Increased Risk of Lymphoid Neoplasms in Patients with Philadelphia Chromosome–Negative Myeloproliferative Neoplasms

From leeches to personalized medicine: evolving concepts in the management of polycythemia vera

Polycythemia vera is a clonal disorder of hematopoietic stem/progenitor cells. It manifests as an expansion of red cell mass. It is the most common chronic myeloproliferative neoplasm. In virtually all cases, it is characterized by a V617F point mutation in JAK2 exon 14 or less common mutations in exon 12. The landmark discovery of the autonomously activated JAK/STAT signaling pathway paved the way for the clinical development of the first target drug, the JAK1 and JAK2 inhibitor ruxolitinib. This is now approved for patients with resistance or intolerance to hydroxyurea. Phlebotomies and hydroxyurea are still the cornerstone of treatment, and aim to prevent the first appearance or recurrence of cardiovascular events that, together with progression to post-polycythemia vera myelofibrosis and leukemia, represent the main causes of death. Interferon-α is an alternative drug and has been shown to induce molecular remissions. It is currently undergoing phase III trials that might eventually lead to its approval for clinical use. The last few years have witnessed important advances towards an accurate early diagnosis of polycythemia vera, greater understanding of its pathogenesis, and improved patient management. This review will focus on the most recent achievements and will aim to unify the different concepts involved in a personalized approach to the patient with polycythemia vera. In spite of many recent advances in the understanding of its pathogenesis and improved disease management, polycythemia vera remains a life-threatening myeloproliferative neoplasm for which there is no cure. This review will present a critical overview of evolving concepts in diagnosis and treatment of this disease.

JAK2 V617F mutation, multiple hematologic and non-hematologic processes: an association?

Background

Population studies showed that patients with JAK2 V617F mutation had increased mortality, and increased risk of any cancer, hematologic cancer, and myeloproliferative disease.

Case presentation

A 68-year-old Asian male with JAK2 V617F mutation developed four different hematologic and non-hematologic neoplastic processes. In 2009, he was diagnosed with stage IA lung adenocarcinoma and also noted to have worsening leukocytosis and thrombocytosis with peak platelet count of 1,054,000/mL). Bone marrow biopsy was consistent with myeloproliferative neoplasm. His monocyte percentage increased in 2011 and met criteria for chronic myelomonocytic leukemia. In 2013, he was admitted for proximal small bowel obstruction, with biopsy confirming stage IE diffuse large B-cell lymphoma. In 2014, a bone marrow biopsy performed for worsening leukocytosis was consistent with acute myeloid leukemia with monocytic differentiation.

Conclusion

This is a rare case depicting the association of JAK2 V617F mutation with myeloproliferative, lymphoproliferative and solid neoplasms.

Coexistence of chronic lymphocytic leukemia and polycythemia vera: a case report and review of the literature

Polycythemia vera is a Philadelphia chromosome-negative myeloproliferative neoplasm. Chronic lymphocytic leukemia is a monoclonal expansion of a CD5+ CD19+ B lymphocytes. Chronic myeloproliferative neoplasms may coexist with indolent B-cell malignant lymphomas of various types. The association of chronic lymphocytic leukemia with polycythemia vera is a rare event with only a few cases of coexistence ever reported. We report a 56-year-old man in whom these two disorders were diagnosed concomitantly. Possible etiopathogenic relationships between both disorders are discussed in this case report.

SIMILAR CASES PUBLISHED

6.

Acute Lymphoblastic Leukemia Arising in CALR Mutated Essential Thrombocythemia

The development of acute lymphoblastic leukemia in an existing myeloproliferative neoplasm is rare with historical cases unable to differentiate between concomitant malignancies or leukemic transformation. Molecular studies of coexisting JAK2 V617F-positive myeloproliferative neoplasms and mature B cell malignancies indicate distinct disease entities arising in myeloid and lymphoid committed hematopoietic progenitor cells, respectively. Mutations of CALR in essential thrombocythemia appear to be associated with a distinct phenotype and a lower risk of thrombosis yet their impact on disease progression is less well defined. The as yet undescribed scenario of pro-B cell acute lymphoblastic leukemia arising in CALR mutated essential thrombocythemia is presented. Intensive treatment for the leukemia allowed for expansion of the original CALR mutated clone. Whether CALR mutations in myeloproliferative neoplasms predispose to the acquisition of additional malignancies, particularly lymphoproliferative disorders, is not yet known.

