Predictors of Malignancy in “Pure” Branch-Duct Intraductal Papillary Mucinous Neoplasm of the Pancreas without Enhancing Mural Nodules on CT Imaging: A Nationwide Multicenter Study

BACKGROUND/AIMS: Presence of enhanced mural nodules, which can be visualized using computed tomography (CT), is one of high-risk stigmata in branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs). Conversely, the absence of enhanced mural nodules on preoperative imaging does not exclude malignant risk. The present study aimed to investigate other morphological features as predictors of malignancy in “pure” BD-IPMNs without enhanced mural nodules on CT. METHODS: This retrospective study included 180 patients with surgically confirmed “pure” BD-IPMNs of the pancreas and no enhanced mural nodules on preoperative CT. The study was conducted at 15 tertiary referral centers throughout South Korea. Univariate and multivariate analyses were used to identify significant predictors of malignancy. RESULTS: BD-IPMNs with low-grade (n=84) or moderate-grade (n=76) dysplasia were classified as benign; those with high-grade dysplasia (n=8) or invasive carcinoma (n=12) were classified as malignant. The multivariate analysis revealed that cyst size ≥30 mm (odds ratio, 8.6; p=0.001) and main pancreatic duct diameter ≥5 mm (odds ratio, 4.1; p=0.01) were independent risk factors for malignancy in “pure” BD-IPMNs without enhanced mural nodules on CT. Endoscopic ultrasound detected enhanced mural nodules (6/82) that had been missed on CT, and two IPMNs with enhanced mural nodules were malignant. CONCLUSIONS: In patients with “pure” BD-IPMNs who have no enhanced mural nodules on CT, cyst size ≥30 mm and main pancreatic duct diameter ≥5 mm may be associated with malignancy.

Grave Clinical Course of Pancreatic Invasive Cancer Developed in the Patients with Branch Duct IPMN: A Report of Three Cases / 대한췌담도학회지

Branch duct intraductal papillary mucinous neoplasms of the pancreas (BD-IPMN) without malignant features rarely developed into invasive cancer. However, invasive cancer is aggressive once an invasive change occurs. We report three cases of invasive cancers which developed in patients with BD-IPMN and they showed grave clinical courses. All patients were diagnosed with BD-IPMN < 3 cm without malignant features on imaging. Invasive cancer was detected at 2.5 years, 3.0 years, and 4.0 years after BD-IPMN detection in each patient. The intervals of invasive cancer and the last follow-up were 9 months, 3 years, and 1.5 years in the three patients, respectively. All patients were diagnosed with locally advanced pancreas invasive cancers and were treated with palliative chemotherapy or conservative management. The patients died at 3 months, 9 months, and 10 months after the diagnosis of invasive cancers, respectively. We report three cases of invasive cancer developed in BD-IPMN patients and followed fatal courses.

Branch duct intraductal papillary mucinous neoplasm of the pancreas: single-center experience with 324 patients who underwent surgical resection

BACKGROUNDS/AIMS: International treatment guidelines for branch duct intraductal papillary mucinous neoplasm (BD-IPMN) of the pancreas have been proposed, for features associated with malignancy and invasiveness. We investigated the clinicopathological characteristics that are predictive of malignancy or invasiveness and disease recurrence. METHODS: A review of 324 patients with resected and pathologically confirmed BD-IPMN, between March 1997 and December 2013, was conducted. RESULTS: There were 144 (44.4%) low grade dysplasia (LGD), 138 (42.6%) intermediate grade dysplasia (IMGD), 17 (5.3%) high grade dysplasia (HGD), and 25 (7.7%) invasive carcinoma (invIPMC) cases. The 5-year survival rates were 98.1% for LGD, 95.3% for IMGD, 100% for HGD, and 71.8% for invIPMC. Through a univariate analysis, the male sex was associated with malignancy, and CA19-9 was related to both malignant and invasive IPMN. The high risk or worrisome features of the international guidelines were associated with both malignant and invasive IPMN: the total bilirubin of the head/uncinate lesion, tumor size, mural nodule, and the size of the main pancreatic duct (MPD). Through a multivariate analysis, the male sex, elevated CA19-9, mural nodule, and dilated MPD diameter were independently correlated with the malignant IPMN. The elevated CA19-9 and dilated MPD diameter were also correlated with invasive carcinoma. The patient age and the initial pathological diagnosis were strongly associated with disease recurrence following surgical resection. CONCLUSIONS: The high risk or worrisome features in the current treatment guidelines for BD-IPMN are confined to the morphological characteristics of the disease. Patient factors and biological features should also be considered in order to develop optimal therapeutic or surveillance strategies.

Surgical outcomes of multifocal branch duct intraductal papillary mucinous neoplasms of pancreas

BACKGROUNDS/AIMS: Appropriate management for multifocal branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) of the pancreas is still controversial. This study was intended to reveal surgical outcomes of surgical resection for multifocal BD-IPMNs, with BD-IPMNs in the remnant pancreas. METHODS: Between January 1995 and December 2013, 699 patients underwent the pancreatic resection due to IPMN of pancreas in our institution. Among them, 37 patients showed multifocal BD-IPMNs. After excluding patients who had BD-IPMNs completely resected, medical records of 22 patients with remained BD-IPMNs in the remnant pancreas were retrospectively reviewed. RESULTS: Mean patient age was 65+/-6.4 years. Types of surgery included central pancreatectomy (n=1), distal pancreatectomy (n=14), and standard pylorus-preserving pancreaticoduodenectomy (n=7). Specimen pathology showed that IPMN was either at low/intermediate-grade dysplasia (n=17) or at high-grade dysplasia (n=2). Three patients had IPMN associated with invasive carcinoma. Their mean follow-up period was 40.4 months. During follow-up, one mortality occurred 35.2 months after the operation which was not associated with IPMN. There was no clinically significant disease progression or recurrence of IPMN in the remnant pancreas during the follow-up period. CONCLUSIONS: Our results support that we can safely preserve the pancreas parenchyma with multifocal BD-IPMNs. Benign-looking multifocal BD-IPMNs in the remnant pancreas do not affect the survival of patients.

