Multiparametric MRI to quantify disease and treatment response in mice with myeloproliferative neoplasms.

Histopathology, the standard method to assess BM in hematologic malignancies such as myeloproliferative neoplasms (MPNs), suffers from notable limitations in both research and clinical settings. BM biopsies in patients fail to detect disease heterogeneity, may yield a nondiagnostic sample, and cannot be repeated frequently in clinical oncology. Endpoint histopathology precludes monitoring disease progression and response to therapy in the same mouse over time, missing likely variations among mice. To overcome these shortcomings, we used MRI to measure changes in cellularity, macromolecular constituents, and fat versus hematopoietic cells in BM using diffusion-weighted imaging (DWI), magnetization transfer, and chemical shift-encoded fat imaging. Combining metrics from these imaging parameters revealed dynamic alterations in BM following myeloablative radiation and transplantation. In a mouse MPLW515L BM transplant model of MPN, MRI detected effects of a JAK2 inhibitor, ruxolitinib, within 5 days of initiating treatment and identified differing kinetics of treatment responses in subregions of the tibia. Histopathology validated the MRI results for BM composition and heterogeneity. Anatomic MRI scans also showed reductions in spleen volume during treatment. These findings establish an innovative, clinically translatable MRI approach to quantify spatial and temporal changes in BM in MPN.

VEXAS syndrome.

VEXAS syndrome (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) is a monogenic disease of adulthood caused by somatic mutations in UBA1 in hematopoietic progenitor cells. Patients develop inflammatory and hematologic symptoms. Myeloid-driven autoinflammation and progressive bone marrow failure lead to substantial morbidity and mortality. Effective medical treatments need to be identified. Reports in the current issue of Blood describe novel UBA1 genetic variants, treatment options, and insight into disease pathophysiology. VEXAS syndrome represents a prototype for a new class of diseases.

The value of bone marrow, liver, and spleen imaging in diagnosis, prognostication, and follow-up monitoring of myeloproliferative neoplasms: a systematic review.

BACKGROUND: Diagnostic and treatment response criteria for the JAK2/CALR/MPL mutation-related myeloproliferative neoplasms (MPNs) are largely based on bone marrow (BM) biopsy results. However, these biopsies have several limitations, such as the risk of sampling error. Also, the prognostic impact of BM abnormalities is largely unclear. Although not currently used in clinical practice, imaging techniques might offer additional information. In this review, we investigated the value of BM, liver, and spleen imaging for diagnosis, prognostication, and response monitoring of the JAK2/CALR/MPL mutation-related MPNs (i.e. essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF)). METHODS: A systematic literature search was performed via PubMed, Embase and the Cochrane Library up to 2020 March 26th. Of 5505 identified records, 55 publications met the eligibility criteria (i.e. containing original data on the imaging appearance of BM, spleen, or liver in adult ET, PV, or MF patients, published in a peer-reviewed journal, written in English). RESULTS: Many explorative studies described imaging features, sometimes with comparisons to clinical characteristics. Studies reporting measures of diagnostic accuracy included 1) splenic transient elastography to predict BM fibrosis grade in MF, 2) dynamic contrast-enhanced MRI to discern MF patients from ET patients and healthy controls, and 3) 18-fluorodeoxyglucose PET to detect residual disease after stem cell transplantation in MF. The diagnostic accuracies of radiography and 99mTc-colloid scintigraphy were derived from several other articles. Except for the study on 18-fluorodeoxyglucose PET, we established substantial concerns regarding risk of bias and applicability across these studies, using the QUADAS-2 tool. Three publications described a correlation between imaging results and prognosis, of which one quantified the effect. CONCLUSIONS: Based on current data, MRI (T1-weighted/STIR, Dixon) seems especially promising for the evaluation of BM fat content - and indirectly cellularity/fibrosis - in MF, and possibly for estimating BM cellularity in ET/PV. 18-fluorodeoxyglucose and 18-fluorothymidine PET/CT might be useful for evaluating BM fibrosis, with good reported accuracy of the former for the diagnosis of residual disease. Further research on these and other techniques is warranted to determine their exact value. Future researchers should improve methodology and focus on evaluation of diagnostic accuracy and prognostic implications of results.

