The mysterious pathways of cardiac myxomas: a review of histogenesis, pathogenesis and pathology

10× single-cell sequencing revealed cellular composition heterogeneity in cardiac myxoma with malignant glandular properties

Cardiac myxoma is the most common primary cardiac tumor in adults. The histogenesis and cellular composition of myxoma are still unclear. This study aims to reveal the role of myxoma cell components and their gene expression in tumor development. We obtained single living cells by enzymatic digestion of tissues from 4 cases of surgically resected cardiac myxoma. Of course, there was 1 case of glandular myxoma and 3 cases of nonglandular myxoma. Then, 10× single-cell sequencing was performed. We identified 12 types and 11 types of cell populations in glandular myxoma and nonglandular myxoma, respectively. Heterogeneous epithelial cells are the main components of glandular myxoma. The similarities and differences in T cells in both glandular and nonglandular myxoma were analyzed by KEGG and GO. The most important finding was that there was active communication between T cells and epithelial cells. These results clarify the possible tissue occurrence and heterogeneity of cardiac myxoma and provide a theoretical basis and guidance for clinical diagnosis and treatment.

Resolving the heterogeneous tumour microenvironment in cardiac myxoma through single-cell and spatial transcriptomics

BACKGROUND

Cardiac myxoma (CM) is the most common (58%-80%) type of primary cardiac tumours. Currently, there is a need to develop medical therapies, especially for patients not physically suitable for surgeries. However, the mechanisms that shape the tumour microenvironment (TME) in CM remain largely unknown, which impedes the development of targeted therapies. Here, we aimed to dissect the TME in CM at single-cell and spatial resolution.

METHODS

We performed single-cell transcriptomic sequencing and Visium CytAssist spatial transcriptomic (ST) assays on tumour samples from patients with CM. A comprehensive analysis was performed, including unsupervised clustering, RNA velocity, clonal substructure inference of tumour cells and cell-cell communication.

RESULTS

Unsupervised clustering of 34 759 cells identified 12 clusters, which were assigned to endothelial cells (ECs), mesenchymal stroma cells (MSCs), and tumour-infiltrating immune cells. Myxoma tumour cells were found to encompass two closely related phenotypic states, namely, EC-like tumour cells (ETCs) and MSC-like tumour cells (MTCs). According to RNA velocity, our findings suggest that ETCs may be directly differentiated from MTCs. The immune microenvironment of CM was found to contain multiple factors that promote immune suppression and evasion, underscoring the potential of using immunotherapies as a treatment option. Hyperactive signals sent primarily by tumour cells were identified, such as MDK, HGF, chemerin, and GDF15 signalling. Finally, the ST assay uncovered spatial features of the subclusters, proximal cell-cell communication, and clonal evolution of myxoma tumour cells.

CONCLUSIONS

Our study presents the first comprehensive characterisation of the TME in CM at both single-cell and spatial resolution. Our study provides novel insight into the differentiation of myxoma tumour cells and advance our understanding of the TME in CM. Given the rarity of cardiac tumours, our study provides invaluable datasets and promotes the development of medical therapies for CM.

Distinctive phenogroup to differentiate diagnosis of cardiac myxoma vs cardiovascular disease examining blood-based circulating cell biomarkers

Cardiac myxoma (CM) is a potentially life-threatening disease because frequently asymptomatic or debuts with aspecific manifestations. Definitive diagnosis is established by histopathological assessment including tumor and endothelial cell markers. To derive a specific panel of circulating cells antigenically detectable, pre-surgery peripheral blood samples of CM patients were analyzed. Pre-surgery peripheral blood samples from patients with CM were simultaneously analyzed for Circulating tumor cells (CTCs) and circulating endothelial cells (CECs) that were matched with tumor tissue profiles and with patient-derived xenografts (PDXs) distinguishing tumor regions. Moreover, CECs values in CM patients were further matched with CEC's levels in cardiovascular disease and control subjects. The blood-derived cytological specimens detected at least 1-3 CTCs/ml in 10 tested CM samples (p = 0.0001) showing specific CM features preserved in the central zones of the tumor. The central zone of the primary tumor, supported by a vessel density rate (55 ± 7%), with a proliferative profile of 32 ± 3% and a percentage of Calretininpos cells (p = 0.03), is the principal site of CTCs (r = 00) dissemination. The subsets of endothelial cells recognized in the blood were indifferent to their topological distribution within the tumor and corresponding PDXs. With further refinement and validation in large cohorts, multiparametric liquid biopsies can optimally integrate clinically informative datasets and maximize their utility in pre-surgery evaluation of CM patients. Blood-derived culture's protocol provides a versatile method capable of viable analysis of CTCs of non-hematological rare tumors which conventional antibody-mediated analytical platform is unable to perform. Distinctive blood- based cell phenotype contributes to differentiate CM from other differentials assuring its prompt surgical resection by combining blood-based cell biomarkers integrated with clinically informative datasets.

