A Consideration of Papillary Squamous Cell Carcinoma of the Gingiva: A Case Study Involving the Immunohistochemistry of Proliferative Activity

Papillary squamous cell carcinoma (PSCC) is a rare variant of squamous cell carcinoma (SCC) having an exophytic papillary component. We report the case of a 60-year-old woman with oral PSCC of the gingiva. Histopathologically, the operative specimen was composed of exophytic papillary and invasive proliferations of atypical squamous epithelium, from which a pathological diagnosis of PSCC was made. On the Ki-67 labeling index, the exophytic area of PSCC (42.8%) was higher than the superficial area of SCC (20.7%) and papilloma (38.9%). The invasive area of PSCC (53.1%) was slightly higher than that of SCC (52.2%). The PSCC had high proliferative activity in both the exophytic and invasive areas, which reflected the PSCC characteristic features of papillary and invasive growths. Clinicians should check for the existence of PSCC in the oromaxillofacial region and provide treatment as they do for SCC.