Side-branch Intraductal Papillary Mucinous Neoplasms Research Articles

The role of MRI in the diagnosis and follow-up for cystic pancreatic laesions

Introduction: With the widespread use of cross-sectional imaging and the technical developments particularly computed tomography (CT) and magnetic resonance imaging (MRI), and the continuous improvement in the image quality of these techniques, the diagnosis of incidental pancreatic cysts has increased in the last decades. These techniques have allowed improved spatial and contrast resolution especially. MR cholangiopancreatography demonstrating the morphologic features of the cyst (septa and mural nodules), the presence of communication between the cystic lesion and the pancreatic duct, and evaluating the extent of pancreatic ductal dilatation. The cystic lesions includes non-neoplastic lesions (i.e. pseudocyst) and cystic neoplasms [serous cystadenomas(SCA), mucinous cystic neoplasms and intraductal papillary mucinous neoplasms (IPMN)]. Mucin-producing neoplasms, except side branch IPMN(Sb-IPMN), have malignant potential.

Histopathologic Findings of Multifocal Pancreatic Intraductal Papillary Mucinous Neoplasms on CT

The criteria for resection of solitary pancreatic side-branch intraductal papillary mucinous neoplasm (IPMN) have been well described by the Sendai consensus statement. However, the management of multiple pancreatic cystic lesions is less certain, with no clear guidelines in the literature to date. The purpose of this study was to evaluate the histopathologic findings in pancreatic IPMNs in patients with multiple (≥ 4) pancreatic cysts. The CT scans of all patients with a pathologically proven IPMN at our institution were reviewed, and a total of 52 patients with four or more pancreatic cysts were found. Each case was reviewed for the number of cysts and the presence of signs of invasive malignancy including a coexistent solid pancreatic mass, pancreatic ductal dilatation, and mural nodularity. A total of 52 patients (19 men, 33 women; mean age, 71.8 years) were found to have multifocal IPMNs, defined as four or more cysts, on CT. Of these 52 patients, nine also had evidence of a solid pancreatic mass on CT. Retrospective review of the pathologic results for the remaining 43 patients (17 men, 26 women; mean age, 71.76 years) showed 18 cases of an IPMN with either high-grade dysplasia or a coexistent invasive carcinoma. Most important, 37% (7/19 patients) had no CT findings of an invasive malignancy according to the Sendai criteria (i.e., cysts ≥ 3 cm in the axial plane, main pancreatic ductal dilatation ≥ 6 mm, or mural nodularity within a cyst) but were found to have an IPMN with either high-grade dysplasia or invasive carcinoma. When the pancreas contained 10 or more cysts, high-grade dysplasia or invasive carcinoma tended to be more likely than low- or intermediate-grade dysplasia (odds ratio, 3.83; 95% CI, 0.87-16.8; p = 0.075). The presence of multiple pancreatic cysts should be looked on with suspicion, particularly when there are a large number of cysts, even when none of the cysts individually meet the imaging criteria for resection according to the Sendai consensus recommendations. At the very least, these patients need to be followed very closely.

Diagnosis and Management of Cystic Pancreatic Lesions

The purpose of this review is to outline the management guidelines for the care of patients with cystic pancreatic lesions. The guidelines are as follows: Annual imaging surveillance is generally sufficient for benign serous cystadenomas smaller than 4 cm and for asymptomatic lesions. Asymptomatic thin-walled unilocular cystic lesions smaller than 3 cm or side-branch intraductal papillary mucinous neoplasms should be followed up with CT or MRI at 6 and 12 months interval after detection. Cystic lesions with more complex features or with growth rates greater than 1 cm/year should be followed more closely or recommended for resection if the patient's condition allows surgery. Symptomatic cystic lesions, neoplasms with high malignant potential, and lesions larger than 3 cm should be referred for surgical evaluation. Endoscopic ultrasound with fine-needle aspiration (FNA) biopsy can be used preoperatively to assess the risk of malignancy.

