Lymphoepithelial cyst of the pancreas: a rare case report and review of literature

Lymphoepithelial cysts of the pancreas: case report and review of the literature

BACKGROUND

Lymphoepithelial cysts (LECs) of the pancreas are a rare type of true pancreatic cysts and represent an estimated 0.5% of all pancreatic cystic lesions. They are benign lesions and have no malignant potential. However, they are hard to differentiate from malignant lesions because their imaging and clinical presentation vary greatly. Seeing as these are benign lesions which are increasingly found incidentally during imaging for other indications, correct diagnosis is important to prevent unnecessary intervention and morbidity.

CASE REPORT

We report the case of a 41-year-old female who presented with abdominal discomfort, bloating and dyspepsia. An abdominal computed tomography (CT) showed a large mass in the left fossa. We describe the diagnostic and therapeutic measures taken in this case.

METHODS

We reviewed the literature for common features of the LEC. We grouped common imaging and histological features of the LEC of the pancreas to provide easily identifiable characteristics to facilitate diagnosis. For the review, we focused on papers, mostly case reports, presenting these common characteristics. We also reviewed the literature for key topics that should be taken into account when considering therapeutic interventions in a patient with a possible diagnosis of a LEC.

CONCLUSION

Cysts of the pancreas are increasingly identified due to widespread use and improved resolution of cross-sectional imaging. To obtain the correct diagnosis, it is sometimes necessary to combine advanced imaging, i.e. CT and MRI-imaging, and endoscopic ultrasound with fine needle aspiration (EUS/FNA), while CA 19-9 also has diagnostic value. We summarize all diagnostic characteristics in a table for ease of use. Furthermore we summarized possible therapeutic interventions.

Lymphoepithelial cyst of the pancreas: can common imaging features help to avoid resection?

BACKGROUND

Differentiation of cystic pancreatic neoplasms remains a challenging task for radiologists regarding the main aim of identifying malignant and premalignant lesions.

PURPOSE

The study aimed to compare the radiological features of lymphoepithelial cysts (LEC) with other cystic pancreatic lesions, which could help to differentiate them in order to avoid unnecessary resection.

MATERIAL AND METHODS

We retrospectively reviewed 10 cases of resected and histopathologically confirmed LECs during a 12-year period with available imaging studies; 20 patients with mucinous cystic neoplasms (MCN), 20 patients with branch-duct intraductal papillary mucinous neoplasms (BD-IPMN), and 20 patients with serous cystic neoplasms (SCN) were selected to serve as control groups. Imaging findings as well as clinical data were analyzed.

RESULTS

The following imaging morphology of LEC was identified: simple cystic appearance (20%) and mixed cystic-solid appearance (80%) with either a diffuse subsolid component (30%) or mural nodule(s) (50%). All lesions revealed exophytic location with a strong male predominance (9:1). MCNs occurred exclusively in middle-aged women, IPMN in both sexes showed slight male predominance (13:7), and SCN showed female predominance (5:15). Median patient age in LEC (48.5, IQR 47-54.5) was significantly younger compared to IPMN (p < 0.001) and SCN (p = 0.02). Unenhanced CT attenuation of LEC was higher than MCNs (p = 0.025) and IPMNs (p = 0.021), showing no significant difference to SCN (p = 0.343).

CONCLUSION

The present study provides key radiological features of LEC for the differentiation from other cystic pancreatic lesions such as increased CT attenuation in the unenhanced phase, absence of a connection to the main pancreatic duct (MPD), and exophytic location. In addition to these imaging features, clinical data, such as male predominance in LEC, must be considered for the differentiation of cystic pancreatic lesions.

