Solitary true cyst of the pancreas in adults. Report of three cases and review of the literature

Simple mucinous cyst: another potential cancer precursor in the pancreas? Case report with molecular characterization and systematic review of the literature

Cystic lesions of the pancreas may range from benign to precursors of pancreatic cancer. Simple mucinous cyst (SMC) is larger than 1 cm, has a gastric-type flat mucinous lining, and minimal atypia without ovarian-type stroma. We report a new case of pancreatic SMC, coupling a systematic review of the English literature mainly focused on their clinic-pathological features. We reviewed 103 cases of SMC in adults (73 women), averaging 57 (range, 26–70) years. The SMCs were located in the body-tail region of the pancreas in 60 (58%) cases, presenting as single cystic lesions in 94% of cases; 43% of patients were asymptomatic. A preoperative fine-needle aspiration of the cyst fluid detected amylase and carcinoembryonic antigen positivity in 71% and 76% of cases, respectively. Patients underwent surgery mostly for suspected malignancy; in 83% of cases, a standard pancreatic resection was performed. Mean SMC size was 4.9 (range, 1.5–12.0) cm. Mucins MUC5AC and MUC6 resulted positive in 77% and 81% of cases performed, respectively, whereas MUC2 was negative in all but one patient. The SMC from our institution was characterized by a KRAS somatic mutation. The diagnosis of SMC should be considered when a solitary pancreatic cyst larger than 1 cm is detected in asymptomatic patients. To establish a correct diagnosis, an extensive histologic/immunohistochemical analysis is essential. The presence of a KRAS mutation highlights that SMC may represent another potential pancreatic cancer precursor.

Laparoscopic spleen-preserving distal pancreatectomy in a solitary true pancreatic cyst

BACKGROUND

Solitary true pancreatic cysts (STPCs), or epithelial cysts, are benign lesions that are extremely rare in adult patients. Advances in radiographic techniques have improved the ability to identify pancreatic cystic lesions. We report a case of a large and symptomatic STPC in a 47-year-old female patient who was treated successfully with spleen-preserving laparoscopic distal pancreatectomy. We also review the clinical and pathologic features of all reported STPCs within the past 25 years.

DATABASE

To compose the review, we did a search of the international literature for STPCs that had occurred in adults. Fourteen related articles were found describing cases of STPCs. Clinical and pathologic information was collected for all of the reported pancreatic cysts, and a database was formed. STPCs are detected more frequently in women than in men. The mean age of occurrence is 43.2 years, and the mean cyst size is 5.6 cm. Fifty percent of true cysts are located in the head of the pancreas. Size and site are responsible for the symptoms caused, although 22.8% were asymptomatic. Diagnosis was made postoperatively in all cases by histopathologic studies. No case of malignancy was reported in any STPC.

CONCLUSIONS

STPCs are rare and benign lesions commonly discovered incidentally during abdominal imaging. Surgical treatment is considered the appropriate therapy for large and symptomatic STPCs. The definitive diagnosis is established by histopathologic and immunohistochemical studies.

Cystic lesions of the pancreas: radiologic-endosonographic correlation

Cystic lesions of the pancreas are relatively common findings at cross-sectional imaging; however, classification of these lesions on the basis of imaging features alone can sometimes be difficult. Complementary evaluation with endoscopic ultrasonography and fine-needle aspiration may be helpful in the diagnosis of these lesions. Cystic lesions of the pancreas may range from benign to malignant and include both primary cystic lesions of the pancreas (including intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, serous cystadenomas, pseudocysts, and true epithelial cysts) and solid neoplasms undergoing cystic degeneration (including neuroendocrine tumors, solid pseudopapillary neoplasms, and, rarely, adenocarcinoma and its variants). Familiarity with the imaging features of these lesions and the basic treatment algorithms is essential for radiologists, as collaboration with gastroenterologists and surgeons is often necessary to obtain an early and accurate diagnosis.