Synchronous Association of Cystic Pancreatic Neuroendocrine Tumor and Side-Branch Intraductal Papillary Mucinous Neoplasm Diagnosed by Endoscopic Ultrasound

Purpose: Cystic pancreatic neuroendocrine tumor (PNET) is a very rare pancreatic neoplasm while intraductal papillary mucinous neoplasm (IPMN) is an increasingly recognized pancreatic cystic tumor. To best of our knowledge, concomitant association of cystic PNET and side-branch IPMN diagnosed by endoscopic ultrasound (EUS) and fine needle aspiration cytology (FNAC) has not been reported in the literature. We are reporting a patient with this extremely rare association. A 74-year-old woman was referred to our institution due to intermittent epigastric abdominal pain. A CT scan of the abdomen at an outlying facility showed a 1.7-cm cystic lesion in the body of the pancreas as well as a 3.5-cm septal spherical cystic mass with calcification near the tail of the pancreas. EUS was scheduled for further evaluation of the pancreas which showed an anechoic, round and a well-demarcated cystic lesion in the body of the pancreas measuring 16.8 mm × 14.3 mm in size. Communication with the pancreatic duct was identified raising the possibility of IPMN. FNA was performed and cytology was consistent with low grade branch duct IPMN. EUS examination of the pancreatic tail revealed a mixed anechoic and hypoechoic mass with both cystic and solid components measuring 35.1 mm × 25 mm in maximal dimensions. No communication with the pancreatic duct was identified. FNAC showed polygonal cells with granular cytoplasm and rounded monotonous nuclei that on immune staining were positive for synaptophysin, CD 56, and chromogranin A; consistent with a diagnosis of well-differentiated PNET. Subsequently, patient was referred for surgical resection. This case also demonstrates that concomitant pancreatic cystic masses with different EUS morphologic features mandates an individual FNA of each of the cysts for cytology and chemistry to make a definitive diagnosis of potentially coexisting cystic neoplasms.Table: [747] Comparison of the morphologic features and laboratory evaluation of the two pancreatic cystic massesFigure: [747] EUS: an anechoic cystic lesion in the body of the pancreas (red arrow) and a mixed anechoic & hypoechoic cystic lesion (yellow arrow) in the tail of the pancreas.Figure: [747] IPMN cell block displaying columnar tumor cells and back ground mucin (Left slide). PNET cell block showing tumor cells with rounded monotonous nuclei forming discrete aggregates (Right slide).

The role of GNAS mutation in diagnosis of mucinous pancreatic cysts.

e21048 Background: Pancreatic cysts pose a challenge in patient management primarily due to difficulties distinguishing non-mucinous cysts from potentially pre-malignant mucinous ones, and in determining the malignant potential of mucinous cysts. Mutations to the GNAS gene have been identified as a marker for intraductal papillary mucinous neoplasm (IPMN). [1,2] We evaluated the significance of GNAS mutation in diagnosis of pancreatic cysts. Methods: We retrieved archival DNA from 237 cyst fluids. 200 specimens were chosen with 100 KRAS mutant and 100 KRAS wild type in a range of CEA values. 37 specimens were chosen with a molecular diagnosis of aggressive biological behavior, to enrich for malignant IPMNs. We sequenced each fluid’s DNA from for codon 201 of GNAS. Molecular criteria for mucinous cysts included KRAS mutation, elevated DNA, or ≥2 high clonality LOH mutations. Results: Of the 237 specimens, 25 were not amplifiable due to degraded DNA, 52 (25%) had a GNAS mutation, and 160 had no GNAS mutation. Of the 52 GNAS mutated specimens, 5 were diagnosed as biologically aggressive based on significant associated mutations, 28 as statistically indolent based on associated molecular changes, and 19 as benign (no accompanying mutations). The proportion of GNAS mutations decreased with increasing molecular changes linked to malignancy. Data from [1] shows no statistical difference in frequency of GNAS mutation in side branch vs. main vs. mixed IPMNs (p= 0.46). Similarly, in our cohort, 6 cases had clear imaging features of a side branch IPMN, and of these 2 (33%) had a mutation in GNAS. Using molecular criteria for identification of mucinous cysts, 166 were mucinous and 71 non-mucinous. Incorporation of GNAS into the molecular determination of mucinous etiology identified 13 additional cases (7%). Conclusions: Use of GNAS increases sensitivity for detection of mucinous lesions. GNAS does not appear to correlate with molecular measures of biological aggressiveness. These findings confirm those in [1], that GNAS should be used in conjunction with a panel of molecular markers for evaluating the malignant potential of pancreatic cystic lesions.

