Association between gut microbiota and malignant cardiac tumors: A two-sample Mendelian randomization study.

BACKGROUND: Recent studies provide compelling evidence linking the gut microbiota to most cancers. Nevertheless, further research is required to establish a definitive causal relationship between the gut microbiota and malignant cardiac tumors. METHODS: The genome-wide association studies (GWAS) data on the human gut Microbiota, included in the IEU Open GWAS project, was initially collected by the MiBioGen consortium. It encompasses 14,306 individuals and comprises a total of 5,665,279 SNPs. Similarly, the GWAS data on malignant cardiac tumors, also sourced from the IEU Open GWAS project, was initially stored in the finnGen database, including 16,380,303 SNPs observed within a cohort of 174,108 individuals within the European population. Utilizing a two-sample Mendelian randomization (MR) methodology, we examined whether there exists a causal association between the gut microbiota and cardiac tumors. Additionally, to bolster the credibility and robustness of the identified causal relationships, we conducted an extensive array of sensitivity analyses, encompassing Cochran's Q test, MR-PRESSO tests, MR-Egger interpret test, directionality test and leave-one-out analysis. RESULTS: Our analysis unveiled seven distinct causal associations between genetic susceptibility in the gut microbiota and the incidence of malignant cardiac tumors. Among these, the Family Rikenellaceae, genus Eubacterium brachy group, and genus Ruminococcaceae UCG009 exhibited an elevated risk of cardiac tumors, while the phylum Verrucomicrobia, genus Lactobacillus, genus Ruminiclostridium5, and an unknown genus id.1868 were genetically linked to a reduced risk of cardiac tumors. The causal relationship between these two bacteria, belonging to the phylum Verrucomicrobia (OR = 0.178, 95% CI: 0.052-0.614, p = 0.006) and the genus Ruminococcaceae UCG009 (OR = 3.071, 95% CI: 1.236-7.627, p = 0.016), and cardiac tumors was further validated through sensitivity analyses, reinforcing the robustness and reliability of the observed associations. CONCLUSION: Our MR analysis confirms that the phylum Verrucomicrobia displays significant protection against cardiac tumor, and the genus Ruminococcaceae UCG009 leads to an increasing risk of cardiac tumor.

Diagnosis and cardiac transplantation of a Carney syndrome-induced cardiac myxoma combined with dilated cardiomyopathy: a case report.

BACKGROUND: Carney syndrome is an uncommon autosomal disorder closely linked to mutations in the PRKAR1A gene. Skin lesions are the most pronounced feature of Carney syndrome, affecting over 80% of individuals with this condition. This syndrome is characterized by a triad of myxomas, skin pigmentation, and endocrine hyperfunction, featuring multiple endocrine neoplasms with skin and cardiac involvement. Dilated cardiomyopathy, a primary cardiomyopathy, is defined as the dilation and impaired systolic function of the left or both ventricles. Its clinical presentation varies from being asymptomatic to heart failure or sudden cardiac death, making it a leading global cause of heart failure. Currently, Dilated cardiomyopathy has an estimated prevalence of 1/2500-1/250 individuals, predominantly affecting those aged 30-40 years, with a male-to-female ratio of 3:1. This case report describes a heart failure patient with cardiac myxoma caused by Carney syndrome combined with dilated cardiomyopathy. The patient was successfully treated for heart failure by heart transplantation. CASE PRESENTATION: Herein, we report a case of heart failure due to Carney syndrome that resulted in cardiac myxoma combined with dilated cardiomyopathy. A 35-year-old male was admitted to the hospital three years ago because of sudden chest tightness and shortness of breath. Echocardiography indicated myxoma, and a combination of genetic screening and physical examination confirmed Carney syndrome with cardiac myxoma. Following symptomatic management, he was discharged. Surgical interventions were not considered at the time. However, the patient's chest tightness and shortness of breath symptoms worsened, and he returned to the hospital. A New York Heart Association grade IV heart function was confirmed, and echocardiography indicated the presence of dilated cardiomyopathy accompanied by cardiac myxoma. Ultimately, the patient's heart failure was successfully treated with heart transplantation. CONCLUSIONS: Cardiac myxoma caused by Carney syndrome combined with heart failure caused by dilated cardiomyopathy can be resolved by heart transplantation.

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.

