Bone marrow features improve prognostic efficiency in multivariate risk classification of chronic-phase Ph(1+) chronic myelogenous leukemia: a multicenter trial

Myelofibrosis at diagnosis is associated with the failure of treatment-free remission in CML patients

The management of patients with chronic myeloid leukemia (CML) has been revolutionized by the introduction of tyrosine kinase inhibitors (TKIs), which induce deep molecular responses so that treatment can eventually be discontinued, leading to treatment-free remission (TFR) in a subset of patients. Unfortunately, leukemic stem cells (LSCs) often persist and a fraction of these can again expand in about half of patients that attempt TKI discontinuation. In this study, we show that presence of myelofibrosis (MF) at the time of diagnosis is a factor associating with TFR failure. Fibrotic transformation is governed by the action of several cytokines, and interestingly, some of them have also been described to support LSC persistence. At the cellular level, these could be produced by both malignant cells and by components of the bone marrow (BM) niche, including megakaryocytes (MKs) and mesenchymal stromal cells (MSCs). In our cohort of 57 patients, around 40% presented with MF at diagnosis and the number of blasts in the peripheral blood and BM was significantly elevated in patients with higher grade of MF. Employing a CML transgenic mouse model, we could observe higher levels of alpha-smooth muscle actin (α-SMA) in the BM when compared to control mice. Short-term treatment with the TKI nilotinib, efficiently reduced spleen weight and BCR::ABL1 mRNA levels, while α-SMA expression was only partially reduced. Interestingly, the number of MKs was increased in the spleen of CML mice and elevated in both BM and spleen upon nilotinib treatment. Analysis of human CML-vs healthy donor (HD)-derived MSCs showed an altered expression of gene signatures reflecting fibrosis as well as hematopoietic support, thus suggesting MSCs as a potential player in these two processes. Finally, in our cohort, 12 patients qualified for TKI discontinuation, and here we observed that all patients who failed TFR had BM fibrosis at diagnosis, whereas this was only the case in 25% of patients with achieved TFR, further supporting the link between fibrosis and LSC persistence.

Therapy Resistance and Disease Progression in CML: Mechanistic Links and Therapeutic Strategies

PURPOSE OF REVIEW

Despite the adoption of tyrosine kinases inhibitors (TKIs) as molecular targeted therapy in chronic myeloid leukemia, some patients do not respond to treatment and even experience disease progression. This review aims to give a broad summary of advances in understanding of the mechanisms of therapy resistance, as well as management strategies that may overcome or prevent the emergence of drug resistance. Ultimately, the goal of therapy is the cure of CML, which will also require an increased understanding of the leukemia stem cell (LSC).

RECENT FINDINGS

Resistance to tyrosine kinase inhibitors stems from a range of possible causes. Mutations of the BCR-ABL1 fusion oncoprotein have been well-studied. Other causes range from cell-intrinsic factors, such as the inherent resistance of primitive stem cells to drug treatment, to mechanisms extrinsic to the leukemic compartment that help CML cells evade apoptosis. There exists heterogeneity in TKI response among different hematopoietic populations in CML. The abundances of these TKI-sensitive and TKI-insensitive populations differ from patient to patient and contribute to response heterogeneity. It is becoming clear that targeting the BCR-ABL1 kinase through TKIs is only one part of the equation, and TKI usage alone may not cure the majority of patients with CML. Considerable effort should be devoted to targeting the BCR-ABL1-independent mechanisms of resistance and persistence of CML LSCs.

Myelodysplastic Syndromes with Bone Marrow Fibrosis: An Update

Myelodysplastic syndrome (MDS) is a diverse hematological malignancy with a wide spectrum of presentations and implications. Treatment strategies for patients with MDS heavily rely on prognostic scoring systems, such as the revised international prognostic scoring system (IPSS-R). Bone marrow fibrosis (BMF) has been identified as an independent risk factor for poor survival in patients with MDS, irrespective of the IPSS-R risk category. However, BMF is not widely included in scoring systems and is not always considered by clinicians when making treatment decisions for patients. In this review, we discuss the available literature about the presentation and prognosis of patients with MDS and concurrent BMF. The prognostic impact of BMF should be factored in when deciding on transplant candidacy, especially for intermediate-risk patients.