Coexistence of follicular lymphoma and an unclassifiable myeloproliferative neoplasm in a treatment-naïve patient: A case report

Myeloproliferative neoplasms are associated with lymphoproliferative diseases following the administration of cytotoxic drugs or exposure to radiation, but are rare prior to therapy. The present study reports the case of a 61-year-old female with a history of transient ischemic attack. The patient, who presented with a palpable mass in the epitrochlear area of the left arm, was simultaneously diagnosed with follicular lymphoma and an unclassifiable myeloproliferative neoplasm. Excisional lymph node biopsy revealed stage I follicular lymphoma (grade 1). Laboratory findings demonstrated leukocytosis, erythrocytosis, thrombocytosis and decreased erythropoietin. Biopsy of the bone marrow revealed hypercellularity, with predominance of erythroid cells, and large polylobated megakaryocytes with increased mitotic figures, but no evidence of lymphomatous infiltration. The janus kinase 2 V617F mutation was also detected in the cells derived from the bone marrow specimen. Following local excision of the lymph node in the left epitrochlear area, radiation was delivered to the involved field, at a dose of 24 Gy in 12 fractions. The patient was started on hydroxyurea (1 g twice per day, orally) 2 weeks subsequent to radiotherapy, and was administered 500 mg twice per day as maintenance therapy. At the six-month follow-up, the white blood cell count, hemoglobin levels and platelet count had reduced, and the patient was in a healthy condition. A computed tomography scan of the neck, chest and abdomen indicated no abnormalities. To the best of our knowledge, the present study is the first case report of follicular lymphoma coexisting with an unclassifiable myeloproliferative neoplasm in a previously healthy patient. Molecular and genetic studies are required to further evaluate this infrequent disease association.

Three-fold higher frequency of circulating chronic lymphocytic leukemia-like B-cell clones in patients with Ph-Myeloproliferative neoplasms

Philadelphia chromosome-negative Myeloproliferative neoplasms (Ph-MPN) are accompanied by a markedly increased risk for development of chronic lymphocytic leukemia (CLL) compared to the general population. However, the pattern of onset and the biological characteristics of CLL in patients with coexistent Ph-MPN are highly heterogeneous rendering questionable if the above association reflects a causal relationship between the two disorders or merely represents a random event. By analyzing 82 patients with Ph-MPN and 100 age-matched healthy individuals we demonstrate that MPN patients have an almost threefold higher prevalence of, typically low-count, CLL-like monoclonal B lymphocytosis (MBL) compared to normal adults. The clone size remained unaltered during the disease course and unaffected by the administration of hydroxycarbamide, whereas no patient with Ph-MPN/MBL progressed to CLL during a median follow up of 4 years. Monoclonal B cells in Ph-MPN/MBL patients and normal individuals and in four more patients with coexistence of overt CLL and MPN displayed heterogeneous biological characteristics, while the JAK2V617F mutation was absent in isolated lymphocytes from Ph-MPN patients with coexistence of CLL. Despite its clinical and biological variability, the increased incidence of MBL in Ph-MPN patients along with the one reported for CLL further enforces the notion of a shared pathophysiology among the two malignancies via a common genetic link and/or microenviromental interactions.

Survival of patients with chronic myeloproliferative neoplasms and new primary cancers: a population-based cohort study

BACKGROUND

Patients with chronic myeloproliferative neoplasms are at increased risk of new solid or haematological cancers, but how prognosis is affected in patients with preceding myeloproliferative neoplasms is unclear.

METHODS

We used data from population-based medical databases in Denmark from 1980 to 2011 to compare survival between cancer patients with and without a preceding diagnosis of myeloproliferative neoplasm, matched for age, sex, year of diagnosis, and type of cancer. We assessed outcomes by cancer stage and comorbidities.

