Revealing the crucial roles of suppressive immune microenvironment in cardiac myxoma progression.

Cardiac myxoma is a commonly encountered tumor within the heart that has the potential to be life-threatening. However, the cellular composition of this condition is still not well understood. To fill this gap, we analyzed 75,641 cells from cardiac myxoma tissues based on single-cell sequencing. We defined a population of myxoma cells, which exhibited a resemblance to fibroblasts, yet they were distinguished by an increased expression of phosphodiesterases and genes associated with cell proliferation, differentiation, and adhesion. The clinical relevance of the cell populations indicated a higher proportion of myxoma cells and M2-like macrophage infiltration, along with their enhanced spatial interaction, were found to significantly contribute to the occurrence of embolism. The immune cells surrounding the myxoma exhibit inhibitory characteristics, with impaired function of T cells characterized by the expression of GZMK and TOX, along with a substantial infiltration of tumor-promoting macrophages expressed growth factors such as PDGFC. Furthermore, in vitro co-culture experiments showed that macrophages promoted the growth of myxoma cells significantly. In summary, this study presents a comprehensive single-cell atlas of cardiac myxoma, highlighting the heterogeneity of myxoma cells and their collaborative impact on immune cells. These findings shed light on the complex pathobiology of cardiac myxoma and present potential targets for intervention.

First report of a successful surgical management of left atrial myxoma coexisting with pulmonary squamous cell carcinoma and thymic cyst.

BACKGROUND: Primary cardiac tumors, while rare, present significant clinical challenges due to their diverse pathology and presentation. Lung cancer frequently metastasizes to the heart; however, cases involving primary cardiac tumors of different origins alongside primary lung cancer are exceedingly rare in the literature. CASE PRESENTATION: We report the case of a 53-year-old female who presented with hemoptysis and was subsequently diagnosed with a left atrial myxoma, pulmonary squamous cell carcinoma, and a thymic cyst. This coexistence of multiple non-homologous tumors in a single patient is exceedingly rare. CONCLUSION: This case underscores the complexity of diagnosing and managing patients with multiple distinct tumors. The simultaneous occurrence of a primary cardiac myxoma, pulmonary squamous cell carcinoma, and thymic cyst is unprecedented, providing valuable insights for future clinical practice.

Retrospective analysis of odontogenic myxoma and odontogenic myxofibroma in the oral and maxillofacial region: a fibrous tissue-related differentiation.

The clinical differences between odontogenic myxoma (OM) and odontogenic myxofibroma (OMF), and the clinical significance of their classifications, remain unclear. This study reviewed the clinicopathological characteristics of patients with OM or OMF and evaluated the fibrous component of the specimens. Medical records of 21 patients with OM or OMF who underwent tumour resection were reviewed. The percentage of fibrous tissue on the representative sections was evaluated using haematoxylin and eosin- and Masson's trichrome-stained specimens. Histopathological diagnoses included 11 OMs and 10 OMFs with no tumour recurrence except for two cases in which the dredging method was applied. More cortical bone perforation was observed in OM than in OMF cases, without significant differences. Location-locularity and apparent diffusion coefficient value (ADC)-cortical bone perforation were significantly correlated in all OM and OMF cases. The percentage of fibrous tissue in specimens showed bimodal distribution bordered by 45%. There was a significant association between diagnosis based on 45% fibrous tissue criterion and the final pathological diagnosis. Our study showed a tendency for cortical bone perforation in OM compared to OMF and correlation between ADC and cortical bone perforation. According to the histopathological analyses, the fibrous component of each case was bimodal with 45%, which may be a criterion to distinguish between OM and OMF. Accumulating knowledge, such as significant differences in prognosis, may allow for minimal surgical treatment options based on the diagnosis according to this novel histopathological criterion.

Glandular cardiac myxoma with intraepithelial ductal neoplasia features: Report of the first case.

Cardiac myxoma are the most common primary tumor of the heart in adults. In approximately 2-5%, glandular differentiation occurs within these tumors. In the presence of glandular features attention must be taken to exclude and prevent a misdiagnosis of cardiac metastases of adenocarcinoma. Nevertheless, the localization in the left atrium, the solitary disposition of the cardiac mass, the histological features and the immunohistochemistry performed, argued against the possibility of a metastatic nature of the tumor. We report the case of an 80-year-old woman, with a prior medical history of breast cancer, that underwent surgery for a cardiac myxoma that histologically showed glandular features. Herein, we highlight the importance of a careful diagnosis of this entity, as it can be easily confused for a metastasis, especially in patients with a history of malignancy.

