Predictive factors for extraction of common bile duct stones during endoscopic retrograde cholangiopancreatography in Billroth II anatomy patients

BACKGROUND

Endoscopic retrograde cholangiopancreatography (ERCP) for extraction of common bile duct (CBD) stones in Billroth II anatomy patients is still a technical challenge and factors affecting stone extraction have not yet been clarified. This study aimed to analyze our experience and evaluate potential factors affecting CBD stone extraction.

METHODS

A retrospective analysis of CBD stones patients with a history of Billroth II gastrectomy, who underwent therapeutic ERCP for stone extraction at our center from August 1999 to December 2017, was conducted. The outcomes of ERCP and potential factors affecting stone extraction were examined.

RESULTS

A total of 227 patients were enrolled, and 176 patients (77.5%) achieved technical success. The success rate of duodenal ampullary access and selective biliary cannulation was 84.1% (191/227) and 92.1% (176/191), respectively. The mean CBD diameter was 15 mm (range 6-35 mm), and the largest stone size was 13 mm (range 4-36 mm). CBD stones were ultimately removed in 137 patients (77.8%), and 105 patients (59.7%) for the first session. Mechanical lithotripsy was used in 17 patients (9.7%). The overall ERCP-related complication rate was 6.3% (11/176), including bleeding in 3 patients (1.7%) and mild pancreatitis in 6 patients (3.4%). The multivariate analysis indicated that CBD stone number ≥ 2 (OR 2.171; 95% CI 1.095-4.306; p = 0.027), and the largest CBD stone size ≥ 12 mm (OR 3.646; 95% CI 1.833-7.251; p < 0.001) were patient-related risk factors for failed stone removal; while the use of endoscopic papillary (large) balloon dilation (EPBD/EPLBD) (OR 0.291; 95% CI 0.147-0.576; p < 0.001) was a procedure-related protective factor for successful stone extraction.

CONCLUSIONS

ERCP is safe and effective for extraction of CBD stones in Billroth II anatomy patients. The number and the largest size of CBD stones, and the use of EPBD/EPLBD are predictive factors for CBD stone extraction.

A prospective comparison of conventional cytology and digital image analysis for the identification of pancreatic malignancy in patients undergoing EUS-FNA

BACKGROUND AND OBJECTIVES

Digital image analysis (DIA) has been reported to be a sensitive method to detect pancreatic neoplasms by assessing nuclear DNA content. The aim of the current study was to evaluate the diagnostic performance of DIA for pancreatic malignancy relative to conventional cytology (CC) in patients undergoing EUS-FNA.

PATIENTS AND METHODS

One hundred and forty-two patients with suspected pancreatic malignancy were enrolled prospectively in this study. FNA sample from each patient was evenly divided and assessed by CC and DIA. Findings from histopathology of FNA specimens and a minimum 12-month follow-up were used as the standard.

RESULTS

Total 102 out of 142 patients were determined as pancreatic cancer (PC) in this study. The overall sensitivity, specificity, and accuracy of CC were 75%, 85%, and 78%, whereas the sensitivity, specificity, and accuracy of DIA were 84%, 80%, and 83%, respectively. A combination of CC and DIA (CC/DIA) showed greater sensitivity than CC alone (92% vs. 75%, P < 0.01), but the specificity was reduced from 85% to 70% (P = 0.03).

CONCLUSIONS

In this study, we demonstrated that DIA provided comparable diagnostic performance to CC in detecting PC. This objective diagnostic method, DIA, emerged as an important supplementary tool to endoscopic biopsy and cytology for diagnosing patients undergoing EUS-FNA with suspected pancreatic malignancy.

Defining the endoscopic ultrasound features of chronic pancreatitis in Asians: a multicenter validation study

BACKGROUND

Although endoscopic ultrasound (EUS) features and criteria have been described in chronic pancreatitis, challenges remain with interoperator variability and ease of adoption. The aim of this study was to define and validate the EUS features of chronic pancreatitis in a multicenter prospective study in Asia.

METHOD

The study was divided into two parts: the first part was conducted to derive the EUS features of chronic pancreatitis with adequate interoperator agreement; the second was to prospectively evaluate these features in a multicenter cross-sectional study and determine the optimal combination of features for the diagnosis of chronic pancreatitis. Prospectively enrolled cases had standard internationally validated radiologic or histologic features of chronic pancreatitis, and controls were patients without chronic pancreatitis who underwent EUS examination.