FINDINGS

Data were available for 1246 patients with a history of myeloproliferative neoplasms and we matched 5155 patients without a history of myeloproliferative neoplasm for comparison. Among patients with new localised solid cancers, 5-year survival was 49.8% (95% CI 39.1-59.6) for patients with preceding essential thrombocythaemia, 47·9% (42·1-53·4) for those with preceding polycythaemia vera, and 48.0% (34.1-60.7) for those with preceding chronic myeloid leukaemia. The values were 72.4% (68.4-76.0), 63.9% (61.5-66.2), and 74.3% (68.2-79.4), respectively, in matched patients without preceding myeloproliferative neoplasms. The risk of death among patients with a solid tumour and preceding myeloproliferative neoplasm was 1.21-2.28 times higher than in patients without myeloproliferative neoplasms. Excess mortality risk was observed irrespective of whether new cancers were diagnosed within 5 years or 5 years or more after myeloproliferative neoplasm.

INTERPRETATION

Preceding myeloproliferative neoplasm is a predictor for poor outlook in patients who develop new primary cancers.

FUNDING

Lundbeck and Novo Nordisk Foundation Programme for Clinical Research Infrastructure, Danish Cancer Society, and Aarhus University Research Foundation.

Risk and Cause of Death in Patients Diagnosed With Myeloproliferative Neoplasms in Sweden Between 1973 and 2005: A Population-Based Study

PURPOSE

Myeloproliferative neoplasms (MPNs) are associated with a shortened life expectancy. We assessed causes of death in patients with MPN and matched controls using both relative risks and absolute probabilities in the presence of competing risks.

PATIENTS AND METHODS

From Swedish registries, we identified 9,285 patients with MPN and 35,769 matched controls. A flexible parametric model was used to estimate cause-specific hazard ratios (HRs) of death and cumulative incidence functions, each with 95% CIs.

RESULTS

In patients with MPN, the HRs of death from hematologic malignancies and infections were 92.8 (95% CI, 70.0 to 123.1) and 2.7 (95% CI, 2.4 to 3.1), respectively. In patients age 70 to 79 years at diagnosis (the largest patient group), the HRs of death from cardiovascular and cerebrovascular disease were 1.5 (95% CI, 1.4 to 1.7) and 1.5 (95% CI, 1.3 to 1.8), respectively; all were statistically significantly elevated compared with those of controls. In the same age group, no difference was observed in the 10-year probability of death resulting from cardiovascular disease in patients with MPN versus controls (16.8% v 15.2%) or cerebrovascular disease (5.6% v 5.2%). In patients age 50 to 59 years at diagnosis, the 10-year probability of death resulting from cardiovascular and cerebrovascular disease was elevated, 4.2% versus 2.1% and 1.9% versus 0.4%, respectively. Survival in patients with MPN increased over time, mainly because of decreased probabilities of dying as a result of hematologic malignancies, infections, and, in young patients, cardiovascular disease.

CONCLUSION

Patients with MPN had an overall higher mortality rate than that of matched controls, primarily because of hematologic malignancy, infections, and vascular events in younger patients. Evidently, there is still a need for effective disease-modifying agents to improve patient outcomes.

Association of lymphoid malignancies and Philadelphia-chromosome negative myeloproliferative neoplasms: Clinical characteristics, therapy and outcome

The co-occurrence of myeloproliferative and lymphoproliferative neoplasms (MPN/LPN) has been reported, mostly in case reports. The aim of this study was to assess the characteristics and clinical course of the coexistent diseases. Among 9866 patients who presented to our institution from 1960 to 2014, 34 (0.3%) were diagnosed with MPN/LPN. LPN was diagnosed first in 16 patients, second in 15, and at the same time in 3. The time to secondary malignancy was longer when LPN was diagnosed first (119 vs 98 months). Myelofibrosis (41%), polycythemia vera (24%), and essential thrombocythemia (18%) were the most common MPNs, and non-Hodgkin lymphoma (50%) and chronic lymphocytic leukemia (32%) were the most common LPNs. Seventy-three percent of patients treated for MPN and 72% of those treated for LPN achieved a complete response. After a median follow-up from MPN diagnosis of 84 months, 16 patients are alive and 18 died (4 related to MPN and 2 LPN). Coexistent MPN/LPN is a rare event that does not appear to predict worse outcomes. Treatment choice is generally oriented towards controlling the prevalent disease; the other malignancy may influence treatment strategies in selected cases.