Novel Usefulness of Krebs von den Lungen 6 (KL-6) with Hemoglobin and Lactate Dehydrogenase for Assessing Bone Marrow Fibrosis

Bone marrow fibrosis (BMF) is manually assessed by reticulin and trichrome stain of bone marrow (BM) biopsy and graded on a semi-quantitative scale. Krebs von den Lungen 6 (KL-6) and Mac-2 binding protein glycosylation isomer (M₂BPGi) are known to be associated with lung and liver fibrosis, respectively. We explored the usefulness of KL-6 and M₂BPGi to assess BMF. A total of 250 patients who underwent BM biopsy with hematologic or non-hematologic diseases were included, and 42 patients with lung and liver diseases were excluded. The patients’ data, including age, sex, diagnosis, white blood cell, hemoglobin (Hb), platelet, and lactate dehydrogenase (LDH) were collected. Measured KL-6 and M₂BPGi levels were compared with reticulin grade (RG) (grade 0–3). KL-6 levels were significantly elevated with an increase in RG, but M₂BPGi did not show a significant difference. Hb, LDH, or KL-6 were independent predictors for BMF (odds ratio: 1.96, 2.26, 2.91, respectively), but showed poor predictive ability (area under the curve [AUC] 0.62, 0.61, 0.60, respectively). The combination of Hb, LDH, and KL-6 showed a significantly improved predictive ability for BMF (AUC 0.73; integrated discrimination improvement 0.057; category-free net reclassification improvement 0.625). This is the first study to evaluate the usefulness of KL-6 for assessing BMF. The combination of Hb, LDH, and KL-6 would be an objective and relevant biomarker approach and be applied to risk stratification for BMF.

Chronic myeloid leukemia stem cells require cell-autonomous pleiotrophin signaling

Tyrosine kinase inhibitors (TKIs) induce molecular remission in the majority of patients with chronic myelogenous leukemia (CML), but the persistence of CML stem cells hinders cure and necessitates indefinite TKI therapy. We report that CML stem cells upregulate the expression of pleiotrophin (PTN) and require cell-autonomous PTN signaling for CML pathogenesis in BCR/ABL+ mice. Constitutive PTN deletion substantially reduced the numbers of CML stem cells capable of initiating CML in vivo. Hematopoietic cell-specific deletion of PTN suppressed CML development in BCR/ABL+ mice, suggesting that cell-autonomous PTN signaling was necessary for CML disease evolution. Mechanistically, PTN promoted CML stem cell survival and TKI resistance via induction of Jun and the unfolded protein response. Human CML cells were also dependent on cell-autonomous PTN signaling, and anti-PTN antibody suppressed human CML colony formation and CML repopulation in vivo. Our results suggest that targeted inhibition of PTN has therapeutic potential to eradicate CML stem cells.

Bone marrow fibrosis at diagnosis predicts survival for primary acute myeloid leukemia

PURPOSE

As a desmoplastic reaction, tissue fibrosis played crucial roles in solid tumor progression, chemo-resistance, and consequently heralded poor clinical outcome. Previous studies implied the effects of marrow fibrosis on prognosis for acute lymphoblastic leukemia were disputable. In this study, we aimed to investigate the potential role of bone marrow fibrosis on clinical survival in acute myeloid leukemia (AML) patients.

METHODS

Bone marrow fibrosis (evaluated as reticulin fiber density, RFD) in bone marrow sections was evaluated at diagnosis via computer technology. Receiver operating characteristic curve (ROC) was used to analyze the predictive value of RFD for relapse and survival status. Kaplan-Meier method was used to estimate survival rates per subgroup between patients with different RFD. Cox proportional hazard regression was used to model the overall survival.

RESULTS

High RFD at diagnosis in bone marrow sections from primary AML might predict early relapse and shorter survival (P = 0.003 and 0.001, respectively). The optimal cutoff value of RFD at diagnosis was determined to be 7.2%. Furthermore, the Kaplan-Meier analysis indicated that patients with high marrow RFD had shorter relapse-free survival (RFS) and overall survival (OS) than patients with low RFD (P = 0.007 and 0.000, respectively). Multivariate analysis suggested that similar with cytogenetics, marrow RFD at diagnosis was an independent prognostic factor for RFS [HR 0.564, 95% confidence interval (CI) 0.338-0.940, P = 0.028] and OS (HR 0.457, 95% CI 0.225-0.929, P = 0.031) in primary AML patients.

CONCLUSIONS

Our data suggest that marrow RFD before treatment should be seemed as prognostic factor in primary AML, it may provide valuable clues for developing new targeted therapy.

Bone marrow fibrosis in myelofibrosis: pathogenesis, prognosis and targeted strategies

Bone marrow fibrosis is a central pathological feature and World Health Organization major diagnostic criterion of myelofibrosis. Although bone marrow fibrosis is seen in a variety of malignant and non-malignant disease states, the deposition of reticulin and collagen fibrosis in the bone marrow of patients with myelofibrosis is believed to be mediated by the myelofibrosis hematopoietic stem/progenitor cell, contributing to an impaired microenvironment favoring malignant over normal hematopoiesis. Increased expression of inflammatory cytokines, lysyl oxidase, transforming growth factor-β, impaired megakaryocyte function, and aberrant JAK-STAT signaling have all been implicated in the pathogenesis of bone marrow fibrosis. A number of studies indicate that bone marrow fibrosis is an adverse prognostic variable in myeloproliferative neoplasms. However, modern myelofibrosis prognostication systems utilized in risk-adapted treatment approaches do not include bone marrow fibrosis as a prognostic variable. The specific effect on bone marrow fibrosis of JAK2 inhibition, and other rationally based therapies currently being evaluated in myelofibrosis, has yet to be fully elucidated. Hematopoietic stem cell transplantation remains the only curative therapeutic approach that reliably results in resolution of bone marrow fibrosis in patients with myelofibrosis. Here we review the pathogenesis, biological consequences, and prognostic impact of bone marrow fibrosis. We discuss the rationale of various anti-fibrogenic treatment strategies targeting the clonal hematopoietic stem/progenitor cell, aberrant signaling pathways, fibrogenic cytokines, and the tumor microenvironment.

