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we report a patient with cardiac tamponade due to pericardial metastasis and pericardial effusion , originating from gastric signet - ring cell carcinoma , a rare condition with few reports , mostly case reports , in the literature .
it is usually detected during the terminal stages of gastric carcinoma , and therefore , the prognosis is poor .
signet - ring cell cancer with pericardial involvement was diagnosed by pericardial biopsy following subxiphoid pericardiostomy [ 1 , 2 ] . here , we discuss the importance of pericardial biopsy as primary focus of malignancy and the proceeding treatment .
an 85-year - old man was admitted with anorexia and general malaise on august 5 , 2014 . he reported a weight loss of 4 kg in the previous month .
he had been operated by the billroth i procedure when diagnosed with gastric ulcer at the age of 41 years .
physical examination revealed that he was febrile , with a heart rate of 118 bpm and a blood pressure of 117/95 mm hg .
chest x - ray revealed an increased cardiothoracic ratio and a small amount of left pleural effusion .
electrocardiography showed low voltage , and 2-dimensional ultrasonographic echocardiography revealed pericardial effusions with atrial and right ventricular early diastolic collapse , establishing the diagnosis of cardiac tamponade ( fig .
laboratory studies showed a serum albumin level of 3 g / dl , a serum creatinine level of 1.70 mg / dl ( reference value : 0.40.9 mg / dl ) and a brain natriuretic peptide level of 71.7 pg / ml ( reference value : 018.4 pg / ml ) .
the signet - ring cell carcinoma of the operated stomach was revealed by gastric fiberscope examination ( fig .
, we found elevations of carcinoembryonic antigen ( cea ) and carbohydrate antigen ( ca ) 19 - 9 at 27.9 ng / ml and 8,424 u / ml , respectively .
we diagnosed the patient with gastric cancer stage iv and suggested him the best supportive therapy .
he died of cardiac arrest 1 month after best supportive care without severe cancer pain .
written informed consent was obtained from the patient 's family for publication of this case report and any accompanying images .
pericardial biopsy is a unique diagnostic and therapeutic approach that reveals malignant and infective disorders .
interestingly , the histology of the 42 patients who were classified later by a combination of cytology and histology as being affected by a malignant effusion was diagnostic only in 10 patients ( 24% ) . the larger contribution to the diagnosis was given in 37 of the 42 patients ( 88% ) by cytology .
pericardioscopy allows direct visualization of the pericardial space ; the reported sensitivity for the diagnosis of malignancy is as high as 97% .
in contrast , the sensitivity for blind pericardial biopsy is lower , presumably because of sampling error .
the therapeutic drainage created by a subxiphoid or transthoracic approach yields a 4-cm piece of tissue , which can be useful to confirm the diagnosis .
we performed a visualized subxiphoid approach and reached the definite diagnosis of rare gastric cancer metastasizing to pericardium .
abrams et al .   reported metastases of 119 consecutive autopsied cases of stomach carcinoma .
the incidence rates of primary gastric carcinoma metastasized to different organs were only 4.2% for the pericardium and 2.5% for the heart .
autopsy investigations of the stomach showed a pericardial metastasis incidence rate of 4.37.7% [ 4 , 5 , 6 , 7 ] .
a search of the medline database revealed 6 cases of signet - ring cell gastric carcinoma presenting as cardiac tamponade [ 8 , 9 , 10 , 11 , 12 ] .
we found late - stage primary gastric signet - ring cell carcinoma from surgical biopsy , despite the fact that there were gastrointestinal symptoms and signs such as anorexia , abdominal pain and weight loss .
the patient died without severe pain 1 month after best supportive therapy . since his symptoms of cardiac tamponade were more obvious than his gastrointestinal symptoms , we focused on heart examination and did not do tests such as an endoscopic examination of the stomach of the patient at first .
moreover , due to the rapid progression of the disease , serum levels of tumor markers , including cea and ca 19 - 9 , would have shown the patient 's malignancy .
the diagnosis of pericardial disease in patients with cancer is often extremely difficult because patients present with nonspecific symptoms and physical findings .
therefore , clinicians must consider pericardial disease in any patient with a known malignancy who develops unexplained dyspnea , tachycardia , arrhythmia or symptoms of heart failure .
this shows that primary gastric carcinomas presenting as cardiac tamponade are rare , and medical practitioners should be aware of malignancy of the stomach when patients present with unexplained cardiac manifestations .
we conclude that pericardial biopsy is a useful tool for the causal diagnosis of cardiac tamponade from primary gastric cancer .
we describe the case of an 85-year - old man who presented with a large pericardial effusion . the patient was admitted because of anorexia and general malaise . 
 chest x - ray revealed an increased cardiothoracic ratio and a small amount of bilateral pleural effusion . 
 two - dimensional ultrasonographic echocardiography showed pericardial effusions with atrial and right ventricular early diastolic collapse , establishing the diagnosis of cardiac tamponade . 
 signet - ring cell cancer with pericardial involvement was diagnosed by subxiphoid pericardiostomy . 
 the clear fluid was removed through pericardial drainage . 
 the signet - ring cell carcinoma of the stomach was revealed by gastric fiberscope examination after pericardial biopsy proved malignancy . 
 virchow lymph node metastasis was also found . 
 we diagnosed the patient with gastric cancer stage iv and suggested him the best supportive therapy . 
 he died of cardiac arrest 1 month after best supportive care .