Initial Bone Marrow Biopsy Research Articles

Isolated Chromosome 20q Deletions in Patients with Non-Myeloid Disorders

AbstractAbstract 1442 Background:Deletions of the long arm of chromosome 20 have conventionally been associated with myeloid neoplasms. The frequency of chromosome 20q deletion (del(20q)) is 1–10% in myeloid diseases and associated with good prognosis in patients with myelodysplastic syndromes (MDS) and poor response to treatment in patients with acute myeloid leukemia (Greenberg 1997; Campel 1994). Previously chromosome 20q deletions were thought to be pathognomonic for myelodysplastic syndrome. Due to the observation that del(20q) may be present in non-malignant clones in patients with non-myeloid cancers, the 2008 WHO Classification (Swerdlow ed.) stated that MDS could not be diagnosed solely on the basis of isolated del(20q). The significance of isolated del(20q) in non-myeloid disorders have yet to be defined. When this chromosomal abnormality is found incidentally in marrows of patients for non-myeloid cancers, some oncologist may consider altering plans for cytotoxic chemotherapy out of concern for developing MDS. The aim of this study was to determine if isolated del(20q) in non-myeloid disorders implies an impending myeloid disease and if treatment should be altered for such patients. Methods:We conducted a retrospective, single institution cohort study among patients who between January 2005 and July 2012 were found to have 20q deletions without other chromosomal alterations per conventional cytogenetics and non-myeloid disorders per clinical history or bone marrow biopsies. Patients with isolated 20q deletion were identified from the clinical cytogenetic laboratory database and results were reviewed per cytogeneticist for accuracy. Pathology reviewed initial and subsequent bone marrow biopsies for histopathologic or immunophenotypic evidence of a myeloid disease. If a subsequent bone marrow exam was not available, the patient’s complete blood counts were reviewed to determine if they developed clinical evidence of a myeloid disorder. We defined clinical suspicion for MDS as the development of transfusion dependence (≥1 unit red blood cell transfusion every 8 weeks over 4 months), any grade = 2 anemia with either grade = 2 thrombocytopenia or grade = 2 neutropenia not related to chemotherapy or immunotherapy, or any grade = 3 cytopenia without known etiology. For patients undergoing chemotherapy, MDS was suspected if there was evidence of poor bone marrow reserve as manifest by dose modifications or delays for hematologic toxicity. Results:Thirty nine patients with isolated del(20q) were identified in the cytogenetic database from January 2005 to July 2012. Twelve out of thirty nine (31%) patients were found to have non-myeloid disorders. Three patients with multiple myeloma (25%), two patients with chronic lymphocytic leukemia (17%), two patients with autoimmune disorders (17%) and five others with breast cancer, diffuse large B cell lymphoma, monoclonal gammopathy of undetermined significance, Crohn’s disease and melanoma. There were an equal number of men and woman with median age of 60 years (range 30–83 years) at the time of isolated del(20q) detection. Six patients were found to have del(20q) at the initial presentation of their disease and six developed del(20q) after undergoing treatment. Nine patients were treated with standard first line systemic therapies. Six of the nine patients were treated with chemotherapy and four of them did not have to undergo any dose modifications due to myelosuppression. In the patients with chronic lymphocytic leukemia, FCR (Fludarabine,Cyclophosphamide and Rituximab) was dose modified and later discontinued due to persistent neutropenia and thrombocytopenia. After a median follow up of twenty two months (range 2 – 64 months) no patients developed evidence of a myeloid disorder by bone marrow pathology or clinical evidence. Conclusion:Isolated deletion of the long arm of chromosome 20 in patients with non-myeloid disorders does not result in bone marrow failure or myeloid disease, therefore physicians should not alter their treatment plans. Further patient follow up is necessary to provide more insight on the prognosis and treatment of non-myeloid disorders with isolated chromosome 20q deletion. Disclosures:No relevant conflicts of interest to declare.

