[Aggresive angiomyxoma after renal transplantation]. / Angiomixoma agresivo postrasplante renal.

The condition of immunosuppressed increases the risk of cancer in kidney transplant patients, as compared to the general population. The best survival of inmunosupressed patients in recent years has turned both neoplasms and cardiovascular diseases into the main causes of morbidity and mortality. We present the case of a renal transplanted patient who developed an unusual form of mesenchymal tumor such as the aggressive angiomyxoma, four years after the implant and requiring wide surgical resection.

[Asymptomatic Cardiac Myxoma Complicated with Carney Complex;Report of a Case].

Carney complex(CNC) is a rare genetic syndrome, characterized by spotty pigmentation of the skin, cardiac myxomas and multiple endocrine tumors. We present a case of asymptomatic cardiac myxoma associated with CNC. She was 49 year-old healthy woman whose son was known to have CNC. She was also diagnosed as CNC due to her family history, typical cutaneous findings and screening endocrine test. Screening ultrasound echocardiography resulted in discovering her asymptomatic left atrial myxoma of 30 mm size. Tumor was successfully resected via median sternotomy and no signs of recurrence were observed at 1 year follow up. Periodical follow up is mandatory because of its high recurrence rate.

Inherited disposition to cardiac myxoma development.

Carney complex is a genetic condition in which affected individuals develop benign tumours in various tissues, including the heart. Most individuals with Carney complex have a mutation in the PRKAR1A gene, which encodes the regulatory R1alpha subunit of protein kinase A - a significant component of the cyclic-AMP signalling pathway. Genetically engineered mutant Prkar1a mouse models show an increased propensity to develop tumours, and have established a role for R1alpha in initiating tumour formation and, potentially, in maintaining cell proliferation. Ongoing investigations are exploring the intersection of R1alpha-dependent cell signalling with other gene products such as perinatal myosin, mutation of which can also cause cardiac myxomas.

Two cases of right atrial myxoma in redo patients. A mere coincidence?

We describe two cases of right atrial myxoma in redo patients who had previously undergone to coronary artery by-pass grafting (CABGs) and mitral valve replacement respectively. Both of patients experienced effort dyspnea and were assessed by trans-thoracic echocardiography, revealing the right atrial masses. They were operated on for myxoma resection and postoperative course was uneventful. Our report deals with the interesting topic of the location of benign masses that are usually more common in the left atrium. Should we hypothesize that the right atrial manipulation during the previous surgery induces the onset of the right atrial mass? It is an interesting matter to debate.

Myxoma developing after open heart surgery: is radiofrequency ablation responsible for the formation of the tumor?

34-year-old male with history of recurrent atrial fibrillation (AF) and mitral stenosis, status post radiofrequency ablation (RFA) and prosthetic mitral valve replacement two years earlier was admitted with prosthetic valve thrombosis for redo mitral valve surgery. During the surgery, a 2 x 1.5 x 1 cm mass was identified on the interatrial septum, attached to the edge of tricuspid valve's septal leaflet by a stalk. The mass was excised and histological evaluation revealed myxoma. It is accepted that myxomas can develop after cardiac trauma. It is known that RFA for AF increases the risk of thrombus or endocarditis in the atrium. Herein, we report a myxoma case where we think the heat energy caused by RFA might have triggered the development of the tumor.

Vascular tangle in the inter-atrial septum - Is it the source of cardiac myxoma?

BACKGROUND: Cardiac myxomas (CMs) are the most common primary tumors of the heart, said to be derived from pluripotent cardiac stem cells. They are most often attached to the left side of the inter-atrial septum (IAS) and a feature noted at the site of attachment is a conglomeration of thick-walled vessels that has been noted to precede the development of myxomas. AIMS: The present study was conducted to compare histology of the normal inter-atrial septa to the septal flap excised with the myxomas and to evaluate the significance of this 'vascular tangle' in the histogenesis of these tumors. MATERIALS AND METHODS: In a 10-year retrospective analysis of all surgically excised CMs, tumors with attached septal sleeves were selected. This histology was compared to the serial sections of 25 normal age-matched septa obtained from normal hearts at autopsy. RESULTS: Of the 56 myxomas seen in 10 years, 38 tumors (all left atrial in location) were received with a flap of the IAS. All of these cases, irrespective of the sizes of the tumor, showed the presence of conglomeration of thick-walled blood vessels, many of which showed abrupt myxoid change in their walls. Another noteworthy feature in many vessels in all flaps was migration of the myxoid tissue through the vascular walls and the endocardium to mushroom out into the atrial lumen. Such vascular channels were not seen in any of the normal IAS. CONCLUSIONS: Based on these findings, we propose a two-step hypothesis: an initial step that stimulates the pluripotent cells toward vasculogenesis with endothelial and smooth muscle differentiation, and a subsequent step leads to production of abundant mucopolysaccharides that splay apart the smooth muscle cells, which would explain rings, cords or nests of myxoma cells around endothelial lined spaces.