Pathological features of primary cardiac myxoid tumour in dogs: a review of 11 cases (2002-2022)

This report documents the pathological features of primary cardiac myxoid tumour (MT) in 11 dogs. Macroscopically, all the tumours were located in the tricuspid valve (TV), its septal leaflet being predominantly affected. Therefore, it appears that the TV is the most common site of occurrence for cardiac MT in dogs. Two gross anatomical types of canine valvular MT were evident. Seven of the 11 tumours were round or oval with a smooth or gently lobulated and glistening surface, while the other four were gelatinous, multilobulated and polypoid, with an irregular surface. Microscopically, in nine cases the tumours had an abundant myxoid matrix within which elongated spindle-shaped cells with no remarkable cytological atypia were sparsely embedded, suggesting a benign character (ie, myxoma). In the other two cases the tumours consisted of variably dense, haphazardly arranged, interlacing streams of anaplastic spindle-shaped or polygonal cells containing many mitotic figures, indicative of a malignant form of myxoma (ie, myxosarcoma). Isolated or clustered collections of myxoma cells (eg, cords, rings, syncytia) characteristic of human atrial myxoma were only rarely evident or lacking in all 11 cases, indicating that rarity or absence of such structural features may be specific to valvular MTs. Immunohistochemical findings were indicative of smooth muscle differentiation of the neoplastic cells. Tumour embolization to the intrapulmonary arteries and/or tumour implantation on the endocardium of the right heart chambers was evident only in the four cases of irregular-surfaced MT.

Management of calcified right atrial myxoma extending into the inferior vena cava: a case report

Cardiac myxomas can rarely involve the right atrium, get calcified and involve the inferior vena cava (IVC). Early surgical intervention is critical to prevent life-threatening complications. We presented the case of a 39-year-old male with fever, cough and shortness of breath for 1 week. Initial laboratory investigations revealed leucocytosis and thrombocytopenia. His electrocardiogram was normal, and his chest X-ray showed bilateral infiltrates. Based on the findings of a high-resolution chest computed tomography scan, echocardiography and cardiac magnetic resonance imaging, we made a provisional diagnosis of calcified right atrial myxoma extending up to the IVC. We managed the case with cardiopulmonary bypass via aortic cannulation followed by a right atriotomy. Post-operatively, the patient's condition improved and was doing well on monthly follow-ups.

Case report: Left atrial myxoma with morphology of cavernous hemangioma supplied by the right coronary artery

Here, we report an unusual case of left atrial myxoma presented with morphology of cavernous hemangioma supplied by the right coronary artery. Surgical resection of the left atrium myxoma was performed, and the patient experienced an uneventful recovery during hospitalization.

Somatic Mutation of PRKAR1A in Four Cases of Sporadic Cardiac Myxoma

BACKGROUND

Inactivating mutations of the protein kinase A regulatory subunit 1 alpha (PRKAR1A) gene have been reported in familial cardiac myxoma. However, the role of PRKAR1A mutation in sporadic cardiac myxoma remains unknown.

METHODS

Targeted next-generation sequencing (NGS) was performed to identify mutations with the PRKAR1A gene in seven cases of sporadic cardiac myxomas. Sanger sequencing of DNA from cardiac myxoma specimens and matched peripheral blood samples was performed to verify the identified mutations.

RESULTS

Targeted NGS of myxoma DNA revealed 232 single nucleotide variants in 141 genes and 38 insertion-deletion mutations in 13 genes. Six PRKAR1A mutations were identified in four of the seven cardiac myxoma cases, and thus, the PRKAR1A inactivating mutation rate was 57.2% (4/7, 95% CI=0.44-0.58, P<0.05). The PRKAR1A variants identified by Sanger sequencing analysis were consistent with those from the NGS analysis for the four myxoma specimens. All of the pathogenic PRKAR1A mutations led to premature termination of PRKAR1A, except for one synonymous mutation. Moreover, none of the nonsense and missense mutations found in the myxoma specimens were found in the matched peripheral blood samples.

CONCLUSION

Pathogenic mutations of the PRKAR1A gene were identified in tumor specimens from four cases of sporadic cardiac myxoma, and the absence of these mutations in peripheral blood samples demonstrated that they were somatic mutations.

Gender-Related Outcomes after Surgical Resection and Level of Satisfaction in Patients with Left Atrial Tumors

BACKGROUND

Cardiac tumors are rare, with a low incidence of between 0.0017 and 0.19%. The majority of cardiac tumors are benign and predominantly occur in females. The aim of our study was to examine how outcomes differ between men and women.

METHODS

From 2015 to 2022, 80 patients diagnosed with suspected myxoma were operated on. In all patients, preoperative, perioperative, and postoperative data were recorded. Such patients were identified and included in a retrospective analysis focused on gender-related differences.

RESULTS

Patients were predominantly female (n = 64; 80%). The mean age was 62.76 ± 13.42 years in female patients and 59.65 ± 15.84 years in male patients (p = 0.438). The body mass index (BMI) was comparable in both groups: between 27.36 ± 6.16 in male and 27.09 ± 5.75 (p = 0.945) in female patients. Logistic EuroSCORE (LogES) (female: 5.89 ± 4.6; male: 3.95 ± 3.06; p = 0.017) and EuroSCORE II (ES II) (female: 2.07 ± 2.1; male: 0.94 ± 0.45; p = 0.043), both scores to predict the mortality in cardiac surgery, were significantly higher in female patients. Two patients died early, within 30 days after surgery: one male and one female patient. Late mortality was defined as the 5-year survival rate, which was 94.8%, and 15-year survival rate, which was 85.3% in our cohort. Causes of death were not related to the primary tumor operation. The follow up showed that satisfaction with surgery and long-term outcome was high.

CONCLUSION

Predominately female patients presented with left atrial tumors over a 17-year period. Relevant gender differences aside from that were not evident. Surgery could be performed with excellent early (within 30 days after surgery) and late results (follow up after discharge).

