A comprehensive characterization of lymphoepithelial cyst associated with the pancreas

Lymphoepithelial cyst of the pancreas is a rare but distinctive cystic lesion lined by a mature, keratinizing squamous epithelium and surrounded by lymphoid tissue.

To gain more insights into this entity, we describe 5 examples of lymphoepithelial cyst of the pancreas (2 of which were briefly described before) and compare them with similar cases in the literature for a total of 19 cases.

The male:female ratio was 16:3; patients' ages ranged from 32 to 73 years (mean and median 51). The lymphoepithelial cyst was incidentally found at autopsy in 4 patients (21%) or during evaluation for unrelated diseases in another 4 patients (21%). In the remaining 11 patients, the cyst was associated with abdominal pain in 9 (47% of all patients), nausea/vomiting in 3 (16%), diarrhea in 1 (5%), and nonspecific systemic symptoms in 6 (32%) (some patients had more than 1 associated symptom). Computed axial tomography scan, with or without ultrasonographic study, was done in 16 cases and uniformly displayed a single, well-circumscribed, cystic mass protruding beyond the surface of the pancreas; the rest of the pancreas was normal. Intraoperatively, the cyst was readily apparent once the lesser sac was entered and the surface of the pancreas exposed; the cyst was located at the head (3 cases), neck (1 case), body (6 cases), and tail (9 cases). Surgery was done for all 15 clinical cases and included local excision of the cyst with a thin rim of attached, underlying pancreas (6 cases), or distal pancreatectomy with (4 cases) or without (3 cases) splenectomy. Follow-up information, available in 7 cases, showed that all symptoms disappeared and the patients were alive and well up to 6 years after surgery.

This rare cyst of the pancreas has a uniform and characteristic clinicopathologic profile, enabling easy and accurate diagnosis. Although the histogenesis of lymphoepithelial cysts is not known, they are benign and can be cured by local excision.