Imatinib reduces bone marrow fibrosis and overwhelms the adverse prognostic impact of reticulin formation in patients with chronic myeloid leukaemia

AIMS

Before the era of tyrosine kinase inhibitors (TKIs), the presence of bone marrow fibrosis (MF) in patients with chronic myeloid leukaemia (CML) has been established as a poor prognostic factor. The aim of the present study was to evaluate the effects of imatinib treatment on MF and the prognostic significance of MF at this new era of CML therapy.

METHODS

The study cohort consisted of 135 patients with CML who were exposed to imatinib. The grades of MF pre and post imatinib together with cytogenetic and molecular responses were evaluated.

RESULTS

Severe MF (grade II-III) was observed in 44 (33%) patients prior to imatinib therapy, and in 8 (8%) after 12 months of imatinib treatment (p=0.001). The complete cytogenetic response (CCyR) rates at 12 months did not differ according to the pre-imatinib MF grades, and CCyR rates in patients with grades 0, I, II and III MF were 36/47 (76.5%), 26/33 (78.7%), 12/23 (52.1%) and 7/10 (70%), respectively (p=0.127). There was no significant difference between patients with or without CCyR at 12 months of imatinib regarding grades of MF (p=0.785). The distribution of the major molecular response rates at 18 months according to pre-treatment grades of MF were determined as grade 0 in 38/45 (84.4%), grade I in 21/28 (75%), grade II in 14/21 (66.6%) and grade III in 7/10 (70%) (p=0.112). There was no significant difference in overall survival rates between initial MF mild (grade 0-I) and severe (grade II-III) groups (p=0.278).

CONCLUSIONS

According to our findings, MF regresses with imatinib therapy over time, and the MF grades at diagnosis do not have a negative impact on the responses to imatinib treatment. Therefore, the adverse prognostic impact of the MF among patients with CML seems to disappear in the era of the TKIs.

Spontaneous Soft Tissue Haematomas- A Rare Presentation of Chronic Myeloid Leukemic (CML)

Spontaneous soft tissue haematomas are rarely found in haematological malignancies. Chronic myeloid leukemia (CML) is a myeloproliferative disorder which rarely present with thrombo-haemorrhagic phenomenon. It is a malignant clonal disorder of pleuripotent stem cells that results in increase in myeloid, erythroid and platelets cells in peripheral blood and marked myeloid hyperplasia in bone marrow. It is characterized by the presence of Philadelphia chromosome (Ph) with BCR - ABL 1 fusion gene. This gene is responsible for the formation of 210 KDa chimeric proteins with enhanced tyrosine kinase activity which leads to the abnormal bone marrow cell proliferation and to the clinical and morphologic manifestations of leukemia. Cutaneous and mucous membrane bleeding is common in CML whereas bleeding in deep soft tissue is rarely found because of qualitative and quantitative platelet abnormalities. Here, we report a case of CML (BCR-ABL rearrangement positive) who presented with large haematoma in the anterior as well as posterior compartment of left thigh and treated successfully with hydroxyurea and imatinib.

Risk factors and molecular epidemiology of community-onset extended-spectrum β-lactamase-producing Escherichia coli bacteremia

PURPOSE

Inadequate empirical therapy for severe infections caused by extended-spectrum β-lactamase-producing Escherichia coli (ESBLEC) is associated with poor outcomes. This study was designed to investigate risk factors for community-onset ESBLEC bacteremia at admission to a tertiary care hospital.

MATERIALS AND METHODS

A case-control study was performed that included all episodes of ESBLEC bacteremia in the outpatient department or within 48 hours of admission from January 2005 to March 2009. Data on predisposing factors were collected. The molecular epidemiology of ESBLEC clinical isolates was also determined.

RESULTS

Among 25281 blood cultures, 60 episodes of ESBLEC bacteremia were studied, which accounted for 7% of all E. coli bacteremia at admission. Healthcare-associated infection [odds ratio (OR), 8.3; 95% confidence interval (CI), 2.4-28.7; p=0.001], malignancy (OR, 4.6; 95% CI, 1.3-16.3; p=0.018), urinary tract infection (OR, 139.1; 95% CI, 24.6-788.2; p<0.001), hepatobiliary infection (OR, 79.1; 95% CI, 13.5-463.8; p<0.001), third generation cephalosporin usage during preceding 3 months (OR, 16.4; 95% CI, 2.0-131.8; p=0.008), and severe sepsis/septic shock (OR, 73.7; 95% CI, 12.4-438.5; p<0.001) were determined as independent risk factors for community-onset ESBLEC bacteremia. The most common extended-spectrum β-lactamase (ESBL) gene identified was blaCTX-M-15 (n=31) followed by blaCTX-M-14 (n=23).

