Detecting Multiple Driver Mutations in a Patient with Essential Thrombocythemia

BACKGROUND Three driver mutations have been identified in patients with essential thrombocythemia - JAK2 V617F, CALR, and MPL. Out of these, JAK2 V617F is mostly common. These mutations are thought to be mutually exclusive; therefore, the initial workup may not include the identification of all mutations separately. CASE REPORT We present a case of a 55-year-old woman who was referred to the hematology clinic for an elevated platelet count noted when she was hospitalized for a renal stone. The patient was asymptomatic. A workup was initiated for essential thrombocythemia, and she was tested for JAK2 V617F mutation using an allele-specific polymerase chain reaction (AS-PCR) test in peripheral blood, which came back positive. The variant allele frequency was 2%. She underwent a bone marrow biopsy, and next-generation sequencing (NGS) showed a CALR mutation. A 52 bp deletion-type mutation was detected in the CALR gene on exon 9, with a variant allele frequency of 7%. The NGS did not detect JAK2 mutation due to its low sensitivity. She was started on aspirin alone as she was less than 60 years old and had no history of thrombotic events. The patient has been following up with the hematology clinic for the last 2 years and has not had any thrombotic events. CONCLUSIONS We propose that in patients with a low JAK2 V617 allele variant, testing for other driver mutations should be performed. In our patient, JAK2 mutation could be clonal hematopoiesis of indeterminate potential; therefore, the dominant mutation (CALR) would determine the disease phenotype.

Histiocytic Disorder Mimicking a Brain Tumor: A Report of 2 Rare Cases

Case series

Patients: Male, 65-year-old • Female, 61-year-old

Final Diagnosis: Langerhans cell histiocytosis • Rosai-Dorfman disease

Symptoms: The patient with LHD presented with increasing memory loss, confusion, and depression • the patient with RDD presented with dizziness and confusion for three weeks and headaches for one day

Medication: —

Clinical Procedure: —

Specialty: Pathology

Cystathionine Gamma-Lyase Is Increased in Testicular Seminomas, Embryonal, and Yolk Sac Tumors

BACKGROUND

Testicular cancer constitutes 1.0% of male cancer and typically carries a good prognosis. As far as we are aware, the role for hydrogen sulfide in testicular cancer and the level of hydrogen sulfide-synthesizing enzyme have never been addressed. Here we examined cystathionine gamma-lyase (CSE) expression in several germ-cell testicular tumors.

MATERIALS AND METHODS

Tissue microarrays were employed to examine CSE expression in 32 benign testicular samples, 88 testicular seminomas, 34 embryonal carcinomas, 4 mature teratomas, and 16 yolk sac tumors, and CSE expression was compared to that seen in benign testicular tissue.

RESULTS

Compared to benign testicular tissue, CSE expression was increased in all three types of testicular neoplasm but not in mature teratomas. Highest CSE expression was identified in embryonal carcinomas, which often show a relatively aggressive clinical course.

CONCLUSION

For the first time, we show that CSE is increased in several common testicular germ-cell tumor types.

Systemic and primary cutaneous anaplastic large cell lymphoma: Clinical features, morphological spectrum, and immunohistochemical profile

Background:

T-cell lymphomas with anaplastic morphology typically comprise of anaplastic lymphoma kinase positive, anaplastic large cell lymphoma (ALK+ ALCL), ALK-negative ALCL (ALK- ALCL), and primary cutaneous ALCL (PC-ALCL). However, other entities such as diffuse large B-cell lymphoma, peripheral T-cell lymphoma, Hodgkin lymphoma, and undifferentiated carcinoma can also show similar anaplastic features.

Aims:

To study the clinical features and histological spectrum of ALCL and emphasize the role of immunohistochemistry (IHC) in their diagnosis and categorization.

Setting and Design:

Eight cases of ALCL diagnosed over a period of 4 years were selected for the study.

Materials and Methods:

Histopathological review and IHC was performed on all cases. Two ALK+ ALCL cases were tested by fluorescent in situ hybridization (FISH) for t(2;5)(p23;q35).

