Tracheal carcinoma ex-pleomorphic adenoma

Enhancing mid-upper tracheal lesion almost obliterating the airway

Enhancing mid-upper tracheal lesion almost obliterating the airway

The lesion in the mid-upper trachea demonstrates focal increased FDG uptake at PET/CT

After tracheal excision. The lesion appears somewhat smaller than on CT because there had been a previous biopsy

MACROSCOPIC DESCRIPTION:  
A segment of trachea 25 mm diameter and 27 mm long. The superior edge is marked with a suture. Superior inked blue, inferior black. Occupying approximately 20% of the circumference of the trachea is a predominantly submucosal nodule 13 x 14 x 6 mm. The nodule has a uniform slightly glistening pale tan cut surface and compresses underlying tissue with a broad front. In one area it seems that the lesion might extend between rings of cartilage.

MICROSCOPIC DESCRIPTION: 
Sections of the trachea show a cellular malignant epithelial tumor. The epithelial cells form large nodules, cribriform structures, smaller nests, trabeculae and cords. The epithelial cells have enlarged, angulated and hyperchromatic nuclei, small nucleoli and scanty cytoplasm. There are also myoepithelial cells lining the tumor nests. The background contains basement membrane material and hyaline globules. The ductal lumina contain basophilic mucoid material. Scattered mitoses are noted. No evidence of lymphovascular or perineural invasion is seen. The tumor extends full thickness into the wall, through the cartilage and involving the deep posterior soft tissue margin. The superior and inferior margins are clear by at least 5mm. The features are those of adenoid cystic carcinoma. 

DIAGNOSIS: 
Trachea: Residual adenoid cystic carcinoma.
- 14 mm in size
- No evidence of lymphovascular or perineural invasion
- Tumor invades through the cartilage into the deep posterior soft tissue margin
- Superior and inferior margins clear by at least 5 mm