Concomitant Myeloproliferative and Lymphoid Neoplasms in Two Patients Positive for JAK2 V617F Mutation. Case Report and Literature Review

The coexistence of both myeloproliferative and lymphoproliferative neoplasms in the same patient is an uncommon finding. We report two patients who presented such an association. The first patient was initially diagnosed with essential thrombocythemia, developing a clinical and haematological picture consistent with chronic lymphocytic leukaemia several years afterwards. The second patient was diagnosed concomitantly with polycythaemia vera and chronic lymphocytic leukaemia. Both patients were positive for the JAK2 V617F mutation. In the first patient the chronic lymphocytic leukaemia was asymptomatic, stage A, and did not require any additional treatment, while the second patient presented with generalized large lymphadenopathy (stage B) and chronic lymphocytic leukaemia-related symptoms, requiring chronic lymphocytic leukaemia-directed treatment. It is unclear whether there is a pathogenetic link between the myeloproliferative and lymphoproliferative diseases encountered in these patients, both being probably the result of random mutations occurring in distinct initiating cells. However, given the higher risk of lymphoproliferative neoplasms development in myeloproliferative neoplasms patients reported in larger studies, the genomic instability characteristic to myeloproliferative neoplasms may play a role in subsequent lymphoproliferative neoplasms occurrence.

A rare case of primary cutaneous follicle centre lymphoma presenting as a giant tumour of the scalp and combined with JAK2V617F positive essential thrombocythaemia

Primary cutaneous follicle centre lymphoma (PCFCL) is a rare cutaneous B cell lymphoma in middle-age adults with excellent prognosis. Here we present a case of a patient with a PCFCL in the form of a giant tumour of the scalp in combination with a myeloproliferative neoplasm, JAK2V617F positive essential thrombocythaemia. This case may be of interest because of the favourable outcome in spite of the large size of the PCFCL, the rare combination with essential thrombocythaemia and because it contributes to discussion on the role of JAK2 mutation in such patients.

A case of minor BCR-ABL1 positive acute lymphoblastic leukemia following essential thrombocythemia and originating from a clone distinct from that harboring the JAK2-V617F mutation

Here we report on a case of Philadelphia chromosome positive B lymphoblastic leukemia (Ph⁺ALL), which developed following a long duration of essential thrombocythemia (ET). A mutational analysis of Janus Kinase 2 (JAK2) revealed that the V617F mutation was present in granulocytes and in hematopoietic stem and progenitor cells (HSPCs), but not in the CD34⁺CD19⁺ population that mostly consists of Ph⁺ALL cells, indicating that this Ph⁺ALL clone did not originate from the ET clone carrying the JAK2-V617F mutation. The minor BCR-ABL1 fusion was detected not only in the CD34⁺CD19⁺ population but also in HSPCs and granulocytes, indicating that the Philadelphia chromosome was acquired in an early hematopoietic stage at least prior to the commitment to B cell development. Upon dasatinib treatment, the minor BCR-ABL1 transcript rapidly disappeared in HSPCs but persisted in the CD34⁺CD19⁺ population. A relapse of Ph⁺ALL occurred nine months later without the disappearance of the minor BCR-ABL1 transcript in the bone marrow cells during the treatment course, suggesting that a resistant Ph⁺ALL clone may have arisen or been selected in the committed B cells rather than in HSPCs. This case report may partly contribute to filling the gap between previous data acquired from mice experiments and the phenomenon in real patients.

Perspectives on the impact of JAK-inhibitor therapy upon inflammation-mediated comorbidities in myelofibrosis and related neoplasms

Chronic inflammation is suggested to contribute to the Philadelphia-chromosome-negative myeloproliferative neoplasm (MPN) disease initiation and progression, as well as the development of premature atherosclerosis and may drive the development of other cancers in MPNs, both nonhematologic and hematologic. The MPN population has a substantial comorbidity burden, including cerebral, cardiovascular, pulmonary, abdominal, renal, metabolic, skeletal, autoimmune, and chronic inflammatory diseases. This review describes the comorbidities associated with MPNs and the potential impact of early intervention with anti-inflammatory and/or immunomodulatory agents such as JAK-inhibitors, statins, and IFN-α to inhibit cancer progression and reduce MPN-associated comorbidity impact. Early intervention may yield a subset of patients who achieve minimal residual disease, thereby likely reducing the comorbidity burden and improving the cost-effective socioeconomic profile.

