The differential for tracheal masses can be rather wide.
For a single mass consider:
- metastasis
- direct invasion from adjacent organ (lung, thyroid, esophagus and larynx)
- distant metastasis (e.g. melanoma, breast, renal, and colon cancer)
- primary neoplasms
- squamous cell carcinoma: commonest primary tracheal malignancy 2 (~50 %)
- adenoid cystic carcinoma (ACC): 2nd commonest primary tracheal malignancy: adenoid cystic carcinoma of tracheobronchial tree
- squamous cell papilloma
- adenocarcinoma
- bronchial carcinoid (if involves trachea)
- mucoepidermoid carcinoma
- chondrosarcoma
- tracheal leiomyosarcoma: rare
- tracheal leiomyoma
- endobronchial hamartoma (if involves trachea)
- tracheal lipoma 4: rare
- non-neoplastic lesions
For multiple masses consider:
- laryngotracheal papillomatosis
- tracheobronchial amyloidosis
- multifocal neoplasm