Results:

There were four cases of ALK+ ALCL and two each of ALK- ALCL and PC-ALCL. Histologically, all the subtypes showed pleomorphic and “hallmark” cells with strong CD30 expression and variable loss of T-cell antigens. One case of PC-ALCL was leukocyte common antigen (LCA) negative. Epithelial membrane antigen was positive in all the six systemic ALCL cases. Two cases tested for t(2;5)(p23;q35) by FISH were positive.

Conclusions:

Diagnosis of ALCL is based on recognizing the key morphological features, especially the presence of “hallmark” cells. IHC is essential for confirmation of diagnosis and excluding other malignancies with anaplastic morphology. The inclusion of CD30 in the initial IHC panel will help identify LCA negative cases and avoid misdiagnosis.

Bilateral Eagle Syndrome

Significance StatementUnilateral Eagle Syndrome is relatively rare and highlights important concepts in anatomy and pathophysiology. Bilateral Eagle Syndrome is exponentially more rare and has only been mentioned several times in the literature. Understanding the impact this can have on the human body and the severity of symptoms and sequelae is valuable for several types of specialists that treat this disorder.

Histiocytic sarcoma as a secondary malignancy: pathobiology, diagnosis, and treatment

Histiocytic sarcoma (HS) is an extremely rare non-Langerhans cell disorder with an aggressive course and limited treatment options. Recent advances in molecular/genetic sequencing have suggested a common clonal origin between various hematolymphoid disorders and cases of secondary HS. Deriving conclusions from previously reported cases of HS arising secondarily to certain hematolymphoid disorders, here we have tried to provide insight into the mechanisms influencing this evolution. We also discuss a clinical case of a 72-year-old man with a diagnosis of chronic myeloid leukemia (CML), presenting subsequently with a heterogeneous liver mass positive with a diagnosis of HS. The liver mass showed a retained BCR-ABL1 translocation suggesting clonality between the CML and HS. As seen in our case and other reported cases of HS derived secondarily, the concurrent expression of immunoglobulin heavy (IGH)-/light-chain rearrangements or cytogenetic markers common to the primary malignancy suggests an evolutionary mechanism involving lineage switching that could potentially be influenced by genetic or epigenetic cues which may occur at the level of a progenitor or the malignant cell itself.

Treatment-related MDS/AML in a patient after treatment for large-cell neuroendocrine lung cancer

Secondary leukemia is a common late complication after exposure to cancer therapies such as chemotherapy and radiotherapy. With the increase in the overall survival of cancer patients over the past 3 decades, treatment-related malignant neoplasms have increased in incidence. Secondary leukemias due to breast cancer and Hodgkin lymphoma have been studied in detail, but to our knowledge only a few case studies have reported secondary leukemias with previous lung cancer.¹⁻⁴ Lung cancer is the leading cause of cancer death in the United States.⁵ Since the overall survival (OS) as well as the progression-free survival (PFS) of lung cancer has improved, secondary malignancies, which are usually aggressive and have a poor prognosis, have become a common occurrence among survivors. The use of concurrent chemo-radiotherapy could increase the risk for secondary cancers. Here we report the case of a patient who developed treatment-related acute myelogenous leukemia (t-AML) with a likely prior myelodysplasia (t-MDS) after receiving combined chemo-radiotherapy for lung cancer.

The Shreveport Myeloma Experience: Survival, Risk Factors and Other Malignancies in the Age of Stem Cell Transplantation

BACKGROUND

The overall prognosis of multiple myeloma has improved significantly over the last 15 years. We wondered whether the overall improvement would also be seen in unselected patients in an academic center in Northwest Louisiana with a high proportion of minority patients, and if second malignant neoplasms are relevant for our patients.

MATERIALS AND METHODS

Between 1998 and 2009, 215 patients were treated for multiple myeloma at our center and had complete follow-up until May 2013.