CONCLUSION

The most common types of ESBLs in E. coli causing community-onset bacteremia were CTX-M-15 and CTX-M-14 in Korea. By result of decision tree analysis, the empirical use of carbapenems is suggested only for patients with severe sepsis/septic shock, hepatobiliary infection, or healthcare-associated urinary tract infection.

The clinical importance of moderate/severe bone marrow fibrosis in patients with therapy-related myelodysplastic syndromes

The presence of moderate to severe bone marrow (BM) fibrosis has been shown to be an adverse feature in patients with primary myelodysplastic syndromes (MDS). However, the clinical importance of BM fibrosis is not clear in therapy-related MDS. We retrieved all therapy-related MDS (t-MDS) cases (n = 266) diagnosed at our hospital over a 10-year period (2003-2012). Reticulin and trichrome stains were performed in cases in which BM fibrosis was suspected on initial evaluation of hematoxylin and eosin-stained slide. BM fibrosis was graded according to European consensus guidelines, and a score of MF2/MF3 was defined as moderate/severe fibrosis. Moderate/severe BM fibrosis was found in 47 (17%) patients. Compared to 219 patients with no/mild BM fibrosis, the patients with moderate/severe fibrosis presented with severer thrombocytopenia (p = 0.039) and higher numbers of circulating blasts (p = 0.051) but with similar degrees of anemia and neutropenia, transfusion requirements, and similar incidences of hepatosplenomegaly and constitutional symptoms. Histological examination revealed a comparable BM cellularity and BM blast percentage, but markedly increased megakaryocytes (p < 0.001) in the fibrotic group. Although the risk distribution of cytogenetic data was similar according to the New Comprehensive Cytogenetic Scoring criteria, -5 and -17 were more frequently observed in t-MDS with moderate/severe BM fibrosis (p = 0.031 and p = 0.043, respectively). With a median follow-up of 11.5 months, patients with moderate/severe BM fibrosis showed a similar risk of acute myeloid leukemia transformation and a comparable overall survival in univariate and multivariate analyses. Moderate/severe BM fibrosis in patients with t-MDS is associated with certain clinicopathological and genetic features. However, unlike the situation in patients with primary MDS, moderate/severe BM fibrosis does not add additional risk to patients with therapy-related MDS.

The European Consensus on grading of bone marrow fibrosis allows a better prognostication of patients with primary myelofibrosis

We investigated the relationship between the International Prognostic Scoring System of the International Working Group for Myelofibrosis Research and Treatment and the European Consensus on grading of bone marrow fibrosis (MF) in patients with primary myelofibrosis. We compared them in 196 consecutive primary myelofibrosis patients (median follow-up 45.7 months; range 7.4-159). International Prognostic Scoring System classified 42 cases as low risk, 73 as intermediate risk-1, 69 as intermediate risk-2, and 12 as high risk; European Consensus on grading of bone marrow fibrosis classified 83 cases as MF-0, 58 as MF-1, 41 as MF-2, and 14 as MF-3. By the time of the analysis, 30 patients (15.3%) had died. Overall median survival was 3.8 years (95% confidence interval: 3.3-4.3). Multivariate analysis confirmed that both scoring systems independently predicted survival, with hazard ratios similar to those provided by univariate analysis (respectively, 2.40 (95% confidence interval: 1.47-3.91) and 2.58 (95% confidence interval: 1.72-3.89) but the likelihood ratio increased from 19.6 of the International Prognostic Scoring System or 29.0 of the European Consensus on grading of bone MF to 42.3 when both measures were considered together. Analysis of the overall survival curves documented that patients classified as having the most favourable rate with both prognostic scores (ie low risk and MF-0) survive longer than those with only one favourable score (ie low risk but MF >0 or MF-0, but International Prognostic Scoring System >low risk). In contrast, those patients classified as having the most unfavourable rate for both scores (high risk and MF-3) have a shorter survival than those with only one unfavourable score (ie high risk but MF<3 or MF-3, but International Prognostic Scoring System <high risk). In conclusion, our analysis suggests that better prognostication can be achieved in primary myelofibrosis patients when both systems are used together.

Predictors of 12-month outcome in smokers who received bupropion sustained-release for smoking cessation

AIM

To examine heterogeneity in outcome at 12 months following 8 weeks of treatment for smoking cessation with bupropion sustained-release (SR) 150 or 300 mg/day combined with behavioural counselling.