Coexistence of Chronic Lymphocytic Leukemia and Myeloproliferative Neoplasm

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the Western world. Host immune surveillance caused mainly by the disease itself is speculated to be responsible for high incidence of secondary neoplasms. However, the simultaneous occurrence of CLL and myeloproliferative disorder in the same patient is extremely rare. In the present report, a case of an 81-year-old man who was diagnosed with chronic lymphocytic leukemia and concomitant essential thrombocythemia is presented. We describe the morphologic, immunophenotypic, cytogenetic, and molecular findings in this patient. We also review the current literature.

Inherited predisposition to myeloproliferative neoplasms

Myeloproliferative neoplasms (MPNs) are haematological disorders characterized by an overproduction of mature myeloid cells with a tendency to transform to acute myeloid leukaemia. Clonal proliferation of myeloid progenitor cells is driven by somatically acquired mutations, most notably JAK2 V617F, but there are important features relating to pathogenesis and phenotypic diversity that cannot be explained by acquired mutations alone. In this review we consider what is currently known about the role that inherited factors play in the development and biology of both sporadic and familial forms of MPN. Although most MPN cases appear to be sporadic, familial predisposition has been recognized for many years in a subset of cases and epidemiological studies have indicated the presence of common susceptibility alleles. Currently the JAK2 46/1 haplotype (also referred to as 'GGCC') is the strongest known predisposition factor for sporadic MPNs carrying a JAK2 V617F mutation, explaining a large proportion of the heritability of this disorder. Less is known about what genetic variants predispose to MPNs that lack JAK2 V617F, but there have been recent reports of interesting associations in biologically plausible candidates, and more loci are set to emerge with the application of systematic genome-wide association methodologies. Several highly penetrant predisposition variants that affect erythropoietin signalling, thrombopoietin signalling or oxygen sensing have been characterized in families with nonclonal hereditary erythrocytosis or thrombocytosis, but much less is known about familial predisposition to true clonal MPN. The heterogeneous pattern of inheritance and presumed genetic heterogeneity in these families makes analysis difficult, but whole exome or genome sequencing should provide novel insights into these elusive disorders.

Development of JAK2V617F-positive polycythemia vera after chemotherapy-induced remission of primary central nervous system diffuse large B cell non-Hodgkin's lymphoma: a case report and review of the literature

The coexistence or the development of Philadelphia chromosome-negative myeloproliferative neoplasms after a lymphoproliferative disease in the same patient is an extremely rare event. We report the case of a 72-year-old man who developed JAK2V617F polycythemia vera 3 years after the diagnosis and treatment of primary diffuse large B cell non-Hodgkin's lymphoma of the central nervous system. We also review the literature regarding the pathogenesis underlying the association of myeloproliferative and lymphoproliferative chronic disorders.

Chronic inflammation as a promotor of mutagenesis in essential thrombocythemia, polycythemia vera and myelofibrosis. A human inflammation model for cancer development?

The Philadelphia-negative chronic myeloproliferative neoplasms (MPNs) are acquired stem cell neoplasms, in which a stem cell lesion induces an autonomous proliferative advantage. In addition to the JAK2V617 mutation several other mutations have been described. Recently chronic inflammation has been proposed as a trigger and driver of clonal evolution in MPNs. Herein, it is hypothesized that sustained inflammation may elicit the stem cell insult by inducing a state of chronic oxidative stress with elevated levels of reactive oxygen species (ROS) in the bone marrow, thereby creating a high-risk microenvironment for induction of mutations due to the persistent inflammation-induced oxidative damage to DNA in hematopoietic cells. Alterations in the epigenome induced by the chronic inflammatory drive may likely elicit a "epigenetic switch" promoting persistent inflammation. The perspectives of chronic inflammation as the driver of mutagenesis in MPNs are discussed, including early intervention with interferon-alpha2 and potent anti-inflammatory agents (e.g. JAK1-2 inhibitors, histone deacetylase inhibitors, DNA-hypomethylators and statins) to disrupt the self-perpetuating chronic inflammation state and accordingly eliminating a potential trigger of clonal evolution and disease progression with myelofibrotic and leukemic transformation.