RESULTS

The mean survival of patients with multiple myeloma increased from 3.25 to 5.34 years, which is comparable to patients treated at larger centers. No prognostic difference was observed in the subgroups of myeloma patients. Among 215 patients followed for the development of secondary cancers, 16 already had a preexisting or concomitant malignancy (7.4%) and 10 developed secondary cancers. Our data indicate a significant background of histologically unrelated cancers and a cumulative incidence of new cancers of about 20% after 10 years of follow-up. Based on SEER data, preexisting or secondary cancers were not statistically increased in our population.

CONCLUSIONS

The use of autologous transplantation and the introduction of new agents resulted in a significant improvement in the prognosis of multiple myeloma. Other cancers are not statistically increased before or after multiple myeloma is diagnosed and are not prognostically relevant.

Oligosecretory biclonal multiple myeloma

Among the plasma cell dyscrasias, non-secretory myeloma is one of the rarest. This diagnosis is based on the absence of monoclonal proteins in the serum and urine. When serum free light chains are trace and the kappa: lambda ratio normal, clonality may however be established by PCR. We present a case of an oligosecretory myeloma confirmed by PCR, which would have hitherto been classified as non-secretory.

Tracheal Non-Hodgkin's Lymphoma Masquerading as Benign Granulation Tissue: A Report of Two Cases

Primary tracheal non-Hodgkin's lymphoma (NHL) is rare, with fewer than 30 cases reported to date. We review the clinical presentation, evaluation, and treatment of 2 cases of tracheal NHL mimicking granulation tissue. The first patient was a 67-year-old man with myelodysplastic syndrome and Crohn's disease who had a recurring lesion of the proximal trachea causing significant airway obstruction. The second patient was a 47-year-old man with a history of multiple intubations who presented with dyspnea and stridor due to circumferential tracheal stenosis. In both cases, bronchoscopy revealed abundant granulation tissue, and the initial biopsy results indicated benign disease. However, after requests from the diagnostic team to rule out lymphoma, additional immunohistochemical stains and polymerase chain reaction testing confirmed NHL. Radiotherapy was initiated. The first patient responded well and remains disease-free after 4 years. The second patient died of airway obstruction due to severe distal tracheal stenosis. Recurrent granulation tissue should raise the suspicion of malignancy and prompt further tissue evaluation for evidence of lymphoma. Steroids for airway compromise may cause progression to mature stenosis as prednisone is used in the treatment of lymphoma. Localized disease involving the central airways may be treated successfully with limited chemotherapy and radiotherapy.

Karyopyknotic cytoplasmic inclusions in neutrophils

Karyopyknotic cytoplasmic inclusions in neutrophils (KPCI) have been previously called "Howell-Jolly" like inclusions and identified in immunosuppressed patients with human immunodeficiency virus (HIV) and in patients with various malignancies who have undergone chemotherapy. Attempts to characterize these inclusions have included the Grocott's methenamine silver (GMS), periodic acid Schiff (PAS), Gram, and Feulgen stains. Previous authors have concluded that these inclusions are of deoxyribonucleic acid (DNA) origin. We present a case describing an additional method to confirm this observation and to document previously undescribed curvilinear forms.

The role of fluorescence in situ hybridization and polymerase chain reaction in the diagnosis and classification of lymphoproliferative disorders on fine-needle aspiration

BACKGROUND

Fine-needle aspiration (FNA) has been used in the evaluation of lymphadenopathy for a long time and is highly reliable in the identification of metastatic malignancies. However, the role of FNA in the assessment of new lymphoproliferative disorders continues to be a subject of debate. The objective of the current study was to evaluate the role of molecular cytogenetic studies in FNA diagnoses of lymphoproliferative disorders.

METHODS

A retrospective, computer-based search for lymph node FNAs from 2006 to 2007 was performed. Cases with either fluorescence in situ hybridization (FISH) and/or polymerase chain reaction (PCR) studies were subjected to further analysis.

