Spontaneous regression of primary mediastinal germ cell tumor

Primary germ cell tumours of the mediastinum: A review with emphasis on diagnostic challenges

This article will review current aspects of the histopathological, immunohistochemical and molecular analysis of primary mediastinal germ cell tumours (PMGCTs) as well as their aetiological, epidemiological, clinical and therapeutic features. PMGCTs represent an important differential diagnosis in the spectrum of mediastinal tumours, and their diagnosis is usually made on small tissue samples from core needle biopsies in combination with diagnostic imaging and serum tumour markers. As in lymphomas, a small biopsy is often the only viable tumour sample available from these patients, as they receive chemotherapy prior to eventual surgical resection. Pathologists therefore need to apply an efficient combination of immunohistochemical markers to confirm the diagnosis of a PMGCT and to exclude morphological mimics.

Spontaneous regression of anterior mediastinal seminoma with normalization of β-human chorionic gonadotropin levels

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Spontaneous regression of anterior mediastinal seminoma with normalization of β-human chorionic gonadotropin (β-hCG) levels shows good clinical outcome and sensitive to chemotherapy.

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Video-assisted thoracic surgery (VATS) is effective solution for definite diagnosis of anterior mediastinal.

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Apoptosis may be a reason of tumors’ spontaneous regression.

Introduction

Although spontaneous regression (SR) of anterior mediastinal seminoma is very rare with normalization of β-human chorionic gonadotropin (β-hCG) level, video-assisted thoracic surgery (VATS) is the most effective solution for definite diagnosis of indeterminate anterior mediastinal masses.

Diagnosis, therapeutic interventions, and outcomes

A rare case of an asymptomatic 37-year-old man with an anterior mediastinal mass that was detected on a routine chest X-ray is presented. Computed tomography (CT) showed a large anterior mediastinal tumor with superior vena cava invasion and SR before VATS for definitive diagnosis. On pathology, the definitive diagnosis was seminoma. Microscopic examination showed abundant apoptotic cells within the tumor. Chemotherapy (bleomycin 30 mg/day, etoposide 200 mg/day, cisplatin 40 mg/day) was given to this patient, and the tumor showed high sensitivity.

Conclusion

Anterior mediastinal seminoma showing SR induced by spontaneous apoptosis of tumor cells may have good sensitivity to chemotherapy, and a good clinical outcome may be achieved in these patients. This case also highlights that VATS is the most effective solution for definite diagnosis of indeterminate anterior mediastinal masses.

Spontaneous regression of thymic epithelial tumours

We herein report the cases of 3 patients with thymic epithelial tumours, including two thymomas and a carcinoma, where the tumours spontaneously regressed in size. The patients were all female ranging in age from 32 to 43 years. During 1 or 2 months without any treatment, the tumours regressed by 25-59% in size. The pleural effusion observed in 2 patients also disappeared during the same period. Pathological examinations revealed areas of necrosis or cystic changes within the two thymomas. Among the patients with thymic epithelial tumours, the existence of this rare disease entity must be recognized.

[Cardiac tumors. Experience with two cases]

Cardiac tumors are rare neoplasms with an incidence of 0.027 cases per 100. Up to 90 % of these tumors are benign but, because of their location, they can be lethal, despite their histology. Most appear in infants aged less than 1 year. Teratomas, which are relatively frequent in the pediatric age group, are usually located in the ovaries, sacrococcygeal area, thorax, and retroperitoneal area. Intrapericardial location is less frequent. In this localization, the clinical manifestation depends on compression of adjacent structures and determines the therapeutic attitude in each case. Imaging studies should be performed and the definitive diagnosis is obtained after surgical resection, which is the treatment of choice. The differential diagnosis should include other tumors of the anterior mediastinum, thymus hypertrophy, pericardial effusion and primary cardiac disorders such as pericardial mesothelioma, Ebstein malformation, and intrapericardial bronchogenic cysts. We present two patients who were diagnosed in the first year of life in our hospital. Both children developed pericardial tumours. In one patient, the mass decreased and disappeared while in the other, who received a later diagnosis, surgical treatment was required.

[Cardiac changes in mediastinal seminoma]

Primary pure cell seminoma of the mediastinum is a rare and potentially fatal lesion. Encroachment or invasion of adjacent structures is common, as are distant metastases. We present an unusual case of mediastinal seminoma with directly intracavitary invasion into the right atrium and extension to the left atrium. A 22-year-old male with right side chest pain, progressive cough, dyspnea, fever and right arm swelling lasting about a month is presented. Chest radiography on admission revealed a large mass in the anterior mediastinum. A cardiac ultrasonographic examination showed right atrial compression by the mass, with invasion of the right atrium wall. We also found polyp-like (about 2.5 cm in diameter) masses in left atrium near the area of the right pulmonary veins and a circumferential pericardial effusion. Percutaneous needle biopsy revealed mediastinal seminoma. To our knowledge, no similar case has been previously reported.