Clinical and histopathological features of nasopalatine duct cyst: A 47-year retrospective study and review of current concepts

To evaluate the clinical and histopathological features of nasopalatine duct cysts (NDCs) stored in the archives of a referred Oral Pathology Service over a 47-year-period, and to review current concepts about these cysts. All NDCs were reviewed, and clinical data were obtained from the patient records. Thirty cases were re-evaluated microscopically by 2 oral pathologists. Among 14,564 cases, 30 (0.20%) were NDCs. Fifteen (50.0%) of the patients were female, and the mean age was 42.7 years. The lesions measured on average 2.37 ± 1.69 cm. Histologically, stratified squamous epithelium, alone or in combination with other epithelia, was present in 13 (46.6%) cases. Goblet cells and subepithelial hyalinization were common. Fourteen (46.6%) cases exhibited a slight degree of inflammation. Nerves were observed in 15 (50%) cases and mucous glands in 7 (23.3%). Hyaline ring granulomas (which is described here for the first time in NDC) and cholesterol crystals were not common. Knowledge of clinical-histopathological aspects of NDCs provides more accurate data about their nature and behavior. Our results suggest that the predominant epithelial lining of these cystic lesions is exclusively stratified squamous epithelium or combined with another type. Vessels, nerves, mucous glands and inflammatory infiltrate are frequently observed.