心脏粘液瘤的影像学诊断(附10例病例分析)

经手术病理证实的10例心脏粘液瘤,其中左房9例、右房1例。着重分析了粘液瘤的影像学表现。超声心动图检查对本病诊断具有决定性作用,X线平片检查可了解心肺的全面情况,故宜采用综合检查诊断手段。     

The problems of surgical treatment for cardiac myxoma and associated lesions

Twenty-four patients with cardiac myxomas consisting of 22 left and 2 right atrial myxomas were operated on. All myxomas were removed with an excision of the attachment walls using a cardiopulmonary bypass. Two myxomas required a partial cardiopulmonary bypass from the femoral vein to the artery prior to operation because they were on the verge of becoming stuck in the atrioventricular valves and potentially causing shock. For embolic complications of myxoma, the embolus of the external carotid artery was extirpated before undergoing cardiac surgery. In a patient with pulmonary infarction, the infarcted lung was resected simultaneously. Another patient with a cerebral infarction received a clipping of an aneurysm which later appeared in the infarcted area. For associated cardiac lesions, two patients underwent a coronary artery bypass graft and one mitral valve replacement with tricuspid annuloplasty. In the former two cases, the myxoma was removed prior to coronary artery bypass grafting because the use of retrograde coronary perfusion was considered to be sufficient to protect the heart. In the latter case, the removal of the myxoma first disclosed a significant mitral lesion which had been masked by the huge myxoma. All patients but one, who died of pneumonia, showed a good recovery. In this series, the problems of surgical treatment for cardiac myxoma and associated lesions are also discussed.     

Left atrial myxoma and systemic AL-amyloidosis.

A case of left atrial myxoma with systemic AL-amyloidosis is described. Localized myxomas have the peculiar property of giving rise to constitutional symptoms, indicating a systemic disease process. The coexistence of AL-amyloidosis and an atrial myxoma in the same patient makes it tempting to suggest that an immunological defect is involved in the development of both diseases.     

19例心房粘液瘤的免疫组化研究

为阐明CMS的组织起源,本文对19例CMS作了免疫组化研究。结果表明,全部病例的肿瘤血管及肿瘤间质细胞对Vimentin显阳性反应;成熟血管内皮细胞对UEA显阳性反应;部分粘液瘤的间质细胞与血管平滑肌细胞对Desmin和Myosin显阳性或弱阳性反应;少数病例的部分瘤细胞对S-100蛋白显弱阳性或阳性反应;全部CMS的上皮性标记物AE_1和AE_3均为阴性。研究表明,CMS具有多种间充质细胞成分,它们均可能同源于多潜能原始间叶组织。瘤细胞对免疫组化反应的差异,反映了肿瘤组织的分化和成熟程度可能有差异。文中对CMS的病理组织学和组织化学也作了观察和分析。     

Odontogenic tumors in Chile: a study of 362 cases.

BACKGROUND: Odontogenic tumors are infrequent lesions. Thus, the review of a large number of cases becomes a necessity for both the pathologist and the clinician. Studies on odontogenic tumors have been published in many parts of the world, but there is little information available in the English language literature on the relative frequency of odontogenic tumors in Latin America. The aim of this study was to determine the relative frequency of this heterogeneous group of lesions in a Chilean population, and to compare these data with previous reports. METHODS: We reviewed the records of 28,041 specimens from 1975 to 2000 in the Oral Pathology Referral Institute (IREPO), and using the criteria for histological typification published by the World Health Organization in 1992, we reclassified the odontogenic tumors. RESULTS: We confirmed a total of 362 odontogenic tumors. The frequency of odontogenic tumors as a percentage of all pathological specimens in our institute was 1.29%. The most frequent histological type was odontomas (44.7%), followed by ameloblastomas (20.4%) and myxomas (8.8%). CONCLUSIONS: Odontogenic tumors are uncommon lesions in the Chilean population and malignant odontogenic tumors are very rare. The relative frequency of various types of odontogenic tumors, as well as the age and gender distribution are similar to those reported in the North American series and different from those found in recently published Asian and African series.     

