Pancreas
Cystic and intraductal lesions
Lymphoepithelial cysts
Editor-in-Chief: Debra L. Zynger, M.D.
Topic Completed: 4 April 2019
Minor changes: 23 October 2020
Copyright: 2002-2021, PathologyOutlines.com, Inc.
PubMed Search: Lymphoepithelial cysts[TIAB] pancreas
Table of Contents
Definition / general | Essential features | ICD coding | Epidemiology | Sites | Pathophysiology | Etiology | Clinical features | Diagnostic criteria | Laboratory | Radiology description | Radiology images | Prognostic factors | Case reports | Treatment | Clinical images | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Cytology images | Sample pathology report | Differential diagnosis | Board review style question #1 | Board review style answer #1 | Board review style question #2 | Board review style answer #2Cite this page: Krogh K Lymphoepithelial cysts. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/pancreaslymphoepithelial.html. Accessed January 19th, 2021.
Definition / general
- Extremely rare, nonneoplastic, true cyst lined by squamous epithelium with abundant lymphoid tissue
- Histologically similar to branchial cleft cysts arising in the neck
- First described in 1985 (Pathologe 1985;6:217)
- No association with salivary gland lymphoepithelial cysts
Essential features
- Consists of a squamous epithelial-lined cyst with surrounding lymphoid tissue
ICD coding
- ICD-10: K86.2 - cyst of pancreas
Epidemiology
- Mean age 56 years, range 35 – 82 years, 80% male (Mod Pathol 2002;15:492)
- 0.5% of pancreatic cysts
- From 1985 to 2016, 109 cases described in the literature (JOP 2013;14:250)
Sites
- Occurs anywhere in pancreas (head, body or tail) or extrapancreatic location
Pathophysiology
- May occasionally develop from epithelial remnants in lymph nodes (Hum Pathol 1991;22:924) or from accessory spleen in pancreas (Mod Pathol 1998;11:1171)
Etiology
- Etiology is unclear; still debated whether lymphoepithelial cysts are derived from embryonic remnants or pre-existing tissues with acquired inflammatory change (Medicine (Baltimore) 2015;94:e1758)
- Another possibility notes similarity to Warthin tumors in which lymphoid cells have an affinity for ductal epithelia and can induce their growth (Adv Anat Pathol 2011;18:98)
Clinical features
- Presents with nonspecific symptoms such as abdominal pain or nausea; ~50% present incidentally (JOP 2013;14:250)
- Not associated with immunosuppression or autoimmune diseases
Diagnostic criteria
- Often diagnosed on fine needle aspiration by cytopathologist
- Can be difficult to differentiate preoperatively from other pancreatic cystic lesions
Laboratory
- Cyst fluid has elevated CA19-9 levels and occasionally elevated CEA levels (diagnostic pitfall) (Mod Pathol 2010;23:1467)
Radiology description
- On CT, enhancement often equivocal; can look similar to serous cystic neoplasms, mucinous cystic neoplasms and intraductal papillary mucinous neoplasms
- Imaging varies and is similar to other pancreatic lesions (JOP 2013;14:15)
Radiology images
Images hosted on other servers:
CT
Large cystic mass
Prognostic factors
- Benign, does not recur or progress
Case reports
- 49 year old male with weight loss and diarrhea (Dig Surg 2000;17:309)
- 56 year old male with pancreatic cyst incidentally detected on a CT scan (Case Rep Gastrointest Med 2016;2016:5492824)
- 60 year old male with lymphoepithelial cyst (Case Rep Gastroenterol 2012;6:604)
- 66 year old male with sebaceous glands within a lymphoepithelial cyst (Surg Case Rep 2016;2:98)
- 66 year old male with lymphoepithelial cyst (Indian J Surg 2010;72:427)
Treatment
- Resection is curative
Clinical images
Images hosted on other servers:
Intraoperative view
Gross description
- Mean size 5 cm (range 1 – 17 cm)
- Often round and well demarcated from surrounding pancreas
- Either multilocular (60%) or unilocular (40%)
- Cysts contain serous or cheesy keratin-containing material
Gross images
Images hosted on other servers:
Well demarcated cysts
Pancreas tail
Microscopic (histologic) description
- Unilocular or multilocular cyst lined by squamous epithelium (nucleated or anucleated), with lymphocytes (intervening T lymphocytes) and germinal centers in the wall
- Combinations of squamous lining with other epithelial types (i.e. simple columnar) have been reported
- Lymphoid tissue, often a dense band
- With or without keratinous debris
- Occasional solid lymphoepithelial islands, rarely mucinous goblet cells
- Rare sebaceous differentiation, keratin granulomas, cholesterol clefts, multinucleated giant cells and foamy histiocytes may be present
Microscopic (histologic) images
Contributed by Katrina Krogh, M.D.
Lymphoepithelial cyst of the pancreas
Cytology description
- Numerous anucleated squamous cells, amorphous debris (Cancer 2006;108:501)
- May have mildly atypical mucinous glandular and parakeratotic epithelium
- Rare benign nucleated cells, usually no lymphocytes
Cytology images
Images hosted on other servers:
Squamous
epithelium,
keratinaceous debris
and lymphocytes
Keratinaceous debris
Sample pathology report
- Pancreas, cyst, excision:
- Lymphoepithelial cyst
Differential diagnosis
- Clinical differential diagnosis includes mucinous cystic neoplasms, intraductal papillary mucinous neoplasm (IPMN), intraductal oncocytic papillary neoplasm (IOPN) (but different histologically)
- Histological differential diagnosis:
- Dermoid cyst: has dermal appendages microscopically; younger mean age, prominent mucinous cells or respiratory mucosa
- Epidermoid cyst in intrapancreatic spleen: surrounded by splenic tissue (Acta Pathol Jpn 1991;41:916)
- Squamoid cysts: small, without lymphoid tissue
- Lymphangioma: has endothelial linings, positive for endothelial and lymphatic markers; small aggregates of lymphoid tissue rather than dense band
- Pseudocyst: no epithelial lining, no lymphoid stroma
Board review style question #1
Which of the following statements is true about the following pancreatic lesion?
- This lesion is more common than pancreatic mucinous adenocarcinoma
- This lesion does not undergo malignant transformation
- This lesion is found in females more commonly
- CEA is never elevated in cyst fluid
Board review style answer #1
Board review style question #2
Which of the following statements about this pancreatic lesion is true?
- This lesion is the most common cystic lesion of the pancreas
- This lesion is caused by immunosuppression or autoimmune dysfunction
- Foamy histiocytes can be present
- This lesion is associated with salivary gland lymphoepithelial cysts
Board review style answer #2
