Necrotizing sialometaplasia versus invasive carcinoma of the head and neck: the use of myoepithelial markers and keratin subtypes as an adjunct to diagnosis

Abstract

Identification of myoepithelial cells and CK7 expression may help to distinguish NSM from its mimics.

Case report of necrotizing sialometaplasia

“…The differential diagnosis of necrotizing sialometaplasia should consider other ulcerous and erosive lesions, including those of traumatic or inflammatory/infectious aetiology, e.g., dental fissures, major aphthae, tuberculosis, tertiary syphilis or deep fungal infection in patients with AIDS or under immunosuppressive treatment (6,8,11), and those of cancerous origin, e.g., squamous cell carcinoma, mucoepidermoid carcinoma, adenoid carcinoma, leukaemia, non-Hodgkin lymphoma or sarcoma (6,8,13,14). NS is differentiated from tuberculosis, syphilis and fungal ulcers by means of serologic tests and by staining histopathological samples for fungi, bacilli and bacteria (6).…”

“…NS is differentiated from tuberculosis, syphilis and fungal ulcers by means of serologic tests and by staining histopathological samples for fungi, bacilli and bacteria (6). Histological criteria to distinguish NS from a malignancy are: (1) preserved general lobular morphology, (2) bland appearance of squamous islands or nests with no cytological evidence of malignancy and (3) no findings of residual ductal lumina in any nest (4,14). Reactive atypias are occasionally observed in nests or islets, and the diagnosis must then be confirmed by the general lobular appearance and the presence of intraepithelial inflammation in squamous nests (4).…”

“…Reactive atypias are occasionally observed in nests or islets, and the diagnosis must then be confirmed by the general lobular appearance and the presence of intraepithelial inflammation in squamous nests (4). When samples are too small to permit study of the general architecture, this entity can be confused with a squamous cell or mucoepidermoid carcinoma (10,14). In addition, the metaplastic and hyperplastic changes can be florid, and the reparative fibrosis can be confused with infiltrate (10).…”

Necrotizing sialometaplasia after lower lip wedge resection

“…If atypia is alarming with single cell necrosis, application of immunhistochemistry panel including myoepithelial markers (smooth muscle antibody, p63, calponin), basement membrane markers (laminin, collagen type IV), E-cadherin and various cytokeratins (CK 5, CK 6, CK 7, CAM 5.2) has been suggested. Histologically, maintenance of lobular architecture is the best clue for NS [4,6].…”

Reactive, Infectious and Benign Lesions of Salivary Gland- A Review

“…(Ki-67) and the presence of 4A4/p63-and calponin-positive myoepithelial cells. [19] Healing takes place over several weeks by secondary intention. Patient reassurance, wound irrigation using a bland baking soda-and-water mouth rinse, and occasional use of analgesics are the only management steps necessary.…”