Rare condition of needle tract seeding after EUS-guided FNA for intraductal papillary mucinous carcinoma

Current status of endoscopic ultrasound in the diagnosis of intraductal papillary mucinous neoplasms

The new Kyoto guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) provide evidence-based recommendations for the diagnosis and treatment of IPMN. Endoscopic ultrasonography (EUS) is a diagnostic modality with a high spatial resolution that allows detailed observation and obtaining cyst fluid or tissue samples via EUS-guided fine needle aspiration (EUS-FNA). Currently, EUS is an indispensable examination method for the diagnosis of pancreatic diseases. On the other hand, there have been concerns that EUS imaging tends to be highly operator-dependent, and may lack objectivity. Previous guidelines have assigned EUS as an option for patients with worrisome features. However, recent reports indicate that the sensitivity of EUS for the diagnosis of mural nodules (MNs) is more than 90%, comparable or superior to that of contrast-enhanced computed tomography or magnetic resonance cholangiopancreatography. The specific advantages of EUS in the diagnosis of IPMN are: (1) high spatial resolution imaging for the diagnosis of MNs, (2) contrast-enhanced EUS for differentiation of intra-cystic MNs from mucous clots, and (3) pathological diagnosis using EUS-FNA and differential diagnosis of a pancreatic cystic tumor by cystic fluid analysis. In order to utilize EUS in the diagnosis of IPMN, endoscopists are required to have the skills to provide sufficiently objective imaging findings.

Needle-Tract Seeding of Pancreatic Cancer after EUS-FNA: A Systematic Review of Case Reports and Discussion of Management

Needle-tract seeding (NTS) has been sporadically reported as complication of Endoscopic Ultrasound (EUS)-guided aspiration (FNA) in pancreatic adenocarcinoma (PDAC). However, the evidence of its treatment and outcome is sparse. Adhering to PRISMA guidelines, we conducted a systematic review of EUS-FNA NTS cases of PDAC and analyzed their management and outcome. Up to September 2022, the search query retrieved forty-five cases plus an unpublished case from our center, for a total of forty-six; 43.6% were male, with a mean age of 68.6 years. Thirty-four patients (87.1%) underwent an initial surgical resection, with only 44.1% and 5.9% undergoing adjuvant and neoadjuvant chemotherapy, respectively, and 5.9% undergoing both. The NTS nodule was mostly located in the posterior gastric wall, developing at a median of 19 months after primary resection; 82.4% underwent surgical resection of the seeding, while for 17.6%, palliative chemotherapy treatment. Follow-up after NTS diagnosis and treatment was reported for only twenty-three patients: when NTS was treated with surgery, the median overall survival was 26.5 months compared to 15.5 if treated with radio/chemotherapy. NTS after EUS-FNA of PDAC occurs late and might be treated aggressively with good results. Interestingly, only a low number of patients developing NTS underwent chemotherapy for the primary cancer, suggesting its possible protective role.

Isolated Gastric Metastases of Pancreatic Ductal Adenocarcinoma following Radical Resection—Impact of Endosonography-Guided Fine Needle Aspiration Tract Seeding

Background: Endosonography-guided fine needle aspiration biopsy (EUS-FNA)-associated metachronous gastric seeding metastases (GSM) of pancreatic ductal adenocarcinoma (PDAC) represent a serious condition with insufficient evidence. Methods: Retrospective analysis of PDAC resections with a curative-intent, proven pathological diagnosis of PDAC, preoperative EUS-FNA and post-resection follow-up of at least 60 months. The systematic literature search of published data was used for the GSM growth evaluation using Pearson correlation and the linear regression analyses. Results: The inclusion criteria met 59/134 cases, 16 (27%) had retained needle tract (15 following distal pancreatectomy, 1 following pylorus-sparing head resection). In total, 3/16 cases (19%) developed identical solitary GSM (10–26th month following primary surgery) and were radically resected. A total of 30 published cases of PDAC GSM following EUS-FNA were identified. Lesion was resected in 20 distal pancreatectomy cases with complete information in 14 cases. A correlation between the metastasis size and time (r = 0.612) was proven. The regression coefficient b = 0.72 expresses the growth of 0.72 mm per month. Conclusions: The GSM represent a preventable and curable condition. A remarkably high number of GSM following EUS-FNA was identified, leading to follow-up recommendation of EUS-FNA sampled patients. Multimodal management (gastric resection, adjuvant chemotherapy) may prolong survival.