Cardiac myxoma with atypical cell population mimicking malignancy - a diagnostic pitfall

Herein, a case of a 45-year-old woman is reported with left atrial myxoma showing unique histological findings mimicking malignancy. For 3 months before surgery, the patient suffered from a long-standing fever of unknown etiology, malaise and weight loss; she had no history of malignancy. The CT scan revealed a tumorous mass in the left atrium. Grossly, the tumor had a smooth rounded surface with areas of haemorrhage on the cut surface. Microscopic examination revealed two distinct regions. One showed classical myxoma histology, the other atypical and highly cellular population with sarcoma-like or melanoma-like features mixed with inflammatory cells and posthemorrhagic changes. Immunohistochemically, the atypical cells expressed calretinin and CD31, analogous to the neighbouring bland myxoma cells. Negative markers included SOX10, S100, Melan A, HMB45, CD34, desmin, ERG, CK, LCA, CD68 and MDM2; SMARCB1/INI1 was retained. The proliferation index Ki67 was low, in about 1 % of atypical cells. The results suggest exaggerated reactive and degenerative changes of the myxoma cells rather than true malignant transformation. Similar case reports of cardiac myxomas and diagnostic challenges are discussed.

Morphological characteristics of cardiac myxoma causing embolism: a series of 40 years of experience at a single institute

Systemic and cerebral embolisms are serious complications of associated with cardiac myxoma. Embolism risk reportedly depends on the gross and histological morphology. This study is aimed at analyzing the morphologic pattern of excised cardiac myxoma as a high-risk embolic cause. Between 1978 and April 2022, 116 surgical specimens of cardiac myxomas were recorded at the pathology department of our hospital. The tumors were classified into three types based on their macroscopic shapes and external morphology-round-smooth, irregular, and villous-to investigate the embolic complications. Of the 116 specimens, 106 macroscopic images of cardiac myxoma (89% were located in the left atrium) were prepared. Round-smooth types were found in 36 (34.0%) patients, irregular types in 32 (30.2%) patients, and the villous types in 38 (35.8%) patients. Multivariable analysis revealed that a villous external appearance was an independent predictor of embolic events (odds ratio: 8.7; 95% confidence interval: 2.4-42.1; p < 0.001). Villous external appearance of cardiac myxoma was associated with the highest risk of distal embolism.

Resection of Orbital Myxoma With Magnetic Resonance Imaging Evidence of Ethmoid Sinus Origin: Case Report and Review of 20 Patients in the Literature

A 41-year-old woman showed a palpable mass at the superonasal orbital edge on the right side. Magnetic resonance imaging demonstrated a lobulated fluid-containing tubular mass which extended anteriorly to posteriorly along the medial orbital wall, nasal to the eyeball. She was followed once a year for 8 years until the age of 49 years when she decided to undergo surgical resection because of the enlarged mass. The lobulated large mass was resected and the pathology showed sparsely distributed spindle cells, positive for CD34, in alcian blue-positive mucous substances, indicative of myxoma. Postoperative magnetic resonance imaging showed residual lobulated tubular mass along the optic nerve on the medial side and superior to the eyeball. The residual orbital mass showed stable structure with more evident connection with the ethmoid sinus lesion, suggestive of the ethmoid origin, in 12 years until the age of 61 years. In the review of 20 patients with orbital myxomas in the literature, in addition to this case, roughly classified locations in the orbit were retrobulbar in 8 patients, on the lateral side of the orbit in 4, on the superior side in 6, on the medial side in 1 (this patient), and in the orbit with no specific description in 2. In pathological examinations, immunohistochemistry was not done in 8 patients, done but all negative in 2, and positive in 11 patients: nerve sheath myxoma was diagnosed in 3 patients based on positive S100 staining. Orbital myxoma is rare but considered in differential diagnosis of orbital masses.

Cardiac myxomas: A narrative review

Cardiac myxomas are common primary neoplasms of the heart. They are biologically benign but “functionally malignant” because of the potential for embolization. They arise most commonly from the left atrium, but no chambers of the heart are immune. They may be sporadic in the majority but also familial as a part of the Carney complex. Two morphological forms exist: polypoid and papillary. Polypoid myxomas often present with obstructive features, while the papillary forms are more prone to embolization. Histogenesis is still controversial; the current view centres around origin from the primitive pluripotent mesenchymal cells. They may be of giant proportion, be calcified or get infected. Clinical presentation typically involves the triad of intracardiac obstruction, embolic events and constitutional symptoms. Precordial examination findings may simulate those of mitral or tricuspid stenosis. The presence of tumour plop and change of the physical findings with changing position may help differentiation between the two. Echocardiography is the investigation of choice. Echogenic polypoid or papillary mobile mass within the atrial cavity remaining attached to the interatrial septum through a stalk are the tell-tale echocardiographic features. Cardiac magnetic resonance and computed tomographic scanning may have incremental diagnostic value. Histopathological examination reveals abundant loose myxoid stroma with scattered round, polygonal or stellate cells with dense irregular nuclei. Genetic testing may detect mutations in the PRKAR1A gene in the familial form of cardiac myxoma, i.e. the Carney complex. Surgical excision is the mainstay of treatment with low operative mortality, excellent postoperative survival and low recurrence rate. The current trend favours minimal-access surgery with or without robotic assistance. Physicians should have appropriate preparedness to make a timely diagnosis and enthusiastic treatment to avoid potentially fatal complications.