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.

The Role of Methylation Analysis in Distinguishing Cellular Myxoma from Low-Grade Myxofibrosarcoma.

Cellular myxoma is a benign soft tissue tumor frequently associated with GNAS mutation that may morphologically resemble low-grade myxofibrosarcoma. This study aimed to identify the undescribed methylation profile of cellular myxoma and compare it to myxofibrosarcoma. We performed molecular analysis on twenty cellular myxomas and nine myxofibrosarcomas and analyzed the results using the methylation-based DKFZ sarcoma classifier. A total of 90% of the cellular myxomas had GNAS mutations (four loci had not been previously described). Copy number variations were found in all myxofibrosarcomas but in none of the cellular myxomas. In the classifier, none of the cellular myxomas reached the 0.9 threshold. Unsupervised t-SNE analysis demonstrated that cellular myxomas form their own clusters, distinct from myxofibrosarcomas. Our study shows the diagnostic potential and the limitations of molecular analysis in cases where morphology and immunohistochemistry are not sufficient to distinguish cellular myxoma from myxofibrosarcoma, particularly regarding GNAS wild-type tumors. The DKFZ sarcoma classifier only provided a valid prediction for one myxofibrosarcoma case; this limitation could be improved by training the tool with a more considerable number of cases. Additionally, the classifier should be introduced to a broader spectrum of mesenchymal neoplasms, including benign tumors like cellular myxoma, whose distinct methylation pattern we demonstrated.

Aggressive angiomyxoma of female pelvis and perineum: Retrospective study of 17 cases.

OBJECTIVE: Aggressive angiomyxoma is an uncommon mesenchymal neoplasm characterized by a high recurrence rate, usually observed in the lower genital tract of women during their reproductive age. STUDY DESIGN: Seventeen cases of aggressive angiomyxoma confirmed by pathology from January 2007 to December 2021 in Beijing Chao-yang Hospital were included. We collected clinical data and summarized the clinical and immunohistochemical features. RESULTS: All seventeen included patients were females, aged between 23 and 57 years (mean, 37.7 years; median, 42 years). Fourteen patients were newly diagnosed and three were recurrent. The tumors were located in vulva (58.8 %), vagina (23.5 %), buttock (11.8 %), and cervix (5.9 %). The tumors size were 2 to 15 cm in greatest dimension (mean 8 ± 4.4 cm, median 6 cm). Follow-up data was available for nine patients, which ranged from 25 to 124 months (mean, 82 months; median, 80 months). At the end of follow-up, no other recurrence or metastasis was reported. Immunohistochemical analysis showed immunoreactive for estrogen (10/11) and progesterone (8/11) receptor, desmin (6/8), smooth muscle actin (4/10), and vimentin (4/4), S-100 (1/8) and CD34 (1/7). The Ki67 level was less than 5 % in five cases. CONCLUSIONS: AAM is a hormone-sensitive, distinct rare mesenchymal neoplasm with high incidence of local recurrence. Surgery is the preferred treatment, with complete resection being an essential prerequisite for minimizing the risk of recurrence.

Conjunctival myxoma: A case report and review of a rare tumor.

RATIONALE: Conjunctival myxoma is a rare benign tumor, which can mimic more common conjunctival lesions such as a cyst, lymphangioma, amelanotic nevus, neurofibroma, amelanotic melanoma, or lipoma. We describe a patient with the conjunctival myxoma, who was initially misdiagnosed as a conjunctival cyst. This case report includes intraoperative photographs and various immunohistochemical staining images. PATIENTS CONCERNS: A 55-year-old woman presented with a painless mass in the superotemporal conjunctiva of the left eye, which she had noticed 1 month ago. The patient had no previous history of trauma or eye surgery. Slit-lamp examination revealed a well-circumscribed, freely movable, pinkish, semi-translucent mass on the temporal bulbar conjunctiva, suggestive of a conjunctival cyst. DIAGNOSES: Histopathological analysis showed stellate- and spindle-shaped cells within the loose myxoid stroma, confirming a diagnosis of conjunctival myxoma. INTERVENTIONS: The conjunctival lesion was completely excised under local anesthesia. OUTCOMES: After 4 months of follow-up, the patient remained in good health without recurrence of the conjunctival lesion and no evidence of any systemic abnormality. LESSONS: Myxoma is an extremely uncommon benign tumor derived from primitive mesenchyme. Considering the rarity of the tumor and its similarity to other conjunctival tumors, diagnosis can be challenging. Ophthalmologists should consider myxoma as a possible differential diagnosis when encountering conjunctival lesions. Surgical excision is essential to confirm the diagnosis and careful systemic evaluation is required to prevent potentially life-threatening underlying systemic conditions.