Factors associated with misdiagnosis of preoperative endoscopic ultrasound in patients with pancreatic cystic neoplasms undergoing surgical resection

PURPOSE

Pancreatic cystic lesions (PCLs) include various types of cysts. Accurate preoperative diagnosis is essential to avoid unnecessary surgery on benign cysts. In this study, we aimed to identify the factors associated with misdiagnosis in preoperative endoscopic ultrasound (EUS) imaging and clinicopathological findings for PCLs.

METHODS

This study included 302 surgically resected patients with PCLs who underwent preoperative EUS. The preoperative EUS findings were re-evaluated and compared with the pathological diagnosis. Additionally, the factors associated with misdiagnosis of PCLs were investigated by multivariate analysis.

RESULTS

The preoperative diagnoses of PCLs were intraductal papillary mucinous neoplasm (IPMN) in 213 patients (70.5%), mucinous cystic neoplasm (MCN) in 33 patients (10.9%), serous neoplasm (SN) in 7 patients (2.3%), cystic degeneration cyst of solid tumor in 46 patients (15.2%), and pancreatic cancer with cystic degeneration in three patients (1.0%). A discrepancy between preoperative and postoperative diagnosis was found in 47 patients (15.6%). Based on the pathological diagnosis, the sensitivity of preoperative EUS imaging was IPMN 97.6% (206/211), MCN 90.0% (18/19), cystic degeneration 87.1% (27/31), and SN 15.4% (2/13). Multivariate analysis revealed that main pancreatic duct (MPD) communication ( - ) (odds ratio (OR), 4.54; 95% confidence interval (CI) 1.29-15.9), honeycomb-like structure ( +) (OR, 14.7; 95% CI 2.61-83.3), and MPD size ≦ 2 mm (OR, 16.3; 95% CI 3.93-67.6) were independently associated with misdiagnosis.

CONCLUSION

For cases in which MCN and cystic degeneration of solid tumor are presumed based on preoperative EUS imaging and cases with PCLs with a honeycomb-like structure, diagnosis with multimodalities or fluid analysis with EUS-guided fine-needle aspiration should be considered.

Clinical dilemma of endoscopic ultrasound-guided fine needle aspiration for resectable pancreatic body and tail cancer

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a first-line procedure for definitive tissue diagnosis of pancreatic cancer because of its high accuracy and low complication rate. The overall sensitivity of EUS-FNA for the diagnosis of pancreatic cancer is approximately 90%; however, its diagnostic ability for small lesions (<10 mm) remains limited. Although EUS-FNA is a relatively safe procedure, with an overall morbidity of ≤2%, it should be noted that needle tract seeding (NTS) can occur after EUS-FNA, which may affect the patient prognosis negatively. In patients with resected pancreatic tumors, preoperative EUS-FNA is not associated with an increased risk of postoperative recurrence. However, NTS after EUS-FNA for resectable pancreatic body and tail cancer has been highlighted recently, particularly by Japanese endoscopists. Thus, the use of preoperative EUS-FNA for the diagnosis of resectable pancreatic body and tail cancer has become a clinical dilemma that challenges gastroenterologists and must be carefully considered on a case-by-case basis by weighing the benefits and risks. This review summarizes the pros and cons of performing EUS-FNA in patients with resectable pancreatic body and tail cancer and provides valuable insight for gastroenterologists treating pancreatic cancer.

Adverse events of endoscopic ultrasound-guided fine-needle aspiration for histologic diagnosis in Japanese tertiary centers: Multicenter retrospective study

BACKGROUND AND AIMS

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is used for the histopathological diagnosis of any type of gastrointestinal disease. Few adverse events are experienced with this procedure; however, the actual rate of adverse events remains unclear. This study aimed to clarify the current status of cases that experienced adverse events related to the EUS-FNA procedure used for histopathologic diagnoses.

METHODS

A retrospective analysis of cases with EUS-FNA-related adverse events in Japanese tertiary centers was conducted by assessing the following clinical data: basic case information, FNA technique, type of procedural adverse events, and prognosis.

