CLINICAL SIGNIFICANCE OF INTRADUCTAL ULTRASONOGRAPHY FOR DIAGNOSIS OF INTRADUCTAL PAPILLARY MUCINOUS NEOPLASM OF THE PANCREAS

Intraductal ultrasonography (IDUS) is useful for evaluating the horizontal spread along the main pancreatic duct in cases of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, thus providing valuable information for the determination of the resection line at surgery. Differentiation between benign and malignant IPMN is also indispensable for management decisions. Measurement of the height of mural nodules by IDUS is expected to be useful for differential diagnosis of IPMN. Because IDUS cannot always demonstrate whole lesions, especially in branch duct IPMN, endoscopic ultrasonography plays a complementary role in such cases.     

MANAGEMENT OF INTRADUCTAL PAPILLARY MUCINOUS NEOPLASM OF THE PANCREAS

Intraductal papillary mucinous neoplasms of the pancreas (IPMNs) consist of main duct (MD) type and branch duct (BD) type. The authors describe their way of thinking regarding diagnostic modalities and management for BD type IPMNs. Endoscopic ultrasonography (EUS) and intraductal ultrasonography (IDUS) provide high resolution images of main and branch pancreatic ducts. The cases with nodules demonstrated by EUS and/or IDUS regardless of the size are the indication of operation. There were 235 cases with BD type IPMN who underwent EUS and IDUS between April 1991 and June 2005. A total of 94 patients underwent surgical resection and were histopathologically diagnosed (carcinoma, 10 cases; adenoma, 64 cases; hyperplasia, 20 cases). Diagnoses of 79 cases with nodules detected by EUS or IDUS preoperatively were 10 carcinomas, 61 adenomas and eight hyperplasias. Diagnoses of 15 cases without nodules but with symptoms were three adenomas, 12 hyperplasias and no carcinoma. The authors think that the combination of EUS and IDUS is the best way for diagnosing BD type IPMNs in the present state.     

PERORAL PANCREATOSCOPY AND INTRADUCTAL ULTRASONOGRAPHY IN DETERMINING THE RESECTION LINES OF INTRADUCTAL PAPILLARY MUCINOUS TUMORS OF THE PANCREAS

In patients with malignant intraductal papillary–mucinous tumors (IPMT), the tumor spread along the main pancreatic duct is generally inspected as mural nodules within the ducts by peroral pancreatoscopy (POPS). Even the lower mural nodules including fish‐eggs‐like lesions and granular mucosa continued to the main taller mural nodules should be resected. Mural nodules along the main duct and cystic dilation of the branch ducts observed by intraductal ultrasonography (IDUS) are regarded as the tumor spread. Although POPS is superior to IDUS in identifying mural nodules along the main duct, POPS has limitations to detect mural nodules within the branch ducts. Therefore, the accuracy of the diagnosis by POPS is higher in main duct IPMT, whereas that by IDUS is higher in branch duct IPMT. These modalities should be performed as complementary tests in determining the resection lines preoperatively.     

LATERAL SPREAD ALONG THE MAIN PANCREATIC DUCT IN BRANCH‐DUCT INTRADUCTAL PAPILLARY‐MUCINOUS NEOPLASMS OF THE PANCREAS: USEFULNESS OF INTRADUCTAL ULTRASONOGRAPHY FOR ITS EVALUATION

Background: Intraductal papillary mucinous neoplasms (IPMN) of the pancreas tend to spread intraepithelially along the pancreatic duct wall. We evaluated histopathological intraductal lateral spread (LS) along the main pancreatic duct (MPD) from branch‐duct IPMN and investigated the usefulness of intraductal ultrasonography (IDUS) for its preoperative diagnosis. Patients and Methods: Twenty‐four patients with branch‐duct IPMN who had undergone preoperative IDUS and surgery were reviewed clinicopathologically. The prevalence and histological length of LS along the MPD from branch‐duct IPMN, characteristics of the patients with LS, and efficacy of LS assessment by IDUS were examined. Results: LS along the MPD was observed in 54% of the subjects. In the group of patients with LS, its mean length was 25.2 ± 16.8 mm (5–50 mm) and the diameter of the MPD was 6 mm or greater. Of the patients with LS, those in whom the length of LS along the MPD was longer than the diameter of the cystically dilated branch accounted for 30%. The diameter of the MPD in the group with LS was significantly greater than that in the group without LS (P = 0.03). The sensitivity, specificity, and overall accuracy of IDUS in the detection of LS were 92%, 91%, and 92%, respectively. Conclusion: LS along the MPD was detected in about half of the resected cases of branch‐duct IPMN. Preoperative transpapillary IDUS may be beneficial for the determination of the resection line, especially in those branch‐duct IPMN patients in whom the MPD is 6 mm or greater in diameter.     