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.

Genetic characterization of intramuscular myxomas.

Introduction: Intramuscular myxomas are benign tumors that are challenging to diagnose, especially on core needle biopsies. Acquired chromosomal aberrations and pathogenic variants in codon 201 or codon 227 in GNAS complex locus gene (GNAS) have been reported in these tumors. Here we present our genetic findings in a series of 22 intramuscular myxomas. Materials and methods: The tumors were investigated for the presence of acquired chromosomal aberrations using G-banding and karyotyping. Pathogenic variants in codon 201 or codon 227 of GNAS were assessed using direct cycle Sanger sequencing and Ion AmpliSeq Cancer Hotspot Panel v2 methodologies. Results: Eleven tumors carried chromosomal abnormalities. Six tumors had numerical, four had structural, and one had both numerical and structural chromosomal aberrations. Gains of chromosomes 7 and 8 were the most common abnormalities being found in five and four tumors respectively. Pathogenic variants in GNAS were detected in 19 myxomas (86%) with both methodologies. The detected pathogenic variants were p.R201H in nine cases (seven with abnormal and two with normal karyotypes), p.R201C in five cases, all with normal karyotypes, p.R201S in three cases (two with abnormal and one with normal karyotype), p.R201G in one case with a normal karyotype, and p.Q227E in one case with a normal karyotype. Conclusion: Firstly, our data indicate a possible association between chromosomal abnormalities and GNAS pathogenic variants in intramuscular myxomas. Secondly, the presence of the rare pathogenic variants R201S, p.R201G and p.Q227E in 26% (5 out of 19) of myxomas with GNAS pathogenic variants shows that methodologies designed to detect only the common "hotspot" of p.R201C and p.R201H will give false negative results. Finally, a comparison between Ion AmpliSeq Cancer Hotspot Panel v2 and direct cycle Sanger sequencing showed that direct cycle Sanger sequencing provides a quick, reliable, and relatively cheap method to detect GNAS pathogenic variants, matching even the most cutting-edge sequencing methods.

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.

Incidental finding of atrial myxoma following curative treatment for paediatric neuroblastoma.

Cardiac tumours are uncommon in the general population and even more so in the paediatric population. Here we present a case of an asymptomatic 7-year-old male with history of high-risk neuroblastoma who underwent 1-year post-treatment surveillance scan with an incidental finding of intracardiac lesion found to be an atrial myxoma.

Carney complex: A clinicopathologic study on a single family from several Canadian provinces.

Carney syndrome is an autosomal dominant complex involving endocrinopathy, mucocutaneous hyperpigmentation, and different tumors, including cardiac myxomas. We report on a single family with several members affected with Carney syndrome. Family and individual medical histories were investigated in several Canadian provinces. The histology slides were also reviewed. Four family members (two young women, both sisters, their mother, and maternal grandmother) were found to harbor Carney syndrome. Everyone was presented with multiple and recurrent atrial myxomas of the heart, requiring multiple open cardiac surgeries. Breast myxomas and cutaneous hyperpigmentation were also revealed in one of the sisters and their mother. Interestingly, genetic testing was positive for the female family members and negative for the father and brother. We cannot rule out that the brother may have had a new mutation or harboring a mosaic. The young woman's brother did not have cardiac myxoma but developed a unilateral Sertoli cell tumor of testis. Carney syndrome is a rare complex multisystemic genetic disorder, including multiple and recurrent cardiac myxomas. We strongly suggest that reporting familial Carney syndrome is still critical in the 21st century to augment the awareness of this situation among clinicians and pathologists.

Aggressive Angiomyxoma of the Pelvis: 35-Year Experience.

