Fertility, pregnancy and the management of myeloproliferative disorders

Contemporary management of patients with BCR-ABL1-negative myeloproliferative neoplasms during pregnancy

INTRODUCTION

The management of pregnancy during the course of BCR-ABL1-negative myeloproliferative neoplasms (MPN) is an increasingly relevant problem. This is mostly due to earlier and better diagnosis of MPN together with the trend in modern society toward delaying pregnancy until later life. Areas Covered: The present review aims to provide an overview of the available literature data concerning outcome of pregnancy in MPN. Possible therapeutic modalities are discussed and a management algorithm is suggested. Expert Commentary: Most data are available for women with essential thrombocythemia and we present 793 published pregnancies. Live birth rate is 68.5% with 31.5% miscarriages. Spontaneous abortion is the most frequent complication with 26.5%, followed by stillbirth with 4.8%. Maternal complications are relatively low with 1.8% major thrombotic and 2.4% major bleeding events. In polycythemia vera the situation is clinically more complex and roughly 150 pregnancy reports are available. There is very limited information in primary myelofibrosis with less than 20 reported pregnancies. With active management including control of blood counts, aspirin, low molecular weight heparin and in higher risk cases interferon alpha pregnancy in MPN is manageable with a success rate not far below the normal situation with 80%.

Pregnancy outcomes in myeloproliferative neoplasms: UK prospective cohort study

The reported higher risk of maternal and fetal complications in women with myeloproliferative neoplasms (MPN) poses challenge during pregnancy. A national prospective study of maternal and fetal outcomes of pregnant women with a diagnosis of MPN was undertaken via the United Kingdom Obstetric Surveillance System between January 2010 and December 2012. Fifty-eight women with a diagnosis of MPN were identified; 47 (81%) essential thrombocythaemia, five (9%) polycythaemia vera, five (9%) myelofibrosis and one (2%) MPN-unclassified. There were 58 live births. The incidence of miscarriage was 1·7/100 (95% confidence interval [CI]: 0·04-9·24) and the perinatal mortality rate was 17/1000 (95% CI: 0·44-92·36) live and stillbirths. Incidence of maternal complications was 9% (5/57) pre-eclampsia, 9% (5/57) post-partum haemorrhage and 3·5% (2/57) post-partum haematoma. There were no maternal deaths or thrombotic events. Delivery was induced in 45% (24/53) of women and the Caesarean section rate was 45% (24/53). The majority (85%, 45/53) delivered at term (>37 weeks gestation). Twenty-two percent (12/54) of neonates were below the 10% centile for growth and 13% (7/54) required admission to a neonatal care-unit; there were no neonatal deaths. The findings of this large, UK prospective study suggests women with MPN appear to have successful pregnancies with better outcomes than would be anticipated from the literature.

A systematic review of the fetal safety of interferon alpha

BACKGROUND

Interferon alpha (IFN) is an effective treatment for a variety of conditions including essential thrombocythemia (ET), chronic myelocytic leukemia, Hepatitis B and C. Because these conditions also occur in women of childbearing age who may become pregnant, information regarding the safety of this medication in pregnancy is essential. This systematic review attempts to summarize all published data on outcome of pregnancies exposed to IFN alpha, trying to differentiate between disease effect and drug effect.

METHODS

Reports on the use of IFN alpha in human pregnancy and reports on essential thrombocythemia (ET) without use of any medication in pregnancy were identified by a systematic search of the medical literature. We were able to locate only case reports of IFN alpha exposure in pregnancy, of whom 40 out of 63 were diagnosed with ET. We also collected randomly 71 cases (more cases were available in the literature) that were diagnosed with ET due to different etiologies, but who had not received any medication in pregnancy.

