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The Cochrane Database of Systematic... Apr 2013Polycythaemia vera and essential thrombocythaemia are chronic Philadelphia-negative myeloproliferative neoplasms that increase the risk of arterial and venous... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Polycythaemia vera and essential thrombocythaemia are chronic Philadelphia-negative myeloproliferative neoplasms that increase the risk of arterial and venous thrombosis, as well as bleeding. In addition to the different therapeutic strategies available, an antiplatelet drug is often used to reduce thrombotic risk.
OBJECTIVES
To quantify the benefit and harm of antiplatelet drugs for long-term primary and secondary prophylaxis of arterial and venous thrombotic events in patients with polycythaemia vera or essential thrombocythaemia.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), The Cochrane Library (Issue 1 2012), MEDLINE (1966 to 2012), and EMBASE (1980 to 2012), as well as online registers of ongoing trials and conference proceedings. The date of the last search was October 2012.
SELECTION CRITERIA
We included all randomised controlled trials (RCTs) comparing long-term (>6 months) use of an antiplatelet drug versus placebo or no treatment in participants with polycythaemia vera or essential thrombocythaemia, as diagnosed by established international criteria, with data for at least one of the selected outcomes.
DATA COLLECTION AND ANALYSIS
Using a pre-defined extraction form, two review authors independently screened results, extracted data, and assessed quality. We planned to analyse the following outcomes: mortality from arterial and venous thrombotic events (primary efficacy outcome), mortality from bleeding episodes (primary safety outcome), fatal and non-fatal arterial thrombotic events, fatal and non-fatal venous thrombotic events, micro-circulation events, transient neurological and ocular manifestations, major and minor bleeding episodes, and all-cause mortality and any adverse events. We based quantitative analysis of outcome data on an intention-to-treat principle. We used the pooled odds ratio (OR) with 95% confidence interval (CI) with a fixed-effect model (Mantel-Haenszel) to estimate the overall treatment effect.
MAIN RESULTS
We identified no new studies from the updated searches. We included in this review two RCTs for a total of 630 participants. Both RCTs included participants with an established diagnosis of polycythaemia vera and with no clear indication or contraindication to aspirin therapy. We judged both studies to be of moderate quality. Published data from both studies were insufficient for a time-to-event data analysis and for some of the primary and secondary outcomes that we planned. The use of low-dose aspirin, compared with placebo, was associated with a lower risk of fatal thrombotic events (although this benefit was not statistically significant (OR 0.20, 95% CI 0.03 to 1.14; P = 0.07). No data on mortality from bleeding episodes were available. A non-significant benefit of aspirin was shown for all-cause mortality (OR 0.46, 95% CI 0.21 to 1.01; P = 0.05). No increase in the risk of major bleeding was reported in participants taking aspirin compared with those given placebo (OR 0.99, 95% CI 0.23 to 4.36; P = 0.99), and a non-significant increase with aspirin treatment was shown for minor bleeding (OR 1.85, 95% CI 0.90 to 3.79; P = 0.09). No published studies have reported findings in participants with essential thrombocythaemia or in the study of other antiplatelet drugs.
AUTHORS' CONCLUSIONS
For patients with polycythaemia vera who have no clear indication or contraindication to aspirin therapy, available evidence suggests that the use of low-dose aspirin, when compared with no treatment, is associated with a statistically non-significant reduction in the risk of fatal thrombotic events and all-cause mortality, without an increased risk of major bleeding.