RESULTS

In total, 243 lymph node FNAs were performed during the period, including 104 that were positive/suspicious for metastatic malignancies, 16 that were positive/suspicious for lymphomas, 15 that demonstrated atypical lymphoid proliferation, 73 that were reactive, 14 that were deemed granulomas, and 21 that were determined to be nondiagnostic. Molecular analysis included combined FISH/PCR in 4 cases, FISH only in 7 cases, and PCR only in 4 cases. By using multiplex PCR, 6 cases with atypical/negative flow cytometry results were diagnosed as 4 B-cell lymphomas, 1 T-cell lymphoma, and 1 reactive lymph node; and 4 cases that had atypical T cells determined by flow cytometry were diagnosed as reactive. One CD10-negative follicular lymphoma and 2 cases with suspicious flow cytometry results were positive for t(14;18)(q32;q21) by FISH. Forty-five cases had follow-up histology with 3 false-negative findings and no false-positive results.

CONCLUSIONS

In this study, multiplex PCR studies for immunoglobulin heavy-chain or T-cell receptor gene rearrangements were useful for demonstrating clonality, and FISH studies were able to detect translocations or gene rearrangements that allowed for the subclassification of B-cell non-Hodgkin lymphomas.

Characterization of the lymphoid stroma in Warthin's tumor of salivary gland by immunohistochemistry, heavy chain gene and Bcl-2 gene rearrangement

Warthin's tumor is rarely associated with malignant lymphoma. Only 18 cases were reported in the literature so far. In most cases the latter is a low grade process, including Marginal zone/Mucosa associated lymphoid tissue (MALT) type lymphoma, follicular lymphoma, and rarely diffuse large cell lymphoma which may arise de novo or secondary to low grade lymphoma. This study was conducted to determine the prevalence of occult B cell monoclones and genetic alterations in Warthin's tumor. Fourteen cases of Warthin's tumor were stained with antibodies to CD3, CD20, kappa and lambda light chains. On six cases of randomly selected Warthin's tumor, polymerase chain reaction (PCR) of IgH gene rearrangement (IgH-GR) was performed on genomic DNA extracted from formalin-fixed paraffin embedded tissue. One case of primary salivary gland indolent B-cell lymphoma and 3 cases of sialadenitis were analyzed by the same methods for comparison. In all Warthin's tumor and sialadenitis cases most of lymphoid stroma was B cell phenotype and concentrated in germinal centers. T cells were mostly located between germinal centers. No light chain restriction was demonstrable by kappa and lambda immunostains. Molecular genetic studies failed to show IgH-GR by FISH and showed polyclonal by IgH PCR. In contrast, the lymphoma case showed a diffuse proliferation of small B cells with light chain restriction and a minor component of reactive T cells. FISH showed IgH-GR and bcl-2 gene translocation with monoclonality by IgH PCR. Our study concludes that the lymphoid stroma of Warthin's tumor is reactive.

Comparison of FISH and quantitative RT-PCR for the diagnosis and follow-up of BCR-ABL-positive leukemias

BACKGROUND

For Philadelphia chromosome positive (Ph+) leukemias (chronic myelogenous leukemia [CML], acute lymphoblastic leukemia [ALL], and rare other leukemias), both allogeneic transplantation and treatment with tyrosine kinase inhibitors offer chances of molecular remission (the molecular marker being consistently undetectable). Molecular remission is defined as a reduction in the quantification of BCR-ABL transcripts to an undetectable level by molecular diagnostic methods, and is considered as a surrogate marker for cure or long-term disease control. The molecular diagnostic methods including fluorescence in situ hybridization (FISH) and quantitative reverse transcription-polymerase chain reaction (QRT-PCR) are more sensitive than classical cytogenetic analysis for the detection of BCR-ABL positive cells. QRT-PCR, due to its superior sensitivity, is considered the gold standard for the follow-up of Ph+ leukemias treated with imatinib.

AIM

The objective of our study was to compare the diagnostic and clinical usefulness of FISH and QRT-PCR at different timepoints for Ph+ leukemias.

