Squamous cell carcinoma of parotid gland associated with concurrent lymphoepithelial cysts and lymphoepithelial lesion: case report and proposed histogenesis

MRI findings of sporadic/simple lymphoepithelial cyst of the parotid gland

PURPOSE

This study aimed to determine the MRI features of sporadic/simple lymphoepithelial cyst (SLEC) of the parotid gland.

METHODS

Ten patients (seven men, three women; mean age, 60 years; age range, 38-77 years) with histopathologically and clinically proven SLEC of the parotid gland who underwent MRI before surgical resection were enrolled in this study. No enrolled patient had HIV infection or Sjögren syndrome. MRI findings of SLEC were retrospectively assessed.

RESULTS

We confirmed 10 SLECs larger than 10 mm with a mean maximum diameter of 26.6 mm (range, 12-42 mm). Nine patients (90%) had a single cyst, and one (10%) had a large cyst accompanied by small cysts (<10 mm) within the ipsilateral parotid gland. Eight SLECs (80%) were unilocular, and two (20%) were bilocular, with complete septa. Among seven SLECs (70%) with internal septa, five unilocular SLECs (50%) had incomplete septa. Six SLECs (60%) had eccentric cyst wall thickening, and five (50%) were surrounded by small solid nodules that were isointense relative to lymph node. On T1-weighted images, all cyst contents were homogeneously hyperintense relative to cerebrospinal fluid.

CONCLUSION

SLECs of the parotid gland are usually single unilocular lesions. Internal septa, eccentric cyst wall thickening, and small solid nodules surrounding the lesion were often observed. Cyst contents are always homogeneously hyperintense on T1-weighted images.

Clinicopathological and immunohistochemical features of the oral lymphoepithelial cyst: A multicenter study

BACKGROUND

Analyze the clinical, demographic, histopathological, and immunohistochemical features of oral lymphoepithelial cyst (OLEC).

METHODS

Samples were retrospectively retrieved from five oral pathology services. Clinical and demographic data were collected from patient charts. Histopathological and immunohistochemical (CD3 and CD20) features were evaluated. Data analysis involved descriptive statistics and bivariate analyses (P ≤ .05).

RESULTS

Seventy-seven cases were found among a total of 146 150 specimens (0.05%). OLEC was predominantly diagnosed in females (70.1%). Mean patient age was 46.51 years. The lesions arose mainly on the lateral border of the tongue (40.3%), measured up to 1 cm (61.0%), and were asymptomatic (64.9%). Twenty-four lesions (31.2%) were white. Forty-one cases (53.2%) presented lymphocytic inflammatory infiltrate with no specific arrangement. The cystic lining was composed of a non-keratinized stratified epithelium (59.7%) presenting hyperplasia (39.0%). Connection with the surface, epithelium was found in 23 cases (29.9%) and 31 (40.3%) cases had two or more cystic cavities. The lumen content was predominantly desquamated cells (48.1%). Subgemmal neurogenous plaque was found in 11/42 (26.2%) cases involving the tongue. CD20⁺ cells predominated in 36/63 cases (57.2%), and lymphocytic inflammatory infiltrate was not always continuous around the cystic cavity (52.4%).

CONCLUSION

Lymphoepithelial cyst is an uncommon lesion of the oral cavity. The present study offers the largest sample of OLEC for which clinical, demographic, histopathological, and immunohistochemical features were evaluated. The clinical and demographic findings were similar to those described in previous reports, but the microscopic analyses revealed interesting aspects of the cystic epithelium and the lymphocytic inflammatory infiltrate in OLEC.