RESULTS

Of the 13,566 EUS-FNA cases overall, the total number of cases in which adverse events related to EUS-FNA occurred was 234. The incidence of EUS-FNA-related adverse events was ~1.7%. Bleeding and pancreatitis cases accounted for ~49.1% and 26.5% of all adverse events, respectively. Bleeding was the most common adverse event with only seven cases requiring blood transfusion. In cases with neuroendocrine tumors, pancreatitis was the most frequent adverse event. Needle tract seeding because of EUS-FNA was observed during the follow-up period in only ~0.1% of cases with pancreatic cancer. There was no mortality because of adverse events caused by EUS-FNA.

CONCLUSIONS

This study revealed that the adverse events-related EUS-FNA for histopathologic diagnoses were not severe conditions, and had low incidence.

Management Algorithms for Pancreatic Cystic Neoplasms: The Surgeon's Perspective

CONTEXT.—

The detection of pancreatic cystic neoplasms (PCNs) has increased owing to the advancement and widespread use of imaging modalities, resulting in differences between past and current management methods for PCNs, including intraductal papillary mucinous neoplasms (IPMNs). Therefore, clinicians should accurately diagnose and determine appropriate treatment strategies. However, previously published treatment guidelines for IPMNs present different indications for treatment.

OBJECTIVE.—

To review the current status of PCNs, including epidemiologic change, malignancy risk, and factors for treatment, and to provide the optimal management algorithms for PCNs, including IPMNs, from the clinician's point of view.

DATA SOURCES.—

Literature review of published studies and the authors' own work.

CONCLUSIONS.—

The treatment of PCNs relies on the type of cyst that is present or suspected. Serous cystic neoplasms are usually benign, and observation is sufficient. However, surgical treatment is required for mucinous cystic neoplasms, and malignancy risk differs according to lesion size. Solid pseudopapillary neoplasms also require surgery. The detection of small IPMNs has been increasing, and most branch duct-type IPMNs are dormant. However, cysts 3 cm or larger or growing branch duct-type IPMNs must be carefully monitored because of the increasing risk of malignancy. Therefore, surveillance strategies should be different according to the size of the lesions. A tailored approach is needed for selecting surgery or surveillance, considering the malignancy potential of the lesion and patient-associated factors such as operative risks and life expectancy. Nomograms are valuable tools for selecting treatment methods as a customized approach for IPMNs.

Peritoneal dissemination of pancreatic cancer caused by endoscopic ultrasound-guided fine needle aspiration: A case report and literature review

BACKGROUND

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a biopsy technique widely used to diagnose pancreatic tumors because of its high sensitivity and specificity. Although needle-tract seeding caused by EUS-FNA has been recently reported, dissemination of pancreatic cancer cells is generally considered to be a rare complication that does not affect patient prognosis. However, the frequency of dissemination and needle-tract seeding appears to have been underestimated. We present a case of peritoneal dissemination of pancreatic cancer due to preoperative EUS-FNA.

CASE SUMMARY

An 81-year-old man was referred to the Department of Surgery of our hospital in Japan owing to the detection of a pancreatic mass on computed tomography during medical screening. Trans-gastric EUS-FNA revealed that the mass was an adenocarcinoma; hence laparoscopic distal pancreatectomy with lympha-denectomy was performed. No intraoperative peritoneal dissemination and liver metastasis were visually detected, and pelvic lavage cytology was negative for carcinoma cells. The postoperative surgical specimen was negative for carcinoma cells at the dissected margin and the cut end margin; however, pathological findings revealed adenocarcinoma cells on the peritoneal surface proximal to the needle puncture site, and the cells were suspected to be disseminated via EUS- FNA. Hence, the patient received adjuvant therapy with S-1 (tegafur, gimeracil, and oteracil potassium); however, computed tomography performed 5 mo after surgery revealed liver metastasis and cancerous peritonitis. The patient received palliative therapy and died 8 mo after the operation.

CONCLUSION

The indications of EUS-FNA should be carefully considered to avoid iatrogenic dissemination, especially for cancers in the pancreatic body or tail.