Pure Erythroid Leukemia Mimicking Megaloblastic Anemia in a Bone Marrow: A Potential Diagnostic Pitfall

The differential diagnosis between acute erythroid leukemia and megaloblastic anemia can be very challenging. Herein we report a case of pure erythroid leukemia that was diagnosed as megaloblastic anemia on the initial bone marrow biopsy. The patient was a previously healthy 60-year-old man who had pancytopenia. His serum vitamin B12 was slightly low. A bone …

Autopsy case of primary myelofibrosis in which myeloid sarcoma was the initial manifestation of tumor progression

Myeloid sarcoma (MyS) is defined as an extramedullary tumor-forming neoplasm consisting of immature myeloid cells with/without maturation. We experienced a case involving a 68-year-old Japanese male patient who had been followed-up for four years with a diagnosis of chronic idiopathic myelofibrosis/primary myelofibrosis (PMF) and noticed a painful mass in his left axilla. A wedge biopsy characterized the lesion as MyS that displayed megakaryoblastic/megakaryocytic differentiation. As his complete blood count included a few myeloid blasts (1% of WBC) and a bone marrow biopsy detected fibrosis without evidence of acute myelogenous leukemia (AML), a diagnosis of extramedullary blastic transformation of PMF was made, which was confirmed later by V617F mutation in Janus kinase-2 in both initial bone marrow biopsy and axillary tumor biopsy specimens. The patient died of pneumonia eight months after developing the axillary tumor. At autopsy, multiple MyS masses were detected in his soft tissue, but his bone marrow only contained fibrosis. Although MyS rarely develops before the leukemic transformation of PMF, no evidence of AML could be found in the patient's bone marrow at any point during the course of his disease. Thus, it is possible that the blasts in his peripheral blood were derived from the remaining MyS. Furthermore, the present case indicates that extramedullary blastic transformation, which is occasionally seen in CML, can also occur in PMF. Therefore, it is important to recognize that there is a wide variation in the pathogeneses of MyS and PMF.

An Uncommon Presentation of Adult Hemophagocytic Lymphohistiocytosis with Severe Pulmonary Hypertension

Abstract 4734 Introduction:Adult hemophagocytic lymphohistiocytosis (HLH) is a rare and potentially life-threatening hyperinflammatory syndrome that presents both diagnostic and therapeutic challenges. HLH may be primary and related to an underlying genetic abnormality or secondary to infection, malignancy, or rheumatologic condition. We describe a case of HLH in a latently EBV-/CMV-/HBV-immune 52-year old male co-presenting with severe pulmonary hypertension and a novel heterozygous perforin missense exon mutation. He was intolerant of the HLH 2004 protocol but responded to salvage alemtuzumab therapy, which was then followed seven weeks later by a fatal polymicrobial sepsis. Case Presentation:This previously healthy 52 year-old male developed the insidious onset of acral paresthesia and exertional dsypnea over a two year period. Seven months prior to admission, he was treated as an outpatient for suspected H1N1 infection, followed by the development of spontaneously-resolving superior oblique nerve palsy, with the EMG/NCS correlate of demyelinating polyneuropathy and secondary axonal loss. His dyspnea progressed, and he presented to hospital with fevers, weight loss, and respiratory distress requiring mechanical ventilation. His course in the intensive care unit was complicated by nephrotic range azotemia (Cr >200 umol/L), cryptogenic hepatitis (transaminases >1000 IU/ml), and splenomegaly. Hematologic investigations initially revealed an isolated thrombocytopenia that was IVIg and steroid refractory, followed by hemolytic anemia with oxidative blood film abnormalities, and an initial bone marrow biopsy devoid of hemophagocytosis. Rheumatologic serologies (ANA, ENA, C3, C4, p-ANCA, c-ANCA, ds-DNA, anti-GBM) and microbiologic studies (HIV, Monospot, and indices of reactivation of HBV or CMV) were negative. Other causes of peripherally destructive cytopenias were also ruled out (DAT, PNH flow cytometry, APLA, ADAMTS13, methemoglobin, G6PD, PK normal).Four weeks after admission, worsening pancytopenia and unexplained fevers prompted a second bone marrow examination, which demonstrated hemophagocytosis with an EBV reactivation viral load of 7 × 105/ml. Meeting clinicopathologic diagnostic criteria for HLH, the HLH 2004 protocol was thus initiated. Within 7 days, treatment-limiting nephrotoxicity and hepatotoxicity developed, prompting discontinuation of cyclosporine and dose-reduction of etoposide. Hepatic biopsy revealed drug-induced sinusoidal necrosis without lymphohistiocytic infiltration. Worsening HLH prompted the next-line use of anti-CD52 monoclonal therapy (alemtuzumab), which associated with the onset of freedom from transfusion within 35 days. Over the six week course of therapy, clinical, biochemical, and hematologic manifestations continued to improve. In parallel with sildenafil, the pulmonary hypertension was also dramatically alleviated. He thus remained in a transfusion-free remission for 55 days until day 105 after diagnosis.Fevers then recurred, with polymicrobial sepsis complicated by disseminated intravascular coagulation, respiratory failure, and hematopathologic evidence of macrophage re-activation. The goals of care were changed to comfort measures and the patient succumbed. Autopsy revealed disseminated blastomycosis with relapsed HLH. Perforin gene sequencing identified a novel heterozygous exon missense single nucleotide polymorphism 1517A>C (His506Pro). Conclusion:This is an extraordinary case of adult EBV-reactivation-associated HLH presenting with severe pulmonary hypertension, a novel perforin gene mutation, intolerance towards the HLH-2004 protocol, and responsiveness to alemtuzumab. Fatal secondary infections, including the discovery of disseminated blastomycosis, presaged or provoked the concomitant relapse of HLH. The relevance of the unique perforin mutation or the co-infection with Blastomyces with respect to the atypical features of this HLH presentation remains unknown. Disclosures:Off Label Use: Alemtuzumab (anti-CD52) was used off-label in the salvage management of hemophagocytic lymphohistiocytosis (HLH).