530 High Grade Dysplasia and Adenocarcinoma are Frequent in Side-Branch Intraductal Papillary Mucinous Neoplasm Measuring Less Than 3cm on Endoscopic Ultrasound

530 High Grade Dysplasia and Adenocarcinoma are Frequent in Side-Branch Intraductal Papillary Mucinous Neoplasm Measuring Less Than 3cm on Endoscopic Ultrasound

Chirurgische Therapie intraduktaler papillär muzinöser Neoplasien des Pankreas

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas constitute an increasingly recognized entity of cystic pancreatic tumors which are characterized by mucin production and epithelial growth within the pancreatic ducts and show a wide spectrum of morphologic variants. They may arise in the main pancreatic duct, its major side branches or in both (mixed type). Furthermore, IPMNs are considered as precursor lesions to pancreatic adenocarcinoma. However, it is not clear what the time course of such potential neoplastic transformation might be and whether all lesions progress to malignant tumors. As currently no diagnostic test can reliably differentiate between benign and malignant tumors the majority of newly diagnosed IPMNs should be surgically resected. According to current treatment guidelines (Sendai criteria), only asymptomatic side branch IPMNs of less than 3cm in diameter without suspicious radiologic features, such as nodules, thickness of the cystic wall or size progression, should be treated conservatively without the need for surgical resection. Recently, this approach has become controversial due to a relevant number of reported Sendai negative IPMNs which revealed malignant transformation on final histological examination. The focus of this review is on the surgical treatment of IPMNs with regard to the current state of knowledge.

Current status on the diagnosis and management of pancreatic cysts in the Asia–Pacific region: Role of endoscopic ultrasound

Endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration (EUS-FNA) play increasingly prominent roles in the diagnosis and management of pancreatic cysts. The Asian Consortium of Endoscopic Ultrasound was recently formed to conduct collaborative research in this area. This is a review of literature on true pancreatic cysts. Due to the lack of systematic studies, there are no robust data on the true incidence of pancreatic cystic lesions in Asia and any change in over the recent decades. Certain EUS morphological features have been used to predict particular types of pancreatic cysts. Pancreatic cyst fluid viscosity, cytology, pancreatic enzymes, and tumor markers, in particular carcinoembryonic antigen, can aid in the diagnosis of pancreatic cysts. Hemorrhage and infection are the most common complications of EUS-FNA of pancreatic cysts. Pancreatic cysts can either be observed or resected depending on the benign or malignant nature, or malignant potential of the lesions. Guidelines from an international consensus did not require positive cytological findings to be present in their recommendation for resection, which included all mucinous cystic neoplasms, all main-duct intraductal papillary mucinous neoplasms (IPMN), all mixed IPMN, symptomatic side-branch IPMN, and side-branch IPMN larger than 3 cm. In patients with poor surgical risks, EUS-guided cyst ablation of mucinous pancreatic cysts is an alternative. As long-term prospective data on pancreatic cysts are still not available in Asia, management strategies are largely based on risk stratification by surgical risk and malignant potential. Gene expression profiling of pancreatic cyst fluid and confocal laser endomicroscopic examination of pancreatic cysts are novel techniques currently being studied.

Is It Safe to Follow Cystic Pancreatic Neoplasms if Immediate Surgery Is Not Undertaken?

