Similar to other rare cases described in the literature, it followed an aggressive clinical course despite multiple regimens of chemotherapy and bone marrow transplantation. Lymphoma cells showed aberrant ALK expression and c-myc overexpression. In addition to the characteristic t(2;5)(p23;q35) translocation, a t(3;8)(q26.2;q24) translocation was also present, and c-myc gene rearrangement was confirmed by FISH analysis. The findings in this case demonstrate the association of peripheral blood leukemic involvement and aggressive clinical course, and suggest that other factors, such as c-myc rearrangement, may be responsible for the aggressive clinical behavior in ALK+ ALCL.

[A synthesis of cinnamoyloxyisoflavones]

Interaction of 7-hydroxyisoflavonones with cinnamoyl chloride results in cinnamoyloxyisoflavonones.

Characterizing CD43 expression in haematogones using multicolor flow cytometric analysis

Haematogones are precursor B cells commonly detected in small numbers in the bone marrow. Morphologically, haematogones can mimic lymphoblasts and are best distinguished using multicolour flow cytometry with antibody combinations. Haematogones show characteristic and reproducible patterns of antigen expression representing the B-cell maturation sequence. CD43 expression, widely seen in haematopoietic elements, has not been well characterized in haematogones. We demonstrate that CD43 is consistently expressed in haematogones in a reproducible pattern similar to that of CD10 when combined with CD20. We propose that in combination with other markers, CD43 can be useful in the identification of haematogones.

T-cell post-transplantation lymphoproliferative disorders after cardiac transplantation: a single institutional experience

Post-transplantation lymphoproliferative disorders (PTLDs) are a well-recognized and potentially life-threatening complication of solid organ transplantation. While the vast majority of PTLDs are B-cell lymphoproliferations, T-cell PTLDs are rarely seen. Among 898 patients receiving cardiac transplants between 1990 and 2003, 34 patients (3.8%) developed PTLDs with two (0.2%) T-cell PTLDs, 31 (3.5%) B-cell PTLDs and one (0.1%) natural killer cell PTLD. An additional three cases of T-cell PTLD were identified among all cardiac transplant patients followed at our institution. These T-cell PTLDs comprised a heterogeneous group of Epstein-Barr virus negative lymphoproliferations that developed late after transplantation and followed an aggressive course.

Mature B-cell acute lymphoblastic leukemia with t(9;11) translocation: a distinct subset of B-cell acute lymphoblastic leukemia

Mature B-cell acute lymphoblastic leukemia (ALL) is typically associated with the FAB-L3 morphology and rearrangement of the MYC gene, features characteristic of the leukemic phase of Burkitt's lymphoma. However, the term 'mature' has also been used to describe other rare cases of B-ALL with light-chain surface immunoglobulin expression. In contrast, infantile B-cell ALL is generally characterized by rearrangement of the MLL gene, an immature pro-B-cell phenotype, and CD10 negativity. We describe two unusual cases of infantile B-ALL with non-L3 morphology, expressing a mature B-cell phenotype (lambda sIg+, CD19+, CD10-, TdT-, and CD34-), and showing MLL rearrangement without MYC rearrangement at presentation. Both infants relapsed after months of morphologic and genetic remission. At relapse, the t(9;11) translocation was detected in both cases by spectral karyotyping. After the initial relapse, both cases followed a rapid and aggressive course. Literature search identified few similar cases, all expressed lambda surface immunoglobulin and showed MLL rearrangement (majority with the t(9;11) translocation). These cases show that B-ALL with MLL rearrangement, especially the t(9;11) translocation, can express a 'mature' B-cell phenotype and may represent a distinct subset. Identification of additional cases will further clarify the significance of MLL rearrangements in mature B-ALL.

EBV-associated, extranodal NK-cell lymphoma, nasal type of the breast, after heart transplantation

Post-transplantation lymphoproliferative disorders (PTLDs) are predominantly Epstein-Barr virus (EBV)-associated B-cell lymphoproliferations. PTLDs of T-cell lineage are rare, mostly reported after renal transplantation and show less frequent association with EBV. NK-cell lymphomas after transplantation (NK-cell PTLDs) are very rare; only five cases are reported so far in the English literature, all developed after renal transplantation. We describe a case of EBV-associated, extranodal NK-cell lymphoma of nasal type, involving the breast in a cardiac allograft recipient 5 years after transplantation. The neoplastic cells are positive for CD2, cytoplasmic CD3, CD7, CD43, CD56, TIA-1 and p53; and negative for surface CD3 and CD57. Analysis of T-cell receptor beta and gamma genes fails to show clonal rearrangement. EBV studies show clonal episomal integration of EBV and latency II pattern (EBER-1+, LMP-1+, EBNA-1+, EBNA-2-). In conclusion, NK-cell PTLDs are rare complications that arise relatively late after solid organ transplantation, show strong association with EBV, and can follow an aggressive clinical course. To the best of our knowledge, we present the first reported case of NK-cell PTLD after cardiac transplantation and the unifying clinical and diagnostic features of NK-cell PTLDs occurring after solid organ transplantation.