RESULTS

The top six EUS features that had good interobserver agreement (mean kappa 0.73, range 0.60 - 0.90) were selected to be further evaluated in part II of the study. These included: hyperechoic foci with shadowing, lobularity with honeycombing, cysts, dilated main pancreatic duct, dilated side branches, and calculi in the main pancreatic duct. A total of 284 subjects (132 cases, 152 controls) were enrolled from 12 centers in Asia. All six features had high accuracy ranging from 63.3 % to 89.1 %. Two or more of these six EUS features accurately defined chronic pancreatitis (sensitivity 94.7 %, specificity 98.0 %), with an area under the receiver operating curve of 0.986.

CONCLUSION

This multicenter Asian study characterized and defined the EUS features of chronic pancreatitis. This provides a useful tool in clinical practice and further research in pancreatic cancer surveillance.

22-Gauge biopsy needles have a better histological diagnostic yield in the discrimination of specific pancreatic solid neoplasms

BACKGROUND

To overcome the limitations of using cytological specimen alone for the diagnosis of challenging pancreatic lesions, biopsy needles have been developed to procure histological specimens during EUS, especially for the discrimination of several specific pancreatic tumors requiring adequate histological samples. The aim of this study was to compare the diagnostic yield of EUS-guided 22-gauge (G) fine needle aspiration (FNA) needles and 22G fine needle biopsy (FNB) needles for sampling pancreatic masses.

METHODS

We conducted a retrospective study of all EUS-guided sampling performed between November 2012 and April 2016. 422 cases sampled with a 22G FNA needle (N = 254) or a 22G FNB needle (N = 168) were recruited for this study. The specimen quality analyses, technical characteristics, accuracy, sensitivity, specificity, positive predictive values (PPVs), and negative predictive values (NPVs) for the pancreatic masses were reviewed and compared.

RESULTS

There was no significant difference in the procurement of adequate histological specimens (75.0% vs. 79.5%; p = .277) or the presence of diagnostic histological specimens (71.3% vs. 77.4%; p = .155) between FNA and FNB groups, respectively. There were also no significant differences in the accuracy, sensitivity, specificity, PPVs, or NPVs of the cytological, histological, and overall analyses for FNA and FNB groups in the diagnosis of pancreatic malignancy. However, 22G biopsy needles demonstrated a better histological diagnostic yield in the discrimination of pancreatic adenocarcinoma and non-adenocarcinoma pancreatic neoplasms than 22G FNA needles (69.8% vs. 57.9%, p = .033).

CONCLUSIONS

22G FNB needle demonstrated a better histological diagnostic yield in the differentiation between pancreatic adenocarcinoma and non-adenocarcinoma pancreatic neoplasms.

Antitumor Activity of Intratumoral Ethanol Injection in an Orthotopic Pancreatic Cancer Cell Mouse Xenograft Model

PURPOSE

Pancreatic cancer is a lethal disease and usually is diagnosed at advanced stages of disease. This study assessed the effects of intratumoral ethanol injection using an endoscopic ultrasound (EUS) probe on the control of pancreatic cancer in a mouse orthotopic xenograft model.

MATERIALS AND METHODS

The subcutaneous and orthotopic human pancreatic cancer cell mouse xenograft models were established. Different concentrations of ethanol (0-95%) were injected into subcutaneous xenograft tumors. In the orthotopic tumor model, ethanol was injected into the tumor lesions under the guidance of a high-frequency EUS probe. Tumor volume, relative tumor volume (RTV), and histopathology were evaluated. The serum amylase level was analyzed at baseline and 24 h after treatment in the orthotopic tumor model.

RESULTS

Injection of 40-95% ethanol induced tumor necrosis in the subcutaneous tumor model, while there was no statistical difference between the RTVs of the two groups (P = 0.81). In the orthotopic tumor model, the RTV of the 80% ethanol treatment group was less than that of the saline injection group (P < 0.01); and histologically, there was a large area of necrosis observed in the 80% ethanol group. The serum amylase level was slightly elevated at 24 h after injection and returned to the baseline level at 7 days.

CONCLUSION

Injection of 80% ethanol into xenograft tumor lesions of orthotopic pancreatic cancer resulted in tumor necrosis, and the procedure was safe and effective. Future studies will further confirm its antitumor activity as well as assess its safety and feasibility.

Diagnostic efficacy of three suction techniques for endoscopic ultrasound-guided fine-needle biopsy of solid pancreatic lesions: protocol for a multicenter randomized cross-over clinical trial

BACKGROUND

How suction technique affects endoscopic ultrasound-guided tissue acquisition (EUS-TA) remains unclear. A standardized protocol is currently lacking, with most previous studies being restricted to EUS-guided fine-needle aspiration (EUS-FNA). The research related to EUS-guided fine-needle biopsy (EUS-FNB) is sparse.

