In several editions of Physical Diagnosis, concerning<unk>  the author writes: :According to Christian1 the<unk>  neoplasms which are neither so rare nor so obscure as to make diagnosis practically impossible are: (1) Sarcoma (including lymphosarcoma, leucaemic growths, and Hodgkins' disease; (2) Teratoma and cyst. Many signs and symptoms of a<unk> do not distinguish between these two principal classes of<unk>  However, on a radiograph usually the former class will have an irregular shape and the latter class will have a smooth spherical or ovoid shape. A large minority of patients with a<unk>  teratoma (including dermoid cyst) will cough up hair. For a differential diagnosis, the key is to exclude aneurism.
Mediastinal tumors
Tracheal tumor
Lung tumor
Airway obstruction
Lung nodule
Mediastinitis
Pleural disease
Lung cancer