3. Discussion
In this case, the patient did not present with symptoms at the first visit. The symptoms of PCA are usually nonspecific and include chest pain, shortness of breath, malaise, and fever1. Pericardial effusion is also common in patients with PCA; however, in general, the detection of angiosarcoma cells is difficult even with a cytological evaluation of the pericardial fluid7, as seen in our patient. Hence, when one encounters a patient with unexplained pericardial effusion, the possibility of malignancies including PCA should not be excluded, even with a “negative” result of the pericardial effusion cytology.
Given the low frequency of PCA and a relatively higher incidence of metastatic cardiac tumor, diagnosis of cardiac angiosarcoma as the primary lesion is sometimes challenging. In the current case, we encountered this difficulty as the patient had multiple tumor nodules in the liver, spleen, and skin. Besides the heart, angiosarcomas can arise in the soft tissue, breast, liver, bone, spleen, or other visceral organs8. Furthermore, the incidence of angiosarcoma in the cutaneous soft tissue, liver, or spleen is higher than that in the heart8. In this regard, Cunha-Silva et. al.suggested the following factors to evaluate whether the cardiac angiosarcoma is primary or not9: (1) patient’s age and lifestyle history, (2) number of lesions (i.e., single or multiple) in the heart, and (3) location of the lesion in the heart. In addition, while cardiac metastasis of liver angiosarcoma is rare, the liver is a common metastatic site of PCA9. In the current case, the patient had no history of exposure to thorium oxide, vinyl chloride, arsenic, or anabolic steroids, all of which are risk factors for hepatic angiosarcoma. Moreover, the cardiac lesion was single, and the hepatic lesions were multiple. The cardiac lesion located in the right atrium, the most common site for PCA. These findings strongly suggest that the cardiac angiosarcoma in this case was PCA.
Pericardial extension of the tumor was observed in 71% of 17 cases of PCA7, and cardiac rupture due to PCA has also been reported10. However, to the best of our knowledge, a case of PCA with direct lung invasion has not been described previously. In the current case, the tumor penetrated the pericardium and invaded the lung. However, neither fatal cardiac tamponade nor rupture occurred in this case. Although the incidence of lung invasion may be low, it may be meaningful for the clinical management of PCA to recognize the possibility of lung invasion.
In conclusion, we presented an autopsy case of PCA that directly invaded the right lung. Although PCA is an extremely rare disease, it should be included in the differential diagnosis of a cardiac mass with pericardial effusion.