True Solitary Pancreatic Cyst in an Adult: Report of a Case

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.

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.

Macrocystic pancreatic lesions: differentiation of benign from premalignant and malignant cysts by CT

OBJECTIVE

To assess useful CT features for differentiating benign from premalignant and malignant macrocystic pancreatic lesions.

METHODS

Seventy-four patients with pathologically proven macrocystic pancreatic lesions were enrolled: 17 benign cysts (macrocystic serous cystadenoma, n=12; congenital cyst; n=5) and 57 premalignant and malignant cysts (mucinous cystic neoplasm, n=28; intraductal papillary mucinous neoplasm of branch duct type, n=20; tumor with cystic change, n=9). Size, location, shape (lobulated, round or oval, or complex cystic with tubular cyst), wall thickness (thin, < or =1mm; thick, >1mm), internal surface (smooth or irregular), and other findings were analyzed with multiphasic CT with thin-section (2.5-3mm) images. CT features between two groups were compared using univariate and multivariate stepwise logistic regression analyses.

RESULTS

On univariate analysis, the differences for the shape (p=0.007), wall thickness (p=0.011), and internal surface (p=0.012) between benign and premalignant and malignant cysts were significant. A lobulated shape, a thin wall and a smooth internal surface were more frequent in benign cysts, whereas a round or oval shape or a complex cystic shape with tubular cyst, a thick wall and an irregular internal surface were more frequent in premalignant and malignant cysts. On multivariate analysis, the shape (p=0.002) and wall thickness (p=0.025) were significant CT features for differentiating benign from premalignant and malignant cysts.

CONCLUSION

Shape and wall thickness are the main CT features for differentiating benign from premalignant and malignant macrocystic pancreatic lesions.

A Rare Cystic Non-Functioning Neuroendocrine Pancreatic Tumor with An Unusual Presentation

This report describes a patient with a cystic non-functioning neuroendocrine glucagon cell pancreatic tumor presenting with demyelination of the optical nerve that had initially provoked marked monolateral reduced vision and had led to a suspected diagnosis of multiple sclerosis. Cystic degeneration is uncommon in endocrine pancreatic tumors due to their abundant vascular supply. Very few cases of cystic neuroendocrine non-functioning pancreatic tumors have been reported in the international literature. The presence of atypical neurological symptoms, such as sudden visual impairment, should be taken into account in the differential diagnosis for such tumors. The prognosis is poor, because most of these tumors are malignant and diagnosed at an advanced stage. The three-year disease-free survival of our patient, however, encourages the use of aggressive surgical treatment.