Necrotizing sialometaplasia of the parotid gland associated with angiocentric T-cell lymphoma: a case report and review of the literature.

A very rare case of necrotizing sialometaplasia of the parotid gland associated with angiocentric T-cell lymphoma was described. A 66-year-old male had left neck and pharyngeal masses and biopsy specimen showed a monotonous proliferation of atypical lymphoid cells with massive necrosis in the parotid gland. Angiocentric pattern or vascular invasion by the lymphoid cells was observed and the involved parotid gland exhibited squamous metaplasia of the ducts and acini; necrotizing sialometaplasia. Immunohistochemical analysis revealed a cytotoxic T-cell phenotype of the lymphoid cells (CD3+, CD4-, CD5+, CD8+, CD56-, Granzyme B+, TIA-1+, Perforin-) but in situ hybridization showed no relation to Epstein-Barr virus. Although necrotizing sialometaplasia is relatively rare in the parotid gland, angiocentric T-cell lymphoma should be considered for a causative condition of necrotizing sialometaplasia.