IDUS IN THE DIAGNOSIS OF IPMT

Intraductal papillary mucinous tumor of the pancreas (IPMT) is considered as having low‐grade malignant potential, and malignancy is not infrequent. Therefore, accurate diagnosis is indispensable for appropriate patient care. IPMT is classified mainly into two categories based on the distribution of tumor, the main duct type and the branch duct type. In the diagnosis of IPMT, there are four important points: differentiation of IPMT from other pancreatic pathologies; differentiation of malignancy from benign lesions; evaluation of tumor extent along the MPD; and investigation of duct cell carcinoma coexistent with or derived from IPMT. IPMT should be distinguished from chronic pancreatitis, ductal adenocarcinoma, or cystic neoplasms. IPMT often requires pancreaticoduodenectomy for cure, but such invasive surgery should be avoided in patients with benign hyperplasia. Mural nodules in the MPD can be clearly visualized by intraductal ultrasonography (IDUS). Measurement of the height of the tumor mass by IDUS is useful in distinguishing benign from malignant IPMT. Intraductal spread of IPMT along the MPD is demonstrated by IDUS as irregular thickening of the MPD wall. To achieve a tumor‐free margin in surgery, evaluation by IDUS of the extent of the tumor along the MPD is important. The expected accuracy of IDUS in the diagnosis of invasive IPMT is reportedly over 90%.     

Endoscopic diagnosis of cystic lesions of the pancreas

Endoscopic methods are increasingly used in the diagnosis of cystic lesions of the pancreas. The two major endoscopic approaches are endoscopic ultrasonography (EUS) and transpapillary diagnosis. EUS‐guided fine‐needle aspiration cytology and EUS‐guided fine needle‐based confocal laser endomicroscopy have been used in the differential diagnosis of mucinous and non‐mucinous pancreatic cysts. EUS is the most sensitive modality for detecting mural nodules (MN) in intraductal papillary mucinous neoplasms (IPMN). Contrast‐enhanced harmonic EUS (CH‐EUS), as an add‐on to EUS, is useful for identifying and characterizing MN. Recent studies show that CH‐EUS has a sensitivity of 60–100% and a specificity of 75–92.9% for diagnosing malignant cysts. Intraductal ultrasonography and peroral pancreatoscopy are especially useful for detecting MN and IPMN. A recent meta‐analysis showed that cytological assessment of pancreatic juice using a transpapillary approach had a pooled sensitivity, specificity, and accuracy of 35.1%, 97.2%, and 92.9%, respectively, for diagnosing malignant IPMN. Further studies are warranted to determine the indications for each of these novel techniques in assessing cystic lesions of the pancreas.     

Preoperative diagnosis of bile duct strictures--comparison of intraductal ultrasonography with conventional endosonography

BACKGROUND: The accuracy of intraductal ultrasonography (IDUS) and endoscopic ultrasonography (EUS) were compared in diagnosing biliary obstruction and in predicting surgical resectability. METHODS: Fifty-six patients with biliary obstruction were investigated preoperatively with both conventional EUS and IDUS. The ultrasonographic miniprobe was inserted into the bile duct system through the working channel of the duodenoscope during endoscopic retrograde cholangiopancreatography (ERCP). Conventional endosonography was performed with echoendoscopes in a standard technique. Images of endoluminal ultrasonography were prospectively reviewed and compared with intraoperative findings and resection specimen analyses. RESULTS: IDUS exceeded EUS in terms of accuracy (IDUS, 89.1%; EUS, 75.6%; P < 0.002), sensitivity (IDUS, 91.1%; EUS, 75.7%; P < 0.002), specificity (IDUS, 80%; EUS, 75%; NS), and T-staging (IDUS, 77.7%; EUS, 54.1%; P < 0.001). In bile duct carcinomas the accuracy rate for lymph node staging using IDUS (60%) is comparable with that using EUS (62.5%). In pancreatic carcinomas, however, lymph node staging using IDUS (13.3%) is significantly (P < 0.002) inferior to EUS (69.2%). Endoluminal ultrasonography may predict the potential resectability of bile duct tumors (IDUS, 81.8%; EUS, 75.6%; P < 0.002). CONCLUSIONS: IDUS proved to be accurate in preoperative diagnosing and T-staging of malignant biliary strictures, whereas it is not suitable for lymph node staging. IDUS using miniprobes during ERCP exceeds conventional EUS in terms of depiction of bile duct obstruction, diagnostic accuracy, and sensitivity and in the prediction of surgical tumor resectability. Additionally, different to EUS, IDUS can conveniently be performed during ERCP in one and the same session.     