Complications of Endoscopic Ultrasound-Guided Fine Needle Aspiration: A Narrative Review

Considerable progress has been made recently in the use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to diagnose intra-luminal gastrointestinal lesions and extra-luminal lesions near the gastrointestinal tract. Numerous reports have indicated that EUS-FNA has high diagnostic performance and safety, which has led to the routine use of EUS-FNA and an increasing number of cases. Thus, while EUS-FNA has a low rate of complications, endoscopists may encounter these complications as the number of cases increases. Infrequent reports have also described life-threatening complications. Therefore, endoscopists should possess a comprehensive understanding of the complications of EUS-FNA, which include hemorrhage, perforation, infection, and acute pancreatitis, as well as their management. This review examines the available evidence regarding the complications associated with EUS-FNA, and the findings will be useful for ensuring that endoscopists perform EUS-FNA safely and appropriately.

Overlooked risk for needle tract seeding following endoscopic ultrasound-guided minimally invasive tissue acquisition

Endoscopic ultrasound-guided minimally invasive tissue acquisition can be performed by two approaches as follows: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). These have been evolved into leading approaches and widely used for the histological diagnosis of tumors in the gastrointestinal tract and adjacent organs. However, the role of EUS-FNA and EUS-FNB in disease diagnosis and evaluation remains controversial. Although the incidence of surgery-associated complications remains low, the consequences of needle tract seeding can be serious or even life-threatening. Recently, increasing case reports of needle tract seeding are emerging, especially caused by EUS-FNA. This complication needs serious consideration. In the present work, we integrated these case reports and the related literature, and summarized the relevant cases and technical characteristics of needle tract seeding caused by EUS-FNA and EUS-FNB. Collectively, our findings provided valuable insights into the prevention and reduction of such serious complication.

Case Report of Isolated Gastric Metastasis of Pancreatic Cancer From a Diagnostic Biopsy: Management of a Rare Oncologic Entity

Pancreatic ductal adenocarcinoma behaves aggressively, with surgically resectable disease having the best chance of long-term survival. Recurrence after surgery and adjuvant therapy is commonly due to distant metastatic disease and is typically managed with systemic therapies, not surgery. We present a rare case of an isolated gastric metastasis due to endoscopic ultrasound-guided with fine-needle aspiration (EUS-FNA) needle tract seeding that was managed surgically. Treatment was informed by input from a mutlidisciplinary team of medical, surgical, and radiation oncologists, radiologists, and pathologists. Rising carbohydrate antigen (CA)19-9 levels suggested disease recurrence, but the tumor's unusual location and slow growth made diagnosing the cause difficult, resulting in the late identification of the tumor. Palliative resection was performed, rending the patient with no evidence of disease followed by normalized CA19-9 levels. This case highlights the importance of multidisciplinary decision-making in detecting and treating the uncommon but significant tumor seeding with EUS-FNA biopsies in pancreatic ductal adenocarcinoma.

Needle tract seeding and abscess associated with pancreatic fistula after endoscopic ultrasound-guided fine-needle aspiration

We present the first report of needle tract seeding with simultaneous abscess associated with pancreatic fistula occurring after endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for pancreatic ductal adenocarcinoma (PDA). A 72-year-old woman complained of fever 18 days after EUS-FNA for PDA of the pancreatic tail with a retention cyst. An abscess associated with pancreatic fistula containing necrotic debris formed in the EUS-FNA needle tract was successfully treated with endoscopic drainage and antibiotics. Distal pancreatectomy with partial gastrectomy was performed after neoadjuvant chemotherapy. Complete resection was achieved but peritoneal lavage cytology was positive for cancer. Pathology of the resected specimen revealed cancer cells invading the gastric submucosa at the EUS-FNA puncture site from the serosal side. The lining of the retention cyst was free of cancer cells. Liver metastases and peritoneal carcinomatosis were seen 3 months after surgery. While needle tract seeding has recently received attention as a complication of EUS-FNA, endoscopists should also be alerted to the possibility of abscess associated with pancreatic fistula after EUS-FNA for PDA.

Endoscopic Ultrasound-Guided Fine-Needle Aspiration Microhistology in Asymptomatic and Symptomatic Pancreatic Cystic Lesions

OBJECTIVE

This study aimed to analyze the usefulness of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) microhistology to detect malignancy in pancreatic cystic lesions (PCLs).

METHODS

Patients with PCLs were identified and submitted to EUS-FNA from January 2010 to January 2017. The percentage of samples suitable for diagnostic classification by microhistology and the positive and negative likelihood ratios to detect malignancy in asymptomatic (APC) and symptomatic (SPC) PCLs were determined.