[Primary cardiac synovial sarcoma: a clinicopathological analysis of five cases].

Objective: To assess the clinicopathological features, immunophenotype, molecular characteristics and differential diagnosis of primary cardiac synovial sarcoma (PCSS). Methods: Five cases of PCSS were collected at Guangdong Provincial People's Hospital from 2008 to 2023, and their clinicopathological features were summarized. Immunohistochemical staining, fluorescence in-situ hybridization (FISH) and next-generation sequencing (NGS) were performed, and relevant literatures were reviewed. Results: The cases were found in four males and one female, ranging in ages from 16 to 51 years (median 30 years). Two cases were located in the pericardium, two in the right ventricle, and one in the left ventricle. Follow-up data were available in four cases. All the four patients died of disease at 3, 7, 13 and 26 months, respectively, after diagnosis. The tumor maximum diameter ranged from 6.0 to 14.0 cm in (mean 10.0 cm). Microscopically, three cases were monophasic and two cases were biphasic. Immunohistochemically, all cases were immunoreactive for EMA, vimentin, bcl-2 and CD56. The tumor cells were variably positive for pan-cytokeratin, SS18-SSX, SOX2, TLE1, CD99, synaptophysin, calretinin and calponin. FISH showed the presence of SS18 rearrangement in all the cases. NGS detected SS18-SSX gene fusion in three cases (SS18-SSX1 in one and SS18-SSX2 in two). Conclusions: PCSS is an exceedingly rare neoplasm, and should be distinguished from other various malignant epithelial and mesenchymal tumors. The clinical history, histopathological and immunohistochemical features, and molecular findings are all essential to the definitive diagnosis of PCSS.

Frequent protein kinase A regulatory subunit A1 mutations but no GNAS mutations as potential driver in sporadic cardiac myxomas.

PURPOSE: Cardiac myxomas (CMs) are the second most common benign primary cardiac tumors, mainly originating within the left atrium. Approximately 5% of CM cases are associated with Carney Complex (CNC), an autosomal dominant multiple neoplasia syndrome often caused by germline mutations in the protein kinase A regulatory subunit 1A (PRKAR1A). Data concerning PRKAR1A alterations in sporadic myxomas are variable and sparse, with PRKAR1A mutations reported to range from 0% to 87%. Therefore, we investigated the frequency of PRKAR1A mutations in sporadic CM using next-generation sequencing (NGS). Additionally, we explored mutations in the catalytic domain of the Protein Kinase A complex (PRKACA) and examined the presence of GNAS mutations as another potential driver. METHODS AND RESULTS: This study retrospectively collected histological and clinical data from 27 patients with CM. First, we ruled out the possibility of underlying CNC through clinical evaluations and standardized interviews for each patient. Second, we performed PRKAR1A immunohistochemistry (IHC) analysis and graded the reactivity of myxoma cells semi-quantitatively. NGS was then applied to analyze the coding regions of PRKAR1A, PRKACA, and GNAS in all 27 cases. Of the 27 sporadic CM cases, 13 (48%) harbored mutations in PRKAR1A. Among these 13 mutant cases, six displayed more than one mutation in PRKAR1A. Most of the identified mutations resulted in premature stop codons or affected splicing. In PRKAR1A mutant CM cases, the loss of PRKAR1A protein expression was significantly more common. In two cases with missense mutations, protein expression remained preserved. Furthermore, a single mutation was detected in the catalytic domain of the protein kinase A complex, while no GNAS mutations were found. CONCLUSION: We identified a relatively high frequency of PRKAR1A mutations in sporadic CM. These PRKAR1A mutations may also represent an important oncogenic mechanism in sporadic myxomas, as already known in CM cases associated with CNC.

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.

Clinical outcomes of fetuses with cardiac rhabdomyoma: A case series from a tertiary center.

AIMS: The study aims to evaluate the genetic and clinical outcomes of fetal cardiac rhabdomyoma in our tertiary center. METHODS: Data of cases with cardiac rhabdomyoma detected by fetal echocardiography during antenatal follow-up were analyzed retrospectively. RESULTS: Nine cases were included in the study. The incidence of cardiac rhabdomyoma was 0.003%. The median fetal diagnosis time was 26th weeks, the most common location was the LV. There was no hemodynamic disorder requiring cardiovascular intervention in any of the cases. Of the eight genetically tested cases, four were tuberous sclerosis complex (TSC) gene-negative, one hereditary TSC2, one de novo TSC1, and two de novo TSC2 gene mutants. Postnatal first-year survival rate of the cases was 88.8%. CONCLUSIONS: Cardiac rhabdomyoma is a rare fetal and pediatric pathology that generally is a remarkable finding in the clinical process of TSC. Therefore, cases should be evaluated multisystemically and genetic counseling should be given to the family.