Small invasive ductal carcinoma of the pancreas distinct from branch duct intraductal papillary mucinous neoplasm

Endoscopic ultrasonography (EUS) is a highly sensitive diagnostic method for the detection of small pancreatic carcinomas.Recently, there have been some reports describing the utility of contrast-enhanced harmonic EUS (CEH-EUS) which uses sonographic contrast agent for differentiation of a pancreatic mass.This report describes a case of small adenocarcinoma of the pancreas distinct from branch duct intraductal papillary mucinous neoplasm (IPMN) in which investigation by EUS took place every 6 mo and diagnosis was made accurately by additional CEH-EUS during the followup of the branch duct IPMN.A 68-year-old female was admitted to our hospital because of a branch duct IPMN in the pancreatic body.She had been followedup by EUS every 6 mo.However, after 2 years EUS demonstrated a low echoic area distinct from the branch duct IPMN which was vaguely discernible by EUS, and accurate sizing and differential diagnosis were considered difficult on the EUS imaging.CHEUS with Sonazoid revealed a hypovascular tumor and we suspected small pancreatic carcinoma.The histopathological diagnosis was adenocarcinoma (10 mm) in the pancreatic tail, distinct from the branch duct IPMN of the pancreatic body.EUS and CEH-EUS may play an important role in the correct diagnosis of small pancreatic tumors, including synchronous and metachronous occurrence of IPMN and ductal adenocarcinoma of the pancreas.     

Clinicopathological features and medical management of intraductal papillary mucinous neoplasms

BACKGROUND: Intraductal papillary mucinous neoplasms (IPMN) are a clinicopathological entity that is being diagnosed with increasing frequency. However, the best approach to medical management of IPMN needs to be clarified. The aim of the present study was to identify preoperative features that may be predictors of malignant IPMN, and to define the medical management of IPMN of the pancreas. METHODS: A total of 23 patients who underwent surgical resection for IPMN of the pancreas at Kochi Medical School between 1982 and 2004 were examined. Multivariate Cox regression analysis was used to identify factors independently associated with IPM carcinoma. RESULTS: Among the 23 patients, 12 had IPMN adenoma, three had borderline IPMN, four had IPMN with carcinoma in situ, and four had IPMN with invasive carcinoma. In multivariate analysis, elevated serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 levels were found to be preoperative predictors of malignant IPMN. These results suggest that the following IPMN of the pancreas should be resected: (i) IPMN of the pancreas situated in the main duct; (ii) IPMN located in the branch duct if the size of the cystic lesion is >30 mm and the mural nodules are >5 mm in height by endoscopic ultrasound (EUS); and (iii) the diameter of the main pancreatic duct is >10 mm by endoscopic retrograde pancreatography (ERP). Careful observation of patients with branch-type IPMN with small cysts and/or without mural nodules is recommended as a management strategy. CONCLUSION: The present study reinforces the need for immediate surgical resection of malignant IPMN and suggests indicators for IPMN that should assist physicians in making decisions on treatment options.     