DESIGN, SETTING, PARTICIPANTS

Smokers were recruited from a large healthcare system and then randomized to receive either bupropion SR 150 mg/day (n = 763) or 300 mg/day (n = 761) taken for 8 weeks in combination with either proactive telephone counselling or a tailored mail approach.

MEASUREMENTS AND FINDINGS

A comprehensive set of relevant individual pretreatment and treatment characteristics was included in the analysis. Smoking outcome at 12 months was defined as point-prevalence of any regular self-reported smoking within the 7 days prior to follow-up contact. Classification and regression tree analysis identified subgroups that varied with respect to likelihood of being nonsmokers at 12 months. Seven subgroups were identified among those receiving bupropion SR 150 mg/day (proportion of nonsmokers at 12 months ranged from 13.7% to 43.5%) and eight subgroups among those receiving bupropion SR 300 mg/day (proportion of nonsmokers at 12 months ranged from 9.6% to 51.7%). In the 150-mg/day group, those with the lowest rate reported no previous quit attempt of 1 month or more in duration while those with the highest rate all reported previous quit attempts of 1 month or longer. In the 300 mg/day group, those with the lowest rate had very high levels of dependence while those with the highest rate were more highly educated and smoked at a lower level. Across all subgroups, cost per 12-month quitter ranged from a low of USD302 to a high of USD2,502.

CONCLUSIONS

These results indicate the presence of a substantial amount of variation in outcome following treatment with both dosages of bupropion SR, with substantial cost consequences. Variation in outcome could be reduced by providing treatments tailored to subgroups of individuals who are at exceptionally high risk for smoking following a quit attempt.

Marrow fibrosis and its relevance during imatinib treatment of chronic myeloid leukemia

In chronic myeloid leukemia (CML), imatinib may reverse bone marrow fibrosis (MF). Whether the unfavorable prognosis of MF is also reversed and whether imatinib guarantees against evolution of MF are unclear as yet. Fifty-nine patients with Ph+ CML treated with > or = 400 mg imatinib/day were examined for MF in 6- to 12-month intervals. Imatinib effectively reversed initial MF (P<0.0005). However, during a follow-up period of up to 4.8 years, small foci with abnormal fiber increase (FFI) emerged in 8 of 30 pretreated and 6 of 29 non-pretreated patients. Patients with FFI showed a significantly lower probability of achieving a complete cytogenetic or major molecular response (36 versus 81%; P<0.007). During the further follow up, 57% of patients with FFI but none of the other patients suffered from full-blown MF (P=0.00005). None of the patients with FFI or MF showed a Janus kinase-2 mutation (V617F). Evolutions of FFI and MF were independent significant predictors of imatinib failure (P=0.0031), accelerated phase and death of patients (P=0.0001; multivariate analyses). Imatinib effectively reverses initial MF in CML, but neither eliminates its unfavorable prognosis nor guarantees completely against new evolution of MF.

Myelofibrosis – What’s in a Name?

OBJECTIVE

Myelofibrosis (MF) implies an increase in the bone marrow (BM) fiber content without referring to quantity or quality (reticulin vs. collagen).

METHODS

This review on chronic myeloproliferative disorders is based on initial and sequential BM biopsies, clinical data and follow-up examinations. A semiquantitative grading system for MF approved by a panel of experts was applied.

RESULTS

In chronic myelogenous leukemia, minimal reticulin to advanced collagen MF is detectable at presentation in about 30% of patients. Significant correlations between BM and clinical features, but especially prognosis, are evident. Chronic idiopathic MF includes a prodromal stage showing no or little reticulin and no relevant MF with myeloid metaplasia (MMM). A stepwise evolution is demonstrable and associated with corresponding clinical data. Usually MMM is the diagnostic guideline for this disorder and consequently early stages with accompanying thrombocytosis may clinically mimic essential thrombocythemia. MF of various degrees may be observed in polycythemia vera depending on the progress of disease. Terminal stages (spent phase) reveal overt collagen corresponding with MMM. If diagnosis of essential thrombocythemia regards characteristic BM features, no relevant MF is seen at presentation and transformation into MMM is neglectable for many years.

CONCLUSION

To recognize dynamics of the disease process in chronic myeloproliferative disorders, an easily to reproduce scoring system for MF has been proposed. The clinical diagnosis of MMM does not include initial-early reticulin MF and therefore fails to detect prodromal stages.

Bone marrow histopathology in the diagnosis of chronic myeloproliferative disorders: A forgotten pearl

Histopathology of bone marrow (BM) biopsies plays a crucial role in the interdisciplinary approach to diagnosis and classification of chronic myeloproliferative disorders (CMPDs). Based on careful clinicopathologic studies, BM features are critical determinants that help to predict overall prognosis, to detect complications such as progression to myelofibrosis and blast crisis, and to assess therapy-related changes. A systematic evaluation of BM histopathology allows an objective identification of cases of (true) essential thrombocythemia (ET) and their separation from (false) ET, which often is the prodromal stage of chronic idiopathic myelofibrosis (CIMF). By follow-up examinations that include BM biopsies, the progression of the disease process is unveiled, which is especially important for patients with initial (early) polycythemia vera and prefibrotic CIMF that may require a different therapeutic approach than the full-blown stages. In conclusion, BM biopsy should be considered as major diagnostic tool for evaluation and follow-up of patients enrolled in prospective studies.