A new case of solitary true pancreatic cyst

A true cyst of the pancreas is extremely rare, and few cases have been reported in adult patients. The authors report a new case of this rare pathological entity. A 35-year-old male patient was admitted to our unit with a cystic mass, about 6cm in diameter, located in the pancreatic head, in proximity to the duodenum, vena cava, biliary tree and right kidney. Clinical features and imagery were suggestive for a benign neoplasm, as did surgical findings. Cystoduodenostomy was done. Histological finding revealed a cyst lined by cuboidal epithelium without morphologic alterations. Analysis of the cyst fluid showed a high level of CA 19-9 (10,000Uml(-1)). After 1-year follow-up, the patient was found to be doing well without any abdominal symptoms. Ultrasound images revealed no cyst recurrence.

Solitary true cyst of pancreas: report of a case and review of literature

CONTEXT

Solitary true cysts of the pancreas in adults are extremely rare, and only few cases have been reported in the literature. The etiology and natural history of these lesions remain unknown, and treatment is not standardized. We describe an additional resected case.

CASE REPORTS

A 55-year-old female who presented to us with a history of heaviness and pain in right upper abdomen for 1 year. CT scan of abdomen showed a large unilocular cyst in the region of the head of the pancreas. The patient underwent pancreatico-duodenectomy with binding pancreaticojejunostomy. The histology of cyst revealed true unilocular pancreatic cyst lined by cuboidal epithelium. She is well after 3 years of follow-up.

CONCLUSIONS

A preoperative work-up alone does not always allow an accurate diagnosis, but it is useful in determining lesion characteristics and guiding therapeutic decision-making. When surgery is indicated, a limited resection is warranted in most cases.

Management of cystic lesions of the pancreas

Pancreatic cystic lesions are being increasingly identified. Clinical decision making is driven by the differential diagnosis of the cyst and, for the asymptomatic patient, its likelihood of causing harm. The fundamental issue is whether the cyst is neoplastic, and, if so, what is its risk for malignant degeneration. High-resolution computed tomography provides detailed information about cyst structure and may facilitate differentiation from mucin-secreting tumors of the pancreas. Magnetic resonance imaging has the potential added advantage of determining communication between the cyst and pancreatic duct. Endoscopic ultrasound (EUS) imaging provides additional characterization of the lesion. While EUS morphology alone has limitations regarding definitive diagnosis, aspiration, and characterization of cyst, fluid contents may provide incremental information. Aspiration is well tolerated and safe, with a complication rate of less than 1%. In the absence of a history of pancreatitis, pseudocyst is quite unlikely, and the concern of a cystic neoplasm is paramount. In general, all symptomatic lesions should proceed to appropriate surgical resection. If preoperative characterization of the lesion will change management, EUS+FNA for cytology and fluid analysis (CEA) may characterize the lesion as mucinous, although cytology alone is rarely definitive. For those patients with benign-appearing lesions, such as classic appearance of a serous cystadenoma, observation alone seems appropriate. In some circumstances, EUS+FNA confirmation of a negative cytology and low fluid CEA can further provide evidence to support a monitoring approach and deferral of surgical intervention.

Solitary true cyst of the pancreas in an adult: report of a case

BACKGROUND

Solitary true cyst of the pancreas is rare in adults, and the differential diagnosis of cystic lesions of the pancreas is challenging.

AIM OF THE STUDY

To describe a solitary true cyst of the pancreas in an adult and discuss the differential diagnosis.

METHODS

A 50 yr old woman presented with a mass lesion in the right upper quadrant of the abdomen. Abdominal computed tomography showed a cystic lesion, with a maximum diameter of 12 cm, between the inferior surface of the liver and the ascending colon. The cyst was homogenous and had smooth edges. On magnetic resonance imaging, a unilocular cyst was seen that was low intensity on T1-weighted images and very high intensity on T2-weighted images. No connection between the cyst and the pancreatic ductal system was demonstrated on endoscopic retrograde cholangiopancreatography. Laparotomy was performed with a presumptive diagnosis of cystic tumor of the pancreas.