Surgical treatment of primary intracranial myxoma in a child following radiotherapy: case report and review of the literature.

INTRODUCTION: Myxomas are benign tumors of the mesenchymal origin and account for about half of the benign cardiac tumors. Occasionally, they occur at other locations, but the intracranial manifestation of a myxoma is exceptionally rare. As a secondary neoplasia following radiotherapy, myxoma has only been reported once in the literature. MATERIAL AND METHODS: A 12-year-old girl, who was previously treated for a medulloblastoma, was diagnosed with a new lesion at the left transverse sinus in the follow-up magnetic resonance imaging (MRI). Indication for surgery was made and complete removal could be achieved. RESULTS AND DISCUSSION: Histological examination revealed a myxoma. Further staging showed no other manifestation of the myxoma. The close relation to the radiation field of the posterior fossa makes it highly suggestive that the myxoma developed as a secondary neoplasia induced by radiotherapy. Treatment philosophy for this benign tumor entity is a completed resection of the lesion with regular follow-up MRI.

Superficial angiomyxoma in a pregnant cow.

A 3-year-old, pregnant, Alpine Brown cow showed a rapidly growing, pedunculated, skin mass located at the umbilical region, reaching 8 kg in weight over a 3-month period after its initial detection. Six days after parturition, the mass was completely surgically excised. During the follow-up period, the cow remained in good health, without signs of recurrence, and showed increased milk production. Histological examination of the mass revealed a loose proliferation of spindle-shaped or stellate cells, immersed in an abundant myxoid matrix with admixed numerous thin-walled blood vessels. Immunohistochemically, the tumour cells were positive for vimentin, α-smooth muscle actin, and desmin. Gross and histopathological features were compatible with superficial angiomyxoma, a subtype of angiomyxoma rarely described in humans, but not in the veterinary literature. The tumour did not infiltrate into the surrounding tissues, and there was no post-excision recurrence after 3 months. The possibility of hormonal dependence of the tumour during pregnancy is discussed based on such findings in some human cases.

Cardiac Myxoma Caused by Fumarate Hydratase Gene Deletion in Patient With Cortisol-Secreting Adrenocortical Adenoma.

CONTEXT: Germline mutations in fumarate hydratase (FH) gene are known to cause hereditary leiomyomatosis and renal cell carcinoma (HLRCC) and are occasionally accompanied with cutaneous and uterine leiomyoma or cortisol-producing adrenocortical hyperplasia. However, the association between FH mutations and cardiac or adrenocortical tumors has remained unknown. Here, we identified a novel deletion in FH, exhibiting cardiac myxoma and subclinical Cushing syndrome due to adrenocortical tumor. CASE DESCRIPTION: A 44-year-old man was referred to our hospital for cardiac and adrenal tumor evaluation. He had a history of multiple painful, dermal papules and nodules diagnosed as cutaneous leiomyoma. The surgically resected cardiac tumor was diagnosed as myxoma. The adrenal tumor was clinically diagnosed as subclinical Cushing syndrome. Laparoscopically resected adrenal tumor was pathologically diagnosed as adrenocortical adenoma harboring unique histological findings similar to primary pigmented nodular adrenocortical disease (PPNAD). DNA analysis revealed a germline deletion in FH c0.737delT (p. Phe225Leufs*31) and loss of heterozygosity (LOH) in cardiac myxoma. As a functional analysis of FH in cardiac myxoma, low FH protein expression with elevated 2-succinocysteine (2SC), a marker of FH dysfunction, was immunohistochemically detected. However, in adrenocortical tumor, LOH of FH was not detected, and FH or 2SC expression was not altered. CONCLUSIONS: This is the first case of HLRCC complicated by cardiac myxoma. LOH of FH deletion and its dysfunction were identified in cardiac myxoma. The association between FH deletion and adrenocortical lesion, however, needs to be further clarified.

Cardiac myxoma after treatment for childhood neuroblastoma.

An asymptomatic 13 year old with a history of neuroblastoma treated with chemotherapy, radiation therapy, and autologous bone marrow transplant was found to have a cardiac mass on screening echocardiogram. Surgical resection and histologic examination revealed the mass was a myxoma. After resection the patient made a full recovery. This report reviews the features of myxoma and explores the potential relationship between chemotherapy, radiation, bone marrow transplant and myxoma.

Cardiac myxoma: related to immunosuppression? A case report.

Cardiac myxomas are the most common type of primary cardiac tumours. Nevertheless, it is still a rare tumour and its relation with immunosuppressive therapy, which is essential after organ transplantation, remains uncertain. We report the case of a 30-year-old woman, who underwent kidney and pancreatic transplantation for severe nephropathy due to type I diabetes mellitus and since then, under heavy immunosuppressive treatment. Four years after surgery, a left atrial myxoma was discovered. Three other cases of cardiac myxomas following transplantation and immunodepressive status have been reported in the literature, which raises the question of an association between immunosuppression and the development of cardiac myxomas.