Intraductal papillary mucinous neoplasm of the pancreas: diagnosis and treatment

Intraductal papillary mucinous neoplasm (IPMN) is characterized by cystic dilatation of the main and/or branch pancreatic duct. Only one-third of all patients are symptomatic, and others are diagnosed by chance. IPMNs are classified into 3 types: main duct, branch duct, and mixed IPMN. Most branch-type IPMNs are benign, while the other 2 types are frequently malignant. The presence of large mural nodules increases the possibility of malignancy in all types. Presence of a large branch-type IPMN and marked dilatation of the main duct indicate, at the very least, the existence of adenoma. Ultrasonography, endosonography, and intraductal ultrasonography clearly demonstrate ductal dilatation and mural nodules, and magnetic resonance pancreatography best visualizes the entire outline of IPMN. Not infrequently, synchronous or metachronous malignancy develops in various organs, including the pancreas. Prognosis is excellent after complete resection of benign and noninvasive malignant IPMNs. Asymptomatic branch-type IPMNs without mural nodules may be followed up without resection. Malignant IPMNs displaying acquired aggressiveness after parenchymal invasion require adequate lymph node dissection. Total pancreatectomy is needed for some IPMNs; its benefits, however, must be balanced against operative and postoperative risks because most IPMNs are slow growing and affect elderly people, and prognosis is favorable for IPMN patients with even malignant neoplasms.     

Preoperative Diagnosis of Bile Duct Strictures-Comparison of Intraductal Ultrasonography with Conventional Endosonography

Background: The accuracy of intraductal ultrasonography (IDUS) and endoscopic ultrasonography (EUS) were compared in diagnosing biliary obstruction and in predicting surgical resectability. Methods: Fifty-six patients with biliary obstruction were investigated preoperatively with both conventional EUS and IDUS. The ultrasonographic miniprobe was inserted into the bile duct system through the working channel of the duodenoscope during endoscopic retrograde cholangiopancreatography (ERCP). Conventional endosonography was performed with echoendoscopes in a standard technique. Images of endoluminal ultrasonography were prospectively reviewed and compared with intraoperative findings and resection specimen analyses. Results: IDUS exceeded EUS in terms of accuracy (IDUS, 89.1%; EUS, 75.6%; P &lt; 0.002), sensitivity (IDUS, 91.1%; EUS, 75.7%; P &lt; 0.002), specificity (IDUS, 80%; EUS, 75%; NS), and T-staging (IDUS, 77.7%; EUS, 54.1%; P &lt; 0.001). In bile duct carcinomas the accuracy rate for lymph node staging using IDUS (60%) is comparable with that using EUS (62.5%). In pancreatic carcinomas, however, lymph node staging using IDUS (13.3%) is significantly (P &lt; 0.002) inferior to EUS (69.2%). Endoluminal ultrasonography may predict the potential resectability of bile duct tumors (IDUS, 81.8%; EUS, 75.6%; P &lt; 0.002). Conclusions: IDUS proved to be accurate in preoperative diagnosing and T-staging of malignant biliary strictures, whereas it is not suitable for lymph node staging. IDUS using miniprobes during ERCP exceeds conventional EUS in terms of depiction of bile duct obstruction, diagnostic accuracy, and sensitivity and in the prediction of surgical tumor resectability. Additionally, different to EUS, IDUS can conveniently be performed during ERCP in one and the same session.     

Contrast-enhanced endoscopic ultrasonography improves the preoperative localization of insulinomas

We report a case in which endoscopic ultrasonography (EUS), intraductal ultrasonography (IDUS) and contrast-enhanced EUS using Levovist helped to localize insulinoma correctly. A 74-year-old woman complained of symptomatic fasting hypoglycemia with relatively high concentration of serum insulin level. Dynamic contrast-enhanced computed tomography revealed a small tumor of 8 mm diameter in the pancreatic head. Insulin secretion was strongly stimulated by calcium injection into the gastroduodenal artery. To clarify the precise localization, we performed EUS, IDUS and contrast-enhanced EUS. The tumor was enhanced clearly by Levovist, and the distance from the main pancreatic duct was more than 3 mm. Therefore, a preoperative decision could be made to use the enucleation method for resection of the tumor. The surgeon could enucleate the tumor in a brief operation according to the preoperative diagnosis, and serum glucose levels returned to normal range after the operation. Contrast-enhanced EUS using Levovist was shown to be a useful diagnostic method for precise localization of small insulinoma.     

Endoluminal ultrasonography for pancreatic diseases.