Intérêt de la biopsie ostéomédullaire dans la thrombocytémie essentielle

The recent discovery of the Janus Kinase 2 (JAK2(V617F)) mutation, an indicator of clonal expansion, has widely modified the diagnostic work-up of myeloproliferative disorders. However, histopathologic criteria of the WHO classification, focused on megakaryocytes abnormalities, have taken a central role in the diagnosis of essential thrombocytemia (ET), particularly to distinguish it from the prefibrotic myelofibrosis (PMF) evolving to a clinic myelofibrosis unlike true ET. The aim of our study is to evaluate inter-observer reproducibility and prognostic implications of these pathological criteria comparing diagnoses with clinical and biological follow-up. Forty-four patients presenting with isolated thrombocytemia were retrospectively evaluated. All patients were initially diagnosed with ET based on the PVSG classification from 1997. The initial bone marrow biopsy specimens were re-evaluated using the Thiele pathological classification: true ET, prefibrotic myelofibrosis (PMF) and early myelofibrosis. Patients were followed for a median of 6 years. Our population includes three patients with polycythemia vera and 41 patients with true ET. Based on clinical and biological follow-up, diagnoses were changed to idiopathic myelofibrosis in four of six patients with "early" myelofibrosis (66.7%), but in only one of 14 patients with PMF (7.15%). In contrast, the diagnosis of true ET was not changed in the 21 cases. Inter-observer reproducibility for pathological classification was 100%. In this study, our diagnostic methodology based on the clinico-biological follow-up, which has not been evaluated in previous studies, calls into question the diagnostic value of the pathological criteria in PMF.

Assessment of fibrosis and vascularization of bone marrow stroma of chronic myeloid Leukemia patients treated with imatinib mesylate and their relationship with the cytogenetic response

Chronic Myeloid Leukemia (CML) is a myeloproliferative disease characterized by the presence of the Philadelphia chromosome (translocation between chromosomes 9 and 22), resulting in the formation of the hybrid BCR-ABL protein. Currently, the treatment of CML patients is performed with imatinib mesylate (IM), which promotes the elimination of leukemic cells by inhibiting the kinase activity of BCR-ABL. This study evaluated the effectiveness of IM by monitoring 22 CML patients in a chronic phase treated at the CEPON/SC with IM for a minimum follow-up period of two years. Cytogenetic Response (CR) and bone marrow biopsies (BMB) were evaluated before and after IM treatment. BMB were evaluated by detection of reticulin degree and vascularization. The results were correlated to the CR. Mean time to achieve CR was 9 months and was attained by 77.27% of the patients. The results from the initial BMB analysis showed that 59.09% presented reticulin of between 2+ and 4+ whereas after treatment, only 27.17% presented this degree. With regard to vascularization of the initial sample, 90.91% were graded between II and IV, whereas after treatment, 40.91% had this degree. The results suggest a positive correlation of degree of reticulin and vascularization with CR.