A critical reappraisal of the WHO classification of the chronic myeloproliferative disorders

Following the introduction of the WHO classification of chronic myeloproliferative disorders (MPDs), after approximately 5 years, a critical reappraisal appears to be warranted. Retrospective clinico-pathological evaluations conducted in the meantime, as well as the detection of new biomarkers, may aid in testing the validity of these new criteria. Based on a large series of patients with chronic myeloid leukemia (CML), an analysis of bone marrow (BM) features and risk classifications revealed that the fiber content exerted a most important and independent impact on prognosis. This finding was also supported in a prospective randomized study and therefore myelofibrosis should be included in any staging system in CML related to survival. Moreover, it is important to emphasize the dynamics of the disease process in MPDs, especially in polycythemia vera (PV) and chronic idiopathic myelofibrosis (CIMF). Latent-stage PV is difficult to recognize when adhering to the proposed limits for hemoglobin (or red cell mass) without regarding the erythropoietin (EPO) level, endogenous erythroid colonies (EECs) or BM histopathology. Initial PV may firstly present with complications and, when accompanied by a high platelet count, mimics essential thrombocythemia (ET). Consequently, BM morphology and EPO level should be entered as major diagnostic criteria for PV. To document more accurately the progress of disease, a simplified scoring system concerning myelofibrosis has to be included in the histological description of CIMF. The diagnostic guidelines of BM features in ET should be improved because, usually, there is neither a significant proliferation nor left-shifting of the granulo- and erythropoiesis detectable and no relevant increase in reticulin. A comparison of clinical data and BM morphology reveals that biomarkers (EPO, EECs, PRV-1, JAK2) show an overlapping pattern of positivity between the different subtypes of MPDs.

Diagnosis and quantification of bone marrow fibrosis are significantly biased by the pre-staining processing of bone marrow biopsies

AIMS

Marrow fibrosis (MF) is an unfavourable, often lethal complication of haematological neoplasms. Although biopsy technique and staining procedure are standardized, the prestaining processing of bone marrow biopsies (BMBs) varies markedly without any existing data on its significance for the diagnosis of MF.

METHODS AND RESULTS

In this study on 712 BMBs from 296 patients with chronic idiopathic myelofibrosis (CIMF), chronic myeloid leukaemia (CML), or healthy bone marrow, MF was a characteristic complication of CML and CIMF. However, diagnosis and quantification of MF and detection of its prognostic significance were significantly biased by fixation, decalcification, embedding, marrow tissue shrinkage during biopsy processing and the thickness of marrow sections (P < 0.000005). The relevance of these influences was explained by their effect on the marrow volume to which the fibre content was related, whereas the stainability of fibres was not affected. Semiquantitative grading of fibrosis and measurements of fibre density could not be adjusted to various methods of processing of bone marrow biopsies (P < 0.003).

CONCLUSIONS

Evaluations of MF and its prognostic significance should consider the bias due to the prestaining processing of BMBs and the necessity of an adjustment to the thickness of tissue sections and the degree of marrow tissue shrinkage.

Significance of myelofibrosis in early chronic-phase, chronic myelogenous leukemia on imatinib mesylate therapy

BACKGROUND

Myelofibrosis is associated historically with a poor prognosis in patients with chronic myelogenous leukemia (CML). Its significance in the recent era of effective therapy with imatinib mesylate is unknown.

METHODS

The current study evaluated the significance of the degree of pretreatment myelofibrosis on response and survival with imatinib therapy in patients with newly diagnosed CML. The study group comprised 198 patients with newly diagnosed Philadelphia chromosome-positive, chronic-phase CML treated with imatinib mesylate therapy. They were analyzed for the prognostic significance of bone marrow reticulin fibrosis.

RESULTS

Severe reticulin (Grade 3-4) fibrosis was observed in 75 patients (38%): Grade 3 in 46 (23%) patients and Grade 4 in 29 (15%) patients. There was a trend towards a lower incidence of a complete cytogenetic response in patients with Grade 4 reticulin fibrosis (76% vs. 89%; P = 0.07), and a significantly worse survival (estimated 3-year survival rate of 87% vs. 97%; P = 0.04).

CONCLUSIONS

Although the prognostic significance of severe reticulin fibrosis in patients with newly diagnosed CML receiving imatinib therapy was better, 15% of patients with Grade 4 reticulin fibrosis still had a worse outcome.