Purpose: To characterize clinical outcomes and follow up in patients with pancreatic cystic neoplasms not undergoing surgical intervention. Methods: We searched our endoscopy database for data and included patients with pancreatic cysts between January 2005 and December 2009 with at least 12 months of clinical follow up. Inclusion criteria: Mucinous cystic neoplasms, side branch IPMN including those with Pancreatic Duct (PD) <6 mm without features of main duct IPMN, serous cystadenoma based on clinical, radiological and EUS-FNA features. Exclusion criteria: Main duct IPMN, pancreatic pseudocyst, mesenteric cysts, and pancreatic cysts that underwent surgical resection. Data on demographics, clinical presentation, CT findings at presentation and at follow up, EUS features, cyst fluid analysis, as well as clinical and radiological follow up were collected. Results: 49 patients were identified. Mean age was 68.6+/-10.9 years. 30 (61.2%) were females. Presentation included an incidental finding in 36 (73.5%), abdominal pain in 10 (20.4%) and weight loss in 3 (6.1%) patients. A solitary lesion was seen in 33 (67.3%) patients. Median size of largest cystic lesion on CT and EUS at initial presentation was 23.5 +/- 18.0 mm and 21.5 +/- 14.3 mm respectively. Locations included head in 19 (38.8%), body in 16 (32.7%), tail in 6 (12.2%), neck in 5 (10.2%), uncinate in 3 (6.1%) patients. Septae were seen in 12/49 (24.5%) patients. Other EUS findings included wall thickness in 5/49 (10.2%), intracystic component in 6/49 (12.2%), PD dilatation in 8 (16.3%) and possible cyst communication with PD in 11 (22.4%) of patients. Fluid was reportedly viscous in 17/49 (34.7%) aspirations. Mucin was seen on histopathology in 14 (28.6%) patients. Cyst CEA levels were available in 35/49 (71.4%) patients. In these 35 patients, cyst CEA level <192 ng/mL was seen in 28 (80%) and >192 ng/mL in 7 (20%) patients. A follow up CT study was available in 46/49 (93.9%) patients after a median follow up of 24.8+/-18.4 months. On follow up, cyst were seen to have regressed in size in 15 (30.6%), remained stable in size in 7 (14.3%) and increased in size in 22 (44.9%) patients. Among these 22 patients, median increase in cyst size was 5.1+/- 7.8 mm. 46/49 (93.9%) patients were alive with a median follow up of 25.5+/-15.3 months without any clinical or radiological evidence of invasive malignancy. Conclusion: Most cystic lesions of pancreas are found incidentally. It appears to be reasonably safe to follow pancreatic cysts for up to two years, including those considered to be mucinous but without overt malignancy that are not operated on for one reason or another.

Side-branch intraductal papillary mucinous neoplasms of the pancreatic head/uncinate: resection or enucleation?

IntroductionSide-branch intraductal papillary mucinous neoplasms (IPMN) of the pancreatic head/uncinate are an increasingly common indication for pancreaticoduodenectomy (PD). However, enucleation (EN) may be an alternative to PD in selected patients to improve outcomes and preserve pancreatic parenchyma. AimTo determine peri-operative outcomes in patients with side-branch IPMN of the pancreatic head/uncinate undergoing EN or PD compared with a cohort of patients with pancreatic adenocarcinoma (PA) undergoing PD. MethodsRetrospective review of a prospectively collected, combined, academic institutional series from 2005 to 2008. Of 107 pancreatic head/uncinate IPMN, enucleation was performed in 7 (IPMN EN) and PD was performed in 100 (IPMN PD) with 17 of these radiographically amenable to EN (IPMN PDen). During the same time period, 281 patients underwent PD for PA (Control PD). ResultsOperative time was shorter (p<0.05) and blood loss (p<0.05) was less in the IPMN EN group compared with all other groups. Peri-operative mortality and morbidity of all IPMN groups (IPMN EN, IPMN PDen) were similar to the Control PD group. Overall pancreatic fistulae rate in the IPMN EN group was higher than in the IPMN PDen and Control PD groups; however, the rate of grade C pancreatic fistulae was the same in all groups. ConclusionsPancreaticoduodenectomy for side-branch IPMNs can be performed safely. Compared with PD, enucleation for IPMN has less blood loss, shorter operative time and similar morbidity, mortality, hospital length of stay (LOS) and readmission rate. Enucleation should be considered more frequently as an option for patients with unifocal side-branch IPMN.