An Interesting Case of Hemophagocytic Lymphohistiocytosis Presenting with Pulmonary Hypertension

AbstractAbstract 4728 Introduction:Adult hemophagocytic lymphohistiocytosis (HLH) is a rare and potentially life-threatening hyperinflammatory syndrome that presents both diagnostic and therapeutic challenges. HLH may be primary and related to an underlying genetic abnormality or secondary to infection, malignancy, or rheumatologic condition. We describe a case of HLH in a latently EBV-/CMV-/HBV-immune 52-year old male presenting with severe pulmonary hypertension. He was intolerant of the HLH 2004 protocol but responded to salvage therapy with anti-CD52 monoclonal therapy (alemtuzumab). Case Presentation:The patient was previously healthy with a diagnosis of axonal-pattern CIDP five years prior. He had a one year history of mild progressive exertional dyspnea and experienced a flu-like illness treated as presumed H1N1 infection five months prior. He presented to hospital with progressive respiratory distress, fevers and weight loss, culminating in respiratory failure requiring mechanical ventilation for 4 days. Investigations revealed severe pulmonary hypertension (RVSP 112 mmHg), nephrotic range proteinuria, transaminitis, hyperferritenemia (ferritin 4240 ug/L) and hepatosplenomegaly. Initial hematologic investigations revealed an isolated thrombocytopenia (IVIG and steroid non-responsive), soon followed by hemolytic anemia with an oxidative blood film. Initial bone marrow biopsy showed normal hematopoiesis, megakaryoyctic thrombocytopenia, iron deficiency, and no evidence of hemophagocytosis. Rheumatologic investigations were negative (ANA, ENA, C3, C4, p-ANCA, c-ANCA, ds-DNA, anti-GBM) and viremia investigations negative (HIV, CMV, EBV, HBV). Hematologic causes of peripherally destructive cytopenias were ruled out (DAT, PNH, methemoglobin, APLA, ADAMTS13, G6PD, PK normal). No definitive etiology of pulmonary hypertension was found and treatment was initiated with nitric oxide and sildenafil. Four weeks after initial presentation to hospital, he developed worsening pancytopenia and unexplained fevers. Repeat bone marrow examination revealed hemophagocytosis, achieving sufficient criteria for diagnosis with HLH. Repeat EBV serology was IgM positive with a viral load 7 × 105/ml. HLH 2004 protocol was initiated, however within 7 days, treatment-limiting nephrotoxicity and hepatotoxicity developed, prompting discontinuation of cyclosporine and dose-reduction of etoposide. Hepatic biopsy revealed drug-induced sinusoidal necrosis with no HLH involvement. Evidence of worsening HLH (ongoing fevers, cachexia, debility, severe cytopenias requiring transfusion and filgrastim support, and increasing ferritin) prompted the use of alemtuzumab. Within 7 days of alemtuzumab initiation the ANC increased from less than 0.2 to within normal range, and within 14 days platelet count rebounded to above 50. Ferritin fell from a peak of 4756 ug/L to approximately 1500 ug/L. Treatment course was complicated by severe upper and lower gastrointestinal bleeds (necessitating massive transfusion protocol), pulmonary blastomycosis (treated with ambisome and itraconazole) and several episodes of bacteremia. Despite his precarious course in hospital, he responded to 6 weeks of treatment with alemtuzumab with continued improvement in his clinical, biochemical, and hematological manifestations of HLH. At 105 days of post-diagnosis follow-up to date, his HLH remains in remission with gradual, ongoing improvement in pulmonary hypertension. Although no clear diagnostic association has been proven, we hypothesized that either this patient's pulmonary hypertension and HLH had a common precipitant or that his pulmonary hypertension was secondary to HLH disease activity. Conclusion:This is a unique case of HLH presenting concurrently with severe pulmonary hypertension, complicated by intolerance of the HLH 2004 protocol, but response to salvage anti-CD52 therapy. There is still much to be understood about the underlying pathophysiology and treatment strategies of HLH. Disclosures:Off Label Use: Alemtuzumab is a monoclonal antibody which targets CD52. It is used as second-line treatment for chronic lymphocytic leukemia. It is also used off-label for other lymphocyte/NK cell disorders, such as cutaneous T-cell lymphoma and some autoimmune diseases. It has been described in off-label use for hemophagocytic lymphohistiocytosis (HLH) as a bridge to allogeneic stem cell transplant.

Cephalosporin-induced recurrent aplastic anemia

Cephalosporin-induced recurrent aplastic anemia

Dose-modified lenalidomide induces sustained hematological response in patients with intermediate to high risk myelodysplasia

No Abstract Available

Pediatric-onset mastocytosis: a long term clinical follow-up and correlation with bone marrow histopathology.