Treatment intensity significantly influencing fibrosis in bone marrow independently of the cytogenetic response: meta-analysis of the long-term results from two prospective controlled trials on chronic myeloid leukemia

Bone marrow fibrosis (MF) has been shown to indicate therapy failure in Ph(+) chronic myeloid leukemia (CML). However, the results on the development of MF during interferon-alpha therapy of CML are controversial. The significance of the interferon dose has not been considered as yet. In total, 627 bone marrow biopsies taken prospectively from 200 patients with CML recruited in two studies using different doses of interferon-alpha +/- low-dose cytosine arabinoside were examined for MF before and during therapy. The results showed that the risk of MF depended significantly on the interferon-alpha dose applied (P<0.000005). MF progressed during low-dose therapy (3 x 5 x 10(6) IU/week), but was prevented from progression when applying high dose (5 x 10(6) IU/m(2)/per day). MF disappeared when high-dose interferon-alpha was combined with low-dose cytosine arabinoside (P<0.000005). The risk of death markedly increased when MF occurred or progressed (P<0.0009), independent of all other prognostic factors evaluated including the cytogenetic response. In conclusion, the effectiveness of interferon-alpha on MF depends on the treatment intensity. MF reverses when combining high-dose interferon-alpha with low-dose cytosine arabinoside, but progresses when applying low-dose interferon-alpha. MF appears to be a significant early indicator of ineffective therapy in CML.

Imatinib mesylate therapy reduces bone marrow fibrosis in patients with chronic myelogenous leukemia

BACKGROUND

Reticulin-stained bone marrow fibrosis is associated with a poor prognosis in patients with chronic myelogenous leukemia (CML). Resolution of fibrosis with therapy may improve patient outcome.

METHODS

The effect of imatinib therapy on bone marrow fibrosis was evaluated in 40 patients with chronic-phase CML who were treated after interferon-alpha failure.

RESULTS

Thirty-one patients (78%) had severe (Grade 3 or 4) reticulin fibrosis prior to therapy. After imatinib therapy was administered for 3 to > 24 months, fibrosis was reduced by at least 2 grades in 19 of the 31 patients (61%) and by at least 1 grade in 34 patients (85%). There was no correlation noted between reduction of fibrosis and cytogenetic response. However, a reduction in fibrosis was found to correlate with a reduction in bone marrow megakaryocytosis (P = 0.002).

CONCLUSIONS

Treatment with imatinib mesylate appears to reduce CML-associated bone marrow fibrosis in most patients who are treated during the chronic phase of disease. This effect may be independent of the degree of suppression of Philadelphia chromosome-positive cells, and may improve prognosis in patients with CML.

Heterogeneity in 12-month outcome among female and male smokers

AIMS

To examine heterogeneity in outcome following treatment for smoking cessation with combined bupropion SR and behavioral counseling in women and men.

DESIGN, SETTING, PARTICIPANTS

This study included 875 women and 649 men recruited from a large health-care system and randomized to one of four combinations of treatment [two dosage levels of bupropion SR (Zyban, 150 mg and 300 mg) were crossed with two counseling programs of lower and higher intensity to create a four-cell design].

MEASUREMENTS AND FINDINGS

A comprehensive set of relevant individual characteristics prior to treatment and treatment characteristics was included in the analysis. Smoking outcome at 12 months was defined as point-prevalence of any regular smoking within the 7 days prior to follow-up contact. Classification and regression tree analysis identified six subgroups in women that ranged in proportion of non-smokers from 9.8% to 42.9% and six subgroups in men that ranged in proportion of non-smokers from 17.3% to 50.0%.

CONCLUSIONS

These results indicate the presence of a substantial amount of variation in treatment outcome among women and men receiving combined bupropion SR and counseling. Variation in outcome could be reduced by providing treatments tailored to subgroups of individuals who are at exceptionally high risk for smoking following cessation.

Marrow fibrosis, indicator of therapy failure in chronic myeloid leukemia - prospective long-term results from a randomized-controlled trial

Marrow fibrosis (MF) has rarely been considered in therapy studies on chronic myeloid leukemia (CML), and there is a lack of long-term observations on the basis of sequential bone marrow biopsies (BMBs) taken prospectively during the course of disease. A total of 848 BMBs from 400 patients with Ph(+) CML recruited in the German randomized CML study I were examined for MF before and during therapy. In total, 110 patients had been randomized to receive interferon (IFN)-alpha, and 290 to receive chemotherapy (hydroxyurea (HU): 154, busulfan: 136). During IFN-alpha and HU medication, MF was reduced or did not increase for about 2 years. Evolving or progressive MF was an independent and early predictor of therapy failure about 2 years earlier than indicated by changes in the peripheral blood, spleen size, marrow blast count and cytogenetics (P<0.00005), resulting in a significant shortening of the survival times of patients independent of the type of therapy applied including allografting (multivariate analyses; P<0.00005). The analyzed long-term observations strongly indicate that MF is an independent poor prognostic complication of CML, allowing an early prediction of therapy failure. Consideration of the fiber content in marrow may therefore significantly improve the prediction of therapy efficacy and outcome of disease.