Endoluminal ultrasonography was performed on 146 patients with pancreatobiliary diseases by using high-frequency, thin ultrasonic probes, and the usefulness of the new technique in diagnosis of pancreatic diseases was reported. The ultrasound probe could be inserted into the main pancreatic duct in 43 of 46 patients (93.5%), and images of the lesions could be obtained in 42 patients (91.3%). Endoluminal ultrasonography revealed a hypoechoic mass with clear margins and central echogenicity in patients with pancreatic carcinoma. Endoluminal ultrasonography showed normal pancreatic parenchyma as a fine reticular pattern and did not reveal the tumors surrounding the stenosis in patients with focal pancreatitis. Endoluminal ultrasonography in patients with intraductal papillary adenocarcinoma of the pancreas revealed cystic lesions with mural nodules more than 4 mm, mucus echoes, and solid tumors with mixed echo patterns. There were no severe complications, and acute pancreatitis occurred in none of 46 patients, but high-level serum amylase after examination occurred in 5 patients (10.9%). Endoluminal ultrasonography is useful for differential diagnosis in patients with small pancreatic tumors or cystic lesions, especially intraductal papillary tumors of the pancreas. Endoluminal ultrasonography is recommended as a precise examination for the diagnosis of cystic lesions of the pancreas or stenosis of the main pancreatic duct after ERCP and EUS.     

Management of intraductal papillary-mucinous neoplasm of the pancreas: treatment strategy based on morphologic classification

GOALS: The aim of this study was to examine and clarify the preoperative markers that are useful for differentiating between benign and malignant lesions of intraductal papillary-mucinous neoplasms (IPMN) of the pancreas, grouped according to morphologic classification. BACKGROUND: There are various stages of pathology in IPMN, ranging from benign to malignant lesions. Although the determination of appropriate treatment guidelines to deal with IPMN is a critical issue, no such guidelines have been established. PATIENTS AND METHODS: One hundred twenty cases of IPMN were classified morphologically into either main or branch duct types. We compared the morphologic classification with histopathologic diagnosis using indicators of malignancy detected by imaging such as main duct diameter, the number and diameter of cysts, and the presence or absence of mural nodules. We also examined the usefulness of pancreatic juice cytology and measurement of telomerase activity as indicators of malignancy. Finally, we performed a survival analysis on the basis of morphologic classification to determine prognosis of IPMN. RESULTS: Whereas a high incidence (64%) of malignant lesions was seen in main duct type IPMN, benign lesions were dominant (80.5%) in branch duct type IPMN. Survival analysis showed that the prognosis was significantly worse in main duct type than in branch duct type IPMN. The lesions were aggravated in all patients with main duct type who did not undergo resection, resulting in death due to progression of the pancreatic lesion. The incidence of mural nodules was a useful indicator in main duct type, whereas main duct diameter and incidence of mural nodules were useful indicators in branch duct type. Although pancreatic juice cytology showed a high accuracy rate with low sensitivity for determining malignancy, measurement of telomerase activity in this juice was very effective for differentiating between benign and malignant lesions. CONCLUSIONS: The incidence of malignant lesions was extremely high in main duct type IPMN, indicating that surgery is required in all these patients. However, to determine whether surgery is indicated in branch duct type IPMN it is necessary to obtain an appropriate image diagnosis focusing on main duct diameter and mural nodules and also to carry out cytology and measurement of telomerase activity in samples of pancreatic juice.     

Differential diagnosis of benign and malignant branch duct intraductal papillary mucinous neoplasm using contrast-enhanced endoscopic ultrasonography