Right atrial myxoma as the first manifestation of granulomatosis with polyangiitis, and a possible association with vascular endothelial growth factor (VEGF) and interleukin 6 (IL-6): a case report and review of the literature

Background

Granulomatosis with polyangiitis and myxomas are rare conditions previously described to co-exist. Cardiac masses are often presumed to be myxomas rather than lesions of granulomatosis with polyangiitis.

Case presentation

We present a review of the symptoms for the two diagnoses along with the first verified case.

Conclusions

Two possible risk factors for developing myxomas (VEGF and IL-6) are explored and discussed.

Gαs-Protein Kinase A (PKA) Pathway Signalopathies: The Emerging Genetic Landscape and Therapeutic Potential of Human Diseases Driven by Aberrant Gαs-PKA Signaling

Many of the fundamental concepts of signal transduction and kinase activity are attributed to the discovery and crystallization of cAMP-dependent protein kinase, or protein kinase A. PKA is one of the best-studied kinases in human biology, with emphasis in biochemistry and biophysics, all the way to metabolism, hormone action, and gene expression regulation. It is surprising, however, that our understanding of PKA's role in disease is largely underappreciated. Although genetic mutations in the PKA holoenzyme are known to cause diseases such as Carney complex, Cushing syndrome, and acrodysostosis, the story largely stops there. With the recent explosion of genomic medicine, we can finally appreciate the broader role of the Gαs-PKA pathway in disease, with contributions from aberrant functioning G proteins and G protein-coupled receptors, as well as multiple alterations in other pathway components and negative regulators. Together, these represent a broad family of diseases we term the Gαs-PKA pathway signalopathies. The Gαs-PKA pathway signalopathies encompass diseases caused by germline, postzygotic, and somatic mutations in the Gαs-PKA pathway, with largely endocrine and neoplastic phenotypes. Here, we present a signaling-centric review of Gαs-PKA-driven pathophysiology and integrate computational and structural analysis to identify mutational themes commonly exploited by the Gαs-PKA pathway signalopathies. Major mutational themes include hotspot activating mutations in Gαs, encoded by GNAS, and mutations that destabilize the PKA holoenzyme. With this review, we hope to incite further study and ultimately the development of new therapeutic strategies in the treatment of a wide range of human diseases. SIGNIFICANCE STATEMENT: Little recognition is given to the causative role of Gαs-PKA pathway dysregulation in disease, with effects ranging from infectious disease, endocrine syndromes, and many cancers, yet these disparate diseases can all be understood by common genetic themes and biochemical signaling connections. By highlighting these common pathogenic mechanisms and bridging multiple disciplines, important progress can be made toward therapeutic advances in treating Gαs-PKA pathway-driven disease.

Autophagy in cardiac myxoma: An important puzzle piece in understanding its inflammatory environment

BACKGROUND

Cardiac myxomas are rare, predominantly sporadic tumors that can cause heart failure and systematic inflammatory symptoms, and increase the risk of emboli. Their pathophysiology remains poorly understood, but intra-tumoral inflammation and senescence seem to be implicated in it. One of the principal cellular mechanisms implicated in tumor progression is autophagy, largely unknown in myxomas. Thus, our study aimed to investigate the presence of autophagic markers in myxomas and to correlate it with their immune microenvironment.

METHODS

Twenty-five cardiac myxomas were studied for the autophagic markers LC3B and p62/sequestosome 1 and were compared with markers of the immune microenvironment.

RESULTS

Most myxomas showed expression of both autophagic markers. We found a positive correlation between LC3B and PD-L1, as well as CD163, and a negative correlation between LC3B and CD8, CD20, CD138, and CD117 infiltration.

CONCLUSION

Our data not only confirm the presence of autophagic markers within cardiac myxomas but also suggest a possible association with their immune microenvironment.

Cardiac Melanoma Metastasis with ERBB2 Gene Amplification: A Potential for Future Targeted Therapy

Cardiac tumors are rare, and their treatment differs interindividually regarding the histopathological proprieties and the stage of disease. Authors present a case of symptomatic cardiac melanoma metastasis that expressed an ERBB2 (HER2) gene amplification in a course of the disease that has not yet been reported. The frail patient with a history of pulmonary and renal carcinoma, was admitted to the hospital due to a symptomatic left atrial tumor mass. The patient underwent a tumor-resecting cardiac surgery. At first mistaken for myxoma on echocardiography, the histopathological examination of the tumor revealed a melanoma of acral or mucosal origin. The melanoma metastasis was negative for common genetic mutations in BRAF, NRAS or KIT genes, and for the presence of NTRK genes fusions, but carried ERBB2 (HER2) gene amplification. The absence of standard gene mutations rendered it unresponsive to treatment with BRAF and MEK inhibitors. This molecular finding is rare in melanomas and represented a therapeutic target for off-label systemic treatment with drugs, primarily aimed at ERBB2 positive breast, gastric, and gastroesophageal junction cancers. A rare finding like this justifies molecular genetic analysis of unusual tumor specimen and guarantees optimal treatment for uncommon types of cardiac metastatic tumors.

Senescence, immune microenvironment, and vascularization in cardiac myxomas

AIMS

Cardiac myxomas are rare tumors of incompletely elucidated pathogenesis. The aim of this study is to explore the possible presence of a senescence phenotype in cardiac myxomas, associated with an inflammatory and vasculogenic tumor microenvironment.