Morphological effects of imatinib mesylate (STI571) on the bone marrow and blood of patients with Philadelphia chromosome (Ph) positive chronic myeloid leukaemia

There have been few reports on the morphological findings in patients with chronic myeloid leukaemia (CML) undergoing treatment with imatinib mesylate. We examined morphological changes in the marrow and peripheral blood of 27 patients with chronic phase (CP), accelerated phase (AP) and blastic phase (BP) CML, 3 and 6 months after treatment with imatinib. At 3 months there was a significant clearance of leukaemic cells as evidenced by a complete haematological response (CHR) in the peripheral blood in 25 patients, together with reduced marrow cellularity in 25 (median reduction CP 42%; AP/BP 68%) and a reduction in the number of megakaryocytes (13 of 18 CP: five of six AP/BP; three patients did not have an assessable marrow) with an increase in the amount of normal megakaryopoiesis. After 6 months, there was continued morphological improvement in eight of 17 CP patients (one patient died after 3 months) with continued cytogenetic response (7 out of 15 patients with assessable metaphases had no abnormal Ph+ cells and three had <35% Ph+ cells) and maintenance of haematologic response in all patients. After an initial response to treatment at 3 months in the AP/BP group, with CHR and a reduction in cellularity in all patients, we found morphological evidence of a loss of response to treatment, with an increase in leukaemic cells, as evidenced by loss of CHR in three of nine and an increase in median cellularity in five patients. No patient in this group achieved a complete cytogenetic response. In summary, in CML-CP patients treated with 6 months of imatinib, there was a significant reduction in leukaemic cells as evidenced by a haematolological response in the peripheral blood, together with reduced marrow cellularity, restoration of morphologically normal haemopoiesis and a meaningful cytogenetic response. Maintaining a response to treatment appeared less likely to occur in the AP/BP group patients, especially those who did not achieve any cytogenetic response to treatment.

Evaluating the volume ratio of bone marrow affected by fibrosis: a parameter crucial for the prognostic significance of marrow fibrosis in chronic myeloid leukemia

Marrow fibrosis (MF) is a complication of bone marrow neoplasms that usually impairs quality of life and shortens survival time. Proof and exact quantification of MF is not yet standardized, thus impeding the comparability of results and the evaluation of its prognostic impact. In this study on 360 bone marrow biopsy specimens from 135 patients with either chronic idiopathic myelofibrosis (CIMF) (evaluation group) or chronic myeloid leukemia (CML) (test group), marked differences were detected between six different approaches systematically compared with respect to proof and quantification of MF. A new volumetric approach quantifying the marrow volume affected by fibrosis turned out to be superior to all of the other morphometric methods considering practicability and specificity of results, and superior to a semiquantitative procedure considering sensitivity, precision, and reproducibility (P < 0.00005). The assessment of the marrow volume with fibrosis was the only feature of MF independently influencing the survival time of patients (test group with CML; multivariate analysis, P = 0.0008). We conclude that an approach estimating the marrow volume affected by fibrosis is the method of choice to exactly quantify and prove MF. The loss of marrow volume due to fibrosis appears to be crucial with respect to the prognostic significance of MF in CML. Hum Pathol 34:391-401.

Successful treatment with imatinib mesylate of a CML patient in megakaryoblastic crisis with severe fibrosis

The prognosis of patients with chronic myeloid leukemia in blastic crisis (CML-BC) remains extremely poor, and multiagent chemotherapy regimens commonly used to treat acute leukemia offer only short-term benefits. Therefore, the advent of the novel molecularly targeted anticancer agent imatinib mesylate is a breakthrough in CML therapy. We present a CML patient in megakaryoblastic crisis with severe myelofibrosis, who was treated with imatinib at a dosage of 400 mg/day and achieved complete remission together with a marked regression of myelofibrosis after 1 month. The effect of imatinib on the long-term prognosis remains unclear, although the agent is clearly a promising drug for treating CML-BC even in cases of myelofibrosis.

Treatment of chronic myelogenous leukemia with the tyrosine kinase inhibitor STI571 results in marked regression of bone marrow fibrosis

Morphologic bone marrow changes in patients with BCR-ABL-positive chronic myelogenous leukemia (CML) were investigated during treatment with the tyrosine kinase inhibitor STI571. Bone marrow trephine biopsy specimens from 23 pretreated patients with CML were examined morphologically and by morphometry before and 6 weeks and 3 months after the initiation of STI571 therapy (Glivec, Novartis, Basel, Switzerland). Bone marrow changes during treatment showed a quantitative normalization of erythropoiesis, a marked reduction of granulopoiesis, and a significant decrease in megakaryocytes with the reappearance of normal-sized forms. Furthermore, a significant regression of bone marrow fibrosis was observed in patients with initial fibrosis (P <.000,000,001). These results may expand the profile of STI571 and may offer novel therapeutic possibilities in diseases with bone marrow fibrosis.