Development of pancreatic cancers during long-term follow-up of side-branch intraductal papillary mucinous neoplasms

Correction to: Development of pancreatic cancers during long-term follow-up of side-branch intraductal papillary mucinous neoplasmsEndoscopy 2010; 42(12): 1077-1084DOI: 10.1055/s-0030-1255971

Development of pancreatic cancers during long-term follow-up of side-branch intraductal papillary mucinous neoplasms

Side-branch intraductal papillary mucinous neoplasms (SB-IPMNs), and associated synchronous and metachronous pancreatic cancers are increasingly detected as imaging modalities become more sensitive. We investigated the natural history of SB-IPMN, and the incidence and characteristics of pancreatic cancers among patients undergoing long-term follow-up. We reviewed the clinical, imaging, and pathological features in 103 patients, diagnosed at the Aichi Cancer Center between September 1988 and September 2006 as having SB-IPMN, and conservatively followed up for ≥ 2 years (median 59 months) based on an endoscopic ultrasonography (EUS) database. 74 (71.8 %) patients had nonprogressive lesions. Overall, six patients (5.8 %) developed pancreatic cancers during follow-up, with intraductal papillary mucinous (IPM) carcinoma in four, and ductal carcinoma of pancreas that was not IPMN in two patients. Of the six pancreatic cancers, five were diagnosed at a resectable stage. The 5-year and 10-year actuarial rates of development of pancreatic cancer were 2.4 % and 20.0 %, respectively. Although, at the last follow-up, cyst size, main pancreatic duct (MPD) diameter, mural nodule size, and frequency of metachronous and/or synchronous cancers of other organs were significantly higher in patients who developed IPM carcinoma, resected SB-IPMNs without mural nodules and dilated MPDs had no IPM carcinomas. The frequency of pancreatic cancers is high on long-term follow-up of SB-IPMN. Although conservative management is appropriate for selected patients, regular and long-term imaging, especially by EUS is essential, even if SB-IPMN remains unchanged for 2 years. Presence of mural nodule and dilated MPD seem to be more appropriate indicators for resection than cyst size alone for SB-IPMNs.

IPMN Natural History: A Story Very Much Still Evolving

Purpose: First described in 1982, intraductal papillary mucinous neoplasm (IPMN) has been recognized with increasing frequency in patients with and without symptoms referable to the pancreas. The literature on IPMN has been fast accumulating, including an international consensus guidelines publication in 2006. However, much remains to be learned about the natural history of this entity as evidenced by the case report below: In 2000, a 79-year-old white nonsmoker, tea-totaler asymptomatic woman sought medical attention because of the new diagnosis of ovarian cancer in her older sister. Her CA 19-9 was 200 (nl <37), leading to a CT showing small pancreatic cysts. For the ensuing 3 years, CA 19-9 fluctuated between 116 and 444. Because of the CA 19-9, patient was seen at our institution in 2003 when her CA 19-9 was 129. Since then, multiple MRCP, CT pancreas protocol, EUS examinations, and one ERCP were performed at annual interval. In 2008, a secretin MRCP was compared to her first MRCP in 2003, demonstrating no change. Seen were multiple sub-centimeter cysts throughout the pancreas, some of which were connected to a nondilated pancreatic duct, consistent with side branch IPMN. Because of the stability of these lesions and the patient's age, these lesions were reported by Radiology as being of doubtful clinical significance. However, a repeat MRCP 13 months later showed a new 2 cm mass at the head of the pancreas. EUS-guided biopsy showed adenocarcinoma. The patient described herein lacked all of the features commonly thought of as high-risk predictors for progression to high grade dysplasia or malignancy. Specifically, she had side branch IPMN, with pancreatic duct diameter <10 mm, cysts <10 mm, and no internal cystic nodules. Yet, her pancreas underwent a malignant transformation, contrary to published reports of majority (84%) having no change within a 5-year follow-up and no carcinoma. The possibility therefore exists that the so-called low risk group of patients with side-branch IPMN are quite heterogeneous, with some capable of developing adenocarcinoma. Until the risk factor profile for this subgroup is defined, clinical management of patients with IPMN will require individualized flexibility and IPMN natural history is still very much an evolving story.

Coexistent Serous Cystadenoma and Intraductal Papillary Mucinous Neoplasm of Pancreas? Yes, It Can Happen!