METHODS AND RESULTS

This is a retrospective study of 29 cardiac myxomas with immunohistochemical detection of various inflammatory, vascular, and senescence markers. We show that all myxomas contain tumor cells in senescence overexpressing p16, and a fraction of senescent endothelial cells. Macrophages are the principal inflammatory cell population, followed by cytotoxic T cells, with fewer plasma cells, mastocytes, and B lymphocytes. These populations are found in different intratumoral localizations. Larger tumor volume is associated with a lower percentage of myxoid matrix, higher cellularity, higher macrophage, and lower number of mast cells as well as higher PD-L1 expression by inflammatory cells. Higher vascular density is associated with higher percentage of B cells, a lower number of macrophages and higher number of mastocytes, and lower PD-L1 expression by inflammatory cells. Tumors with higher vascular density and higher cellularity show higher amounts of p16 senescent endothelial cells.

CONCLUSIONS

Myxoma tumor cells are in senescence and reside inside a tumor microenvironment with a distinct inflammatory profile rich in macrophages and cytotoxic T cells, and a rich vasculature, probably attributed to a senescence-associated secretory phenotype.

Recurrent cardiac intimal sarcoma misdiagnosed as a myxoma or malignant transformation of a cardiac myxoma?

Cardiac intimal sarcoma is extremely rare and aggressive primary malignant cardiac tumors. Here, we reported the case of a young man initially operated for a tumor of the left atrium, causing a dynamic obstruction of the mitral valve and (mis-)diagnosed as a myxoma at the histopathological analysis. Patient presented a local recurrence at 3 months and was reoperated. Pathology revealed this time the presence of an intimal sarcoma. Patient received adjuvant chemotherapy. Despite a good local control, the 1-year follow-up positron emission tomography scan revealed the presence of a metastasis in the left adrenal gland that was surgically resected. This article aims to highlight the risk of misdiagnosis in case of cardiac tumors, the hypothetical concept of malignant transformation of a cardiac myxoma, the aggressive course of the extremely rare cardiac intimal sarcoma, and the therapeutic modalities available to treat this pathology.

Cardiac Myxoma: Review and Update of Contemporary Immunohistochemical Markers and Molecular Pathology

Cardiac myxoma is an uncommon benign mesenchymal neoplasm of the heart. It usually arises in the left atrium, near the valve of the fossa ovalis, and most frequently affects adults in the third through the sixth decades of life. It is hypothesized to arise from subendothelial vasoformative reserve cells or primitive cells that differentiate along the lines of the endothelium, but this remains speculative. Microscopically, the neoplastic cells are arranged individually, and nests, and are oriented in single or multiple layers around vascular channels. The neoplastic cells are immunoreactive for vimentin, calretinin, S100, nonspecific enolase, factor VIII, CD31, and CD34. The tumor can have diverse clinical presentations depending on its location and extent of disease and is predisposed to embolization. The current treatment is prompt surgical excision.

Mycosis fungoides and gastric T-cell lymphoma: A case report

Mycosis fungoides (MF) is a cutaneous malignant lymphoma with an extended clinical course. MF presents in series of dermatological manifestations, beginning with patches and plaques of the skin, and eventually evolving into tumours. Often MF can occur for extended periods without worsening of external symptoms, while the disease advances internally in organs such as lymph nodes, liver, spleen, lung, bone marrow, gastrointestinal tract, pancreas and kidney. The present report presents a clinical case in which gastrointestinal symptomatology occurred a decade after the first dermatological manifestation. Immunohistochemical analysis of the skin, along with small bowel biopsies revealed evidence of gastric T-cell lymphoma. To the best of our knowledge, the present study is the first to describe such a case in the literature.

Innate and Adaptive Immunity Linked to Recognition of Antigens Shared by Neural Crest-Derived Tumors

In the adult, many embryologic processes can be co-opted by during cancer progression. The mechanisms of divisions, migration, and the ability to escape immunity recognition linked to specific embryo antigens are also expressed by malignant cells. In particular, cells derived from neural crests (NC) contribute to the development of multiple cell types including melanocytes, craniofacial cartilage, glia, neurons, peripheral and enteric nervous systems, and the adrenal medulla. This plastic performance is due to an accurate program of gene expression orchestrated with cellular/extracellular signals finalized to regulate long-distance migration, proliferation, differentiation, apoptosis, and survival. During neurulation, prior to initiating their migration, NC cells must undergo an epithelial–mesenchymal transition (EMT) in which they alter their actin cytoskeleton, lose their cell–cell junctions, apicobasal polarity, and acquire a motile phenotype. Similarly, during the development of the tumors derived from neural crests, comprising a heterogeneous group of neoplasms (Neural crest-derived tumors (NCDTs)), a group of genes responsible for the EMT pathway is activated. Here, retracing the molecular pathways performed by pluripotent cells at the boundary between neural and non-neural ectoderm in relation to the natural history of NCDT, points of contact or interposition are highlighted to better explain the intricate interplay between cancer cells and the innate and adaptive immune response.

Metastatic lesions of atrial myxoma. A pathologist can clinch them all

Atrial myxomas are the most common primary benign cardiac tumors. The embolization of tumor particles is not infrequent, and in nearly half of them, the cerebral arteries are affected, usually leading to embolic ischemic stroke. Formation of intracranial aneurysms, development of parenchymal brain metastasis, and intracerebral hemorrhage due to ruptured aneurysms are rarer. Diagnosis of such lesions in a previously undiagnosed case of myxoma may be challenging for a pathologist. Herein, we present two patients of cardiac myxoma with varied neurological manifestations and their pathological findings.