Pediatric onset mastocytosis usually presents as urticaria pigmentosa; and less often as diffuse cutaneous mastocytosis. While the literature indicates that disease often resolves, there has been a move to more aggressive therapy for mastocytosis early in life. We addressed the long term prognosis of pediatric-onset disease by examining 17 children with mastocytosis which we had reported on in 1989 [1]. We successfully contacted 15 of these patients and data was collected regarding their clinical status. Original bone marrow specimens were re-stained, re-examined, and correlated with disease outcome using consensus criteria. Three of five patients with persistent disease underwent repeat bone marrow biopsies. There was complete regression of disease as defined by cutaneous findings and symptoms (clinical disease severity) in 10 of 15 patients (67%). Three patients had major (20%) and two had partial regression of disease (13%). Repeat marrow examinations on three patients with persistent disease documented systemic mastocytosis based on marrow findings in one patient who had partial regression of disease and was the only patient with initial morphologic evidence of systemic disease. Of the remaining two patients, one demonstrated partial regression and the other major regression of disease; and neither had evidence of systemic mastocytosis. This study demonstrates that initial bone marrow biopsies were prognostic in that those without evidence of systemic disease experienced disease regression; and that the long term prognosis for children managed symptomatically with mastocytosis is highly encouraging.

Basophilic leukemia in recurrent chronic myelogenous leukemia blast phase

A 31-year-old man with a four-year history of chronic myelogenous leukemia (CML) presents in his second blast phase. The patient’s initial diagnosis was made after routine analysis revealed a white blood cell count (WBC) of 353 10/L. Initial bone marrow biopsy results and cytogenetics were not available for review. The patient responded initially to hydroxyurea followed by imatinib mesylate, at 400 mg daily. A subsequent bone marrow was consistent with morphologic remission; results of cytogenetics and molecular studies were not available. After *3-years, a repeat bone marrow biopsy revealed myeloid blasts comprising 80% of cells consistent with blast phase of CML. Retrospective review of peripheral blood and bone marrow showed only rare (less than 1%) blasts containing granules resembling immature basophils. RT-PCR was positive for BCR-ABL transcript (p210 and p190), and chromosome analysis showed 47, XY, t(2;3)(p23;q29), +8, t(9,22)(q34; q11.2) in 20 of 20 metaphase spreads. Flow cytometric analysis revealed a CD45 positive blast population with moderate side light scatter that strongly expressed CD34, CD117, and CD7 as well as variably expressed CD13, CD33, CD11c, and CD2. Intracellular staining revealed that 1/3 of these cells were myeloperoxidase positive. The imatinib mesylate dose was increased to 800 mg daily but was not tolerated due to nausea. The imatinib mesylate was discontinued, and a second generation ABL kinase inhibitor was initiated. The patient responded to this drug for several months until severe abdominal pain lead to its discontinuation. Less than one week after discontinuation the patient was found to have a WBC of 17 10/L with 30% blasts in peripheral blood, and the tyrosine kinase inhibitor was restarted. Circulating blasts persisted, and the patient underwent induction chemotherapy with an eventual goal of allogeneic transplant. Following this treatment, blasts were no longer detected in peripheral blood, and the patient was thought to be in hematologic remission. After *3-months our patient presented with a WBC of 47 10/L and 76% blasts. These results are consistent with recurrent CML blast phase, though morphologic remission was not established by bone marrow biopsy and persistence of earlier blast crisis remains a possibility. Multiple blast populations were detected morphologically in peripheral blood (Images 1–3), and presence of metachromatic granules after toluidine blue stain indicated a subset (9% of blasts) of basophilic origin (Image 4); maturing basophils were also present (4% of WBC). The patient has since entered a research protocol and had response to a different second generation ABL kinase inhibitor. After 3-weeks of therapy, his WBC has decreased to 1.9 10/L, although occasional blasts (6%) persist. CML is a myeloproliferative disease of bone marrow derived stem cells that contain fusion of BCR on chromosome 22 with c-ABL on chromosome 9 (i.e. Philadelphia chromosome) and which characteristically produces the p210 fusion protein. The initial indolent chronic phase of CML is unstable, and the disease ultimately progresses to accelerated and blast phases. Since the Philadelphia chromosome can be detected in all hematopoietic lineages the blast phase may include neutrophilic, eosinophilic, monocytic, erythroid, megakaryocytic, and basophilic blasts in predominance or in any combination. In about 20–30% of patients the blast phase is due to proliferation of lymphoblasts, and rare patients may have both myeloid and lymphoid blast populations. Acute basophilic leukemia represents <1% of all cases of acute myelogenous leukemia (AML) and must be differentiated from the blast phase of CML, AML with maturation associated with 12p abnormalities or t(6;9), acute eosinophilic leukemia, and acute lymphoblastic leukemia with prominent coarse granules. The persistence of t(9,22), as in the described case, is strong evidence for a predominant basophilic blast population arising from abnormal CML stem cells.