Topics: Anticoagulants; Aspirin; Humans; Platelet Aggregation Inhibitors; Polycythemia Vera; Randomized Controlled Trials as Topic; Thrombocythemia, Essential; Thrombosis
PubMed: 23633335
DOI: 10.1002/14651858.CD006503.pub3 -
Blood Advances May 2024Cytoreductive therapy is not routinely recommended for younger patients with polycythemia vera (PV) due to concern that treatment toxicity may outweigh therapeutic... (Meta-Analysis)
Meta-Analysis
Cytoreductive therapy is not routinely recommended for younger patients with polycythemia vera (PV) due to concern that treatment toxicity may outweigh therapeutic benefits. However, no systematic data support this approach. To support objective risk/benefit assessment of cytoreductive drugs in patients with PV aged <60 years (PV<60), this systematic review and meta-analysis was conducted to evaluate toxicity and disease-related complications in PV<60 treated with interferon alfa (rIFN-α) or hydroxyurea (HU). A search of PubMed, Scopus, Web of Science and Embase identified 693 unique studies with relevant keywords, of which 14 met inclusion criteria and were selected for analysis. The weighted average age of patients treated with rIFN-α was 48 years (n = 744 patients; 12 studies) and for HU was 56 years (n = 1397; 8 studies). The weighted average duration of treatment for either drug was 4.5 years. Using a Bayesian hierarchical model, the pooled annual rate of discontinuation due to toxicity was 5.2% for patients receiving rIFN-α (n = 587; 95% confidence interval [CI], 2.2-8.2) and 3.6% for HU (n = 1097; CI, 1-6.2). The average complete hematologic response for rIFN-α and HU was 62% and 52%, respectively. Patients experienced thrombotic events at a pooled annual rate of 0.79% and 1.26%; secondary myelofibrosis at 1.06% and 1.62%; acute myeloid leukemia at 0.14% and 0.26%; and death at 0.87% and 2.65%, respectively. No treatment-related deaths were reported. With acceptable rates of nonfatal toxicity, cytoreductive treatment, particularly with disease-modifying rIFN-α, may benefit PV<60. Future randomized trials prioritizing inclusion of PV<60 are needed to establish a long-term benefit of early cytoreductive treatment in these patients.
Topics: Humans; Polycythemia Vera; Treatment Outcome; Interferon-alpha; Hydroxyurea; Adult; Middle Aged; Cytoreduction Surgical Procedures; Age Factors
PubMed: 38507746
DOI: 10.1182/bloodadvances.2023012459 -
Revue Neurologique Apr 2017High altitude may be a factor associated with cerebral venous thrombosis (CVT). As our knowledge of CVT at high altitude is limited, it was decided to pool such... (Review)
Review
BACKGROUND AND OBJECTIVE
High altitude may be a factor associated with cerebral venous thrombosis (CVT). As our knowledge of CVT at high altitude is limited, it was decided to pool such information from the available case studies to determine whether high altitude can predispose to CVT.
METHODS
A systematic review of the literature was performed for cases reporting CVT at high altitude. Searches of the PubMed database (up to July 2016) were performed for publications, using 'cerebral venous thrombosis' and 'high altitude' as keywords. Cross-referencing was also done to complete the search.
RESULTS
Ultimately, 13 articles were included in our systematic review. The population consisted of 17 patients, predominately male (14/17), with a mean age of 32 (range: 19-47) years. Altitude range was 3000-8200m. Nine patients stayed at high altitude for>2 weeks; the duration of high altitude stay was unknown for the remainder. A hypercoagulable state was found in nine patients: secondary polycythemia in five; protein C deficiency in one; protein S deficiency in one; and factor V Leiden mutations in two. No comorbidities were found in any of these patients.
CONCLUSION
Long-term stays at high altitude in association with a hypercoagulable state - in particular, congenital or acquired thrombophilia - appears to predispose to CVT. The association of CVT with a single exposure to high altitude seems low, but the risk cannot as yet be specifically estimated.
