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Updated: Feb 4, 2026

Generation of Lymph Node-fat Pad Chimeras for the Study of Lymph Node Stromal Cell Origin
Published on: December 16, 2013
Metastatic squamous cell cancer with unknown primary origin in the mediastinal lymph node
1Department of Pulmonology, University of Health Sciences Istanbul Sureyyapasa Chest Diseases and Thoracic Surgery Training and Research Hospital, Istanbul, Turkey.
Abstract:
Metastatic tumors with unknown primary origin are a group of heterogeneous tumors with undetectable primary tumor site on admission. They have the common properties of rapid and aggressive progression and unpredictable metastases. They form 3%-5% of all cases with cancer and the fourth-most common cause of cancer-related deaths. The histological type of these tumors is commonly (90%) adenocarcinoma, whereas 5% are squamous cell carcinomas. Metastasis is observed in the liver, lungs, and bones. Mediastinal lymph node metastasis is extremely rare. They have a poor prognosis and the mean survival is shorter than a year. The case we have presented is a rare case due to its mediastinal lymph node involvement among tumors with unknown origin and squamous cell histological subtype.
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