Synovial sarcoma of the pericardium

A precordial tumor of the pericardium was radiologically diagnosed as the c ause of an untypical clinical picture of heart disease in a 41-year-old sol dier. As the patient had an increased asbestos exposure due to his professi on, he war admitted to operation under the tentative diagnosis of a pericar dial mesothelioma and the question of an occupational disease (BK 4105). Mi croscopic and immunohistochemical findings are compatible with the diagnosi s of a synovial sarcoma of the pericardium. The present immunohistochemical marker spectrum allowed a reliable differentiation between synovial sarcom a and pericardial mesothelioma, which is more frequent than synovial sarcom a. The epitheloid component was determined using the following antibodies: MNF 116, CK 19, CK 7, EMA and Per EP-4 were positive while Faktor VIII,Calr etinin,S100,Vimentin,CEA, CD 31,bcl-2 and HBA-71 were negative. The sarcoma tous component was determined with antibodies to Vimentin, bcl-2 and HBA-71 which were positive, and to MNF 116, CK 19,CK 7, Faktor VIII,Calretinin, S 100, EMA, CEA, Ber EP-4 and CD 31 which were negative. Synovial sarcomas of the pericardium in the lower anterior mediastinum or the myocardium are ex ceedingly rare. A causal relationship between tumor formation and an increa sed asbestos exposure similar to the epidemiologically based experiences wi th pericardial mesothelioma - is not likely. Primary extrapericardial synov ial sarcoma could be excluded.