About a lymphoepithelioma-like carcinoma of the lung with an endotracheal localization.

INTRODUCTION: Lympho-epithelioma like carcinoma is a rare lung tumour that acounts for less than 1% of non small cell lung carcinomas. It is defined as a special entity among the 2015 World Health Organization.

AIM: Our aim was to describe a completely illustrated new case of lymhpo-epithelioma like carcinoma. We describe a new case diagnosed in our Department of Pathology.

CASE PRESENTATION: The authors describe a case of a 22-year-old woman without a particular past medical history who presented non specific respiratory symptoms. Radiologic investigations revealed a tracheal tumor with enlarged mediastinal lumph nodes. A first biopsy was performed revealing a malignant tumor with a squamous differentiation highlighted by immunohischemistry. A surgical biopsy was performed and the final microscopic diagnosis revealed a lymphoepithelioma-like carcinoma of the lung. This diagnosis was retained after ruling out a possible metastasis of a nasopharyngeal carcinoma whose microscopic features are similar to this subtype of lung tumor.

CONCLUSION: This case points out the rarity of this diagnosis, especially in a young and caucasian patient and highlights the diagnostic dilemma caused by this kind of tumor.