AIM: To elucidate the role of contrast-enhanced endoscopic ultrasonography (CE-EUS) in the diagnosis of branch duct intraductal papillary mucinous neoplasm (BD-IPMN).METHODS: A total of 50 patients diagnosed with BD-IPMN by computed tomography (CT) and endoscopic ultrasonography (EUS) at our institute were included in this study. CE-EUS was performed when mural lesions were detected by EUS. The diagnostic accuracy for identifying mural nodules (MNs) was evaluated by CT, EUS, and EUS combined with CE-EUS. In the patients who underwent resection, the accuracy of measuring MN height with each imaging modality was compared. The cut-off values to diagnose malignant BD-IPMNs based on MN height for each imaging modality were determined using receiver operating characteristic curve analysis.RESULTS: Fifteen patients were diagnosed with BD-IPMN with MNs and underwent resection. The remaining 35 patients were diagnosed with BD-IPMN without MNs and underwent follow-up monitoring. The pathological findings revealed 14 cases with MNs and one case without. The accuracy for diagnosing MNs was 92% using CT and 72% using EUS; the diagnostic accuracy increased to 98% when EUS and CE-EUS were combined. The accuracy for measuring MN height significantly improved when using CE-EUS compared with using CT or EUS (median measurement error value, CT: 3.3 mm vs CE-EUS: 0.6 mm, P < 0.05; EUS: 2.1 mm vs CE-EUS: 0.6 mm, P < 0.01). A cut-off value of 8.8 mm for MN height as measured by CE-EUS improved the accuracy of diagnosing malignant BD-IPMN to 93%.CONCLUSION: Using CE-EUS to measure MN height provides a highly accurate method for differentiating benign from malignant BD-IPMN.     

Endoscopic ultrasonographic findings predict the risk of carcinoma in branch duct intraductal papillary mucinous neoplasms of the pancreas

BackgroundThe preoperative diagnosis of branch duct intraductal papillary mucinous neoplasm (IPMN) of the pancreas can be very difficult, since low-risk and high-risk lesions can be difficult to differentiate even after cytological analysis. The purpose of this study was to evaluate the preoperative diagnostic value of endoscopic ultrasonography (EUS) in differentiating low-risk and high-risk IPMNs.MethodsWe retrospectively identified 36 patients who underwent preoperative EUS for branch duct IPMNs. The pathological diagnosis after surgical resection was low-grade dysplasia (n = 26), moderate dysplasia (n = 1), high-grade dysplasia or carcinoma in situ (n = 5), and invasive carcinoma (n = 4). We divided the patients into two groups: low risk (low-grade dysplasia or moderate dysplasia) and high risk (high-grade dysplasia or carcinoma). We focused on the diameter of the cystic dilated branch duct, the main pancreatic duct, and the mural nodule as measured using the EUS findings.ResultsThe cystic dilated branch duct diameter (31.5 mm vs. 41.9 mm, P = 0.0225) was significantly correlated with low-risk and high-risk IPMNs, but the main pancreatic duct diameter (5.37 mm vs. 5.44 mm, P = 0.9418) was not significantly correlated with the low-risk and high-risk IPMNs. The mural nodule diameter of the papillary protrusions (4.3 mm vs. 16.4 mm, P < 0.0001) and the width diameter of the mural nodule (5.7 mm vs. 23.2 mm, P < 0.0001) were significantly correlated with low-risk and high-risk IPMNs.ConclusionsThe mural nodule of papillary protrusions diameter and width diameter observed using EUS was a reliable preoperative diagnostic finding capable of distinguishing low-risk and high-risk IPMNs.     

Differential diagnosis of intraductal papillary‐mucinous tumor of the pancreas by endoscopic ultrasonography and intraductal ultrasonography

Background: Intraductal papillary‐mucinous tumor (IPMT) of the pancreas has a broad spectrum of histology ranging from hyperplasia to adenocarcinoma. Therefore, it is important to differentiate between the malignant and benign lesions to determine the therapeutic strategy for IPMT. Patients and Methods: Thirty‐nine patients with IPMT (27 men and 12 women, mean age: 63.3 years) underwent surgery between January 1985 and March 2002. The size of the cystic lesion, the maximum diameter of the main pancreatic duct (MPD), and the height of the papillary tumor inside the cyst were investigated by endoscopic ultrasonography (EUS) and/or intraductal ultrasonography (IDUS) before operation. These preoperative clinical findings were compared with the pathological findings of the resected specimen. Results: The size of the cystic lesion, the diameter of MPD, and the height of the papillary tumor in cases with malignant IPMT (invasive and non‐invasive carcinoma) were larger than those in cases with benign IPMT (adenoma and hyperplasia). Analysis of the images of the lesions revealed that the following three factors are important for diagnosing IPMT: (i) the size of the cystic lesion is ≥ 30 mm; (ii) the diameter of MPD is ≥ 8 mm; (iii) the height of the papillary tumor inside the cyst is ≥ 3 mm. It was not significant to differentiate between benign and malignant IPMT based on factor (i), but statistically significant (P < 0.001) based on factors (ii) and (iii). Conclusions: EUS and IDUS are useful in the differential diagnosis of IPMT, especially in the differentiation between malignant and benign IPMT.     