RESULTS

Endoscopic ultrasound-guided fine-needle aspiration was performed in 510 patients. The resulting material was processed by microhistology and useful for diagnosis in 432 (84.2%). Clinical characteristics of APC (341) and SPC (169) revealed that APC patients were younger (P = 0.004) and had smaller PCLs (23 vs 35 mm; P < 0.001). In APC, we found more preneoplastic (38.7% vs 30.2%; P = 0.0016) and a lower number of malignant PCLs (8.2% vs 24.3%; P < 0.001). In APC and SPC, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of microhistology to detect malignancy were 71.4%, 99.7%, 95.2%, 97.5%, and 97.4% (k = 0.80) and 58.5%, 96.9%, 85.7%, 87.9%, and 87.6%, respectively.

CONCLUSIONS

Endoscopic ultrasound-guided fine-needle aspiration was technically feasible. Microhistology was especially useful to detect neoplastic or malignant PCLs in APC patients.

Seeding of a Tumor in the Gastric Wall after Endoscopic Ultrasound-guided Fine-needle Aspiration of Solid Pseudopapillary Neoplasm of the Pancreas

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is widely used as a first-line procedure for the definitive diagnosis of pancreatic solid tumor. Adverse events associated with the EUS-FNA procedure include acute pancreatitis, bleeding, infection, and duodenal perforation. Rarely, pancreatic tumors disseminate in the peritoneal cavity or seed in the gastric wall via the biopsy needle tract after EUS-FNA. Such seeding has been noted primarily in cases of adenocarcinomas and has not been associated with solid pseudopapillary neoplasm (SPN), a rare and potentially malignant tumor of the pancreas. This is the first report of a case of tumor seeding in the gastric wall after EUS-FNA of pancreatic SPN.

Needle tract seeding recurrence of pancreatic cancer in the gastric wall with paragastric lymph node metastasis after endoscopic ultrasound-guided fine needle aspiration followed by pancreatectomy: a case report and literature review

Background

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has high accuracy and a low complication rate; therefore, it has been widely used as a useful tool for diagnosis of and to determine treatment strategies for pancreatic tumors. Recently, reports of the recurrence of needle tract seeding after EUS-FNA are emerging.

Case presentation

An 83-year-old woman was referred to our hospital to undergo further examination of her pancreatic tumor. Multidetector computed tomography (MDCT) revealed a 25-mm-diameter mass in the pancreatic body. She underwent EUS-FNA (transgastric, 22-G needle, 2 passes) and was subsequently diagnosed with adenocarcinoma. Distal pancreatosplenectomy followed by adjuvant chemotherapy with S-1 for 6 months was performed. The level of carbohydrate antigen 19–9 gradually increased 22 months after surgery, and MDCT, which was performed 3 months later, revealed a 23-mm low-density mass in the stomach and paragastric lymph node swelling. Gastroendoscopy revealed a submucosal tumor, and endoscopic ultrasound revealed a hypoechoic mass in the submucosa of the gastric wall. Partial gastrectomy with lymph node resection was performed. The pathological findings showed adenocarcinoma extending from the subserosa to the submucosa and lymph node metastasis, consistent with a tumor recurrence from the resected pancreatic tumor. She received adjuvant chemotherapy with S-1; recurrence was not observed for 5 months, at the time of this writing.

Conclusion

It is important to pay careful attention to the development of needle tract seeding in patients with pancreatic cancer diagnosed by EUS-FNA. This is the first case of needle tract seeding with lymph node metastasis, highlighting the need for caution and providing novel insight in the postoperative follow-up of patients with pancreatic body/tail cancer.

Endoscopic ultrasonography for the evaluation of pancreatic cystic neoplasms

Endoscopic ultrasonography (EUS) is a modality with high spatial resolution that enables comprehensive observation of the entire pancreas and plays an important role in the diagnosis of pancreatic lesions. Recent advances in diagnostic imaging methods such as ultrasound, computed tomography, and magnetic resonance imaging have increased the incidental detection of pancreatic cystic lesions (PCLs). EUS has been recognized as an essential diagnostic method for the detection and evaluation of PCLs. EUS has two important roles: as a detailed (high-resolution) imaging diagnostic method and as an approach for collecting cyst fluid content by EUS-guided fine needle aspiration for pathological diagnosis or biomarker evaluation. Furthermore, in recent years, the usefulness of contrast-enhanced EUS for the differential diagnosis of PCLs or evaluation of grade of malignancy, and a novel imaging technique called needle-based confocal laser endomicroscopy to observe intraductal structures through a needle, has been reported. An understanding of the morphological characteristics of PCLs depicted by ultrasound imaging and of the benefits and limitations of EUS diagnosis in daily practice is needed.