RESULTS

On pathologic examination, the cyst was serous and was lined with a single layer of normal cuboidal epithelium that was periodic acid Schiff stain negative. Meticulous examination failed to identify honeycomb-like microcysts characteristic of serous cystadenoma. The final diagnosis was a solitary true cyst of the pancreas.

CONCLUSION

The differential diagnosis of solitary true cyst from other cystic lesion of the pancreas usually is based on histology. Particular care must be taken to distinguish this lesion from macrocystic serous cystadenoma.

Simple pancreatic cysts: CT and endosonographic appearances

OBJECTIVE. This report describes the CT and endoscopic sonographic appearance of simple pancreatic cysts in three adults. CONCLUSION. Simple pancreatic cysts are typically an incidental finding in adults who have no history of pancreatic disease. The imaging characteristics of simple pancreatic cysts on CT and endosonography are similar to those of benign cysts.

Macrocystic serous cystadenoma of the pancreas: clinicopathologic features in seven cases

BACKGROUND

Serous cystic neoplasms of the pancreas are uncommon tumors classified as microcystic adenomas. In this article, the authors report clinico-pathologic features of seven cases of macrocystic variant of the serous cystadenoma.

METHODS

Seven patients (5 females and 2 males) with a diagnosis of cystic lesion of the pancreas were observed after 1995. Clinical, radiological, and pathologic features, including immunohistochemistry, were reported. Enzymes and tumor markers CEA, CA 19-9, CA 125, CA 15-3, CA 72-4, and mucin-like carcinoma-associated antigen (MCA) were investigated in the serum and cyst fluid of the patients. Cytology was also performed.

RESULTS

Six patients were symptomatic complaining abdominal pain. All cases had radiologic evidence of unilocular cyst of the pancreas. The suspected diagnosis was consistent with mucinous cystic neoplasm. Serum tumor markers were all in the normal range. After surgery, pathology showed in all cases a cyst lined with cuboidal, periodic acid-Schiff (PAS)-positive epithelium, without mucin content or atypia. Minute microcysts were found surrounding the main cavity. Immunohistochemical stains were positive for cytokeratin, CA19-9, CA15-3, CA 72-4, and MCA. CEA was unexpressed. CA 125 in the cyst fluid were found elevated in three cases and CA 19-9 in three cases. Cytology was negative in all cases.

CONCLUSION

When a unilocular pancreatic cyst is found, without history of pancreatitis and gallstones, having low serum tumor markers levels and negativity of CA 72-4 and MCA in the cyst fluid, the diagnosis of the macrocystic variant of the serous cystadenoma may be suggested. At present, the diagnosis is still based on pathological examination after cyst removal.

[Cystic lesions of the pancreas]

Most cystic lesions of the pancreas are pseudocysts caused by acute or chronic pancreatitis. Congenital cysts are rare and may occur in congenital syndromes like von Hippel-Lindau syndrome. Cystic tumors of the pancreas may be difficult to distinguish clinically; however, because of their malignant potential, in particular in cases of mucinous types, diagnostic verification is crucial. Hence, in all cases of cystic lesions of the pancreas, which are not a sequela of an etiological confirmed acute or chronic pancreatitis, a cystic neoplasm must be ruled out. Differential diagnosis may be difficult even with ultrasonography, computertomography, endoscopic retrograde cholangiopancreatography and serum analyses; endoscopic ultrasound, magnetic resonance tomography and analysis of the cyst content may be of particular value. The therapeutic approach for pseudocysts is now well established and guided by symptoms and complications. If a cystic neoplasm is suspected, surgical resection of the complete lesion is warranted.

CONCLUSION

The most important differential diagnosis in all cystic lesions of the pancreas with atypical presentation includes a cystic neoplasm. Therefore complete resection is indicated whenever the suspicion cannot be ruled out.