Heart myxoma develops oncogenic and metastatic phenotype.

PURPOSE: Heart myxomas have been frequently considered as benign lesions associated with Carney's complex. However, after surgical removal, myxomas re-emerge causing dysfunctional heart. METHODS: To identify whether cardiac myxomas may develop a metastatic phenotype as occurs in malignant cancers, a profile of several proteins involved in malignancy such as oncogenes (c-MYC, K-RAS and H-RAS), cancer-associated metabolic transcriptional factors (HIF-1α, p53 and PPAR-γ) and epithelial-mesenchymal transition proteins (fibronectin, vimentin, ß-catenin, SNAIL and MMP-9) were evaluated in seven samples from a cohort of patients with atrial and ventricular myxomas. The analysis was also performed in: (1) cardiac tissue surrounding the area where myxoma was removed; (2) non-cancer heart tissue (NCHT); and (3) malignant triple negative breast cancer biopsies for comparative purposes. RESULTS: Statistical analysis applying univariate (Kruskal-Wallis and Dunn's tests) and multivariate analyses (PCA, principal component analysis) revealed that heart myxomas (7-15 times) and myxoma surrounding tissue (22-99 times) vs. NCHT showed high content of c-MYC, p53, vimentin, and HIF-1α, indicating that both myxoma and its surrounding area express oncogenes and malignancy-related proteins as occurs in triple negative breast cancer. CONCLUSIONS: Based on ROC (receiver operating characteristics) statistical analysis, c-MYC, HIF-1α, p53, and vimentin may be considered potential biomarkers for malignancy detection in myxoma.

A rare cause of ischemic stroke: cardiac myxoma. Case report and review of literature.

A 46-year-old female diagnosed several years ago with arterial hypertension and an ischemic stroke with significant recovery was admitted for dyspnea on usual physical activity and fatigue. Physical examination revealed signs of heart failure with crackles on both lung bases, distented jugular veins, accentuated pulmonic valve closure (P2) and tricuspid regurgitation murmur. Echocardiography identified a large tumor in the left atrium, suggestive of atrial myxoma, which caused a severe functional mitral stenosis and produced severe pulmonary hypertension. A cardiac embolic source should always be checked in young patients with stroke. Atrial myxoma can mimic a variety of diseases: rheumatic mitral stenosis, infective endocarditis or autoimmune disease. A review on myxoma's histology, immunohistochemistry and genetics together with clinical aspects is presented.

Mutations in the protein kinase A R1alpha regulatory subunit cause familial cardiac myxomas and Carney complex.

Cardiac myxomas are benign mesenchymal tumors that can present as components of the human autosomal dominant disorder Carney complex. Syndromic cardiac myxomas are associated with spotty pigmentation of the skin and endocrinopathy. Our linkage analysis mapped a Carney complex gene defect to chromosome 17q24. We now demonstrate that the PRKAR1alpha gene encoding the R1alpha regulatory subunit of cAMP-dependent protein kinase A (PKA) maps to this chromosome 17q24 locus. Furthermore, we show that PRKAR1alpha frameshift mutations in three unrelated families result in haploinsufficiency of R1alpha and cause Carney complex. We did not detect any truncated R1alpha protein encoded by mutant PRKAR1alpha. Although cardiac tumorigenesis may require a second somatic mutation, DNA and protein analyses of an atrial myxoma resected from a Carney complex patient with a PRKAR1alpha deletion revealed that the myxoma cells retain both the wild-type and the mutant PRKAR1alpha alleles and that wild-type R1alpha protein is stably expressed. However, in this atrial myxoma, we did observe a reversal of the ratio of R1alpha to R2beta regulatory subunit protein, which may contribute to tumorigenesis. Further investigation will elucidate the cell-specific effects of PRKAR1alpha haploinsufficiency on PKA activity and the role of PKA in cardiac growth and differentiation.

Left Atrial Myxoma Following Coronary Artery Bypass Grafting with Patient Coronary Arterial Grafts: a Rarity.

The development of left atrial myxoma after coronary artery bypass graft surgery is a rare entity. A 60-year-old man with previous off-pump coronary artery bypass grafting four years ago with patent coronary grafts was diagnosed with left atrial mass. The patient underwent successful resection of the same through minimally invasive right anterolateral thoracotomy. Histopathology of the atrial mass confirmed the diagnosis of atrial myxoma.

Renal myxoma in a pediatric transplant recipient.

Renal myxoma is a very rare benign neoplasm seen almost exclusively in adults with only 16 reported cases in the literature. All of these cases have been reported in native kidneys with none being reported in a transplant kidney. We report the case of a renal myxoma in a 17-year-old boy's transplant kidney that was found as an incidental mass on ultrasonography and further evaluated with CT and PET scans. PET findings of a renal myxoma are reported here for the first time, and imaging findings from previous cases are briefly reviewed. This case report highlights the fact that adult-predominant tumors and pathology should always be a consideration in pediatric patients who receive organ transplants from adult donors.