Genetics of Cardiac Tumours: A Narrative Review.

Cardiac tumours can occur in association with genetic syndromes. Rhabdomyomas have been reported in association with tuberous sclerosis, myxomas with Carney's complex, cardiac fibromas with Gorlin syndrome, and paragangliomas with multiple endocrine neoplasm syndrome. The presentation and prognosis of cardiac tumours associated with genetic syndromes differ compared with sporadic cases. Knowledge about the associated syndromes' genetic features and extracardiac manifestations is essential for the diagnosis, prognosis, and management of cardiac neoplasms. Moreover, identifying genetic mutations in benign and malignant cardiac tumours is needed to personalise management and improve treatment outcomes. Thus, this review discusses the genetic abnormalities associated with cardiac tumours, the current genetic screening recommendations, and the effect of those genetic mutations on the outcomes.

The role of single-cell RNA sequencing in cardiac tumour - a case report.

A 65-year-old woman presented to our hospital with 5 days of chest tightness, dyspnoea, and lower abdominal distension. Echocardiography revealed a mass in the right atrium. An emergency operation was carried out to prevent tumour shedding. The patient was discharged on the 4th day of tumour resection, without any complications At the 18 months follow-up, she suffered from kidney and lung tumours. She refused any treatment and passed away. scRNA-seq was applied to analyse the nature of the tumour. The cellular components of benign tumours include chondrocytes, smooth muscle cells, fibroblasts, mesenchymal stromal cells, and osteoblasts. Additionally, the cyclic guanosine monophosphate (cGMP-PKG) signalling pathway, transcriptional misregulation in cancer, and the p53 signalling pathway may be related to the growth of this tumour. scRNA-seq is a good approach to analyse growth patterns of cardiac tumours and helpful for distinguishing the nature of the tumour.

The benign nature and rare occurrence of cardiac myxoma as a possible consequence of the limited cardiac proliferative/ regenerative potential: a systematic review.

BACKGROUND: Cardiac Myxoma is a primary tumor of heart. Its origins, rarity of the occurrence of primary cardiac tumors and how it may be related to limited cardiac regenerative potential, are not yet entirely known. This study investigates the key cardiac genes/ transcription factors (TFs) and signaling pathways to understand these important questions. METHODS: Databases including PubMed, MEDLINE, and Google Scholar were searched for published articles without any date restrictions, involving cardiac myxoma, cardiac genes/TFs/signaling pathways and their roles in cardiogenesis, proliferation, differentiation, key interactions and tumorigenesis, with focus on cardiomyocytes. RESULTS: The cardiac genetic landscape is governed by a very tight control between proliferation and differentiation-related genes/TFs/pathways. Cardiac myxoma originates possibly as a consequence of dysregulations in the gene expression of differentiation regulators including Tbx5, GATA4, HAND1/2, MYOCD, HOPX, BMPs. Such dysregulations switch the expression of cardiomyocytes into progenitor-like state in cardiac myxoma development by dysregulating Isl1, Baf60 complex, Wnt, FGF, Notch, Mef2c and others. The Nkx2-5 and MSX2 contribute predominantly to both proliferation and differentiation of Cardiac Progenitor Cells (CPCs), may possibly serve roles based on the microenvironment and the direction of cell circuitry in cardiac tumorigenesis. The Nkx2-5 in cardiac myxoma may serve to limit progression of tumorigenesis as it has massive control over the proliferation of CPCs. The cardiac cell type-specific genetic programming plays governing role in controlling the tumorigenesis and regenerative potential. CONCLUSION: The cardiomyocytes have very limited proliferative and regenerative potential. They survive for long periods of time and tightly maintain the gene expression of differentiation genes such as Tbx5, GATA4 that interact with tumor suppressors (TS) and exert TS like effect. The total effect such gene expression exerts is responsible for the rare occurrence and benign nature of primary cardiac tumors. This prevents the progression of tumorigenesis. But this also limits the regenerative and proliferative potential of cardiomyocytes. Cardiac Myxoma develops as a consequence of dysregulations in these key genes which revert the cells towards progenitor-like state, hallmark of CM. The CM development in carney complex also signifies the role of TS in cardiac cells.