Topics: Adult; Altitude; Blood Coagulation Disorders; Female; Humans; Intracranial Thrombosis; Male; Middle Aged; Neuroimaging; Venous Thrombosis; Young Adult
PubMed: 28038774
DOI: 10.1016/j.neurol.2016.11.004 -
Current Oncology (Toronto, Ont.) Mar 2024Neuroendocrine prostate cancer (NEPC) is a rare subtype of prostate cancer (PCa) that usually results in poor clinical outcomes and may be accompanied by paraneoplastic... (Review)
Review
Neuroendocrine prostate cancer (NEPC) is a rare subtype of prostate cancer (PCa) that usually results in poor clinical outcomes and may be accompanied by paraneoplastic syndromes (PNS). NEPC is becoming more frequent. It can initially manifest as PNS, complicating diagnosis. Therefore, we reviewed the literature on the different PNS associated with NEPC. We systematically reviewed English-language articles from January 2017 to September 2023, identifying 17 studies meeting PRISMA guidelines for NEPC and associated PNS. A total of 17 articles were included in the review. Among these, Cushing's Syndrome (CS) due to ectopic Adrenocorticotropic hormone (ACTH) secretion was the most commonly reported PNS. Other PNS included syndrome of inappropriate Anti-Diuretic Hormone secretion (SIADH), Anti-Hu-mediated chronic intestinal pseudo-obstruction (CIPO), limbic encephalitis, Evans Syndrome, hypercalcemia, dermatomyositis, and polycythemia. Many patients had a history of prostate adenocarcinoma treated with androgen deprivation therapy (ADT) before neuroendocrine features developed. The mean age was 65.5 years, with a maximum survival of 9 months post-diagnosis. NEPC is becoming an increasingly more common subtype of PCa that can result in various PNS. This makes the diagnosis and treatment of NEPC challenging. Further research is crucial to understanding these syndromes and developing standardized, targeted treatments to improve patient survival.
Topics: Male; Humans; Aged; Prostatic Neoplasms; Androgen Antagonists; Paraneoplastic Syndromes
PubMed: 38534956
DOI: 10.3390/curroncol31030123 -
The Cochrane Database of Systematic... Apr 2008Polycythaemia vera and essential thrombocythaemia are chronic Philadelphia-negative myeloproliferative disorders, which increase the risk of arterial and venous... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Polycythaemia vera and essential thrombocythaemia are chronic Philadelphia-negative myeloproliferative disorders, which increase the risk of arterial and venous thrombosis as well as bleeding. In addition to the different therapeutic strategies available, aspirin is often used to prevent platelet aggregation.
OBJECTIVES
To quantify the benefit and harm of antiplatelet drugs for long-term primary and secondary prophylaxis of arterial and venous thrombotic events in patients with polycythaemia vera or essential thrombocythaemia.
SEARCH STRATEGY
Our searched included the CENTRAL (The Cochrane Library, issue 1 2007), MEDLINE (1966 to 2007) and EMBASE (1980 to 2007) databases, online registers of ongoing trials and conference proceedings. The date of the last search was March 2007.
SELECTION CRITERIA
All randomised controlled trials (RCTs) comparing long-term (>6 months) use of an antiplatelet drug versus placebo or no treatment in patients with polycythaemia vera or essential thrombocythaemia, diagnosed by established international criteria, with data for at least one of the selected outcomes, were included.
DATA COLLECTION AND ANALYSIS
Using a predefined extraction form, we collected and analysed the following data where appropriate: mortality from arterial and venous thrombotic events, mortality from bleeding episodes, fatal and non-fatal arterial thrombotic events, fatal and non-fatal venous thrombotic events, micro-circulation events, transient neurological and ocular manifestations, major and minor bleeding episodes, all-cause mortality and any adverse events. We based quantitative analysis of outcome data on an intention-to-treat principle. The overall treatment effect was estimated by the pooled odds ratio (OR) with 95% confidence interval (CI) using a fixed-effect model (Mantel-Haenszel).
MAIN RESULTS
Two RCTs that investigated 630 patients with an established diagnosis of polycythaemia vera, with no clear indication or contraindication to aspirin therapy, were included in this review. The use of aspirin, compared with placebo, was associated with a lower risk of fatal thrombotic events (although this benefit was not statistically significant (OR 0.20, 95% CI 0.03 to 1.14)) and did not increase the risk of major bleeding (OR 0.99, 95% CI 0.23 to 4.36). No studies have been published in patients with essential thrombocythaemia or studying other antiplatelet drugs.
AUTHORS' CONCLUSIONS
The available evidence suggests that the use of aspirin is associated with a statistically non-significant reduction in the risk of fatal thrombotic events, without an increased risk of major bleeding, when compared with no treatment in patients polycythaemia vera who have no clear indication or contraindication to aspirin therapy.
