Abstract

Bronchogenic cyst is an uncommon congenital anomaly that arises from maldevelopment of the primitive foregut, and is usually found in the lung and mediastinum. Cutaneous or subcutaneous bronchogenic cysts are rare, and occur especially in the shoulder region. We report here on a 40-year-old woman with a soft, nontender, cystic mass on the upper posterior aspect of the right acromioclavicular joint; this had been recognized about 20 years before. She underwent incision and drainage of the lesion at a local clinic about 1 year ago, but the wound was not healed. MRI showed an irregular-shaped dark signal intensity lesion that measured 2 x 1.5 cm in the subcutaneous fat layer. Microscopically, the cyst was lined by pseudostratified ciliated columnar epithelium that displayed squamous metaplasia. The cyst wall revealed frequent smooth muscle bundles, occasional seromucous glands and multifocal lymphocytic infiltration. This is the first reported case of subcutaneous bronchogenic cyst of the shoulder in a Korean adult.

• Keywords: Bronchogenic cyst;Adipose tissue;Shoulder