Benign schwannoma of posterior mediastinum accompanied by bloody pleural effusion misdiagnosed as solitary fibrous tumor: A case report

Background: Schwannoma is a peripheral nerve sheath tumor originating from schwann cells. It is the most common neurogenic tumor of the posterior mediastinum. Pleural effusion is a rare presentation of benign schwannoma and it is mainly related to malignant tumors. Histologically, schwannoma as well as solitary fibrous tumor should be considered as a differential diagnosis of spindle cell lesions. Case presentation: Here, we report a case of an asymptomatic 61-year-old female misdiagnosed as solitary fibrous tumor of posterior mediastinum which was revealed to have blood stained pleural effusion during the video-assisted thoracic surgery. Eventually pathological study and immunohistochemistry profile of the tumor was reported as benign schwannoma. Conclusion: This report indicates that benign schwannoma can be accompanied by bloody pleural effusion and it also emphasizes the role of immunohistochemistry in the diagnosis of biopsy specimen of spindle cell lesions.