Purpose: A 63-year-old white male presented with six week history of intermittent, mild right flank discomfort. His physical examination, apart from moderate obesity, was unremarkable. His serum CA 19-9 and serum amylase levels were normal. A biphasic CT scan of abdomen revealed a 2cm water density lesion located in the posterior pancreatic tail. Endoscopic ultrasound (EUS) revealed three cysts ranging in size from 4mm to 10mm in pancreas body and a multi-loculated cystic lesion measuring 2.1cmx1.4cm (lesion #1) located in the pancreas tail. The sonographic features were suggestive of multiside branch intraductal papillary mucinous neoplasm (MS-IPMN) (Image 1, arrowhead). Immediately inferior to the largest MS-IPMN lesion and adjacent to the left kidney, a well-circumscribed, more solid-appearing lesion with anechoic (microcysts) intervening spaces was seen (lesion# 2) (Image 1, arrow). Lesion #2 measured 22mm in the greatest diameter. Based on sonographic features of lesion #2, a differential diagnosis of likely synchronous serous cystadenoma (SCT) versus other cystic solid lesions (neuroendocrine tumor) was rendered. An EUS guided fine needle aspiration (EUS-FNA) using a 22 G needle of lesion#1 yielded 3cc of clear viscous fluid with elevated CEA 203.7 ng/ml and amylase 17,514 U/L levels. EUS-FNA cytology was consistent with a side branch IPMN. The location of lesion #2 immediately inferior to the MS-IPMN precluded safe and uncontaminated advancement of the FNA needle. A subsequent distal pancreatectomy and splenectomy revealed synchronous SCT and MS-IPMN. This is an unusual case of concomitant SCT and IPMN. This report highlights the clinical impact of EUS and EUS-FNA in evaluation and management of cystic lesions of the pancreas and illustrates the limitation of biphasic pancreas protocol CT to ascertain the presence of multiple MS-IPMN lesions in the pancreas.Figure

Completely Laparoscopic Subtotal Pancreatectomy with Splenic Artery Preservation

IntroductionLaparoscopic distal pancreatectomy has emerged as an attractive minimally invasive alternative for selected patients. Although technically challenging, distal pancreatectomy with splenic artery preservation has consistently been correlated with reduced blood loss and perioperative morbidity in multiple studies. Herein presented is our technique for completely laparoscopic (non-hand-assisted) subtotal pancreatectomy with splenic artery preservation (LSP-SAP). MethodsAn 87-year-old woman with an incidentally identified 3-cm cystic lesion in the pancreatic body–tail interface underwent EUS, which supported side-branch intraductal papillary mucinous neoplasm. The patient subsequently underwent laparoscopic resection. A completely laparoscopic procedure was performed using a four-trochar technique. The tail and body of the pancreas were dissected off of the retroperitoneum along the embryologic plane and separated from the colonic splenic flexure. Next, the splenic artery was dissected, isolated, and preserved, while the splenic vein was dissected off the ventral pancreas up to the level of the splenic–portal vein confluence. The technique employed a bipolar cutter-sealing device for dissection and hemostasis. Pancreatic parenchymal transection was performed with a standard vascular load endomechanical stapling device. ResultsTotal procedure time was 210 min, and the estimated blood loss was 200 mL. Postoperatively, the patient was admitted, advanced to regular diet the next day, and discharged home on postoperative day 3. The pathological review of the specimen revealed high-grade dysplasia with a non-invasive malignant component, classified as intraductal carcinoma. Foci of PanIN 1–3 were identified with no high grade dysplasia at the surgical margin. Five lymph nodes were included in the specimen and were negative for malignancy. ConclusionCompletely LSP-SAP can be safely performed in selected patients. This procedure may be an optimal alternative to open surgery.

Comparative Performance of MDCT and MRI With MR Cholangiopancreatography in Characterizing Small Pancreatic Cysts

