Abstract
A 58-year-old man was admitted with an abnormal shadow in the right cardiophrenic angle on a chest X-ray. Contrast-enhanced CT scan of the chest revealed a tumor shadow of about 2.5×3.0cm adjacent to the pericardium and diaphragm. Surgery was performed through a thoracotomy, under video-assisted thoracic surgery (VATS). The tumor was located in the junction between the diaphragm and pericardium, and protruded from the diaphragm into the chest cavity. The phrenic nerve was confirmed to run toward the tumor and be thickened in its vicinity. These findings suggested that the lesion was a neurogenic tumor originating in the phrenic nerve attached to the diaphragm. The tumor was extended to the diaphragm and histopathologically diagnosed as schwannoma. Total excision including the diaphragm should be performed. Schwannoma originating in the phrenic nerve is a rare disease, and only 21 cases, including our patient, have been reported so far in Japan. There is no report on schwannoma extending to the diaphragm and requiring excision together with a part of the diaphragm, as in our case, So it is considered to be an extremely rare case.
