A rare case of life-threatening mixed germ cell tumor infiltrating the heart: A case report.

INTRODUCTION AND IMPORTANCE: Extragonadal germ cell tumors at the mediastinum are rare and comprise of 3-4 % of all germ cell tumors. Mixed GCTs can remain asymptomatic for long periods and often present with complications. We present a case of a young male patient with a mediastinal tumor infiltrating the heart and obstructing the right ventricular outflow tract, causing cardiogenic shock.

CASE PRESENTATION: A 16-year-old male came with chief complain of shortness of breath and underwent an echocardiogram which revealed a mass in the right atrium and right ventricle. On CT scan, a solid mass in the mediastinum, expanding and infiltrating the right atrium was found. Our patient underwent surgical treatment. Histopathology results were consistent with mixed germ cell tumor comprised of seminoma, yolk sac, and mature teratoma at the right atrial and mediastinum.

CLINICAL DISCUSSION: The pathogenesis of extragonadal GCTs has been linked to abnormal and/or incomplete migration of the primordial germ cells from the endoderm yolk sac to gonads. Mediastinum GCT can become clinically problematic through its growth patterns, especially its expansive profile, which can cause compression on surrounding mediastinal structures, including major vessels, which in turn diminish blood flow. Overall survival improvement is strongly linked with surgical resection of the tumor, which achieve removal of tumor tissue resistant to chemotherapy and provides sample for histological examination, which helps assessment of pathological response to chemotherapy and planning of further management.

CONCLUSION: The mediastinum is a site of different neoplasia, including germ cell tumors. Despite its low incidence, the diagnosis of a mediastinal mixed germ cell tumor should be considered in young patients with a mediastinal mass. This tumor is aggressive and often infiltrates surrounding structures and metastasis. Physicians must be aware of the difficulties and complications associated with the diagnosis.