RESULTS

Among the 63 IFN alpha exposures in pregnancy, the mean maternal age was 30±6 years and the mean full term babies' weight was 3096±463 g. Mean gestational age at delivery was 37±3 weeks. There were 55 single and 4 twin pregnancies. No cases of major malformations or stillbirths were reported. There was one case of spontaneous abortion and 13 preterm deliveries (20% of all exposed cases). Among the 71 cases with untreated ET in pregnancy of different etiologies, 46 (65%) had early (within the first 12 weeks of pregnancy) or late (13-20 weeks of gestation) pregnancy loss. There were also 3 cases (4%) of stillbirth and 4 cases (5.6%) of preterm delivery. Only 18 women (25%) delivered healthy term babies.

CONCLUSIONS

The results of our systematic review suggest that IFN-α does not significantly increase the risk of major malformation, miscarriage, stillbirth or preterm delivery above general population rates. It is also possible that IFN-α may have a protective effect against pregnancy loss in cases of ET.

Management of haematological malignancy in pregnancy

The incidence of haematological malignancies in pregnancy ranges from 1 in 1000 to 1 in 10,000. International prospective epidemiology, management and outcome data are important to gain further knowledge of haematological malignancies in pregnancy. The management of haematological malignancies in pregnancy is complex and requires a multidisciplinary approach. The clinician and mother need to address both maternal and fetal well-being. The mother should be provided with the necessary information and support to make informed decisions regarding the pregnancy and disease management. The haematological malignancies are a diverse group with varied presenting features, pathophysiology, treatment options, levels of urgency to commence treatment in pregnancy, effect on maternal and fetal outcome and overall prognosis. We have reviewed the published research in this area, and provide concise up-to-date guidance on the management of haematological malignancies in pregnancy.

Nonmalignant diseases and treatments associated with primary ovarian failure: an expanded role for fertility preservation

Cancer treatments can be detrimental to fertility; recent literature has focused on the efforts of fertility preservation for this patient population. It should be recognized, however, that several nonmalignant medical conditions and therapeutic interventions could be similarly hazardous to fertility. Some of these nonmalignant diseases and their treatments that can adversely impact the reproductive axis are gastrointestinal diseases, rheumatologic disorders, nonmalignant hematologic conditions, neurologic disorders, renal disorders, gynecologic conditions, and metabolic diseases. Their negative effects on reproductive function are only now being appreciated and include impaired ovarian function, endocrine function, or sexual function and inability to carry a pregnancy to term. Complications and comorbidities associated with certain diseases may limit the success of established fertility preservation options. Recent advances in fertility preservation techniques may provide these patients with new options for childbearing. Here, we review several fertility-threatening conditions and treatments, describe current established and experimental fertility preservation options, and present three initiatives that may help minimize the adverse reproductive effects of these medical conditions and treatments by raising awareness of the issues and options: (1) increase awareness among practitioners about the reproductive consequences of specific diseases and treatments, (2) facilitate referral of patients to fertility-sparing or restorative programs, and (3) provide patient education about the risk of infertility at the time of diagnosis before initiation of treatment.

Myeloproliferative disorders in pregnancy

This article reviews pregnancy outcome in women diagnosed with a myeloproliferative neoplasm (MPN), and discusses possible risk markers and the pathogenesis of poor pregnancy outcome. An outline of the key factors regarding the diagnosis and management of MPN in women of reproductive potential is followed by a description of the authors' management strategy for standard and high-risk pregnancy in MPN patients.

How I treat essential thrombocythemia

In the past 5 years we have witnessed significant advances in both the diagnostic process and optimal therapy for patients with essential thrombocythemia (ET). Insights into the underlying molecular mechanisms have been accompanied by the development of new diagnostic tests and by an improved understanding of the relationship between ET and other related myeloproliferative neoplasms, such as polycythemia vera and primary myelofibrosis. In the first part of this review, we describe how recent molecular and histologic studies can be integrated into a streamlined diagnostic process that is applicable to everyday clinical practice. We also address areas of current diagnostic controversy, including heterogeneity within ET and the phenotypic overlap between ET, polycythemia vera, and primary myelofibrosis. In the second part, we provide an overview of our current approach to the treatment of ET, including risk stratification, choice of cytoreductive agent, and a consideration of special situations such as the pregnant or perioperative patient. Areas of controversy discussed include the identification of those at high risk of complications and therapeutic decisions in the younger patient.