PATIENTS AND METHODS

We investigated 23 unselected patients with Ph+ CML (n = 21) or Ph+ ALL (n = 2) at 77 different timepoints in a comparative study with both FISH and QRT-PCR using commercially available reagents in a routine laboratory.

RESULTS

Our study demonstrated a good correlation of QRT-PCR with FISH in detecting the BCR-ABL fusion gene among patients with CML or ALL (coefficient of correlation = 0.77493, p < 0.0001, using Spearman's correlation procedure). All newly diagnosed or untreated cases were positive with both methods. Lower coefficients of correlation were found when FISH and QRT-PCR were correlated with the white blood cell count (WBC). An overall concordance of FISH and QRT-PCR (being either negative or positive in both tests) was found in 65 cases (84.4%) and a discrepancy identified in 12 cases (15.6%).

CONCLUSIONS

We confirm that QRT-PCR allows precise measurement of low levels of BCR-ABL transcripts and can serve as a sensitive indicator for minimal residual disease. In addition, we demonstrate in most cases a good correlation of QRT-PCR with FISH in detecting the BCR-ABL fusion gene among patients with CML or Ph+ ALL. FISH is not suitable for monitoring minimal residual disease.

Prognostic significance of pronormoblasts in erythrocyte predominant myelodysplastic patients

Recent studies of acute erythroleukemias have reaffirmed DiGuglielmo's syndrome (M6a, myeloblast-predominant) and disease (M6b, pronormoblast-predominant). M6c (mixed myeloblast/pronormoblast) has also been described. However, MDS is still defined according to the percentage of myeloblasts (% myeloblasts) without including the pronormoblast count. A 20-year retrospective study was performed to identify cases demonstrating >or=50% erythrocytic component and <30% calculated blasts (FAB exclusion criteria) without underlying cause (96 cases). Pronormoblast and myeloblast counts and other variables were analyzed as possible explanatory variables of the variations in survival. Considered alone, increasing % myeloblasts and/or percentage of pronormoblasts (% pronormoblasts) were significant predictors of decreasing survival. When all variables were considered as a multivariate group, the best fitting statistical model for predicting survival was a function of age, % pronormoblasts, IPSS cytopenias, platelet count, and percentage erythrocytic component. Of these, % pronormoblasts was by far the most significant. Nonappearance of % myeloblasts in this model is indicative of high correlations of this count with other variables.

Pathologic Studies Useful for the Diagnosis and Monitoring of Plasma Cell Dyscrasias

The pathologic diagnosis of multiple myeloma and other plasma cell dyscrasias includes histopathologic examination of a bone marrow aspirate and biopsy and clinical laboratory tests to assess end organ damage and other prognostic information. Plasma cell dyscrasias are characteristically classified and staged based on the results of these pathologic studies in conjunction with other clinical and radiologic parameters. New staging systems such as the International Staging System (ISS) use readily available laboratory tests to stratify prognostic subgroups. The continued introduction of new laboratory assays will help improve our understanding of plasma cell dyscrasias and the therapeutic management of these patients.

Increased transferrin receptor expression following 11q23 deletion as a mechanism of malignant progression in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a common adult leukemia characterized by the accumulation of mature neoplastic B-lymphocytes. Typically, CLL follows an indolent course, with most patients surviving for many years. However, 10-20% of CLL patients carry 11q23 chromosomal deletions and often exhibit a more severe disease course, with earlier onset of symptoms, shortened lymphocyte doubling time, poor response to therapy, and shortened survival. The molecular basis for 11q23 deletions resulting in a poor prognosis is currently poorly understood. The tumor suppressor gene, ataxia-telangiectasia mutated (ATM, 11q22.3-23.1), is considered a likely candidate gene whose loss could result in the poor prognosis associated with 11q23 deletion and is mutated in a significant percentage of CLL cases. Recently, recombinant ATM expression in ATM-deficient cells was found to decrease transferrin receptor (TfR) expression, suggesting that deletion of the chromosomal region carrying ATM results in increased TfR expression. TfR imports iron into cells, an event necessary for DNA synthesis and cell growth. Additionally, rapidly growing malignant cells, including lymphomas and CLL, often express high TfR levels. Based on this, we propose that one molecular mechanism by which 11q23 deletions confer a poor prognosis in CLL is via increased TfR expression secondary to ATM loss, resulting in the increased cellular iron import, and hence increased capacity for malignant growth. Our hypothesis may also partially explain why gallium, an atomically iron-like toxic metal that binds to transferrin and the TfR is incorporated into cells and was previously demonstrated to have anti-tumor activity in patients with lymphomas refractory to other chemotherapeutic treatments.