Innate Immunity: A Common Denominator between Neurodegenerative and Neuropsychiatric Diseases

The intricate relationships between innate immunity and brain diseases raise increased interest across the wide spectrum of neurodegenerative and neuropsychiatric disorders. Barriers, such as the blood–brain barrier, and innate immunity cells such as microglia, astrocytes, macrophages, and mast cells are involved in triggering disease events in these groups, through the action of many different cytokines. Chronic inflammation can lead to dysfunctions in large-scale brain networks. Neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and frontotemporal dementia, are associated with a substrate of dysregulated immune responses that impair the central nervous system balance. Recent evidence suggests that similar phenomena are involved in psychiatric diseases, such as depression, schizophrenia, autism spectrum disorders, and post-traumatic stress disorder. The present review summarizes and discusses the main evidence linking the innate immunological response in neurodegenerative and psychiatric diseases, thus providing insights into how the responses of innate immunity represent a common denominator between diseases belonging to the neurological and psychiatric sphere. Improved knowledge of such immunological aspects could provide the framework for the future development of new diagnostic and therapeutic approaches.

Cardiac myxoma and neural crests: a tense relationship

In cardiac myxomas, the malignant transformation process, selecting incidental gene mutations and leading to loss of proliferation control, has not a so drastic effects in terms of growth rate of tumor mass, but frequently the particular location of lesion engrosses the high risk for health. For accurate cancer cell profiling, it is important to establish the embryologic origin of malignant cells and their initial commitments, above all, in the sight of therapeutic strategies and solutions. Here, we advance, for cardiac myxoma, the hypothesis of an origin from cardiac neural crest cells and we attempt to support it by an integrated discussion of current knowledge about embryological characteristics of neural crest cells and most recent studies focusing cardiac myxomas. We discuss the relationship between the basic plasticity of cardiac neural crest cells and some typical mutations arising in neoplastic lesions as well as the expression of typical cell markers of neural crests derivatives. Dysfunctions in proliferative and migratory programs, focused in other studies, are evaluated in the context of the topological and histopathological characteristics of cardiac myxomas.

An atrial septal aneurysm with an organized thrombus in an asymptomatic patient: A case report

INTRODUCTION

An atrial septal aneurysm (ASA) is a rare congenital cardiac deformity characterized by interatrial septum protruding into atria forming a saccular structure.

PATIENT CONCERNS

In our case, a 42-year-old female patient presented to our hospital complained of palpitation.

DIAGNOSIS

Transthoracic echocardiography detected a 3.4 × 3.4 cm circular mass attached to the interatrial septum in right atrium complicated with a 6 mm secundum atrial septal defects (ASD).

INTERVENTIONS

The patient received a cardiopulmonary bypass surgery to remove the mass and close the ASD.

OUTCOMES

The mass turned out to be an organized thrombus with calcium deposition and fibrinoid necrosis.

CONCLUSION

ASA is a potential location of atrial thrombus because of the stagnation of blood. Systemic embolism events are the main complications of ASA. Surgery or anticoagulation is both recommended in patients with ASA with thrombus.

Does a polarization state exist for mast cells in cancer?

The data of literature are discordant about the role of mast cells in different types of neoplasms. In this paper the authors propose the hypothesis that tumor-associated mast cells may switch to different polarization states, conditioning the immunogenic capacities of the different neoplasms. Anti-inflammatory polarized mast cells should express cytokines such as interleukin-10 (IL-10) and then mast cells number should be inversely related to the intensity of inflammatory infiltrate. On the contrary, when mast cells do not express anti-inflammatory cytokines their number should be directly related to the intensity of the inflammatory infiltrate. In this paper we briefly argue around feasible approaches, based on the retrospective studies of tumor tissue samples from neoplasms considered "immunologically hot" and neoplasms considered "immunologically cold", through immunohistochemistry and immunofluorescence techniques (confocal microscopy). The establishment of the actual existence of a polarization interchange of mast cells, could lead to a new vision in prognostic terms, useful to contrive new approaches in immunotherapy of tumors.

Hemodynamic management of a patient with a huge right atrium myxoma during thoracic vertebral surgery: A case report

RATIONALE

Myxoma is the most common primary benign cardiac tumor, which could lead to some fatal complications because of its strategic position.

PATIENT CONCERNS

The patient was admitted to our hospital due to sudden onset of palpitation, chest tightness, mild fever, night sweats, accompanied with bilateral lower extremities adynamia, and paralysis for 5 days, but no obvious syncope and edema.

DIAGNOSES

Transthoracic echocardiography showed a giant mobile myxoma (72 × 58 mm) in the right atrium (RA). Magnetic resonance imaging revealed an erosive space-occupying lesion located between the first and third thoracic vertebrae.

INTERVENTIONS

Thoracic vertebral lesions were resected immediately to rescue the incomplete paraplegia. After the patient was placed in the prone position, significant hemodynamics changes were observed due to the displacement of the huge RA myxoma.

OUTCOMES

Stable hemodynamics was maintained during the operation through control of fluid infusion combined with vasoactive drugs.

LESSONS

Change in body position may lead to obstruction of intracardiac blood flow in patients with giant myxoma. This clinical manifestation is rarely reported.

[On the histogenesis of cardiac myxoma]

OBJECTIVE

to investigate the morphological and phenotypic features of cardiac myxoma (CM), to discuss argumentative issues on the sources of its growth.