Crosstalk between KIF1C and PRKAR1A in left atrial myxoma.

Cardiac myxoma (CM) is the most common benign cardiac tumor, and most CMs are left atrial myxomas (LAMs). Six variations of KIF1C, c.899 A > T, c.772 T > G, c.352 A > T, c.2895 C > T, c.3049 G > A, and c.*442_*443dup in left atrial myxoma tissues are identified by whole-exome sequencing (WES) and Sanger sequencing. RNA-seq and function experiments show the reduction of the expression of KIF1C and PRKAR1A caused by rare variations of KIF1C. KIF1C is observed to be located in the nucleus, bind to the promoter region of PRKAR1A, and regulate its transcription. Reduction of KIF1C decreases PRKAR1A expression and activates the PKA, which causes an increase in ERK1/2 phosphorylation and SRC-mediated STAT3 activation, a reduction of CDH1, TP53, CDKN1A, and BAX, and eventually promotes tumor formation both in vitro and in vivo. The results suggest that inhibition of KIF1C promotes the pathogenesis of LAM through positive feedback formed by the crosstalk between KIF1C and PRKAR1A.

Primary cardiac sarcomas: A clinicopathologic study in a single institution with 25 years of experience with an emphasis on MDM2 expression and adjuvant therapy for prognosis.

BACKGROUND: Primary cardiac sarcomas are rare and their clinicopathologic features are heterogeneous. Among them, particularly intimal sarcoma is a diagnostic challenge due to nonspecific histologic features. Recently, MDM2 amplification reported to be a characteristic genetic event in the intimal sarcoma. In this study, we aimed to identify the types and incidence of primary cardiac sarcomas that occurred over 25 years in tertiary medical institutions, and to find clinicopatholgical significance through reclassification of diagnoses using additional immunohistochemistry (IHC). METHODS: We reviewed the primary cardiac sarcoma cases between January 1993 and June 2018 at Asan Medical Center, South Korea, with their clinicopathologic findings, and reclassified the subtypes, especially using IHC for MDM2 and then, analyzed the significance of prognosis. RESULTS: Forty-eight (6.8%) cases of a primary cardiac sarcoma were retrieved. The tumors most frequently involved the right atrium (n = 25, 52.1%), and the most frequent tumor subtype was angiosarcoma (n = 23, 47.9%). Seven cases (53.8%) were newly reclassified as an intimal sarcoma by IHC for MDM2. Twenty-nine (60.4%) patients died of disease (mean, 19.8 months). Four patients underwent a heart transplantation and had a median survival of 26.8 months. This transplantation group tended to show good clinical outcomes in the earlier stages, but this was not statistically significant (p = 0.318). MDM2 positive intimal sarcoma showed the better overall survival (p = 0.003) than undifferentiated pleomorphic sarcoma. Adjuvant treatment is beneficial for patient survival (p < 0.001), particularly in angiosarcoma (p < 0.001), but not in intimal sarcoma (p = 0.154). CONCLUSION: Our study supports the use of adjuvant treatment in primary cardiac sarcoma, as it was associated with a significantly better overall survival rate. Further consideration of tumor histology may be important in determining the optimal use of adjuvant treatment for different types of sarcomas. Therefore, accurate diagnosis by MDM2 test is important condsidering patient's prognosis and treatment.

Study on prenatal diagnosis and pregnancy outcome analysis of fetuses with cardiac rhabdomyoma.

OBJECTIVE: To investigate the prenatal imaging characteristics, genetic characteristics and pregnancy outcome of fetuses with cardiac rhabdomyoma. STUDY DESIGN: The prenatal ultrasound, cranial MRI imaging information and genetic test results of 35 fetuses prenatally diagnosed with cardiac rhabdomyoma were collected and retrospectively analyzed, and the pregnancy outcome was followed up. RESULT: Cardiac rhabdomyomas mainly occurred in left ventricular wall and ventricular septum; cranial MRI imaging was found abnormal in 38.1% (8/21) of the fetuses; genetic test was found abnormal in 58.82% (10/17) of the fetuses; the fetus was born in 12 cases and the pregnancy was terminated in 23 cases. CONCLUSION: TRIO whole exome sequencing (TrioWES) is recommended as the genetic test regime for cardiac rhabdomyoma. The comprehensive evaluation of prognosis of fetuses needs to consider the genetic results and whether the brain is involved; the prognosis of fetuses with simple cardiac rhabdomyoma is good.

