Necrotizing Sialometaplasia Workup

Updated: Mar 14, 2023
  • Author: John A Svirsky, DDS, MEd; Chief Editor: Jeff Burgess, DDS, MSD  more...
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Histologic Findings

The microscopic features of necrotizing sialometaplasia include coagulative necrosis of glandular acini and squamous metaplasia of its ducts. Mucin pooling is present, and an associated inflammatory infiltrate consists of macrophages; neutrophils; and, less commonly, lymphocytes, plasma cells, and eosinophils.

Pseudoepitheliomatous hyperplasia of the overlying mucosa can also be present, but the cytologic features of the squamous component are usually bland. Occasionally, isolated mucous cells may be entrapped within the squamous islands; these cells should not be confused with those of mucoepidermoid carcinoma.

The microscopic differential diagnosis for necrotizing sialometaplasia includes mucoepidermoid carcinoma and squamous cell carcinoma. Some believe that subacute necrotizing sialadenitis is yet another entity that occurs within the spectrum of necrotizing sialometaplasia; it should be distinguished from necrotizing sialometaplasia.