Clinical characteristics and brain MRI findings in myeloproliferative neoplasms.

BACKGROUND: Myeloproliferative neoplasms (MPNs) including polycythemia vera (PV) and essential thrombocythemia (ET) have an increased risk of ischemic stroke. However, little is known about brain morphological changes and the cerebral vasculature in MPNs. The aim of the present study is to clarify the prevalence rates of brain infarcts (BIs) on magnetic resonance imaging (MRI) and to assess the detailed clinical and MRI characteristics in those patients. METHODS: We prospectively enrolled patients with MPNs who underwent brain MRI between September 2017 and June 2019. BI patterns were characterized by the numbers and locations of BIs on MRI. RESULTS: A total of 101 patients were included in the present study. BIs were observed in 23 patients (23%). Multiple logistic regression analysis showed that age > 60 years (odds ratio (OR) 7.34, 95% confidence interval (CI) 1.08-49.7, p = .041) and history of thrombosis (OR 40.6, 95% CI 7.97-207, p < .0001) were independently associated with BIs, but not the JAK2V617F mutation. Of the 23 patients with BIs, eight patients (35%) had multiple territorial infarcts, and large vessel involvement was identified in five patients (22%). Two patients had thrombus formation in large vessels. CONCLUSIONS: Among patients with MPNs who underwent MRI, BIs were observed in 23% of patients followed up in our center. Older age and thrombosis history were independently associated with BIs. Some patients with MPNs may present with distinctive MRI findings including multiple territorial infarcts and thrombus formation in large vessels.

Myeloproliferative Neoplasms: A Primer for Radiologists.

The myeloproliferative neoplasms (MPNs) are a heterogeneous group of diseases including polycythemia vera, essential thrombocythemia, and primary myelofibrosis. Knowledge of the radiological and clinical features of MPNs and their associated complications is critical for interpreting radiologists. The purpose of this article is to provide a primer to radiologists summarizing the modern understanding of MPNs from an imaging-based perspective, including common disease-related findings and complications related to hematopoietic cell transplant.

[Brain MRI-findings in Ph - negative myeloproliferative disorders].

Myeloproliferative disorders (MPD) are accompanied by a high proportion of thrombotic complications, which may lead to cerebrovascular disease (CVD). AIM: To describe MRI-findings in patients with Ph - negative MPD and evaluate any cerebrovascular disease. MATERIALS AND METHODS: We included 104 patients with Ph - negative MPD (age varied between 20 and 58) with clinical correlates of cerebrovascular pathology. RESULTS: Brain MRI showed post - stroke lesions in 20% of patients (7 hemispheric infarcts due to thrombotic occlusion of one of the large cerebral arteries, 14 - cortical infarcts). 37 patients (36%) had vascular cerebral lesions. Cerebral venous sinus thrombosis occurred in 5 patients - in 7% (n=3) of patients with polycythemia vera and 5% (n=2) - in patients with essential thrombocythemia. The incidence of vascular cerebral lesions was associated with higher levels of the following: erythrocyte, platelet count, fibrinogen, and with the decrease in fibrinolytic activity, as well. CONCLUSION: The pioneering results of the study include the description and analysis of brain MRI-findings in patients with Ph - negative MPD. The underlying mechanisms of cerebrovascular pathology in these patients are associated with certain blood alterations (particularly, hemorheology) which present a major risk factor.

Imaging features of myeloproliferative neoplasms.

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of haematological disorders including polycythaemia vera (PV), essential thrombocythaemia (ET), primary myelofibrosis (PMF), and chronic myeloid leukaemia (CML). These disorders show large overlap in genetic and clinical presentations, and can have many different imaging manifestations. Unusual thromboses, embolic events throughout the systemic or pulmonary vasculature, or osseous findings can often be clues to the underlying disease. There is limited literature about the imaging features of these disorders, and this may result in under-diagnosis. Multiple treatments are available for symptom control, and the development of multiple new pharmacological inhibitors has significantly improved morbidity and prognosis. Knowledge of these conditions may enable the radiologist to suggest an MPN as a possible underlying cause for certain imaging findings, particularly unexplained splanchnic venous thrombosis, i.e. in the absence of chronic liver disease or pancreatitis. The aim of the present review is to outline using examples the different categories of MPN and illustrate the variety of radiological findings associated with these diseases.