Allosensitization in Patients Receiving Multiple Blood Transfusions

Extended antigen (C, E, K) matching decreased the incidence of alloantibody (alloAB) and autoantibody (autoAB) formation, in addition to eliminating transfusion reactions in the multiply transfused sickle cell disease patients. AlloAB formation possibly transforms the immune system into a hyperactive state leading to further and earlier alloAB and autoAB formation. However, additional CEK matching results in marked overuse of Rh-negative packed red blood cell (pRBC) units, 30 minutes' extra time of a skilled technologist, and 153 dollars extra CEK reagent cost per unit to find CEK-matched pRBCs for every transfusion for these multiply transfused patients.

Fever, chills, and weakness in a 61-year-old man

A 61-year-old man presented to the emergency department of a community hospital with a 2-week history of fever, chills, and sudden extreme weakness of his right arm and lower extremities. He also had a cough, shortness of breath, nausea, abdominal pain, diarrhea, and myalgia. Though initially alert and cooperative, he quickly became unresponsive. In addition, he had hyponatremia, renal insufficiency, and compromised cardiopulmonary function. He was admitted to the intensive care unit for suspected bacterial infection and was started on broad-spectrum antibiotics. Chest radiograph revealed miliary infiltrates consistent with infectious emboli or metastatic carcinoma. Despite intensive resuscitation, the patient died 36 hours after admission. At autopsy multiple nodular lesions were observed on gross examination of the lungs, perihilar and paratracheal lymph nodes, and liver. Microscopic sections of the lung (Figure 1) and brain (Figures 2 and 3) are shown.

Pathology case of the month. 39-year-old woman with abdominal pain and weight loss. Takayasu's arteritis (TA)

A 39-year-old white woman presented with a history of aortoiliac occlusive disease diagnosed in 1992 attributed to oral contraceptive use. Shortly thereafter, aortoiliac replacement was performed. Mild hyperlipidemia was diagnosed in 2001. At the current clinic visit, she presented to her primary care physician with a 3-month history of postprandial midepigastric abdominal pain relieved by vomiting and a 30-pound weight loss. Her evaluation included an esophagogastroduodenoscopy, a colonoscopy, and an abdominal ultrasound, all of which were within normal limits. Because of her medical history, the patient underwent an arteriogram, which revealed brachiocephalic stenosis (Figure 1), occlusion of the left subclavian artery (Figures 2a and 2b), and narrowing of the superior and inferior mesenteric arteries (not shown). Since she had discontinued her oral contraceptives in 1992 and her hyperlipidemia was mild, the rheumatology service was consulted to evaluate this patient. On physical examination, she had decreased left brachial and radial pulses and a right carotid bruit. Laboratory evaluation revealed a normal complete blood count, comprehensive metabolic panel, erythrocyte sedimentation rate, and C - reactive protein. Subsequent testing included a prothrombin time, activated partial thromboplastin time, protein S, protein C, reptilase time, antithrombin III, anticardiolipin antibody, antiphospholipid antibody, lupus anticoagulant, homocysteine, RPR, and a lipid profile. All test results were within normal limits. Due to the severity of her abdominal pain, the patient underwent superior mesenteric artery (SMA) bypass surgery. Sections from the aorta resected in 1992 are shown in Figures 3 and 4.