The objective of our study was to compare MDCT with MRI-MR cholangiopancreatography (MRCP) in characterizing small pancreatic cysts (< or = 3 cm) and predicting aggressiveness. In a retrospective analysis, contrast-enhanced MDCT and MRI examinations of 30 patients with 38 pathologically confirmed small pancreatic cysts were reviewed. MDCT and MRCP studies were independently evaluated by two readers for cyst morphology, cyst characterization, and prediction of lesion aggressiveness, which included lesions with moderate-grade dysplasia, high-grade dysplasia (carcinoma in situ), and invasive carcinomas. The sensitivity of MDCT and MRI for the detection of each morphologic feature, accuracy for cyst characterization, and predictive values for aggressiveness were calculated. Of 38 lesions, 14 were side-branch intraductal papillary mucinous neoplasms (IPMNs), 12 mixed IPMNs, six mucinous cystic neoplasms, and six nonneoplastic cysts. On histopathology, 26 lesions were nonaggressive (six nonneoplastic cysts, six benign mucinous cystic neoplasms, 14 low-grade dysplasias in IPMNs), whereas 12 lesions revealed aggressive biology (eight moderate-grade dysplasias, four high-grade dysplasias in IPMNs). The sensitivity of MRCP for the detection of morphologic features was better than that of MDCT, but the differences were not statistically significant (p = 0.25-1). Interreader agreement and MDCT-MRI agreement for morphologic features were good to perfect (kappa = 0.7-1). The accuracy of MDCT and MRI was higher in classifying cysts as mucinous or nonmucinous than in determining a specific diagnosis (71-84.2% vs 39.5-44.7%, respectively), whereas the accuracy of the two techniques in characterizing cysts into nonaggressive and aggressive categories was similar (MDCT vs MRI, 75-78% vs 78-86%, respectively; p > 0.05). MRI enables more confident assessment of the morphology of small cysts than MDCT, but the accuracy of the two imaging techniques for cyst characterization is comparable. MDCT and MRI have high accuracy in classifying cysts into mucinous and nonmucinous categories and perform similarly in estimating histologic aggressiveness.

Pancreatitis is frequent among patients with side-branch intraductal papillary mucinous neoplasia diagnosed by EUS

Because of greater recognition and improved imaging capabilities, intraductal papillary mucinous neoplasms (IPMNs) are being diagnosed with increasing frequency. IPMNs of the main pancreatic duct cause symptoms and lead to pancreatitis. Side-branch (SB) IPMNs are thought to cause symptoms less frequently, and their association with pancreatitis is not well defined. Our purpose was to ascertain whether an association exists between SB-IPMN and pancreatitis. Single-center, retrospective study. Academic medical center. A total of 305 patients underwent EUS examinations between October 2002 and October 2006 for pancreatic cystic lesions. The main outcome measure was the frequency of acute or chronic pancreatitis that was not procedurally related. Thirty-two patients had SB-IPMNs, and 11 (34%) had pancreatitis. Three patients reported a single episode, and 8 patients reported having recurrent episodes of pancreatitis. Overall, 17 (53%) patients had symptoms possibly attributable to SB-IPMN. Female sex (73% vs 38%) and multiple pancreatic lesions (54% vs 24%) were more commonly seen in those with pancreatitis, but were not statistically significant factors. Larger cyst size or cyst fluid marker levels did not appear associated with pancreatitis occurrence. EUS-FNA demonstrated communication with the pancreatic duct in 94% and thick, mucinous fluid in 84%. Single-center, retrospective study. Pancreatitis was frequently associated with the presence of SB-IPMNs in our referral practice. SB-IPMNs should be considered in the differential diagnosis of patients with recurrent pancreatitis with cystic lesions seen on imaging studies. EUS-FNA was the most useful modality in helping to differentiate SB-IPMNs from other lesions.

Another Dimension in Magnetic Resonance Cholangiopancreatography

The purpose of this study was to compare 2-dimensional (2D) and 3D magnetic resonance cholangiopancreatography (MRCP) for image quality and diagnostic performance in the evaluation of pathologically verified intraductal papillary mucinous neoplasm (IPMN) of the pancreas. In this institutional review board-approved retrospective review, 21 patients (14 women and 7 men; mean age, 69 years; range, 43-93 years) who underwent 2D and 3D MRCPs on a 1.5-T system for pathologically confirmed IPMN were studied. Two-dimensional MRCP protocol included multiplanar thin- and thick-slab single-shot fast spin-echo imaging, coronal single-shot fast spin-echo, and transverse T2-weighted fast spin-echo imaging. Three-dimensional MRCP was performed using a fast-recovery fast spin-echo sequence with single-volume acquisition and maximum intensity projection reconstructions. Using a 5-point scale, 2 readers independently evaluated MRCPs for (1) image quality, (2) visualization of the pancreatic duct (PD), and (3) visualization of the cystic lesions. Intraductal papillary mucinous neoplasm's morphological features (septa, mural nodules, and duct communication) were also graded similarly to predict benignity or malignancy. Surgical and pathological data served as reference standard. A pancreatic surgeon reviewed the 21 MRCPs to determine the usefulness of 3D MRCP compared with that of 2D MRCP for surgical planning. Of the 21 IPMNs, 11 were side-branch IPMNs and 10 were main-duct-lesions IPMNs with side-branch involvement. A statistically significant improvement in image quality and visualization of the PD and cystic lesion was demonstrated with 3D MRCP in comparison with that demonstrated with 2D MRCP (P < or = 0.002). The morphological details of IPMN were also identified, with higher confidence with 3D MRCP in comparison with that using 2D MRCP. Two-dimensional and 3D MRCPs performed similarly for predicting benign and malignant lesions, with sensitivity ranging from 50.0% to 66.7% and specificity ranging from 86.7% to 93.3%. The pancreatic surgeon preferred 3D to 2D MRCP for surgical evaluation and planning in 14 of 21 cases. Compared with 2D MRCP, 3D MRCP provides better image quality, offers superior evaluation of the PD and morphological details of IPMN, and is preferred for surgical planning.

