[Basaloid squamous cell carcinoma in gingiva: a case report].

As an aggressive subtype of squamous cell carcinoma, basaloid squamous cell carcinoma (BSCC) rarely occurs in the oral and maxillofacial region. The gingiva is an unusual site of BSCC. This study reported a 78-year-old male who presented with left maxillary pain. Clinical examination revealed a gingival mass in the left maxilla. Under microscope, the lesion showed typical comedo necrosis and peripheral palisading. Areas of glandular-like structures were also observed. Immunohistochemistry results revealed that the Ki-67 score of BSCC in this case was 28%, and S-100 was positive in some areas. However, P16 and CK7 were negative. Finally, a diagnosis of BSCC was made based on the pathological and immunohistochemical characteristics. The patient underwent subtotal maxillectomy. After 12 months later, the patient was alive with no evidence of disease. Combined with relevant literature, this article analyzed the clinicopathological features, differential diagnosis, diagnosis, treatment, and prognosis of BSCC. Although surgery remains the main treatment in the head and neck region, radiation-chemotherapy should be considered in some human papilloma virus-positive cases.