Diagnosing intramuscular myxoma by fine-needle aspiration: A multidisciplinary approach

The gross and microscopic appearances of aspirates from ten intramuscular myxomas are reported. The specimens were obtained from seven women and three men, ages 43 to 75, who had tumors involving the muscles of the thigh (7), upper arm (2), and forearm (1). Magnetic resonance (MR) imaging performed in six of the ten cases revealed well-defined, sharply demarcated tumors exhibiting low signal intensity relative to muscle on the T1-weighted images. The tumors were hyperintense to muscle on T2-weighted images. All aspirated tissues were clear, tenacious, and viscous. Smears contained few spindled and histiocytoid cells in an abundant mucoid background. Spindle cells demonstrated long cytoplasmic processes that in areas intertwined to form fibrillar tangles. Nuclei were oval to spindled with fine chromatin and inconspicuous nucleoli. Capillaries were sparse with simple (nonplexiform) branching. The differential diagnosis of myxoid lesions of the extremities includes benign entities such as myxoid schwannoma and neurofibroma, mesenchymal repair, and ganglion cyst, as well as malignant neoplasms such as myxoid liposarcoma, fibrosarcoma, malignant fibrous histiocytoma, and extraskeletal chondrosarcoma. The findings of this study revealed that, although the cytologic features were suggestive of intramuscular myxoma, a definitive diagnosis was often difficult, owing to scant cellularity and lack of distinctive cytologic features. The MR imaging findings may be utilized as an adjunct to the cytologic features to more confidently suggest a diagnosis of intramuscular myxoma. Diagn Cytopathol 1994;11:255–261. © 1994 Wiley-Liss, Inc.     

Right atrial myxoma mistaken for recurrent pulmonary thromboembolism

A 69 year old man was admitted for investigation of right sided pleuritic chest pain and dyspnoea, both of which began suddenly four days before admission. Acute pulmonary embolism was diagnosed. Six months after discharge while on warfarin he died. Necropsy found a 50 mm diameter myxoid tumour arising on the right atrial side of the interatrial septum. This lesion may have been discovered earlier by echocardiography although there were no clear indications for this investigation. Presentation was that of recurrent pulmonary embolism with no obvious source or cause of thrombosis. Patients who are thought to have idiopathic pulmonary embolism should undergo early echocardiography to exclude the rare but treatable diseases of the right heart that may be responsible

Keywords: atrial myxoma     

Anticoagulation therapy for pulmonary embolism involving a myxoma mimicking,giant type C thrombus: A case report

Right heart thrombus (RHTh) with concurrent acute pulmonary embolism (PE) is rare and can seriously destabilize hemodynamics, leading to an emergency situation with high mortality. Diagnosis and treatment of RHTh with acute PE are not yet standardized. There are few reports of acute PE concurrent with RHTh and even less is known about patients with a right heart mural thrombus. For physicians, the diagnostic choice and treatment of these patients are particularly difficult due to the lack of knowledge. Here, we report a rare case of partial mural RHTh (type C RHTh) with acute PE. The mural mass in the right heart was initially diagnosed as atrial myxoma according to transthoracic echocardiography (TTE), and both pulmonary embolus and the mural mass were completely absorbed after administering Rivaroxiban. This case suggests that TTE alone is insufficient to identify and diagnoses a right heart mural mass such as this. However, novel oral anticoagulants may be effective at alleviating PE with type C RHTh.     

Cardiac Myxoma: Histochemical and Ultrastructural Localization of Glycosaminoglycans and Proteoglycans

A recurrent cardiac myxoma is examined histochemical ly at the ultrastructural level. By routine electron microscopy the stellate “myxoma” cell exhibits features suggestive of a secretory function in synthesis of its myxoid stroma. Spicer's high iron diamine (HID), which stains specifically for sulfated glycoconjugates, is utilized for intracellular localization of glycosaminoglycans. HID-positive reactive sites are localized within the Golgi-derived vacuoles and secretory granules of the myxoma cells. No staining is obtained with other cytoplasmic organelles except rare secondary lyso-somes. Although colloidal iron is less specific, both intracellular and extracellular positive reactive sites are observed. With ruthenium red staining the proteoglycans in the extracellular stroma can be visualized as numerous positively stained, polygonal 250-500 A matrix granules with faint filamentous projections. Positive intracellular ruthenium red-stained granules are also observed within the Golgi-derived vacuoles. The alcianophilia of the myxoid stroma with Alcian blue is almost completely abolished by prior treatment with bovine testicular hyaluronidase but is unaffected by leech hyaluronidase, indicating chondroitin sulfates A and/or C, not hyaluronic acid, as the major biochemical constituents of the stroma and the observed extracellular matrix granules. The above findings provide cytochemical evidence of intracellular synthesis of sulfated glycosaminoglycans and proteoglycans of the myxoma cell and its active participation in production of its stroma.