Gingival squamous cell carcinoma masquerading as necrotizing ulcerative periodontitis

Abstract

Necrotizing ulcerative periodontitis (NUP) is a painful and debilitating condition seen mostly in an immunocompromised state. Although squamous cell carcinoma (SCC) on gingiva is not uncommon, its presentation as a benign necrotizing lesion on gingiva is rare. Such presentations may lead to delayed diagnosis and poor prognosis. This report describes a case of a 34-year-old male presenting clinically with NUP around mandibular posterior teeth. Clinical features were misleading, but the histological findings established the diagnosis of well-differentiated SCC. Immunohistochemistry also showed features of epithelial-mesenchymal transition with decreased expression of E-cadherin and increased vimentin expression showing local invasion and metastasis. The patient was referred to the oncology department for evaluation of possible metastasis and further management of carcinoma.

Keywords: Gingiva; immunohistochemistry; periodontal disease; squamous cell carcinoma.

Figure 1

Clinical picture showing severely inflamed gingiva with necrosis of interdental papilla between right second mandibular premolar and first molar. The lesion can be seen extending from the mesiobuccal aspect of the first premolar to the distal aspect of the first molar

Figure 2

Periapical radiograph of the involved region showing severe loss of alveolar bone around #45 and #46

Figure 3

Well-differentiated squamous cell carcinoma: Tissue section showed clusters of atypical large polygonal tumor cells with a hyperchromatic nucleus, prominent nucleoli, irregular nuclear membranes, and well-defined eosinophilic cytoplasm, with keratin pearl formation. H and E, ×40

Figure 4

The decreased intensity of membranous staining in tumor cells (1+). Immunohistochemistry E-cadherin, ×40

Figure 5

Mild focal cytoplasmic positivity in tumor cells (1+). Immunohistochemistry Vimentin, ×40