A Rare Presentation of Pancreatic Lymphoepithelial Cyst: A Case Report and Review

Pancreatic lymphoepithelial cyst (LEC) is a rare, benign collection of keratinizing squamous epithelial cells encapsulated by lymphoid tissue. Because of its limited data and nonspecific features that can mimic malignant lesions, LECs can lead to unnecessary operations. A 62-year-old male with a known pancreatic mass presented with abdominal pain. CT scan showed an increased mass in the pancreatic head, and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) revealed “rare fragments of benign-appearing squamous epithelium in a background of keratin debris, cyst contents, and scattered lymphocytes,” consistent with a lymphoepithelial cyst. Pancreatic LEC is an extremely rare lesion that comprises of only 0.5% of all pancreatic cysts. EUS-FNA has become the mainstay for diagnosing pancreatic LECs. Given the slow growing and benign nature, conservative management and observation is adequate for pancreatic LECs with excellent long-term outcome. With increasing number of imaging ordered by clinicians, it is anticipated that there will be a greater number of incidental pancreatic LECs detected. Thus, EUS-FNA should be utilized more frequently to help distinguish benign pancreatic LECs from premalignant or malignant lesions to avoid surgery.

The Value of Contrast-Enhanced Ultrasound Classification in Diagnosis of Pancreatic Cystic Lesions

Objective

To compare the consistency of contrast-enhanced ultrasound (CEUS) classification results with magnetic resonance imaging (MRI) and to investigate the diagnostic value of CEUS classification in pancreatic cystic lesions.

Methods

84 cases of pancreatic cystic lesions were enrolled in this study. According to the CEUS classification methods of previous study in our center, all the lesions were classified into four types: type I, unilocular cysts; type II, microcystic lesions; type III, macrocystic lesions; and type IV, cystic lesions with enhanced solid components. The consistency of CEUS and MRI typing results was analysed. Among the 84 cases, 45 cases had pathological results. The CEUS results were compared with the pathological results, and the diagnostic value of CEUS classification in diagnosing pancreatic cystic lesions was explored.

Results

Among the 84 cases, CEUS diagnosed 8 cases of type I, 24 of type II, 8 of type III, and 45 of type IV. MRI diagnosed 10 cases of type I, 25 of type II, 7 of type III, and 43 of type IV. The classification typing results of CEUS were highly consistent with that of enhanced MRI (kappa value: 0.852). Among the 45 cases with pathological results, the diagnostic accuracy of each type was 91.1%, 95.6%, 93.3%, and 88.9%. The accuracy of CEUS and MRI in diagnosing pancreatic cystic lesions was 75.56% (34/45) and 80% (36/45), respectively. The diagnostic accuracy of CEUS had no significant difference from that of MRI (P=0.687).

Conclusion

The classification results by CEUS and MRI are in excellent agreement. The classification of pancreatic cystic lesions by CEUS is significantly helpful for clinical diagnosis.

Lymphoepithelial cyst of the pancreas: A case report and summary of imaging features of pancreatic cysts

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A lymphoepithelial cyst (LEC) of the pancreas is a benign and rare lesion.

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A pancreatic LEC is difficult to be diagnosed and differentiate from the malignancy preoperatively.

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We summarized the imaging features of pancreatic cysts to differentiate from the malignancy.

Introduction

A lymphoepithelial cyst (LEC) of the pancreas is a benign and rare lesion that is difficult to diagnose preoperatively based on imaging studies.

Presentation of case

We report a case of a 49-year-old man who presented with weight loss and diarrhea. The serum carcinoembryonic antigen and carbohydrate antigen 19-9 levels were slightly elevated to 6.7 ng/mL (reference value <5.0 ng/mL) and 45 U/mL (reference value <37 U/mL), respectively. Computed tomography showed a large cystic mass with internal septa in the pancreatic tail. The cystic wall and the septa showed enhancement while the cystic contents remained unenhanced. Magnetic resonance imaging (MRI) demonstrated a multiple-ball-like lesion with low signal intensity on T1-weighted image and high signal intensity on T2-weighted image. Diffusion-weighted MRI showed high signal intensity in the central and iso-signal intensity in the peripheral portions of the cystic lesion. The cystic wall and septa showed high signal intensity, and the cystic contents showed low signal intensity on an enhanced MRI. Endoscopic ultrasonography showed a cyst with multiple high-echoic lesions in the pancreatic tail. A mucinous cystic neoplasm and branch duct intraductal papillary mucinous neoplasm were considered among the differential diagnoses, and we performed distal pancreatectomy with concomitant splenectomy and lymphadenectomy for both diagnostic and therapeutic purposes. Histopathological findings revealed that the cystic wall was lined by stratified squamous epithelium, and several lymphoid follicles and a few sebaceous glands were observed within the cystic wall without hair follicles, leading to the final diagnosis of an LEC.