Fluorescence in situ hybridization: method of choice for a definitive diagnosis of mantle cell lymphoma

Fluorescence in situ hybridization (FISH) using IGH/CCND1 probes was used to analyze 35 specimens including 27 paraffin sections, 3 bone marrow aspirates, and 5 peripheral blood smears. The 27 paraffin sections included 7 bone marrows, 10 lymph nodes, 3 spleens, 3 tonsils, 3 gastrointestinal biopsies, and 1 skin biopsy. Among these cases, 23 specimens were from 20 patients with mantle cell lymphoma (MCL) and 12 specimens were from 12 patients with non-MCL lymphomas/lymphoid hyperplasia. Specimens from all MCL patients showed positive results with FISH. In one patient, the archived paraffin sections were negative with FISH, but a fresh peripheral blood specimen showed a positive result. Negative results were obtained in all specimens from non-MCL cases. Flow cytometric analysis revealed that all cases of MCL showed CD19/CD5 staining, but the percentages of cells positive for CD23 and FMC-7 were variable, thus they cannot be depended upon for a definitive diagnosis of MCL. Immunohistochemical stains demonstrated positive staining for CD5 and CD20 and negative staining for CD23 in MCL cases but cyclin D1 was positive in only 10 of 13 MCL cases studied. Therefore, it appears that immunophenotyping alone is not sufficient to establish a definitive diagnosis of MCL. FISH should be routinely used when the diagnosis needs confirmation. FISH can be performed in a routine clinical laboratory, and it is applicable to archived material for retrospective studies. Other molecular cytogenetic techniques in comparison with FISH are discussed.

Laboratory diagnosis of von Willebrand disorder. Current practice in the southern hemisphere

A survey of 44 laboratories was conducted to evaluate current testing proficiency in the diagnosis of von Willebrand disorder (vWD) and to assess recent changes in test practices. Laboratories performed their usual panel of tests for vWD and interpreted results for the likelihood of vWD and potential subtype. Samples were as follows: normal plasma; borderline normal or abnormal levels of von Willebrand factor (vWF) and factor VIII; type 3 vWD; type 2A vWD; and 2 samples from a healthy person, processed after handling at 22 degrees C and 4 degrees C, respectively. Interassay and within-method coefficients of variation were similar for all assays (approximately 15%-25%). Most laboratories reported test values consistent with expected findings and made correct interpretations, although discrepant results for 5% to 10% of responses are of concern. For the sample stored at 4 degrees C, all laboratories detected low or borderline levels of vWF and factor VIII coagulant, and no laboratory identified this sample as from a healthy person. In contrast, for the sample stored at 22 degrees C, most laboratories reported normal results. Compared with previous results, performance of some assays has declined while that of others has increased. Laboratories generally are proficient in tests for vWD, and transport of samples at 4 degrees C before processing may lead to false identification of vWD, suggesting that NCCLS guidelines should be reviewed.

Bone marrow biopsy: interpretive guidelines for the surgical pathologist

Ideally, the bone marrow core biopsy should be reviewed with knowledge of the clinical history, complete blood count, and findings in the peripheral blood and bone marrow aspirate smears. However, for a variety of reasons, the pathologist may receive the core biopsy and aspirate clot section without all of this information. Although this approach is not optimal, a great deal of valuable information can be generated from these specimens. Over the past 20 years, there has been considerable progress in the fields of flow cytometric analysis, immunohistochemistry, and molecular diagnostic studies that can be performed on smears or extracted DNA from paraffin embedded tissue. These modalities have augmented and refined diagnostic criteria formerly ascertained by light microscopy, cytochemistry, and cytogenetics. This is particularly true of some myeloid and lymphoreticular neoplasms where a collaborative and multidisciplinary approach to the diagnosis has become necessary. Despite this growing complexity and dependence on newer methodologies, the traditional role of histopathology in evaluating the bone marrow biopsy remains as important as it has been in the past. In this review, we focus on contemporary practices and expectations for interpreting bone marrow biopsies and clot sections.