Determination of Malignant and Invasive Predictors in Branch Duct Type Intraductal Papillary Mucinous Neoplasms of the Pancreas: A Suggested Scoring Formula

Prediction of malignancy or invasiveness of branch duct type intraductal papillary mucinous neoplasm (Br-IPMN) is difficult, and proper treatment strategy has not been well established. The authors investigated the characteristics of Br-IPMN and explored its malignancy or invasiveness predicting factors to suggest a scoring formula for predicting pathologic results. From 1994 to 2008, 237 patients who were diagnosed as Br-IPMN at 11 tertiary referral centers in Korea were retrospectively reviewed. The patients' mean age was 63.1 +/- 9.2 yr. One hundred ninty-eight (83.5%) patients had nonmalignant IPMN (81 adenoma, 117 borderline atypia), and 39 (16.5%) had malignant IPMN (13 carcinoma in situ, 26 invasive carcinoma). Cyst size and mural nodule were malignancy determining factors by multivariate analysis. Elevated CEA, cyst size and mural nodule were factors determining invasiveness by multivariate analysis. Using the regression coefficient for significant predictors on multivariate analysis, we constructed a malignancy-predicting scoring formula: 22.4 (mural nodule [0 or 1]) + 0.5 (cyst size [mm]). In invasive IPMN, the formula was expressed as invasiveness-predicting score = 36.6 (mural nodule [0 or 1]) + 32.2 (elevated serum CEA [0 or 1]) + 0.6 (cyst size [mm]). Here we present a scoring formula for prediction of malignancy or invasiveness of Br-IPMN which can be used to determine a proper treatment strategy.

Determination of Malignancy Predictors in Branch Duct TypeIntraductal Papillary Mucinous Neoplasms of the Pancreas

PURPOSE: Branch duct type intraductal papillary mucinous neoplasms (Br-IPMN) have better prognosis and lower malignancy rate than do main duct type IPMNs (M-IPMN). However, surgical resection is necessary when malignancy is suspected, and radical resection should be performed in cases of invasive IPMN. The objectives of this study were to investigate the characteristics of Br-IPMN and related predictive malignancy/invasiveness factors and to present a standardized scoring system for predicting pathologic results. METHODS: We conducted a retrospective review of 91 patients diagnosed with Br-IPMNs between 1998 and 2007. Mean patient age was 62.5+/-9.0 years. Eighty (87.9%) patients had benign IPMNs (17 adenoma, 63 borderline malignancy), and 11 (12.1%) patients had malignant IPMNs (4 carcinoma in situ, 7 invasive carcinoma). Eighty-four (92.3%) patients had noninvasive IPMN, and 7 (7.7%) patients had invasive IPMN. RESULTS: The size of the cystic mass and the presence and size of the mural nodule were found by univariate analysis to be significantly different between the benign and malignant groups. History of DM, size of the cystic mass, size of the mural nodule, and thickness of the cystic wall were significantly different between the noninvasive and invasive IPMN groups on univariate analysis. The regression coefficients for the size of the cystic mass and for the size and presence of the mural nodule were calculated using multivariate analysis, and the scores predicting malignant and invasive IPMN determined (P=0.001, P=0.000, respectively). CONCLUSION: There are no universally held guidelines for surgical management of Br-IPMN patients. Hence, many clinicians have difficulty deciding the specific character of the resection they will pursue. By using malignancy- and invasiveness-predicting scores, we expect that much of this difficulty can be avoided in the future.

Surgical Management for Intraductal Papillary Mucinous Tumor (IPMT) of the Pancreas Confined to Branch Duct

PURPOSE: Intraductal papillary mucinous tumor (IPMT) of the branch duct type has been reported that it is associated with less aggressive histologic features than the main duct type. The purpose of this study was to evaluate the clinicopathologic features and the optimal management of branch duct type IPMT. METHODS: From October 1994 to November 2004, 30 cases who underwent operations with branch duct type IPMT were reviewed retrospectively. Clinicopathologic findings and late results of treatment were studied in 20 cases of the benign (adenoma, borderline malignancy) group and in 10 cases of the malignant (carcinoma in situ, invasive carcinoma) group. RESULTS: There were statistically significant difference in the 3 factors (mural nodule (P=0.030), diameter of the main pancreatic duct (P=0.036), main location of the tumor (P= 0.031)). There was no statistically significant difference in th survival analysis between the main duct type IPMT including combined type IPMT and the branch duct type IPMT (P=0.572), but there was significant difference between the benign group and the malignant group of the branch duct type IPMT (P=0.049). CONCLUSION: The long-term follow up result of the branch duct type IPMT is similar to that of the main and combined duct type IPMT. Therefore, it is not safe just to monitor the branch duct type IPMT. Our results suggest that surgery is certainly the gold standard treatment for the branch duct type IPMT. And after operation, close long term follow up with appropriate treatment is necessary due to tumor recurrence.