Can [18F]fluorodeoxyglucose positron emission tomography imaging complement biopsy results from the iliac crest for the detection of bone marrow involvement in patients with malignant lymphoma?

To assess the usefulness of [18F]fluorodeoxyglucose positron emission tomography in the detection of bone marrow involvement in malignant lymphoma, and its impact in clinical management. One hundred and six consecutive patients with a confirmed diagnosis of lymphoma, referred for staging or restaging of Hodgkin's lymphoma (n=18) or non-Hodgkin's lymphoma (n=88), were reviewed retrospectively. A positron emission tomography scan and bone marrow biopsy of the iliac crest were performed in all patients. The assessment of bone marrow involvement by lymphoma was confirmed by histology and/or progression of bone marrow lesions in clinical follow-up. In 28 of 106 patients, bone marrow involvement was found. Positron emission tomography was more sensitive (86%) than bone marrow biopsy (57%). Positron emission tomography and bone marrow biopsy were concordant by positive correlation in 12 of 28 cases (43%) and by negative correlation in 77 of 78 cases (99%). Ten cases of non-Hodgkin's lymphoma and two cases of Hodgkin's lymphoma with positive positron emission tomography results and an initial negative bone marrow biopsy showed clinical progression of the bone marrow lesions and/or subsequent positive histology. These were considered as false-negative results for bone marrow biopsy. In seven of the 12 positive cases with negative bone marrow biopsy, positron emission tomography uptake distant from the site of the biopsy was seen. In four cases of follicular lymphoma, the bone marrow biopsy was positive and the positron emission tomography scan was normal. Positron emission tomography and bone marrow biopsy are complementary in assessing the presence of bone marrow involvement in patients with malignant lymphoma. In our series, positron emission tomography was more sensitive than bone marrow biopsy in Hodgkin's and non-Hodgkin's lymphoma, except in follicular lymphoma.

Immunohistochemical detection of CD 95 (Fas) & Fas ligand (Fas-L) in plasma cells of multiple myeloma and its correlation with survival

Multiple myeloma (MM) is a malignant disease resulting from an uncontrolled proliferation of a neoplastic plasma cell clone in the bone marrow, which might also be induced by the loss of control on apoptosis. Fas ligand (Fas-L), a member of the tumor necrosis factor family, induces apoptosis mediated via its transmembrane death receptor Fas (Apo-1/CD95) antigen. In the present study, immunostaining was performed on the initial diagnostic bone marrow biopsies of 36 MM patients (1 stage I, 5 stage II, 30 stage III), to evaluate the distribution of Fas receptor and Fas-L on malignant plasma cells. Both Fas and Fas-L were positive in 13 cases and negative in 3, whereas 10 cases were Fas-negative, Fas-L-positive and 10 were Fas-positive, Fas-L-negative. Although no association was found between the expression of Fas receptor or Fas-L and overall survival, Fas-L positivity was significantly associated with a shorter event-free survival (p = 0.0335). In this study, it has been shown that the expression of Fas-L, in malignant plasma cells of myeloma patients significantly shortens the event-free survival, indicating that the defect in apoptosis might be associated with disease progression in MM.

Megakaryocyte Features and bcr/abl Translocation in Chronic Myeloid Leukemia following Imatinib Mesylate (STI571) Therapy—a Fluorescence in-situ Hybridization Study

Following therapy with imatinib (STI571) hematologic and cytogenetic response in chronic myeloid leukemia (CML) is associated with conspicuous alterations of bone marrow (BM) morphology. Besides reduction of cellularity and fibrosis, small megakaryocytes characteristic for this disorder were replaced by large, normally appearing cells of this lineage. However, it is not known whether and to which extent these changes are accompanied by a loss of the bcr/abl translocation. Therefore an immunohistochemical (CD61) and fluorescence in-situ hybridization (FISH) study was performed on sequential BM biopsies in 5 patients with CML receiving STI571 without any pretreatment. Morphometric analysis revealed that the prevalent population of 47% micromegakaryocytes (size < or = 150 microm2) was significantly reduced (15%) during therapy and that a conspicuous shift to medium-sized and large megakaryocytes occurred. According to FISH analysis in the initial BM biopsy sections 71% of all myeloid cells exhibited the bcr/abl gene and concerning megakaryopoiesis about 65% of the prominent micromegakaryocytes displayed positive signals. After treatment this peculiar cell population decreased significantly while the emerging large megakaryocytes (52%) totally lacked a bcr/abl labeling. Because cytogenetic response and reduction of micromegakaryocytes seem to be linked, this feature may be useful to monitor therapeutic efficacy by evaluating BM morphology.