Management of Philadelphia negative chronic myeloproliferative disorders in pregnancy

The management of pregnancy in Philadelphia negative chronic myeloproliferative disorders (CMPDs) is an increasingly frequent problem. In the literature, most pregnancies are reported for women with essential thrombocythemia (ET) with about 400 pregnancies in about 200 women. In ET, first trimester abortion is the most frequent complication occurring in about one third of pregnancies. Interestingly, the incidence of maternal complications is relatively low with 3% for major thromboembolic and 2% for major bleeding events. The presence of the Jak2 mutation seems to be an independent predictor of pregnancy complications. Pregnancies in ET should be stratified according to underlying risk factors in low, high and highest risk pregnancies. Women with low risk pregnancies are treated with low-dose aspirin, whereas women with high and higher risk pregnancies may benefit from low-dose aspirin plus interferon alpha +/- low molecular weight heparin throughout pregnancy and at least for six weeks post-partum. In polycythemia vera (PV) there is only very few information on pregnancy outcome with 36 pregnancies reported in the literature. According to these data pregnancy in PV is per se a high risk situation. Accordingly, all women with PV should be treated with low-dose aspirin. Some pregnant PV patients may benefit from a more intensive therapy including interferon alpha +/- low molecular weight heparin throughout pregnancy and at least for six weeks post-partum.

Essential thrombocythemia

Significant progress in our understanding of the molecular pathogenesis of essential thrombocythemia (ET) and the other Philadelphia (Ph) chromosome-negative myeloproliferative disorders (MPDs) has recently been achieved. Unfortunately, the diagnosis of ET still relies on a set of exclusion criteria developed years ago, as recent advances have yet to be evaluated for this purpose. The clinical course of ET is characterized by an increased incidence of thrombotic and hemorrhagic complications and an inherent tendency to progress into myelofibrosis or acute myeloid leukemia (AML). There is concern about undesirable effects of cytoreductive therapy given to prevent vascular events, particularly the risk of accelerating the rate of hematologic transformation. Thus, management involves modification of reversible vascular risk factors and further stratification according to the thrombotic risk. Myelosuppressive agents are not recommended in low-risk patients, whereas controlled studies support the therapeutic value of hydroxyurea (HU) plus aspirin in high-risk cases. Anagrelide or interferon-alpha (IFN-alpha) could be considered as second-line therapy in patients refractory or intolerant of HU. IFN-alpha is preferred in pregnant women.

Polycythemia Vera: Scientific Advances and Current Practice

Polycythemia vera (PV) is a clonal disorder of unknown etiology involving a multipotent hematopoietic progenitor cell that is characterized by the accumulation of phenotypically normal red blood cells, white blood cells, and platelets in the absence of a definable cause; extramedullary hematopoiesis, marrow fibrosis, and, in a few patients, transformation to acute leukemia can also occur. First described in 1892, the cause of the disease remains unknown and no potentially curative therapy other than bone marrow transplantation is currently available. It is commonly held that PV is a rare disorder, when in fact with a minimum incidence of 2.6 per 100,000 it is more common than chronic myelogenous leukemia (CML) and is particularly prevalent in persons of Ashkenazi Jewish ancestry. However, the incidence of PV is not as high as that of erythrocytosis from other causes collectively, which poses a problem in differential diagnosis when PV presents as isolated erythrocytosis. Characteristic features of PV are erythropoietin (Epo)-independent in vitro erythroid colony formation, as well as hypersensitivity to many other hematopoietic growth factors. Recently, a remarkable association between PV and a somatic point mutation of the JAK2 tyrosine kinase (JAK2 V617F) was described. Functional assays have revealed that JAK2 V617F is capable of inducing constitutive STAT5-mediated signaling in vitro, as well as erythrocytosis in vivo in mice. These data suggest that the JAK2 V617F mutation participates in the pathogenesis of PV. In current clinical practice, two different clinical approaches have been used to diagnose PV. One approach requires establishing the presence of absolute erythrocytosis by directly determining the red cell mass (RCM). A second approach utilizes a RCM-independent diagnostic algorithm based on the serum Epo level and bone marrow histology. Screening for JAK2 V617F can now be added to both diagnostic algorithms. However, it is very clear that some patients with classical PV lack the JAK2 V617F mutation, while some patients with other chronic myeloproliferative disorders such as idiopathic myelofibrosis (IMF) and essential thrombocytosis (ET) also express the JAK2 V617F mutation. Therefore, by necessity, any discussion of PV must take into consideration these companion myeloproliferative disorders, and since erythrocytosis is the single clinical feature that sets PV apart from IMF and ET, it is clear that the presence of the JAK2 V617F mutation cannot by itself establish a diagnosis of PV. Phlebotomy remains the mainstay of therapy for PV. In addition, both aspirin and cytoreductive therapy have been employed to control thrombocytosis and in the case of the latter, leukocytosis and extramedullary hematopoiesis as well. Despite recent progress in the field, several important issues remain controversial. In this review, we will present the areas of agreement, but also point out where the authors' personal viewpoints differ.