JAK2-V617F-mediated signalling is dependent on lipid rafts and statins inhibit JAK2-V617F-dependent cell growth

Aberrant JAK2 signalling plays an important role in the aetiology of myeloproliferative neoplasms (MPNs). JAK2 inhibitors, however, do not readily eliminate neoplastic MPN cells and thus do not induce patient remission. Further understanding JAK2 signalling in MPNs may uncover novel avenues for therapeutic intervention. Recent work has suggested a potential role for cellular cholesterol in the activation of JAK2 by the erythropoietin receptor and in the development of an MPN-like disorder in mice. Our study demonstrates for the first time that the MPN-associated JAK2-V617F kinase localizes to lipid rafts and that JAK2-V617F-dependent signalling is inhibited by lipid raft disrupting agents, which target membrane cholesterol, a critical component of rafts. We also show for the first time that statins, 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors, widely used to treat hypercholesterolaemia, induce apoptosis and inhibit JAK2-V617F-dependent cell growth. These cells are more sensitive to statin treatment than non-JAK2-V617F-dependent cells. Importantly, statin treatment inhibited erythropoietin-independent erythroid colony formation of primary cells from MPN patients, but had no effect on erythroid colony formation from healthy individuals. Our study is the first to demonstrate that JAK2-V617F signalling is dependent on lipid rafts and that statins may be effective in a potential therapeutic approach for MPNs.

A polymorphism in the XPD gene predisposes to leukemic transformation and new nonmyeloid malignancies in essential thrombocythemia and polycythemia vera

Patients with essential thrombocythemia (ET) and polycythemia vera (PV) have an increased incidence of acute myeloid leukemia and new nonhematologic malignancies compared with the general population. However, information on the factors determining the risk for such complications is limited. In the present study, we investigated whether constitutional genetic variations in DNA repair predispose to leukemic transformation and new nonmyeloid neoplasias in patients with ET and PV. Case-control studies for predisposition to both types of malignancies were nested in a cohort of 422 subjects diagnosed with ET or PV during the period 1973-2010 in several institutions in Spain. A total of 64 incidence cases of leukemia and 50 cases of primary nonmyeloid cancers were accrued. At conditional regression analysis, the Gln/Gln genotype in the XPD codon 751 showed the strongest association with both leukemic transformation (odds ratio [OR] = 4.9; 95% confidence interval [95% CI], 2.0-12) and development of nonmyeloid malignancies (OR = 4.2; 95% CI, 1.5-12). Additional predictive factors were exposure to cytoreductive agents for leukemic transformation (OR = 3.5; 95% CI, 2.0-6.2) and age for nonmyeloid malignancies (OR = 2.0; 95% CI, 1.4-2.8). These findings provide further evidence about the contribution of inherited genetic variations to the pathogenesis and clinical course of myeloproliferative neoplasms.

Perspectives on chronic inflammation in essential thrombocythemia, polycythemia vera, and myelofibrosis: is chronic inflammation a trigger and driver of clonal evolution and development of accelerated atherosclerosis and second cancer?

The morbidity and mortality of patients with the chronic Philadelphia-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia, polycythemia vera, and primary myelofibrosis are mainly caused by cardiovascular diseases, thrombohemorrhagic complications, and bone marrow failure because of myelofibrosis and leukemic transformation. In the general population, chronic inflammation is considered of major importance for the development of atherosclerosis and cancer. MPNs are characterized by a state of chronic inflammation, which is proposed to be the common denominator for the development of “premature atherosclerosis,” clonal evolution, and second cancer in patients with MPNs. Chronic inflammation may both initiate clonal evolution and catalyze its expansion from early disease stage to the myelofibrotic burnt-out phase. Furthermore, chronic inflammation may also add to the severity of cardiovascular disease burden by accelerating the development of atherosclerosis, which is well described and recognized in other chronic inflammatory diseases. A link between chronic inflammation, atherosclerosis, and second cancer in MPNs favors early intervention at the time of diagnosis (statins and interferon-α2), the aims being to dampen chronic inflammation and clonal evolution and thereby also diminish concurrent disease-mediated chronic inflammation and its consequences (accelerated atherosclerosis and second cancer).

