Primary seminoma arising in the middle mediastinum: A case report.

Primary mediastinal seminoma often occurs in the anterior mediastinum of young males. It is unusual for the tumor to originate in the middle or posterior mediastinum, and such cases have rarely been reported in the English literature. The present study reports the case of a 52-year-old man with a 3.0-cm primary seminoma arising in the middle mediastinum. The patient presented with the symptoms of cough and chest tightness. Fluorine-18 fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) scans revealed unique abnormal FDG uptake in the middle mediastinum. A mediastinoscopy was performed and integral excision was found to be difficult. A biopsy was performed and the histological examination revealed a primary seminoma. Following 4 cycles of a standard bleomycin, etoposide and cisplatin chemotherapy regimen, and chest irradiation at a total dose of 40 Gy in 20 fractions, the tumor exhibited a partial response, decreasing in size, and FDG uptake was no longer observed on 18F-FDG-PET scan. The last follow-up date was April 2016 and the patient has remained disease-free for 20 months.