Recurrent Tumor Suppressor Alterations in Primary Pericardial Mesothelioma.

Primary pericardial mesotheliomas are extremely rare, accounting for <1% of all mesotheliomas, and their molecular genetic features and predisposing factors remain to be determined. Here, we report the clinicopathologic, immunohistochemical, and molecular genetic findings of 3 pericardial mesotheliomas without pleural involvement. Three cases diagnosed between 2004 and 2022 were included in the study and analyzed by immunohistochemistry and targeted next-generation sequencing (NGS); corresponding nonneoplastic tissue was sequenced in all cases. Two patients were female and 1 was male, aged between 66 and 75 years. Two patients each had prior asbestos exposure and were smokers. Histologic subtypes were epithelioid in 2 cases and biphasic in 1 case. Immunohistochemical staining identified expression of cytokeratin AE1/AE3 and calretinin in all cases, D2-40 in 2 cases, and WT1 in 1 case. Staining for tumor suppressors revealed loss of p16, MTAP, and Merlin (NF2) expression in 2 cases and loss of BAP1 and p53 in 1 case. Abnormal cytoplasmic BAP1 expression was observed in an additional case. Protein expression abnormalities correlated with NGS results, which showed concurrent complete genomic inactivation of CDKN2A/p16, CDKN2B, MTAP, and NF2 in 2 mesotheliomas and of BAP1 and TP53 in 1 mesothelioma each, respectively. In addition, 1 patient harbored a pathogenic BRCA1 germline mutation, which resulted in biallelic inactivation in the mesothelioma. All mesotheliomas were mismatch repair proficient and showed several chromosomal gains and losses. All patients died from disease. Our study demonstrates that pericardial mesotheliomas share common morphologic, immunohistochemical, and molecular genetic features with pleural mesothelioma, including recurrent genomic inactivation of canonical tumor suppressors. Our study adds new insights into the genetic landscape of primary pericardial mesothelioma and highlights BRCA1 loss as a potential contributing factor in a subset of cases, thereby contributing to refined precision diagnostics for this rare cancer.

Fetal neurosonography as accurate tool for diagnosis of brain involvement in tuberous sclerosis.

OBJECTIVE: To demonstrate the potential utility of dedicated neurosonography for the diagnosis of fetal brain involvement in tuberous sclerosis complex. METHODS: This was a multicenter retrospective study of fetuses at high risk for tuberous sclerosis complex. Dedicated neurosonographic, fetal magnetic resonance imaging (MRI) and postnatal reports were reviewed. Data collected included reason for referral, gestational age at which cardiac rhabdomyoma was first suspected and final number of cardiac rhabdomyomas detected on dedicated imaging. We searched for tuberous sclerosis complex-related brain involvement, defined as the presence of one or more of the following findings: white-matter lesions; subependymal nodules; cortical/subcortical tubers; and subependymal giant-cell astrocytoma. RESULTS: We included 20 patients at high risk of tuberous sclerosis complex, of whom 19 were referred for the presence of cardiac rhabdomyomas and one for a deletion in chromosome 16 involving the tuberous sclerosis complex gene locus. Cardiac rhabdomyomas were diagnosed at a mean gestational age of 27 + 2 weeks (range, 16 + 0 to 36 + 3 weeks) and the mean number of cardiac rhabdomyomas per patient was 4 (range, 1-10). Brain involvement was present in 15 fetuses, in 13 of which the disease was confirmed in one or more of the following ways: chromosomal microarray analysis (n = 1), exome sequencing (n = 7), autopsy (n = 4), clinical tuberous sclerosis complex in the newborn (n = 4) and a sibling diagnosed with clinical tuberous sclerosis complex (n = 1). In two cases, the disease could not be confirmed: one was lost to follow-up and autopsy, following termination of pregnancy, was not performed in the other. Among the five cases without brain findings, tuberous sclerosis complex was confirmed in three by exome sequencing (n = 2) and/or autopsy findings (n = 2). The two remaining cases had normal exome sequencing; one case had five cardiac rhabdomyomas, which was a highly suggestive finding, while in the final case, the autopsy was considered normal, representing the only false-positive case in our cohort. CONCLUSIONS: Contrary to current literature, dedicated neurosonography appears to be effective in the diagnosis of brain involvement in fetuses at risk of tuberous sclerosis complex and should be used as the first-line approach. Although the number of cases in which MRI was performed was small, it seems that, in the presence of ultrasound findings, the added value of MRI is low. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Isolated Cardiac Paraganglioma Encasing Right Coronary Artery With Evidence of Succinyl Dehydrogenase Gene Mutation: Successful Management Using Multimodality Imaging.