The coexistence of chronic lymphocytic leukemia and myeloproliperative neoplasms: a retrospective multicentric GIMEMA experience

Although the coexistence of chronic lymphocytic leukemia (CLL) and myeloproliferative neoplasms (MPN) has been sporadically reported in the literature, no systematic studies on this disease association are available. We retrospectively analyzed 46 patients affected by CLL/MPN referred by 15 Italian GIMEMA centers. The aim of this retrospective multicenter study was to define the following: clinico-biological characteristics, possible familiarity, clinical course of both diseases, and influence of MPN chemotherapy on the course of CLL. Among 46 patients, 30 patients were males, 16 patients were females; median age was 71 years. Only one case had familiar CLL. Myeloproliferative disorders consisted of essential thrombocytemia in 18 cases, polycythemia vera in 10 cases, chronic myeloid leukemia in 9 cases, primary myelofibrosis in 6 cases, and MPN/myelodysplastic syndrome in 3 cases. The lymphoproliferative disorder was diagnosed as monoclonal B-cell lymphocytosis in 8 patients and as Binet Stage A CLL in 38 patients. After a median follow-up of 49 months, 9 patients experienced progressive CLL and only 6 patients required treatment after a median of 57.5 months. The biological profile confirmed a subset of low-risk CLL. Twenty patients received chemotherapy for MPN without influence on the course of CLL: lymphocyte counts remained unchanged after 3, 6, and 12 months of treatment. This series is the largest so far reported in literature. The diagnosis of concomitant CLL/MPN is a rare event and lymphoproliferative disorders present a clinical indolent course with a low-risk biological profile. MPN therapy does not interfere with the prognosis of patients with CLL.

Chronic myeloproliferative neoplasms and subsequent cancer risk: a Danish population-based cohort study

Patients with chronic myeloproliferative neoplasms, including essential thrombocythemia (ET), polycythemia vera (PV), and chronic myeloid leukemia (CML), are at increased risk of new hematologic malignancies, but their risk of nonhematologic malignancies remains unknown. In the present study, we assessed the risk of both types of malignancies after an ET, PV, or CML diagnosis. We linked 2 population-based nationwide registries, the Danish National Registry of Patients, covering all Danish hospitals and the Danish Cancer Registry, and assessed subsequent cancer risk in a cohort of all 7229 patients diagnosed with a chronic myeloproliferative neoplasm during 1977-2008. We compared the incidence of subsequent cancer in this cohort with that expected on the basis of cancer incidence in the general population (standardized incidence ratio). Overall, ET, PV, and CML patients were at increased risk of developing both new hematologic and nonhematologic cancers. The standardized incidence ratio for developing a nonhematologic cancer was 1.2 (95% confidence interval [95% CI]): 1.0-1.4) for patients with ET, 1.4 (95% CI: 1.3-1.5) for patients with PV, and 1.6 (95% CI: 1.3-2.0) for patients with CML. We conclude that patients with chronic myeloproliferative neoplasms are at increased risk of developing a new malignant disease.

Increased risk of lymphoid neoplasm in patients with myeloproliferative neoplasm: a study of 1,915 patients

Within a cohort of 1,915 consecutive patients with myeloproliferative neoplasm followed for a median time of 5.2 years (range 0-33.3), we investigated the occurrence of lymphoid neoplasm with the aim of defining this risk and to investigate the role of genetic predisposing factors. We identified 22 patients with myeloproliferative neoplasm who developed lymphoid neoplasm over their lifetime. We found that the risk of developing lymphoid neoplasm was 2.79-fold higher (95% CI, 1.80-4.33; P<0.001) than that of the general Italian population. A tag SNP surrogate for JAK2 GGCC haplotype was used to clarify a potential correlation between lymphoid-myeloid neoplasm occurrence and this genetic predisposing factor. As we did not find any difference in GGCC haplotype frequency between patients with both myeloid and lymphoid neoplasm and patients with myeloid neoplasm, JAK2 GGCC haplotype should not be considered a genetic predisposing factor. No difference in familial clustering was observed between the two groups.