Conclusion

We report a rare case of a pancreatic LEC, which was difficult to be diagnosed and summarize the imaging features of pancreatic cysts to differentiate from the malignancy preoperatively.

Lessons learned from 29 lymphoepithelial cysts of the pancreas: institutional experience and review of the literature

BACKGROUND

Lymphoepithelial cysts (LECs) are rare pancreatic cystic lesions. Since LECs are benign, preoperative diagnosis is important to differentiate from a cystic neoplasm and avoid unnecessary surgery. The aim of this study was to identify clinical, radiographic and cytopathologic features associated with LECs.

METHODS

A retrospective review was performed of patients diagnosed with LEC between 1995 and 2017 at our hospital. Clinicopathologic and radiographic imaging features were documented.

RESULTS

Of 29 patients with pancreatic LEC, 22 underwent surgical resection. The majority were male (n = 24) with a median age of 55 years (range, 21-74). During the evaluation, all patients underwent a CT, with endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) biopsy (n = 22) and/or MRI/MRCP (n = 11) performed in a smaller number of patients. A combination of exophytic tumor growth on imaging and the presence of specific cytomorphologic features on the EUS-FNA cytology biopsy led to the correct diagnosis of LEC and prevention of unnecessary surgery in 7 patients.

DISCUSSION

Differentiating LECs from premalignant pancreatic cystic neoplasms remains difficult. Findings of an exophytic growth pattern of the lesion on abdominal imaging and the presence of specific cytomorphologic features in the EUS-FNA biopsy could help clinicians diagnose LEC preoperatively.

An Unusual Suspect: Lymphoepithelial Cyst of the Pancreas

Lymphoepithelial cysts (LECs) of the pancreas are benign, rare pancreatic cysts that are found predominantly in men. These cysts can present as a diagnostic conundrum given their rarity and difficulty of distinguishing these cysts from those with malignant potential. We present an incidental case of a LEC in a middle-aged man.

Endoscopic ultrasound characteristics of pancreatic lymphoepithelial cysts: A case series from a large referral center

BACKGROUND AND OBJECTIVES

Lymphoepithelial cysts (LECs) of the pancreas are benign lesions that can mimic cystic neoplasms on imaging. Endoscopic ultrasound (EUS) features have not been well described. We aimed to describe the clinical and EUS characteristics of LECs and the present outcomes of management at a high-volume referral center.

MATERIALS AND METHODS

We identified patients who underwent EUS and were found to have LECs based on fine-needle aspiration (FNA) cytology or surgical pathology from existing databases. EUS features, imaging characteristics, and pathology results were described.

RESULTS

Sixteen patients were found to have 17 LECs. The mean size was 33 mm ± 15 mm. Locations within the pancreas included 10 lesions in the tail, 3 in the body, 1 in the uncinate process; the remaining 3 were exophytic. Six lesions were anechoic, 6 were hypoechoic, and 5 had mixed echogenicity. Nine lesions had mixed solid/cystic components, 7 were purely cystic, and 1 was solid. Cyst fluid was thick or viscous in six cases and thin in three. Eleven patients had diagnostic cytopathology. Six patients ultimately underwent surgery due to symptoms, nondiagnostic FNA, or other clinical concerns for malignancy.

CONCLUSIONS

Pancreatic LECs have variable morphology and echogenicity on EUS, but the appearance of a cyst with variable solid and cystic components combined with the appearance of thick, turbid, and viscous aspirate should raise suspicion for an LEC. The majority of patients with LECs at our center avoided surgery for LECs on the basis of diagnostic EUS-FNA.