SUBJECTS AND METHODS

The investigation included 176 sporadic and familial myxomas originating from different cardiac chambers (96% from the atria). The histological, ultrastructural, and immunohistochemical features of the cells and vessels of this tumor were studied.

RESULTS

The morphological and phenotypic features of the embryonic endothelium resembling the cells of the primary cardiovascular network were found in the cells and vessels of CM. No signs of other mesenchymal derivatives were detected.

DISCUSSION

The authors anticipate that there is focal cessation of maturation of the embryonic endocardial endothelium and its persistence - hamartia. Postnatal proliferation of embryonic hamartia forms the tumor hamartoma. Differentiated cells may retain the phenotypic (but not morphological) features of closely related cells that have a common precursor.

CONCLUSION

The results of the study have allowed the authors to consider CM to be hamartoma, a monohistioid benign embryonic endocardial endothelioma. Our findings do not exclude the possibility of developing CM from pluripotent mesenchymal cells.

Acute heart failure related to a large left atrial myxoma

An association between atrial myxoma and left ventricular failure is rarely described, is not completely understood, and may have multiple etiologies. We present a 49-year-old man with no history of cardiovascular disease who was admitted to our hospital with pulmonary edema. He was in atrial fibrillation with rapid ventricular response. Echocardiography showed a 10.5-cm left atrial myxoma, which had been asymptomatic until the onset of congestive heart failure in the presence of severe left ventricular systolic dysfunction. Left ventricular inflow obstruction associated with the giant atrial mass could not be the only cause for acute heart failure.

A patient with an unusual cyst of the inter-atrial septum and atrial sepal defect

Hepatic and renal cysts are relatively common among healthy people, but there are few published reports of primary cysts of the atrial septum. Here, we report a case of an unusual cyst of the atrial septum accompanied by atrial septal defect (ASD) in a 42-year-old woman. Microscopic examination showed the deposition of calcium salts within the tissue mass and an organized thrombus surrounded by a fibrous capsule. The case was discussed with reference to the relevant published literature and compared to other documented types of atrial septal cysts. The final diagnostic conclusion was a primary atrial septal cyst.

A case report of an angiomyxoma in the liver

Angiomyxomas are uncommon myxoid tumours arising most commonly from the pelvis. A 46-year-old woman with a history of polycystic kidney disease presented asymptomatically for surveillance ultrasonography; changes were noted in the size and morphology of her liver cysts. Subsequent radiological assessment displayed features suspicious of malignancy and a right hemihepatectomy was performed with curative intent. Pathological examination of the resected specimen found histology consistent with an angiomyxoma arising primarily from the liver parenchyma. Follow-up review of the patient has been uneventful with annual imaging showing no evidence of recurrence. Angiomyxomas do not characteristically invade other tissues. However, any liver lesion displaying suspicious features of malignancy should be resected in the absence of disseminated disease.

Innate immunity in cardiac myxomas and its pathological and clinical correlations

Cardiac myxomas are the most common benign cardiac tumor. We investigated the immunohistochemical properties of 11 surgically excised cardiac myxomas, in order to analyze the correlation between macrophages and mast cell populations and clinical parameters. CD68⁺/CD163⁻/iNOS⁻ (M0) cells represent the most abundant macrophage phenotype; however, CD68⁺/CD163⁺ cells (M2) were also frequent. CD68⁺/iNOS⁺ (M1) elements were rare. Mast cells, defined as a population of c-kit (CD117)⁺ and/or tryptase⁺ cells were also detected. Statistical analysis showed significant correlations between c-kit (CD117)⁺ and tryptase, CD68 and erythrocyte sedimentation rate (ESR), ESR and red blood cell count (RBC), and prothrombin time and platelet count. The inverse correlation between RBCs in peripheral blood and ESR suggested that anemia associated with chronic inflammatory disease is a noncasual event in patients suffering from cardiac myxoma. Mechanical hemolysis may be only a minor component of anemia, according to the lack of correlation between echographic surface and RBCs. Moreover, tumor size did not correlate with ESR, showing that inflammatory state may depend from both tumor cells population and inflammatory infiltrate. In the future, modulation of macrophage polarization in cardiac myxomas might represent important therapeutic target.

An optimized procedure for on-tissue localized protein digestion and quantification using hydrogel discs and isobaric mass tags: analysis of cardiac myxoma

An optimized workflow for multiplexed and spatially localized on-tissue quantitative protein analysis is here presented. The method is based on the use of an enzyme delivery platform, a polymeric hydrogel disc, allowing for a localized digestion directly onto the tissue surface coupled with an isobaric mass tag strategy for peptide labeling and relative quantification. The digestion occurs within such hydrogels, followed by peptide solvent extraction and identification by liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-MS/MS). Since this is a histology-directed on-tissue analysis, multiple hydrogels were placed onto morphologically and spatially different regions of interest (ROIs) within the tissue surface, e.g., cardiac myxoma tumor vascularized region and the adjacent hypocellular area. After a microwave digestion step (2 min), enzymatically cleaved peptides were labeled using TMT reagents with isobaric mass tags, enabling analysis of multiple samples per experiment. Thus, N = 8 hydrogel-digested samples from cardiac myxoma serial tissue sections (N = 4 from the vascularized ROIs and N = 4 from the adjacent hypocellular areas) were processed and then combined before a single LC-MS/MS analysis. Regulated proteins from both cardiac myxoma regions were assayed in a single experiment. Graphical abstract The workflow for histology-guided on-tissue localized protein digestion followed by isobaric mass tagging and LC-MS/MS analysis for proteins quantification is here summarized.

