Case report of polymorphous low-grade adenocarcinoma in the trachea with metastasis to the right middle lobe bronchus.

Polymorphous low-grade adenocarcinoma (PLGA) is a low-grade malignant infiltrative tumor of the minor salivary glands. According to data from PubMed (National Center for Biotechnology), one case of PLGA involving the left main bronchus and one case involving the right main and upper lobar bronchi have previously been reported. Here, we describe the first case of PLGA originating in the trachea with metastasis to the right middle lobe bronchus, all initially misdiagnosed as adenoid cystic carcinoma (ACC). It is particularly important to distinguish this tumor from other types of salivary gland tumors, especially ACC. Complete surgical excision is the curative treatment of choice for PLGA.