Lymphoepithelial Cyst of the Pancreas

Lymphoepithelial cyst (LEC) of the pancreas is an extremely rare, benign pancreatic cystic lesion that is difficult to differentiate preoperatively from other cystic pancreatic lesions. LEC may have malignant potential. Here, we describe a case of LEC of the pancreas - initially suspected to be a mucinous cyst neoplasm - in an elderly man presenting with abdominal pain, who went on to have a distal pancreatectomy and splenectomy. We also review the relevant literature and discuss implications for the diagnosis and management of this rare lesion.

Symptomatic lymphoepithelial cyst of the pancreas: successful treatment without pancreatic resection

Lymphoepithelial cysts (LECs) of the pancreas are rare benign lesions with unknown pathogenesis. LECs are true cysts that mimic pseudocysts and cystic neoplasms making diagnosis challenging. We report a case of a symptomatic LEC of the pancreas in a 67-year-old man who had severe epigastric pain. Workup including computed tomography and endoscopic ultrasound were non-diagnostic. The patient underwent attempted surgical resection; however, the mass was unresectable. The mass was enucleated and drained, and pathology returned LEC. The patient underwent a normal postoperative course and remained symptom free. Most LECs are diagnosed after an extensive pancreatic resection for suspicious cystic masses. The aim of this report is to show that operative management of LECs should not be limited to pancreatic resections. Excision and enucleation of LEC of the pancreas is a better alternative than an extensive pancreatic resection. Preoperative diagnosis of LECs appears to be the limiting factor.

Simultaneous Occurrence of a Rare Pancreatic Lymphoepithelial Cyst and Duodenal Mesenteric Castleman's Disease: a Case Report

Pancreatic lymphoepithelial cyst is a rare pancreatic lesion of undetermined pathogenesis, which is a true pancreatic cyst. Castleman's disease is a rare lymphoproliferative disorder, and a mesenteric location is unusual. The simultaneous occurrence of the two diseases are rarer than metachronous ones and has not been reported to date. We present a case report of a patient with simultaneous occurrence of pancreatic lymphoepithelial cyst and duodenal mesenteric Castleman's disease.

DC-CIK biotherapy for a recurrent benign lymphoepithelial lesion of the salivary gland: A case report and literature review

A benign lymphoepithelial lesion (BLEL) is an idiopathic inflammation of the parotid gland, characterized by hyperplasia, lymphocyte infiltration and the formation of epimyoepithelial islands, as well as atrophy of the gland parenchyma. Common treatment methods include immunosuppression and glucocorticoid therapies, in addition to surgical dissections. Cytokine-induced killer (CIK) cells sensitized to specific antigens by dendritic cells (DCs) are used in DC-CIK biotherapy. The present study reports the case of a 22-year-old female suffering from a postoperative recurrent BLEL on the left parotid gland, which was gradually increasing. Following initial unsuccessful conservative treatment attempts, a 10-day course of DC-CIK therapy was initiated, after which the lesion in the gland area was reduced in size and local infection and skin ulcerations were improved. DC-CIK biotherapy was continued for three months (four sessions of 10-day treatments with a 10-day break in between) until the lesion disappeared and the skin ulceration was healed. Computerized tomography scans of the parotid gland revealed complete remission of the primary lesion and recovery of the bone destruction. The patient was discharged and remained stable with no sign of recurrence during a 10-month follow-up period. In the present case report, a successful DC-CIK adoptive cellular immunotherapy treatment for a BLEL was described for the first time.

Lymphoepithelial cysts of the pancreas:a management dilemma

Pancreatic lymphoepithelial cysts (LECs) are rare, benign lesions that are typically unexpected post-operative pathological findings. We aimed to review clinical, radiological and pathological features of LECs that may allow their pre-operative diagnosis. Histopathology databases of two large pancreatic units were searched to identify LECs and notes reviewed to determine patient demographic details, mode of presentation, investigations, treatment and outcome. Five male and one female patients were identified. Their median age was 60 years. Lesions were identified on computed tomography performed for abdominal pain in two patients, and were incidentally observed in four patients. Five LECs were located in the tail and one in the body of the pancreas, with a median cyst size of 5 cm. Obtaining cyst fluid was difficult and a largely acellular aspirate was yielded. The pre-operative diagnosis was mucinous cystic neoplasm in all patients. This series of patients were treated distal pancreatectomy and splenectomy. A retrospective review of radiological examinations suggested that LECs have a relatively low signal on T2 imaging and a high signal intensity on T1 weighted images. LECs appear more common in elderly males, and are typically incidental, large, unilocular cysts. Close attention to signal intensity on MRI may allow pre-operative diagnosis of these lesions.