Topics: Anticoagulants; Aspirin; Humans; Platelet Aggregation Inhibitors; Polycythemia Vera; Randomized Controlled Trials as Topic; Thrombocythemia, Essential; Thrombosis
PubMed: 18425953
DOI: 10.1002/14651858.CD006503.pub2 -
Ultrasound in Obstetrics & Gynecology :... Nov 2021Monochorionic twins with twin-twin transfusion syndrome (TTTS) treated with fetoscopic laser photocoagulation (FLP) are at increased risk of neurodevelopmental... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Monochorionic twins with twin-twin transfusion syndrome (TTTS) treated with fetoscopic laser photocoagulation (FLP) are at increased risk of neurodevelopmental impairment (NDI). This meta-analysis aimed to identify the prevalence of and perinatal risk factors for NDI in TTTS survivors treated with FLP.
METHODS
We performed a search in PubMed, EMBASE, Scopus and Web of Science, from inception to 13 February 2021, for studies evaluating perinatal risk factors for NDI in children diagnosed prenatally with TTTS managed by FLP. Data on severity of TTTS at the time of diagnosis, defined according to the Quintero staging system, FLP-related complications and perinatal outcomes were compared between children with a history of TTTS treated with FLP with and those without NDI, which was defined as performance on a cognitive or developmental assessment tool ≥ 2 SD below the mean or a defined motor or sensory disability. A random-effects model was used to pool the mean differences or odds ratios (OR) with the corresponding 95% CIs. Heterogeneity was assessed using the I statistic.
RESULTS
Nine studies with a total of 1499 TTTS survivors were included. The overall incidence of NDI was 14.0% (95% CI, 9.0-18.0%). The occurrence of NDI in TTTS survivors was associated with later gestational age (GA) at FLP (mean difference, 0.94 weeks (95% CI, 0.50-1.38 weeks); P < 0.0001, I = 0%), earlier GA at delivery (mean difference, -1.44 weeks (95% CI, -2.28 to -0.61 weeks); P = 0.0007, I = 49%) and lower birth weight (mean difference, -343.26 g (95% CI, -470.59 to -215.92 g); P < 0.00001, I = 27%). Evaluation of different GA cut-offs showed that preterm birth before 32 weeks was associated with higher risk for NDI later in childhood (OR, 2.25 (95% CI, 1.02-4.94); P = 0.04, I = 35%). No statistically significant difference was found between cases with and those without NDI with respect to Quintero stage of TTTS, recipient or donor status, development of postlaser twin anemia-polycythemia sequence, recurrence of TTTS and incidence of small- for-gestational age or cotwin fetal demise.
CONCLUSIONS
TTTS survivors with later GA at the time of FLP, earlier GA at delivery and lower birth weight are at higher risk of developing NDI. No significant association was found between Quintero stage of TTTS and risk of NDI. Our findings may be helpful for parental counseling and highlight the need for future studies to understand better the risk factors for NDI in TTTS survivors. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
Topics: Diseases in Twins; Female; Fetofetal Transfusion; Fetoscopy; Gestational Age; Humans; Incidence; Laser Coagulation; Neurodevelopmental Disorders; Postoperative Complications; Pregnancy; Pregnancy, Twin; Premature Birth; Risk Factors; Twins
PubMed: 34097320
DOI: 10.1002/uog.23706 -
Circulation Mar 2007More than 140 million people worldwide live >2500 m above sea level. Of them, 80 million live in Asia, and 35 million live in the Andean mountains. This latter region... (Review)
Review
More than 140 million people worldwide live >2500 m above sea level. Of them, 80 million live in Asia, and 35 million live in the Andean mountains. This latter region has its major population density living above 3500 m. The primary objective of the present study is to review the physiology, pathology, pathogenesis, and clinical features of the heart and pulmonary circulation in healthy highlanders and patients with chronic mountain sickness. A systematic review of worldwide literature was undertaken, beginning with the pioneering work done in the Andes several decades ago. Original articles were analyzed in most cases and English abstracts or translations of articles written in Chinese were reviewed. Pulmonary hypertension in healthy highlanders is related to a delayed postnatal remodeling of the distal pulmonary arterial branches. The magnitude of pulmonary hypertension increases with the altitude level and the degree of exercise. There is reversal of pulmonary hypertension after prolonged residence at sea level. Chronic mountain sickness develops when the capacity for altitude adaptation is lost. These patients have moderate to severe pulmonary hypertension with accentuated hypoxemia and exaggerated polycythemia. The clinical picture of chronic mountain sickness differs from subacute mountain sickness and resembles other chronic altitude diseases described in China and Kyrgyzstan. The heart and pulmonary circulation in healthy highlanders have distinct features in comparison with residents at sea level. Chronic mountain sickness is a public health problem in the Andean mountains and other mountainous regions around the world. Therefore, dissemination of preventive and therapeutic measures is essential.