Skeletal "Superscan" on 18F-Choline PET/CT: Cases of Myeloproliferative Disease.

We describe 2 cases of skeletal "superscan" with F-choline PET/CT in prostate cancer (PCa) patients. Both cases demonstrated diffuse skeletal involvement besides their primary prostate tumor. The first impression was that this presentation would be related to diffuse tumoral skeletal invasion by PCa as often seen in Tc-MDP bone scintigraphy. In both cases, the bone involvement was shown to be caused by hematological disease (polycythemia vera and chronic myelomonocytic leukemia), demonstrating the importance of also considering the presence of myeloproliferative syndromes when presented with diffuse bone disease on choline PET/CT performed in PCa patients.

Extramedullary Hematopoiesis: Cytomorphologic, Histologic, and Radiologic Findings in Sixteen Cases.

BACKGROUND: We report a case series of extramedullary hematopoiesis (EMH) diagnosed from the fine needle aspiration (FNA) procedure. Unanticipated EMH is a markedly rare diagnosis that typically presents as a solitary mass of undetermined significance. As such, knowledge of cytopathologic characteristics as well as clinical and radiologic correlates of EMH is paramount. METHOD AND MATERIAL: A total of 16 EMH cytopathologic cases were seen at the Johns Hopkins Hospital in the past 22 years. RESULTS: Median age at diagnosis was 61 years and there was no gender bias (male-to-female ratio: 1:1). Presenting signs and symptoms varied widely, from incidental radiographic findings to hemiparesis. Likewise, presumptive clinical diagnoses in 11 of the 16 cases were benign and the other 5 were considered malignant prior to the diagnostic FNA. The most common anatomic site for EMH was the liver, followed by the presacral soft tissue and pleura. While most EMH nodules were singular, a few presented with as many as three radiographically distinct nodules. The average EMH nodule measured 2.8 cm; the EMH liver nodules were larger and measured 4.3 cm on average (p = 0.0043). CONCLUSION: We share here the salient clinical and radiologic findings and the diagnostic cytopathologic features of EMH in an effort to familiarize the pathologist/cytotechnologist community with this fascinating albeit rare entity.

Sonographic findings in a fatal case of transient myeloproliferative disorder.

Transient myeloproliferative disorder is a unique disease in infants with Down syndrome that typically resolves spontaneously. In this report, we present a fatal case of transient myeloproliferative disorder with unusual sonographic findings including adrenal gland enlargement and thickening of the corpus callosum.

Transient myeloproliferative disorder in a newborn with Down syndrome.

This is the report of a newborn with Down syndrome diagnosed with transient myeloproliferative disorder (TMD) that required chemotherapy on the first day of life. Children with Down syndrome have a 10- to 20-fold increased risk of developing TMD. TMD is characterized by an uncontrolled proliferation of myeloblasts in the infant's peripheral blood and bone marrow. In most instances, this unique disorder has the ability to spontaneously "turn off" the overproliferation and enter a state of remission. Only supportive care is recommended for TMD during the first months of life unless the clinical condition requires intervention. As more cases of this baffling disorder are presented, it is important to share our experience to aid in management and diagnosis.

Prenatal sonographic findings and hematological abnormalities in fetuses with transient abnormal myelopoiesis with Down syndrome.

OBJECTIVES: To determine relevant prenatal findings of transient abnormal myelopoiesis (TAM) that have important prognostic implications. METHODS: The prenatal and postnatal medical records of all cases with confirmed TAM associated with Down syndrome were reviewed retrospectively, with emphasis on prenatal sonographic findings, fetal blood analysis, neonatal outcomes, and causes of death. RESULTS: From January 1992 to December 2005, seven cases were confirmed postnatally as having TAM associated with Down syndrome. Sonography demonstrated hydrops with hepatomegaly in four, and isolated hepatomegaly in two of these seven cases. There were no findings suggestive of cardiac failure in cases of hydrops. Fetal blood analysis revealed elevated liver enzyme levels in six cases and hypoalbuminemia in four cases. Comparison of sonographic findings with fetal blood findings demonstrated an association between hydrops and hypoalbuminemia. Four of the seven cases were fatal. All fatal cases were associated with hydrops and the main cause of death was coagulopathy due to liver failure, which may have resulted from infiltration of the liver by blast cells. CONCLUSIONS: Fetal TAM is associated with hepatomegaly and elevated liver enzyme levels. The prenatal finding with prognostic implications is hydrops, which may result from hypoalbuminemia due to liver failure.