Association between herpes simplex virus Types 1 and 2 with cardiac myxoma

Most cases of atrial myxoma are sporadic, and the exact etiology is unknown. We examined if herpes simplex virus (HSV)-1 and HSV-2 antigens and/or DNA could be detected in a cohort of Iranian patients with cardiac myxomas. From July 2004 to June 2014, among a total of 36,703 patients undergoing open heart surgeries, consecutive patients with cardiac myxoma who were treated by surgical excision at our center included in this study. Of 73 patients studied, 56% were female with a mean age of 54 years (ranging from 23 to 77 years). Seventy-four myxomas were surgically removed from 73 patients, since one patient had two myxomas which were located on both the right atrium and right ventricle. The materials for this analysis were retrospectively gathered from extracted tumors that stored in a pathology bank of tissue paraffin blocks. The formalin fixed paraffin embedded tissue samples were investigated for HSV genomic DNA by both immunohistochemistry (IHC) and polymerase chain reaction (PCR) analysis. In all 74 cases there was no presence of HSV 1 and HSV 2 infection. This suggests that HSV may not play a role in sporadic cardiac myxomas; however, evidence for such association is currently lacking, and further studies are required to determine such a role.

Left ventricular cardiac myxoma and sudden death in a dog

Background

Myxoma is a very rare benign cardiac tumor in dogs. This is the first description of a cardiac myxoma originating from the left ventricular outflow tract, presumably causing sudden death.

Case presentation

A previously healthy 12-year-old male West Highland white terrier was found dead during its 1-week stay in a kennel. The dog was known to have a cardiac murmur. On necropsy, a pedunculated neoplasia was found attached to the interventricular aspect of the left ventricular outflow tract, resulting in almost complete obstruction of the aorta. As this was the only abnormality identified, the tumor was considered as the cause of sudden death. Histopathologic findings were compatible with a myxoma.

Conclusions

Benign intraluminal tumors of the heart are very rare in dogs, but may have fatal consequences. Echocardiography could have revealed the cause of the cardiac murmur of this previously asymptomatic dog. Surgical removal could have been possible, as the tumor was pedunculated.

[About a case of a recurrent glandular cardiac myxoma in a child]

Primary cardiac tumors are extremely rare and mainly benign. The majority of these are myxomas (40%). Myxoma are generally sporadic tumors which occur most commonly in adult females between 30 and 40 years, and are seldom found in the paediatric population (5%). Seven percent are associated with igenetic diseases. We report the case of an eight-year-old boy presenting a recurrent glandular cardiac myxoma. In 2011, he presented a deterioration of the general state. An echocardiography highlighted a left atrial mass on the interatrial septum, with a pedicular insertion. On the microscope, it consisted of a proliferation of stellate cells isolated or clustered in rudimentary vessels in a myxoid stroma presenting haemorrhage changes. These cells expressed CD34 and calretinine. Glandular elements without atypia were clustered within the myxomatous proliferation. They expressed cytokeratin (CK) 7. Surgical resection was macroscopically complete. In 2014, the boy had a sudden neurological deficit during a football match. An echocardiography revealed a recurrence at the same location. The lesion was excised and addressed in several fragments. Classical myxoma was associated with glands without atypia. This last component expressed CKAE1/AE3 and CK7. Ki67 index of proliferation was low. The surgical reintervention was macroscopically complete. The final diagnosis was glandular cardiac myxoma. A genetic survey was conducted, showing the presence of Carney complex. This is the first description in the litterature of a recurrent glandular cardiac myxoma occuring in a child.

Astrocyte elevated gene-1 regulates CCL3/CCR5-induced epithelial-to-mesenchymal transition via Erk1/2 and Akt signaling in cardiac myxoma

In recent years, astrocyte elevated gene-1 (AEG-1) has been reported as a key mediator that is involved in the epithelial-to-mesenchymal transition (EMT) process. However, the mechanisms underlying CCL3/CCR5-AEG-1 pathway-mediated EMT in cardiac myxoma (CM) has not been well featured till now. We used immnohistochemistry and immunoblotting to assess the expression of CCR5 and AEG-1 in 30 cases of CM tissues and cells. Subsequently, cultured CM cells were treated with si-AEG-1 or si-CCR5 and then subjected to in vitro assays. We observed that CCR5 and AEG-1 proteins were highly expressed in CM tissues (73.3 and 76.7%, respectively) and closely correlated with tumor size (>5 cm). Importantly, we validated the expression of AEG-1, p-Erk1/2, p-Akt, vimentin, N-cadherin and MMP2 increased in the CM cell with CCL3 treatment in a time- and concentration-dependent manner. When CM cells were treated with si-CCR5, the expression of AEG-1, p-Erk1/2, p-Akt, vimentin, N-cadherin and MMP2 was downregulated. In addition, when CM cells were treated with si-AEG-1, the expression of p-Erk1/2, p-Akt, vimentin, N-cadherin and MMP2 was also downregulated. Using the cell cycle and proliferation assay, the knockdown of AEG-1 inhibited the entry of G1 into S phase and the proliferation capacity of CM cells. In conclusion, AEG-1 mediates CCL3/CCR5-induced EMT development via both Erk1/2 and Akt signaling pathway in CM patients, which indicates CCL3/CCR5-AEG-1-EMT pathway could be suggested as a useful target to affect the progression of CM.