Laparoscopic distal pancreatectomy for lymphoepithelial cyst of the pancreas.

Lymphoepithelial cysts are rare pancreatic lesions. This case report describes the first excision of such a lesion by laparoscopic distal pancreatectomy which is a recognized procedure for treatment of cystic pancreatic neoplasms. Our patient underwent complete excision of the lesion and has enjoyed complete resolution of his symptoms. Laparoscopic distal pancreatectomy may be a suitable choice for first-line therapy for such lesions.

CASE REPORT

A 48-year-old man presented with a 1-day history of sudden onset right upper quadrant abdominal pain radiating through to the back associated with nausea and vomiting. He was previously fit and well and had not suffered any loss of weight or change in bowel habits. A physical examination revealed only mild epigastric and right upper quadrant tenderness. All admission blood tests were normal other than a C-reactive protein of 40 mg/L (normal <2 mg/L). Plain x-rays of the chest and abdomen were also unremarkable. An ultrasound scan of the abdomen showed a dilated common bile duct at 9 mm and a well-defined (2.5-cm) lesion of low echodensity in the tail of the pancreas. Magnetic resonance imaging revealed a well-defined 3.5-cm mass attached to the superior aspect of the pancreatic tail. An ultrasound-guided biopsy of this lesion suggested a diagnosis of a benign squamous cyst. The decision was made to perform a laparoscopy and distal pancreatectomy and splenectomy, completely excising the lesion. This operation was done via 5 laparoscopic operating ports, initially mobilizing the distal pancreas and spleen. A sling was applied behind the pancreas, and an Endo GIA roticulator 60-mm stapler was used to excise the distal pancreas. The patient was discharged on postoperative day 3, although he did have a discharge of 10 mL of pancreatic juice per day that stopped spontaneously at 5 weeks. He always remained clinically well. The histology revealed a lymphoepithelial cyst, lined with keratinizing squamous epithelium-forming follicles with germinal centers in places. The patient's recovery was complicated by a minor pancreatic fistula that leaked a few milliliters per day. Three months later at his first outpatient review, the patient's fistula had healed and he was well.

DISCUSSION

Lymphoepithelial cysts of the pancreas are rare lesions, most of which have been reported in the literature as individual case reports, although Adsay et al[1] describe a series of 12 cases with a comprehensive summary of 64 other cases in the literature. The majority of patients are middle-aged and male, as in our case. Symptoms reported by patients included abdominal pain, nausea and vomiting, anorexia and weight loss, general malaise, and altered bowel habits. Many patients were asymptomatic, and the cyst was discovered as an incidental finding during imaging for other conditions. Computed tomography scanning was the most sensitive imaging modality in the diagnosis of these lesions.

Adsay et al[1] also give a comprehensive description of the pathological features of such cysts. In summary, they are round with a well-defined wall and often appear to be peripancreatic rather than intrapancreatic, as in our case. These features may aid radiological diagnosis. Their mean size in this series was 4.6 cm. The most characteristic histological feature of these cysts is the presence of lymphoid tissue, which differentiates these lesions from other types of pancreatic cyst.

Our case is the first report of excision of this type of cyst laparoscopically. Previous operations for such cysts include laparotomy and cyst excision, distal pancreatectomy with or without splenectomy and pancreaticoduodenectomy.[2] Laparoscopic distal pancreatectomy for cystic lesions remains a relatively new procedure, with only small numbers reported in the literature.[3,4] The majority of lesions resected in these studies were mucinous cystadenomas. The role of this procedure in the management of such lesions remains unclear as numbers are small and direct comparisons with open surgery have not been made, although in both of the above studies, the results of laparoscopic surgery compare favorably with those of open surgery in terms of complication rates and inpatient stay. The formation of a pancreatic fistula, as observed in our case, has an incidence of almost 35% following laparoscopic surgery[4] and most heal spontaneously. In the majority of published reports, complete excision of cystic lesions is achieved without disease recurrence, although follow up is generally short, so it will also be important to assess the long-term efficacy of this type of laparoscopic surgery when compared with that of open surgery.

CONCLUSION

We report the first case of laparoscopic excision of a lymphoepithelial cyst, a rare benign pancreatic lesion. Our patient has enjoyed complete resolution of his symptoms with no recurrence suggesting that this is an appropriate method for treating these lesions. The current literature suggests that laparoscopic surgery is preferable to open surgery in the treatment of cystic pancreatic lesions, although the studies involve small numbers and relatively short follow up.