Pregnancy and its management in the Philadelphia negative myeloproliferative diseases

The myeloproliferative diseases (MPDs) present several therapeutic challenges in patients of childbearing potential. The most extensive literature exists for patients with essential thrombocythaemia, with over 200 pregnancies reported in retrospective case series. Yet there is conflicting data in relation to predicting pregnancy outcome and optimal management strategy. Pregnancy is less frequently reported for polycythaemia vera and myelofibrosis. There is a need for collaboration to further our knowledge in this field. Here, the literature is reviewed in detail and experience of different therapeutic strategies in pregnancy discussed. There is increasing understanding about the pathogenesis of placental dysfunction in inherited thrombophilia and antiphospholipid antibody syndrome pregnancy outcomes in these conditions parallel those reported for MPDs. Furthermore several large studies have influenced pregnancy management in these conditions and, whilst not directly applicable to MPDs, this data have potential to inform treatment protocols. This data are reviewed and a personal management strategy for pregnancy in MPD proposed.

Thrombocythemia and hemoperitoneum after transvaginal oocyte retrieval for in vitro fertilization

OBJECTIVE

To present the first report of massive hemoperitoneum in a case of essential thrombocythemia after transvaginal oocyte retrieval for IVF and review the relevant literature related to the management of patients with this condition.

DESIGN

Case report.

SETTING

Assisted conception unit of a tertiary care university hospital in the United Kingdom.

PATIENT(S)

A 37-year-old woman with essential thrombocythemia who developed massive intra-abdominal bleeding after transvaginal oocyte retrieval for IVF.

INTERVENTION(S)

Emergency laparotomy and right salpingoophorectomy.

RESULT(S)

Resuscitation of the patient.

MAIN OUTCOME MEASURE(S)

Overall management of the patient is discussed.

CONCLUSION(S)

The management of patients with essential thrombocythemia at the childbearing period poses a difficult problem. Fertility may be reduced, and an adverse outcome of pregnancy due to thrombotic or bleeding complications is a matter of concern. A multidisciplinary approach with close and early cooperation with the hematologists before initiation of IVF therapy for patients with essential thrombocythemia is essential. Efforts should be made to reduce the platelet count and assess the platelet function before embarking on IVF, keeping in mind the double jeopardy from bleeding and thrombosis in these cases.

Implications of systemic malignancies on human fertility

Cancer patients have now longer life expectancy due to improved treatment modalities. As the mortality rate decreased and the survival rate increased, the consequences of cancer treatment in terms of impaired fertility became more frequently encountered. The objective of this review is to highlight fertility issues associated with systemic malignancies. Systemic malignancies lead to deterioration of human fertility directly or indirectly as a result of cytotoxic treatment regimens. A variety of measures may be used to decrease the incidence of fertility decline that occurs. Gamete cryopreservation represents a widely accepted method for fertility preservation in cancer patients. In addition, other procedures such as germ cell transplantation and ovarian cryopreservation, which are currently being developed, are expected to make significant contribution in these cases. However, there are some ethical issues that should be considered before offering patients any of these options.