This report involves a young woman with isolated cardiac paraganglioma that was diagnosed using 68Gallium-labeled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-NaI3-octreotide positron emission tomographic scintigraphy. For the preoperative evaluation, multimodality imaging accurately described the anatomic location of the tumor and its relationship with the surrounding tissues. The patient underwent successful surgical resection of the tumor along with right coronary artery bypass grafting. The 2-month follow-up scintigraphy was normal. Next-generation sequencing evaluation revealed a novel germline mutation for the succinate dehydrogenase subunit B gene.

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.

Genetic insights into cardiac tumors: a comprehensive review.

Cardiac neoplasms are rare, however, also a curable form of the disease once detected early. In recent years the viscus tumors have gained their highlights, due to the advancement in techniques like echocardiography both 2D and 3D, MRI, etc. These cardiac tumors are divided based on their benign and malignant nature and also as well as primary and secondary cardiac tumors. Largely the primary cardiac tumors are often than secondary cardiac tumors. The secondary tumor happens anywhere in the body involving the heart. The most common malignant tumors are sarcoma, some are angiosarcomas, fibromas, rhabdosarcoma, and leiomyosarcoma. The primary sarcoma affects both men and women at an equal rate with non-specific symptoms. These conditions led to high demand in genomic testing that helps in spot the mutation that leads to the particular type of cardiac neoplasm and it additionally helps to screen the mutated sequence and stop it from being inherited. Recent studies on cardiac tumors have revealed many genes that are involved in tumorigenesis and technologies have enabled the right screening of the tumor location within the heart and their histopathological studies were also studied. This review principally focuses on the understanding of the various forms of cardiac tumors, genetic variants involved and their influence, genetic testing, and different diagnostic approaches in cardiac tumors.

[Clinicopathological characteristics and molecular alterations of primary cardiac leiomyosarcoma: report of five cases].

Objective: To investigate the clinical, pathologic and radiologic features and molecular alterations in patients with primary cardiac leiomyosarcoma (PCLMS). Methods: Five cases of PCLMS were collected in Beijing Anzhen Hospital from January 2016 to December 2020. The clinical, pathologic and radiologic data, and molecular alterations were analyzed, and the patients were followed up. Results: All five patients were female, and had no history of leiomyosarcoma in other parts of the body. The age of patients ranged from 37 to 62 years (median 47 years). The main clinical symptoms were chest pain and dyspnea, one also presented with palpitation and lower limb weakness and one with dizziness. Two tumors were located in the left atrium, two in the right atrium, and one in the right ventricle, and they maximal diameter ranged from 2.5 to 14.0 cm (mean 6.2 cm). The neoplasms presented as medium-echo masses with a broad base in the echocardiography, and as a low-density, solid mass when detected by contrast-enhanced CT. Histologically, two tumors were well-differentiated and three were moderately and poorly differentiated, and two included extensive, loose myxoid stroma. Immunohistochemical staining showed that PCLMS was positive for SMA, desmin, MDM2, and epidermal growth factor receptor. Fluorescence in situ hybridization showed ALK gene rearrangement in two cases, and COL1A1-PDGFB fusion in three cases. All cases received surgical excision and two cases received chemotherapy. Three patients died within 0-11 months (mean survival of 7.7 months) and two patients were alive. Conclusions: PCLMS is a malignant tumor with a high recurrence rate and poor prognosis. These cases may provide useful information to improve the diagnosis and management of PCLMS.