Non-neoplastic epithelial cysts of the pancreas: a rare, benign entity

OBJECTIVES

With the increased use of cross-sectional radiologic imaging in recent years, cystic lesions of the pancreas are being diagnosed with greater frequency. While pseuodocysts have historically accounted for the majority of benign pancreatic cysts, there are a number of rare, benign cystic lesions of the pancreas that can mimic neoplastic cysts. The objective of this study was to review a single institution's experience with these benign cystic lesions of the pancreas.

METHODS

We conducted a retrospective analysis of all patients who underwent surgical resection for pancreatic disease from 2005 to 2012 at our institution. Out of a total of 947 pancreatic resections, we identified those cases performed for cystic disease, and focused upon the clinicopathologic data of patients with non-neoplastic pancreatic cysts.

RESULTS

Of the 947 pancreatic resections, 256 (27%) were performed for cystic disease. Sixteen cases (6.3%) out of the total of 256 pancreatic operations performed for cystic disease were found to have non-neoplastic cystic lesions of the pancreas. Preoperative imaging revealed primary lesions in all patients, eight of which were found incidentally. Of these lesions, 14 were suspected preoperatively to be mucinous neoplasms and two to harbor pancreatic adenocarcinoma. However, postoperative pathology revealed eight patients with ductal retention cysts, three squamoid cysts, one mucinous non-neoplastic cyst, one congenital ciliated foregut cyst, one lymphoepithelial cyst, and two endometrial cysts. Two patients had complications postoperatively, one pancreatic fistula and one SMV thrombosis. Both complications resolved with conservative management.

CONCLUSIONS

Non-neoplastic epithelial pancreatic cysts are rare, benign lesions. In our institutional experience, these lesions are often indistinguishable from cystic neoplasms of the pancreas preoperatively. As such, many of these lesions are resected unknowingly. It is important for the clinician to be well informed of the nature of these lesions, in the hopes to avoid unnecessary resection whenever possible.

Pancreatic cysts: etiology, diagnosis and management

Pancreatic cysts involve a wide spectrum of pathologies from post-inflammatory cysts to malignant neoplasms. Pancreatic pseudocysts, serous cystadenomas, mucinous cystadenomas, intraductal papillary mucinous neoplasms (IPMNs) and solid pseudopapillary tumors occur most frequently. Differential diagnosis involves the following imaging investigations: transabdominal ultrasonography (TUS), contrast enhanced ultrasonography (CEUS) and endoscopic ultrasonography (EUS), computed tomography (CT), magnetic resonance (MR) and magnetic resonance cholangiopancretography (MRCP), endoscopic retrograde cholangiopancretography (ERCP). The cyst fluid cytology is performed in difficult differential diagnosis between pseudocysts and benign and potentially malignant or malignant tumors. Most frequently, viscosity, amylase, CEA and CA 19-9 levels are determined. Imaging findings should be correlated with cytology. The management depends on the cyst type and size. Small asymptomatic pseudocysts, serous cystadenomas and branchduct IPMNs should be carefully observed, whereas symptomatic large or uncertain serous cystadenomas and cystadenocarcinomas, mucinous cystadenomas and cystadenocarcinomas, main-duct IPMNs and large branch-duct IPMNs with malignant features, serous and mucinous cystadenocarcinomas, and solid pseudopapillary tumors require surgery. Pseudocysts are usually drained. Percutaneous / EUS-guided or surgical cyst drainage can be performed. Complicated and uncertain pseudocysts and cystic tumors need surgical resection. The type of surgery depends on cyst location and size and includes proximal, central, distal, total pancreatectomies and enucleation.