967 Main-Duct and Combined IPMNs Are the Same Clinical Entity and Distinct from Branch-Duct IPMNs

G A A b st ra ct s reported abdominal complaints as opposed to 7.6% of those without PC(s) (p = 0.589). None of the individuals with PC(s) had pancreatic disease in their medical history. Conclusion: In individuals undergoing preventive medical examination with MRI, the prevalence of PCs was 2.2%. Of these PCs, 5.3% were ≥30 mm, 8% were multilocular and in 10% of cases may represent side-branch IPMN. Cyst presence correlated with increasing age, no difference of prevalence by sex was found. Abdominal complaints did not correlate with PC presence.

Direct Visualization of the Wall of Pancreatic Cysts Using the SPYGLASS Optical Probe: Feasibility and Preliminary Results

Background: Accurate risk stratification of pancreatic cystic lesions (PCL) is important in determining the risk/benefit of resection, particularly in pts at increased surgical risk due to advanced age and comorbidities. The current approach utilizing multiple diagnostic modalities is limited. Review of surgical specimens from resected pancreatic cystic neoplasms shows characteristic morphology of the interior of these lesions, with “sponge-like” microcystic areas in serous cystadenomas, smooth pale walls with adherent mucin in mucinous lesions and side-branch orifices in side-branch IPMN. We considered the idea that in-vivo examination of the interior of a cyst with a fiberoptic probe could help classify PCLs and possibly detect small neoplastic mural lesions not seen by EUS. Methods: We used a 0.77 mm optical probe (SpyGlass, Boston Scientific) introduced via 19 Ga needle (Echotip, Wilson-Cook). The needle was inserted into the cyst under EUS. The cyst fluid was aspirated completely and the fluid sent for analysis. Saline was infused into the cyst, repeated until the aspirate was clear. The following data were collected: technical success, duration, image quality (poor, adequate, excellent), wall morphology, fluid characteristics, and complications. Results: 5 pts (three men), of median age 78 (77-85) with one pancreatic cyst each were included in the study. Two cysts were in the head, one in the body, and one in the tail of the pancreas. The median diameter of the cysts was 25 mm (17-50). The mean duration of the Spyglass examination was 11 min (6-16). Image quality was poor in 1, adequate in 2 and excellent in 2 examinations. The optical probe detected lesions not seen by EUS in 2 of the 5 pts. In Pt 1 a small yellow nodule was seen on the posterior cyst wall covered with mucin, not visible on CT or previous EUS, on which we performed FNA. Cytology revealed carcinoma, surgical pathology showed IPMN with CIS, with a focus of microinvasion. In Pt 2 the optical probe showed a tan polypoid lesion arising from an otherwise smooth pale wall of the cyst. Cytology revealed reactive epithelial cells staining for CEA. CEA 13,354, amylase 370. In Pts 3 and 4, the optical probe confirmed side-branch IPMN and, in Pt 5, pseudocyst. Conclusion. Our technique allows direct visualization of the interior of pancreatic cysts at the time of EUS/FNA and appears feasible in moderately sized cysts without densely stained fluid, located in the superior head, body and tail. Our results suggest a need to study the utility of this technique in detecting features that may help classify indeterminate cystic lesions and detect small high-grade mural lesions missed by EUS.