Long-term survival after resection of mediastinal lymph node with metastasis of giant cell carcinoma from an unknown primary site; a case report

Abstract

Our patient, a 41-year-old male, is alive without any signs of tumor 3 years and 11 months after extirpation of a mediastinal lymph node with metastasis of giant cell carcinoma from an unknown primary site. Most cancers of unknown primary origin discovered in metastatic lymph nodes are found in cervical lymph node metastases, not mediastinal ones. In general, the prognosis of cancer of unknown origin is extremely discouraging, and long-term survival is very rare. In our patient, the histology of the metastatic site was giant cell carcinoma and immunohistochemically other neoplasms, such an thymic carcinoma and malignant lymphoma, were denied. Therefore, the metastasis of lung cancer (T0N2M0) might cause the development of the mediastinal tumor, although the primary tumor has not yet been identified.