Functional and morphological cardiac changes in myeloproliferative disorders (clinical study).

PURPOSE: Cardiac involvement is not well defined in myeloproliferative disorders (MPD). The purpose of this study was to evaluate the cardiac involvement by transthoracic echocardiography in MPD. MATERIALS AND METHODS: The study groups were 36 patients (mean age: 58+/-15 years, 20 female and 16 male) with MPD and 30 age-matched healthy controls. MPD group included 15 essential thrombocythemia (ET), eight chronic phase chronic myelogenous leukemia (CML), seven idiopathic myelofibrosis (MF) and six polcythemia vera patients. RESULTS: Valvular regurgitations were present in 14 patients (39%) and eight controls (27%), (P>0.05). Mitral regurgitation (MR) was more prominent in CML compared to controls (P=0.044). The rates of annular calcifications, valvular thickening, and vegetation like lesions were not different between MPD and control groups. Pulmonary hypertension (PHT) was present in six (17%) patients, but none of the controls (P=0.021). The rates of PHT in CML and MF were significantly higher than controls (P<0.05). The rate of PHT was not different in-between MPD patients with and without thromboembolic events, however, in MPD cases with thromboembolic events PHT was more common compared to controls (P=0.037). CONCLUSION: This study showed that valvular lesions were not more prevalent in MPD. PHT was the most prominent cardiac pathology in MPD (especially in CML, MF and thromboembolic events subgroups) compared to controls. Further evaluation of the cardiac changes in MPD subgroups with extended studies including trans-oesophageal echocardiography and longer follow-up periods would be appropriate.

Is the degree of fetal hepatosplenomegaly with transient abnormal myelopoiesis closely related to the postnatal severity of hematological abnormalities in Down syndrome?

We present three cases of transient abnormal myelopoiesis associated with trisomy 21 in which hepatomegaly was apparent during the fetal period. In the first case, the fetal hepatosplenomegaly was severe, multiple organ failure occurred in the neonatal period and death ensued at 4 weeks of age. In the second case, the hepatomegaly was moderate, and with conservative treatment in the neonatal period the outcome was good. In the third case, hepatomegaly was mild and improved spontaneously, and the hematological abnormalities required only conservative treatment in the neonatal period. Our experience raises the question of whether fetal hepatosplenomegaly is a predictor of transient myeloproliferative disorder with trisomy 21 and whether the degree of fetal hepatomegaly is a marker for the neonatal severity of hematological abnormalities.

Focal splenic lesions in myeloproliferative disease: association with fatal outcome.

BACKGROUND: A nodular tumor of the spleen in patients with myeloproliferative disease (MPD) is a very rare form of splenic involvement. The aim of the study was to describe the clinical data, sonographic patterns, and prognosis of nodular splenic infiltration in patients with MPD. MATERIALS AND METHODS: During a 20-year period, nodular splenic lesions were found in 10 out of 183 patients with MPD. Retrospectively, splenic size, echomorphology of the lesions, clinical data, sonographic follow-up, and survival were analyzed. RESULTS: In 9 out of 10 patients the lesions were hyperechoic--in one patient hypoechoic. In 3 patients the lesions were solitary. Seven patients had multiple nodular lesions. Low platelet count was seen in 8 patients; blast crisis was seen in 7 patients. The mean survival time was 2.9 months after detection of the splenic lesions. In one patient, autopsy confirmed the diagnosis of myelosarcoma of the spleen. CONCLUSION: The appearance of nodular splenic lesions in MPD is associated with blast crisis and a short survival. Definite histologic or cytologic findings associated with splenic nodules in MPD have not been identified yet. Myelosarcoma of the spleen is the most probable diagnosis suggested.