MANAGEMENT STRATEGIES FOR BRANCH DUCT INTRADUCTAL PAPILLARY‐MUCINOUS NEOPLASMS

Management strategies for branch duct intraductal papillary‐mucinous neoplasms (IPMN) have been discussed. The authors’ clinical criteria with special attention to the size of cystic lesion, the diameter of main pancreatic duct, and the size of mural nodule established in 2001 is useful for managing branch duct IPMN. A total of 55 of 60 cases with branch duct IPMN had no radiologic progression during an average follow up of 701 days. In addition, no case out of 27 cases with branch duct IPMN followed up for 3 years changed to positive in cytological examination using pancreatic juice. There were four cases of branch type IPMN with some changes in their image findings. There were two cases of branch type IPMN with pancreatic symptoms. A total of three out of these five cases were surgically resected. The ordinary‐type ductal carcinoma was detected in two cases with branch duct IPMN at 3 or 4 years later. These results suggest that a long‐term careful follow‐up study by computed tomography or ultrasonography at every 6 months would be needed in the management of branch duct IPMN. Further studies will be needed to dissolve this problem in the future.     

Size of mural nodule as an indicator of surgery for branch duct intraductal papillary mucinous neoplasm of the pancreas during follow-up

Background

A mural nodule is a strong predictive factor for malignancy in branch duct intraductal papillary mucinous neoplasm (IPMN) of the pancreas, but the nodule size has hardly been considered. The aim of this study was to investigate whether a mural nodule of 10?mm was appropriate as an indicator of surgery for IPMN during follow-up.

Methods

The follow-up outcomes of 100 patients who had branch duct IPMN without mural nodules or who had branch duct IPMN with mural nodules of less than 9?mm in a tertiary care setting were investigated retrospectively. The patients underwent abdominal ultrasound (US) every 3?months and additional imaging examinations or cytologic examination of pancreatic juice when necessary. Surgery was recommended to them when a mural nodule developed or when a nodule enlarged and reached 10?mm.

Results

During an average follow-up period of 97?months, branch duct IPMNs developed mural nodules that reached 10?mm in 5 patients (0.62% per year). In one patient the IPMN was revealed to be non-invasive carcinoma by resection, 1 IPMN was shown to be malignant by further follow-up, and 3 were not resected because of refusal or the patient??s age. In 7 patients, mural nodules stayed within 9?mm. The remaining 88 patients lacked mural nodules in their branch duct IPMNs throughout the follow-up. The occurrence of invasive carcinoma around the IPMN was not indicated by imaging examinations in any patient. Univariate analysis showed that the size of the cyst at baseline significantly predicted the development of a mural nodule that reached 10?mm during follow-up (P?=?0.05).

Conclusions

A mural nodule of 10?mm is appropriate as an indicator of surgery in the follow-up of branch duct IPMN.     

内镜诊治胰腺导管内乳头状粘液性肿瘤的应用

目的探讨胰腺导管内乳头状粘液性肿瘤(IPMN)的诊断、内镜下治疗,以提高对该疾病的认识及内镜对其诊断及治疗的意义。方法回顾性分析经内镜诊治的IPMN患者12例,总结并分析他们的一般情况、临床症状、影像学检查、实验室检查、内镜下治疗等方面资料。结果 12例IPMN患者以老年男性为主,无特异性临床表现,主要发生部位为胰头或钩突部,CT主要表现为囊实性低密度影,其内可有壁结节,胰管扩张伴或不伴胆管扩张,2例侵及胰腺实质。磁共振胰胆管造影(MRCP)主要表现为胰管扩张,胰腺萎缩,胰头部圆形高信号影。内镜下逆行胰胆管造影(ERCP)显示十二指肠乳头膨大,开口扩张,可见胶冻样粘液流出,胰管造影显示胰管全程扩张或胰头部囊状扩张,3例伴胆总管、肝内胆管扩张。9例行ERCP治疗,清除粘液栓并置入胰管支架,3例同时置入胆管支架。结论 IPMN是一种特殊类型的胰腺囊性疾病,影像学检查有其独特的表现,ERCP对其诊断及治疗有重要意义。