BACKGROUND: Aggressive angiomyxoma is a very rare mesenchymal tumor most commonly found in the pelvic and perineal regions. Although many are estrogen and progesterone hormone receptor positive, the pathogenesis is unknown. Due to its rarity, there is a paucity of literature relating to this pathology. This article presents a case series on the management of aggressive angiomyxoma of the pelvis. OBJECTIVE: To present a 35-year experience managing aggressive angiomyxoma of the pelvis. DESIGN: This was a retrospective single-system analysis. SETTINGS: This study was conducted at a quaternary referral academic health care system. PATIENTS: All patients treated for aggressive angiomyxoma of the pelvis. INTERVENTIONS: All patients underwent surgical or medical management of their disease. MAIN OUTCOME MEASURES: The primary outcomes were disease recurrence and mortality. Secondary outcomes included risk factors for recurrence. RESULTS: A total of 32 patients (94% women) were identified with a median follow-up of 65 months. Thirty patients (94%) underwent operative resection and 2 patients were treated solely with medical management. Fifteen achieved an R0 resection (negative microscopic margins) at the index operation, of which 4 (27%) experienced tumor recurrence. There were no mortalities. No risk factors for disease recurrence were identified. LIMITATIONS: Limitations to our study include its nonrandomized retrospective nature, single health care system experience, and small patient sample size. CONCLUSIONS: Aggressive angiomyxoma is a rare, slow-growing tumor with locally invasive features and a high potential for recurrence even after resection with negative margins. Imaging modalities such as CT or MRI should be obtained to aid in diagnosis and surgical planning. Workup should be paired with preoperative biopsy and testing for hormone receptor status, which can increase diagnostic accuracy and guide medical treatment. Close posttreatment surveillance is imperative to detect recurrence. See Video Abstract . ANGIOMIXOMA AGRESIVO DE PELVIS EXPERIENCIA DE AOS: ANTECEDENTES:El angiomixoma agresivo es un tumor mesenquimal muy raro que se encuentra más comúnmente en las regiones pélvica y perineal. Aunque muchos son positivos para los receptores hormonales como el estrógeno y la progesterona, la patogénesis es aún desconocida. Debido a su rareza, existe escasa literatura relacionada con esta patología. Este artículo presenta una serie de casos sobre el tratamiento del angiomixoma agresivo de pelvis.OBJETIVO:Presentar una experiencia de 35 años en el manejo del angiomixoma agresivo de pelvis.DISEÑO:Este fue un análisis retrospectivo de sistema único.AJUSTES:Este estudio se llevó a cabo en un sistema de salud académico de referencia de nivel cuaternario.PACIENTES:Todos los pacientes tratados por angiomixoma agresivo de pelvis.INTERVENCIONES:Todos los pacientes se sometieron a tratamiento quirúrgico y/o médico de su enfermedad.PRINCIPALES MEDIDAS DE RESULTADO:Los resultados primarios fueron la recurrencia de la enfermedad y la mortalidad. Los resultados secundarios incluyeron factores de riesgo de recurrencia.RESULTADOS:Se identificaron un total de 32 pacientes (94% mujeres) con una mediana de seguimiento de 65 meses. Treinta (94%) fueron sometidos a resección quirúrgica y dos fueron tratados únicamente con tratamiento médico. Quince lograron una resección R0 (márgenes microscópicos negativos) en la operación inicial, de los cuales cuatro (27%) experimentaron recurrencia tumoral. No hubo mortalidades. No se identificaron factores de riesgo para la recurrencia de la enfermedad.LIMITACIONES:Las limitaciones de nuestro estudio incluyen su naturaleza retrospectiva no aleatoria, la experiencia de un solo sistema de atención médica y el tamaño pequeño de la muestra de pacientes.CONCLUSIONES:El angiomixoma agresivo es un tumor raro, de crecimiento lento, con características localmente invasivas y un alto potencial de recurrencia incluso después de una resección con márgenes negativos. Se deben obtener modalidades de imágenes como CT y/o MRI para la ayuda diagnóstica y la planificación quirúrgica. El estudio debe combinarse con una biopsia preoperatoria y pruebas del estado de los receptores hormonales, que pueden aumentar la precisión del diagnóstico y guiar el tratamiento médico. Es imperativa una estrecha vigilancia posterior al tratamiento para detectar recurrencia. (Traducción-Dr Osvaldo Gauto ).

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.