Topics: Adaptation, Physiological; Adolescent; Adult; Aged; Aged, 80 and over; Altitude; Altitude Sickness; Animals; Cardiac Catheterization; Cardiac Output; Cattle; Cattle Diseases; Child; Child, Preschool; China; Chronic Disease; Diagnosis, Differential; Exercise; Female; Heart Ventricles; Humans; Hypertension, Pulmonary; Hypertrophy, Right Ventricular; Hypoxia; Infant; Infant, Newborn; Latin America; Male; Middle Aged; Muscle, Smooth, Vascular; Polycythemia; Pulmonary Artery; Pulmonary Circulation; Pulmonary Heart Disease; Vasodilator Agents; Ventricular Function
PubMed: 17339571
DOI: 10.1161/CIRCULATIONAHA.106.624544 -
The Cochrane Database of Systematic... Jan 2010Hyperviscosity of blood results in increased resistance to blood flow and decreased oxygen delivery. In the neonate, hyperviscosity can cause abnormalities of central... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Hyperviscosity of blood results in increased resistance to blood flow and decreased oxygen delivery. In the neonate, hyperviscosity can cause abnormalities of central nervous system function, hypoglycemia, decreased renal function, cardiorespiratory distress, and coagulation disorders. Hyperviscosity has been reported to be associated with long-term motor and cognitive neurodevelopmental disorders. Blood viscosity exponentially increases when an infant has polycythemia (hematocrit >/= 65%). Partial exchange transfusion (PET) is traditionally used as the method to lower the hematocrit and treat hyperviscosity.
OBJECTIVES
To evaluate the effect of PET on mortality and neurodevelopmental outcome in infants with neonatal polycythemia.
SEARCH STRATEGY
Electronic databases searched included: The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE (1966 to October 2009), EMBASE (1980 to October 2009) and CINAHL (1982 to October 2009).
SELECTION CRITERIA
Randomized controlled clinical trials or quasi-randomized trials comparing partial exchange transfusion to control (non-treatment) in infants with neonatal polycythemia
DATA COLLECTION AND ANALYSIS
Data collection and analysis was performed according to the standards of the Cochrane Neonatal Review Group.
MAIN RESULTS
One study (Kumar 2004) reported no demonstrable effect on the risk of neonatal mortality (RR 5.23, 95% CI 0.66, 41.26).Four studies reported on neurodevelopmental assessment at 18 months or older. The completeness of follow-up differed widely between the studies. Overall, no difference was seen in developmental delay when all trials are analysed based on available cases (typical RR 1.45, 95% CI 0.83 to 2.54) and when only the randomized controlled trials are analysed (typical RR 1.35, 95% CI 0.68 to 2.69). A best case/worst case analysis of developmental delay is consistent with large benefit or harm from PET.Two studies reported on necrotizing enterocolitis (Van der Elst 1980; Black 1985). An increase in the risk of NEC was noted in infants receiving PET (typical RR 11.18, 95% CI 1.49, 83.64; typical RD 0.14, 95% CI 0.05, 0.22). No differences in short-term complications including hypoglycemia (two studies) and thrombocytopenia (one study) were noted.
AUTHORS' CONCLUSIONS
There are no proven clinically significant short or long-term benefits of PET in polycythemic newborn infants who are clinically well or who have minor symptoms related to hyperviscosity. PET may lead to an increase in the risk of NEC. The data regarding developmental follow-up is extremely imprecise due to the large number of surviving infants who were not assessed and, therefore, the true risks and benefits of PET are unclear.
