Introduction: Rare primary thoracic tumors are defined as tumors of unusual histopathology developped in the thorax. They represent less than 1% of primary lung tumors.

Materials and Methods: Study during 5 years (2015-2020) including patients with thoracic mass.

Results: Twenty patients (12 men and 8 women). Diagnostic means were per-endoscopic in 6 cases, the scano-guided needle biopsy in 10 cases, and surgical in 4 cases. Histological types were: carcinoid tumor (n=6), large cell sarcomatoid carcinoma (n=1), pleomorphic carcinoma (n=2), pulmonary blastoma (n=3), basaloid carcinoma (n=1), primary lymphoma of the lung (n=1),  thymic carcinoma with angiomatoid component (n = 1), pulmonary artery sarcoma (n=2),primary pulmonary sarcoma (n=1), Giant cell bone tumor  (n=1) and Schwannoma (n=1).

Conclusion: The control of the progression of a tumor is based on a reasoned diagnostic approach and the early implementation of an appropriate treatment. The progress made in medical imaging, associated with the work of clinicians and pathologists, now allows increasingly early diagnosis for better management of rare intrathoracic tumors.