International trends and patterns of primary liver cancer

Primary liver cancer (PLC) is common in many areas of the developing world, but uncommon in most of the developed world. Some evidence suggests, however, that the global pattern of PLC may be changing. To clarify this issue, we examined incidence rates for PLC over the 15-year time period, 1978-92, in selected cancer registries around the world. With some exceptions, developed countries have experienced PLC increases in incidence whereas developing countries have experienced declines. Although the reasons for the trends are not entirely clear, the increased seroprevalence of HCV in the developed world and the elimination of HBV-cofactors in the developing world are likely to have contributed to the patterns. Further progress against PLC may be seen in the developing world once the HBV-vaccinated segment of the population reaches adulthood. Published 2001 Wiley-Liss, Inc.

International trends and patterns of prostate cancer incidence and mortality

Prostate cancer is the most commonly diagnosed cancer in western men, and incidence is rising rapidly in most countries, including low-risk populations. Age-adjusted incidence and mortality rates from 15 and 13 countries between 1973-77 and 1988-92, respectively, were compared to provide leads for future analytic studies. Large increases in both incidence and mortality rates of prostate cancer were seen for all countries. For incidence, increases were more pronounced in the United States, Canada, Australia, France and the Asian countries, while the increases in medium-risk countries were moderate. Increases in incidence ranged from 25%-114%, 24%-55% and 15%-104% in high-, medium- and low-risk countries, respectively. Mortality rates rose more rapidly in Asian countries than in high-risk countries. Substantial differences in incidence and mortality across countries were evident, with U.S. blacks having rates that were 50-60 times higher than the rates in Shanghai, China. Increasing incidence rates in the United States and Canada are likely to be due in part to the widespread use of transurethral resection of the prostate and prostate-specific antigen testing, while increases in the Asian countries are probably related to westernization in these low-risk populations. The large disparities in incidence between high- and low-risk countries may be due to a combination of genetic and environmental factors. Future studies are needed to examine gene-gene and gene-environment interactions in various countries concurrently to shed light on the etiology of prostate cancer and to help elucidate reasons for the large differences in risk between populations.

A pitfall in using far-field bipolar electrograms in arrhythmia discrimination in a patient with an implantable cardioverter defibrillator

Analysis of stored electrograms from bipolar far-field electrodes is considered to be useful in differentiating supraventricular from ventricular arrhythmias. A case of inappropriate ICD shocks for sinus tachycardia is presented whereby successive shocks caused marked widening of the ventricular electrograms. Analysis of these stored electrograms, recorded from far-field bipolar electrodes, gave the false impression of ventricular tachycardia. The widening was due to the current of injury effects, probably a consequence of the large amount of intervening myocardium between the bipoles. While analyzing recordings from far-field bipolar electrodes is generally useful, it is not always reliable, for changes in electrogram morphology, relative to baseline rhythm, may result from other factors like current of injury.

SM-20 is a novel 40-kd protein whose expression in the arterial wall is restricted to smooth muscle

We have previously reported the identification of a novel cDNA, SM-20, whose corresponding mRNA levels are regulated by growth factors in rat aortic smooth muscle cell (SMC) culture. Affinity-purified polyclonal and monoclonal antibodies were made against a 230 amino acid region of the SM-20 putative peptide expressed in the bacterial vector, pET-3b. Western blot analyses of rat and human SMC lysates detected a single protein species of approximately 40 kd. SM-20 was not detected in concentrates of the culture medium. By immunohistochemistry, SM-20 was localized to filaments in the cytoplasm of cultured SMC. Like SM-20 mRNA, levels of SM-20 protein were increased 1-3 hours after serum stimulation of rat aortic SMC. In rat tissues, SM-20 antigen was detected in abundance in smooth, cardiac, and skeletal muscle. SM-20 was also detected in some epithelial cells of the kidney, pancreas, gastrointestinal tract, and skin, but was not found in the parenchyma of the liver, spleen, or testis. In the rat arterial wall, SM-20 antigen was restricted to the SMC of the media and, after balloon arterial injury, was found most abundantly in the neointima. In human atherosclerotic coronary arteries, SM-20 antigen predominated in the SMC of the intimal plaques and was not detected in macrophages, endothelium, or adventitial cells. Thus, SM-20 encodes a protein which serves as a novel SMC-specific marker within the vessel wall.