Reversal of bone marrow angiogenesis in chronic myeloid leukemia following imatinib mesylate (STI571) therapy

AbstractThe effect of imatinib mesylate (imatinib) therapy on angiogenesis and myelofibrosis was investigated and compared with interferon (IFN) and hydroxyurea (HU) in 98 patients with newly diagnosed Philadelphia chromosome-positive/BCR-ABL+ (Ph+/BCR-ABL+) chronic myeloid leukemia in first chronic phase and no other pretreatment. By means of immunostaining (CD34) and morphometry, a relationship between microvessel frequency and fiber density was detectable in initial bone marrow (BM) biopsies and sequential examinations after at least 8 months of therapy. First-line monotherapy with imatinib induced a significant reduction (normalization in comparison with controls) of microvessels and reticulin fibers. In most patients, decrease in BM vascularity was associated with a complete cytogenetic response. A significant anti-angiogenic effect was also observed after HU treatment, contrasting with IFN administration or combination regimens (IFN plus HU). In conclusion, our data support the anti-angiogenic capacity of imatinib by normalization of vascularity. In contrast, hematologic response following IFN treatment is independent from BM angiogenesis. (Blood. 2004;103:3549-3551)

Hepatosplenic gamma/delta T-cell lymphoma in bone marrow. A sinusoidal neoplasm with blastic cytologic features.

We report 8 cases of hepatosplenic T-cell lymphoma (HSTCL) involving bone marrow and correlate histologic findings with disease progression. Immunophenotypic analysis demonstrated mature, aberrant gamma/delta T-cell immunophenotypes. Isochromosome 7q was identified in 4 cases; 1 case showed the t(7;14)(q34;q13). Seven of 7 cases tested had monoclonal TCR gamma gene rearrangements. The initial diagnostic bone marrow biopsy specimens were hypercellular with a frequently subtle, predominantly sinusoidal infiltrate of atypical small to medium-sized lymphoid cells. In all cases, aspirate smears at diagnosis and in subsequent specimens contained malignant cells that resembled blasts, some with fine cytoplasmic granules. With progression, the pattern of HSTCL in bone marrow biopsy specimens became increasingly interstitial, and the neoplastic cells became larger. In aspirate smears, the proportion of blasts increased. Seven patients died; 1 was lost to follow-up. Autopsy performed on 1 patient demonstrated malignant cells within vascular channels in all organs sampled, with relatively little tumor formation, resembling intravascular lymphoma at these sites. HSTCL often can be recognized in bone marrow by its unique combination of a sinusoidal pattern in core biopsy specimens and blastic cytology in aspirate smears.

Bone marrow involvement in lymphomas with hemophagocytic syndrome at presentation: a clinicopathologic study of 11 patients in a Western institution.

Hemophagocytic syndrome (HPS) is a clinicopathologic syndrome that can reveal a non-Hodgkin's lymphoma. The pathologic features of lymphoma associated with HPS remain ill defined. We studied 11 lymphomas associated with HPS on initial bone marrow biopsies, consecutively diagnosed during a 6-year period in a Western institution. There were seven diffuse large B-cell lymphomas (DLBCLs), three T-cell lymphomas (one peripheral T-cell lymphoma unspecified, two hepatosplenic gammadelta T-cell lymphomas [HS gammadeltaTLs]), and one aggressive NK-cell lymphoma/leukemia (NKL). These lymphomas shared common clinicopathologic features with a systemic presentation, a poor outcome (nine patients died within 2 years), and a mild interstitial lymphoid infiltrate of the bone marrow at presentation in nine patients. This equivocal lymphoma infiltrate was blending with normal hematopoietic cells, and CD20 and CD3 immunolabelings were essential for its detection. A high number of reactive T (CD3+) cells, most often with a predominant cytotoxic (CD8+ TiA1+) phenotype, was present in all DLBCLs. By in situ hybridization, Epstein-Barr virus was detected in neoplastic cells of three cases (one DLBCL, one HS gammadeltaTL, and one NKL), which also showed serum viral DNA. Polymerase chain reaction studies disclosed HHV6 DNA sequences in tumor tissues of two DLBCLs, whereas HHV8 DNA was not detected. Because tumor mass indicative of lymphoma was not striking in most patients, bone marrow biopsy appears to be of great value for the diagnosis of an HPS-associated lymphoma, which may be, in Western patients, of B- as well as T- or NK-cell type. Immunostaining for CD3 and CD20 is essential to identify the common subtle lymphoma involvement. Together with a better understanding of the pathogenic processes, an early diagnosis may improve the prognosis of HPS-associated lymphoma.

HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS ASSOCIATED WITH VISCERAL LEISHMANIASIS

A 2-year-old child presented with fever and hepatosplenomegaly. Laboratory findings showed pancytopenia, hypertriglyceridemia, hyperferritinemia, and high levels of soluble-IL2 receptors. Initial bone marrow aspiration and biopsy revealed mild hemophagocytosis. A diagnosis of hemophagocytic lymphohistiocytosis was made and appropriate treatment was begun. Repeated marrow aspiration performed because of lack of clinical response revealed Leishmania amastigotes in macrophages in addition to active hemophagocytosis. Treatment with liposomal amphotericin resulted with rapid recovery. Visceral leishmaniasis should be considered in the differential diagnosis of hemophagocytic syndrome.

Bcl-2 expression by myeloid precursors in myelodysplastic syndromes: relation to disease progression

Rationale and methods: the bcl-2 oncogene blocks apoptosis in various cell types and is expressed by normal myeloid precursors, declining with maturation. To investigate whether bcl-2 plays a role in the increase of myeloblasts in myelodysplastic syndromes (MDS) and their progression to acute myeloid leukemia (AML), we studied bcl-2 expression in initial (pre-therapy) bone marrow biopsies from MDS at early (refractory anemia, RA, with or without ring sideroblasts) and advanced stages (RA with excess blasts, and in transformation). Sequential biopsies were also studied to evaluate the effect of time or disease progression, including evolution to AML, or therapy with granulocyte colony stimulating factor (G-CSF). Early myeloid precursors (EMPs), predominantly myeloblasts, were identified in paraffin sections after immunostaining; bcl-2-positive EMPs were enumerated as a percentage of all EMPs (Bcl-2%), and by their absolute frequency per ×900 microscopic field (Bcl-2 index). Findings: in initial biopsies, the Bcl-2% and Bcl-2 index in early MDS (9.9±2.6 and 1.4±0.6, respectively; mean±S.E.) were significantly lower than in advanced MDS (26.4±3.6, 4.6±1.4), but similar to controls (8.1±0.3 and 0.8±01). The Bcl-2% and Bcl-2 index in three patients with AML evolved from MDS (57.4±17.9 and 85.1±62.4) were similar to values for seven patients with de novo AML (63.0±10.0, 98.4±29.8) and significantly higher than values for other groups. Bcl-2% showed relative increments with time or disease progression (range, 21–273%; 11 of 18 sequential biopsies from six of ten MDS patients), which was not clearly altered by G-CSF therapy (four of six patients with, two of four patients without treatment). Conclusions: bcl-2 expression by EMPs (in both proportion and absolute number) correlated with initial MDS stage, progressed over time independent of G-CSF therapy, and was associated with evolution to AML. These data provide support for the hypothesis that MDS progression is related to accumulation of immature myeloid cells with increased bcl-2 expression and decreased apoptosis.

Multicentric Epithelioid Angiosarcoma of the Bone

ABSTRACT: Epithelioid angiosarcoma of the bone represents a challenging diagnosis by bone marrow biopsy. We present a case of a multicentric high grade angiosarcoma of the bone with epithelioid features. On the basis of the clinical presentation, the radiological findings, and the appearance of loosely clustered tumor cells detected in the initial bone marrow biopsy, the main differential diagnoses considered were a poorly differentiated non-secretory multiple myeloma and metastatic carcinoma. Subsequent morphologic, immunohistochemical and electron microscopic examination of tissue samples clarified the nature of the tumor as epithelioid angiosarcoma. We discuss potential pitfalls in clinical and morphological diagnosis. The strong reactivity of the tumor cells with the nonspecific but ubiquitous mesenchymal marker vimentin in similar cases should direct early attention to the rare malignant bone tumor, epithelioid angiosarcoma, with subsequent confirmation of this diagnosis with specific immunohistochemical endothelial cell markers and/or electron microscopy.