Chronic myeloproliferative disorders

The Philadelphia chromosome-negative chronic myeloproliferative disorders (CMPD), polycythemia vera (PV), essential thrombocythemia (ET) and chronic idiopathic myelofibrosis (IMF), have overlapping clinical features but exhibit different natural histories and different therapeutic requirements. Phenotypic mimicry amongst these disorders and between them and nonclonal hematopoietic disorders, lack of clonal diagnostic markers, lack of understanding of their molecular basis and paucity of controlled, prospective therapeutic trials have made the diagnosis and management of PV, ET and IMF difficult. In Section I, Dr. Jerry Spivak introduces current clinical controversies involving the CMPD, in particular the diagnostic challenges. Two new molecular assays may prove useful in the diagnosis and classification of CMPD. In 2000, the overexpression in PV granulocytes of the mRNA for the neutrophil antigen NBI/CD177, a member of the uPAR/Ly6/CD59 family of plasma membrane proteins, was documented. Overexpression of PRV-1 mRNA appeared to be specific for PV since it was not observed in secondary erythrocytosis. At this time, it appears that overexpression of granulocyte PRV-1 in the presence of an elevated red cell mass supports a diagnosis of PV; absence of PRV-1 expression, however, should not be grounds for excluding PV as a diagnostic possibility. Impaired expression of Mpl, the receptor for thrombopoietin, in platelets and megakaryocytes has been first described in PV, but it has also been observed in some patients with ET and IMF. The biologic basis appears to be either alternative splicing of Mpl mRNA or a single nucleotide polymorphism, both of which involve Mpl exon 2 and both of which lead to impaired posttranslational glycosylation and a dominant negative effect on normal Mpl expression. To date, no Mpl DNA structural abnormality or mutation has been identified in PV, ET or IMF. In Section II, Dr. Tiziano Barbui reviews the best clinical evidence for treatment strategy design in PV and ET. Current recommendations for cytoreductive therapy in PV are still largely similar to those at the end of the PVSG era. Phlebotomy to reduce the red cell mass and keep it at a safe level (hematocrit < 45%) remains the cornerstone of treatment. Venesection is an effective and safe therapy and previous concerns about potential side effects, including severe iron deficiency and an increased tendency to thrombosis or myelofibrosis, were erroneous. Many patients require no other therapy for many years. For others, however, poor compliance to phlebotomy or progressive myeloproliferation, as indicated by increasing splenomegaly or very high leukocyte or platelet counts, may call for the introduction of cytoreductive drugs. In ET, the therapeutic trade-off between reducing thrombotic events and increasing the risk of leukemia with the use of cytoreductive drugs should be approached by patient risk stratification. Thrombotic deaths seem very rare in low-risk ET subjects and there are no data indicating that fatalities can be prevented by starting cytoreductive drugs early. Therefore, withholding chemotherapy might be justifiable in young, asymptomatic ET patients with a platelet count below 1500000/mm(3) and with no additional risk factors for thrombosis. If cardiovascular risk factors together with ET are identified (smoking, obesity, hypertension, hyperlipidemia) it is wise to consider platelet-lowering agents on an individual basis. In Section III, Dr. Gianni Tognoni discusses the role of aspirin therapy in PV based on the recently completed European Collaboration on Low-dose Aspirin in Polycythemia Vera (ECLAP) Study, a multi-country, multicenter project aimed at describing the natural history of PV as well as the efficacy of low-dose aspirin. Aspirin treatment lowered the risk of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke (relative risk 0.41 [95% CI 0.15-1.15], P =.0912). Total and cardiovascular mortality were also reduced by 46% and 59%, respectively. Major bleedings were slightly increased nonsignificnsignificantly by aspirin (relative risk 1.62, 95% CI 0.27-9.71). In Section IV, Dr. Giovanni Barosi reviews our current understanding of the pathophysiology of IMF and, in particular, the contributions of anomalous megakaryocyte proliferation, neoangiogenesis and abnormal CD34(+) stem cell trafficking to disease pathogenesis. The role of newer therapies, such as low-conditioning stem cell transplantation and thalidomide, is discussed in the context of a general treatment strategy for IMF. The results of a Phase II trial of low-dose thalidomide as a single agent in 63 patients with myelofibrosis with meloid metaplasia (MMM) using a dose-escalation design and an overall low dose of the drug (The European Collaboration on MMM) will be presented. Considering only patients who completed 4 weeks of treatment, 31% had a response: this was mostly due to a beneficial effect of thalidomide on patients with transfusion dependent anemia, 39% of whom abolished transfusions, patients with moderate to severe thrombocytopenia, 28% of whom increased their platelet count by more than 50 x 10(9)/L, and patients with the largest splenomegalies, 42% of whom reduced spleen size of more than 2 cm.

