Clinicopathological analysis of small-sized anterior mediastinal tumors.

Purpose: The purpose of this study was to determine the clinicopathological findings and prognosis of small-sized anterior mediastinal tumors (SSAMTs).

Methods: A retrospective study was conducted on 43 patients who underwent surgery between January 1989 and December 2011 for SSAMTs.

Results: From the preoperative radiological findings, the tumors were classified into solid (n = 28) and cystic lesions (n = 15). The pathological diagnoses of the solid lesions included thymoma (n = 24), thymic carcinoma (n = 1), mucosa-associated lymphoid tissue lymphoma (n = 1), teratoma (n = 1) and neurofibroma (n = 1), and those of the cystic lesions included thymic cysts (n = 8), thymoma (n = 3), bronchogenic cysts (n = 2), teratoma, (n = 1) and a pericardial cyst (n = 1). The 27 thymomas were composed of stages I (n = 22), II (n = 3), III (n = 1) and IVb (n = 1). The overall survival in the 43 patients was 97.1 % at 5 years. In the 28 patients with solid lesions, the overall survival was 95.8 % at 5 years. All patients with cystic lesions were still alive at the last follow-up.

Conclusion: Cystic lesions of SSAMTs were benign lesions or stage I thymoma, and most of the solid lesions of SSAMTs were stage I or II thymomas. SSAMTs are good candidates for video-assisted thoracic surgery procedures, as conversion to sternotomy can be selected based on the intraoperative findings of pericardial invasion and a rapid pathological diagnosis of thymic carcinoma.