Topics: Blood Viscosity; Blood Volume; Developmental Disabilities; Hematocrit; Humans; Infant; Infant, Newborn; Plasma Substitutes; Polycythemia; Randomized Controlled Trials as Topic
PubMed: 20091569
DOI: 10.1002/14651858.CD005089.pub2 -
Blood Reviews Mar 2008While there is good evidence for a protective effect of aspirin against occlusive vascular events in individuals with arterial disease, its role in preventing venous... (Review)
Review
While there is good evidence for a protective effect of aspirin against occlusive vascular events in individuals with arterial disease, its role in preventing venous thromboembolism (VTE) is unclear. In this article we review the role of aspirin and other antiplatelet drugs in prevention of venous thromboembolism in surgical patients, high risk medical patients requiring aspirin for other reasons, patients with myeloproliferative disorders, long distance travellers and patients receiving treatment with the IMiD class of drugs. Overall, data from the PEP study and Anti-Platelet Trialists' systematic review show that aspirin reduces the risk of VTE by around 25% in high risk surgical patients. Data from retrospective and before/after studies also suggest efficacy in reducing VTE in myeloma patients on IMiD drugs in combination with dexamethasone or chemotherapy. However, there has been no direct comparison with coumarins or heparin to indicate that aspirin is the optimal form of thromboprophylaxis. In patients who require aspirin because of high risk of arterial vascular occlusion (including patients with polycythaemia vera and essential thrombocythaemia), the additional small reduction in VTE risk is an added benefit with no additional risk associated. There is no evidence for a role of aspirin in prevention of travel-related thrombosis. At present there is no clear evidence that aspirin is the drug of choice for the prevention of VTE in any patient group.
Topics: Aspirin; Clinical Trials as Topic; Humans; Platelet Aggregation Inhibitors; Venous Thromboembolism; Venous Thrombosis
PubMed: 18226435
DOI: 10.1016/j.blre.2007.11.001 -
Frontiers in Oncology 2024Large cell neuroendocrine carcinoma (LCNEC) is a rare subtype of prostate cancer. The pathogenesis, clinical manifestation, treatment options, and prognosis are...
BACKGROUND
Large cell neuroendocrine carcinoma (LCNEC) is a rare subtype of prostate cancer. The pathogenesis, clinical manifestation, treatment options, and prognosis are uncertain and underreported.
MATERIALS AND METHODS
A systematic search was conducted in April 2022 through PubMed, Embase, and Cochrane. We reviewed cases of LCNEC developed either from or transformation from prostate adenocarcinoma and summarized the relevant pathophysiological course, treatment options, and outcomes.
RESULTS
A total of 25 patients with a mean age of 70.4 (range 43 87 years old) from 18 studies were included in this review. 13 patients were diagnosed with LCNEC of the prostate. 12 patients were from the transformation of adenocarcinoma post-hormonal therapy treatment. Upon initial diagnosis, patients diagnosed with prostatic LCNEC had a mean serum PSA value of 24.6 ng/ml (range: 0.09-170 ng/ml, median 5.5 ng/ml), while transformation cases were significantly lower at 3.3 ng/ml (range: 0-9.3 ng/ml, median 0.05 ng/ml). The pattern of metastasis closely resembles prostate adenocarcinoma. Six out of twenty-three cases displayed brain metastasis matching the correlation between neuroendocrine tumors and brain metastasis. Three notable paraneoplastic syndromes included Cushings syndrome, dermatomyositis, and polycythemia. Most patients with advanced metastatic disease received conventional platinum-based chemotherapy with a mean survival of 5 months. There was one exception in the transformation cohort with a somatic BRCA2 mutation who was treated with a combination of M6620 and platinum-based chemotherapy with an impressive PFS of 20 months. Patients with pure LCNEC phenotype have worse survival outcomes when compared to those with mixed LCNEC and adenocarcinoma phenotypes. It is unclear whether there is a survival benefit to administering ADT in pure pathologies.
CONCLUSION
LCNEC of the prostate is a rare disease that can occur or transformation from prostatic adenocarcinoma. Most patients present at an advanced stage with poor prognosis and are treated with conventional chemotherapy regimens. Patients who had better outcomes were those who were diagnosed at an early stage and received treatment with surgery or radiation and androgen deprivation therapy (ADT). There was one case with an exceptional outcome that included a treatment regimen of M6620 and chemotherapy.
PubMed: 38515575
DOI: 10.3389/fonc.2024.1341794