Clonal hemopoiesis and risk of thrombosis in young female patients with essential thrombocythemia

OBJECTIVE

Several studies demonstrated a high prevalence of nonrandom X-chromosome inactivation pattern (X-CIP) in essential thrombocythemia (ET). This study explored the incidence of clonal hemopoiesis in myeloid precursors and endogenous erythroid colonies (EECs) in ET patients and its correlation with thrombotic manifestations.

MATERIALS AND METHODS

Clonal analysis of hemopoiesis using X-CIP was performed in 40 female patients with ET. Median age was 40.5 years (range 20-64), and median platelet count at testing time was 700 x 10(9)/L (range 220-1300 x 10(9)/L). Patients older than 65 years were excluded to reduce age-related skewing. Clonality was assessed on neutrophils, platelets, EECs, and bone marrow CD34(+) cells.

RESULTS

Eight (20%) of 40 patients developed thrombosis mainly at diagnosis. Clonal hemopoiesis was found in 17 (42.5%) patients, 15 (37.5%) had polyclonal hemopoiesis, and 8 (20%) were considered uninterpretable due to constitutive skewing. Clonality was confirmed on purified CD34(+) subpopulations from bone marrow, documenting that clonality does not appear lineage-restricted. There were no statistical differences in age at diagnosis, median platelet count at testing time, and length of follow-up. Thrombotic episodes were significantly more frequent in the monoclonal group (p = 0.04, Fisher exact test).

CONCLUSIONS

Young female patients with ET exhibiting a clonal pattern of hemopoiesis by X-CIP analysis are at higher risk for thrombosis. X-CIP analysis may contribute to defining the individual risk leading to appropriate treatment. X-CIP will allow a correct diagnosis in patients with latent myeloproliferative disorders and thrombosis in unusual sites. Clonal hemopoiesis is easily recognized by X-CIP, but its applicability is limited to the female sex and is hampered by the presence of age-related or constitutive skewing.

Current treatment practice for essential thrombocythaemia in adults

Essential thrombocythaemia (ET) is a relatively benign chronic myeloproliferative disorder that occurs primarily in middle-aged patients. Its clinical course is characterised by thomboembolic and, less frequently, by haemorrhagic complications. Life expectancy of ET is generally of normal length and progression to acute leukaemia is a rare event. About one third of all patients are asymptomatic at diagnosis and many of them remain without complications for years. Therefore, the main challenge for treating patients with ET is to select patients who will benefit from a cytoreductive or antiplatelet therapy, because it is doubtful whether the beneficial effects of therapy outweigh the potential hazards in all cases. For this reason a risk stratification in high and low risk ET patients is essential. The treatment of ET has evolved from alkylating agents to hydroxyurea (HU) or pipobroman and more recently to agents such as IFN-alpha and anagrelide. Aspirin as an antiplatelet therapy is also expected to play a part in the treatment of ET. HU is first-line therapy for elderly patients with high risk ET. In young ET patients without ET related complications and a platelet count << 1000 - 1500 x 10(9)/l abstention from cytoreductive therapy or therapy with low-dose aspirin alone seems to be appropriate. The aim of this review is to address the current treatment practice for ET in adults.