Needle tract seeding following endoscopic ultrasound-guided fine-needle aspiration for pancreatic cancer: a report of two cases

Background

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a useful tool in pancreatic cancer diagnosis. However, the procedure itself may cause peritoneal dissemination and needle tract seeding at the puncture site. We herein report two cases of gastric wall metastasis due to needle tract seeding after EUS-FNA.

Case presentation

Case 1: A 68-year-old woman was admitted to our hospital for persistent cough. Computed tomography (CT) scan revealed inflammatory changes in the left lung field, and incidentally, a 15-mm hypovascular mass was detected in the pancreatic body. She underwent EUS-FNA and was diagnosed as pancreatic adenocarcinoma. She underwent distal pancreatectomy with splenectomy; however, a small hard mass was observed in the posterior gastric wall during surgery. We performed partial gastrectomy, and the resected specimen was diagnosed as a needle tract seeding following EUS-FNA. She then underwent adjuvant chemotherapy with TS-1, but the pancreatic cancer showed recurrence 6 months after surgery. She died due to peritoneal dissemination 18 months after surgery.

Case 2: A 70-year-old man was incidentally detected with a pancreatic body mass on a CT scan as part of his follow-up for recurrence of basal cell carcinoma. He underwent EUS-FNA and was diagnosed as pancreatic adenocarcinoma. He had nodules in both lungs, and it was difficult to differentiate them from lung metastasis of pancreatic cancer. Therefore, he underwent neoadjuvant chemoradiotherapy, and thereafter, the lung nodules showed no changes; hence, he underwent distal pancreatectomy with splenectomy. During surgery, we observed a hard mass in the posterior gastric wall. We performed partial gastrectomy, and the resected specimen was diagnosed as needle tract seeding due to EUS-FNA. He underwent chemotherapy with TS-1, and he is still alive 18 months after surgery at the time of writing.

Conclusion

For resectable pancreatic body or tail tumors, EUS-FNA should be carefully performed to prevent needle tract seeding and intraoperative as well as postoperative assessment for gastric wall metastasis is mandatory.

The safety and benefit of pancreatic juice cytology under ERCP in IPMN patients

BACKGROUND

International consensus guidelines 2012 for intraductal papillary mucinous neoplasia (IPMN), defined two characteristics: high-risk stigmata (HRS) and worrisome features (WF). Patients with WF require detailed examination including cytology. However, routine endoscopic retrograde cholangiopancreatography (ERCP) for cytology is not recommended in the guidelines due to risk of post-ERCP pancreatitis (PEP). Our aim was to clarify what types of IPMN were susceptible for PEP and gain benefit of ERCP.

PATIENTS/METHODS

We examined 138 consecutive IPMN patients who underwent ERCP in our hospital, retrospectively. Patients were classified into HRS, WF and the others (N) based on imaging findings before ERCP. We assessed pancreatic juice cytology, PEP frequency and rate of malignant IPMN at 12 months after ERCP.

RESULTS

The rates of cytological malignancy were 0% (N), 4.8% (WF) and 19.5% (HRS). The PEP frequency was 14.5%, and these risk factors were branch duct (BD)-IPMN, body/tail cysts and brush cytology by multivariate logistic analysis. The rates of malignant IPMN were 0% (N), 16.4% (WF) and 48.8% (HRS). Furthermore, we examined patients with WF in detail. The PEP frequency/rate of malignancy were 3.6%/23.1% in patients with main pancreatic duct (MPD) dilatation (5-9 mm), and the sensitivity of cytology was 33.3%. On the other hand, the PEP frequency/rate of malignancy were 17.2%/0% in patients with BD-IPMN fulfilling only cyst size over 30 mm.

CONCLUSIONS

Routine ERCP for IPMN, especially for BD-IPMN, is not recommended. ERCP may be beneficial for WF patients with MPD dilatation based on a balance between PEP risk and presence of malignancy.