AIMS

The aim of this study is to evaluate the diagnostic efficacy, cellularity, tissue acquisition, blood contamination and adverse event rate of three common suction techniques (standard suction, slow-pull, and wet suction) used for EUS-FNB of solid pancreatic masses.

METHODS

This is a multicenter single-blind randomized cross-over superiority trial. A total of 300 patients with suspected pancreatic malignancy will be enrolled from digestive endoscopic centers at five large tertiary hospitals in China. All three suction techniques will be performed on each patient using a 25G ProCore needle, with the sequence of suction techniques determined by randomization. Cytological and histological specimens obtained with each of the three techniques will be assessed independently. Outcomes among the three suction techniques will be compared.

DISCUSSION

To the best of our knowledge, this is the largest multicenter randomized cross-over trial designed to determine the optimal suction technique for the diagnosis of solid pancreatic masses. This study may contribute to standardizing the suction technique for EUS-FNB.

Validation of a novel swine model for training in EUS-FNA (with videos)

BACKGROUND AND OBJECTIVES

EUS-FNA is applied widely in clinical practice, but there remains a lack of authentic training models. The present study aimed to develop a novel swine training model and to perform a preliminary assessment of its feasibility and efficacy.

MATERIALS AND METHODS

To create an internal lesion-like target, empty shells of iodine-125 seeds were implanted into the caudate lobe of the liver in Bama minipigs. A training program involving 10 trainees was subsequently carried out, in which a total of 60 needlings were performed, composed of 6 for each trainee obtained during two training steps. Comparisons of procedure-related variables were conducted between the two. Trainees completed a questionnaire to assess their basic endoscopic experiences and reasonability of the model.

RESULTS

A target region of 2.0 cm × 2.0 cm in diameter was successfully established on the caudate lobe in all implanted pigs. In the training program, the average procedure time decreased from the first to the second step and the average time for the total 30 needlings' obtainment was significantly shorter for the second training step (23.8 ± 4.5 min vs. 40.9 ± 9.0 min, P < 0.001). For the second step, there was also a significant improvement in total success rate (86.7% vs. 56.7%, P = 0.020) and accuracy rate (76.7% vs. 43.3%, P = 0.017). All trainees scored the effectiveness of the model highly and all reported improved confidence after the training.

CONCLUSION

This novel swine training model could authentically mimic clinical EUS-FNA, providing an effective in vivo practice tool for novices before clinical practice.

Optimal sampling technique for EUS-guided fine-needle biopsy of solid pancreatic lesions using a 25-gauge ProCore needle: A multicenter randomized crossover superiority study

BACKGROUND AND OBJECTIVES

It remains unclear whether the use of the stylet slow-pull (SP) and wet suction (WS) can improve the yield of endoscopic ultrasound-guided fine-needle biopsy compared to standard suction (SS). The aim of this study was to compare the diagnostic efficacy of the three sampling techniques when using 25G ProCore needles for solid pancreatic lesions.

MATERIALS AND METHODS

This multicenter single-blind randomized crossover superiority trial enrolled patients with solid pancreatic lesions (n = 300) from four digestive endoscopic centers in China. All three sampling techniques were performed on each patient using a 25G ProCore needle in a randomized sequence. The diagnostic efficacy, the specimen yield, and quality of each technique, the overall technical success rate and diagnostic yield of the 25G ProCore needle, and rate of adverse events were evaluated.

RESULTS

A total of 291 patients were analyzed. No significant difference was found in diagnostic efficiency among the three techniques (sensitivity, 82.14% vs. 75.00% vs. 77.86, P = 0.1186; accuracy, 82.82% vs. 75.95% vs. 78.69%, P = 0.1212). The SP had an inferior tissue integrity compared to the SS and WS techniques (71.82% vs. 62.55% vs. 69.76%, P = 0.0096). There was no significant difference in the degree of blood contamination among the three groups (P = 0.2079). After three passes, the overall sensitivity was 93.93%, and the accuracy was 94.16%.

CONCLUSIONS

SS and WS techniques are better choices than SP technique for 25G ProCore needle, for they could provide higher specimen adequacy without increasing the amount of blood contamination. The 25G ProCore needle can provide a satisfactory diagnostic yield for solid pancreatic lesions.

Rectally administered indomethacin to prevent post-ESWL-pancreatitis (RIPEP): study protocol for a randomized controlled trial

BACKGROUND

Pancreatic extracorporeal shock wave lithotripsy (P-ESWL) is the first-line therapy for large pancreatic duct stones. Although it is a highly effective and safe procedure for the fragmentation of pancreatic stones, it is still not complication-free. Just like endoscopic retrograde cholangiopancreatography (ERCP), pancreatitis is the most common complication. To date, nonsteroidal anti-inflammatory drugs (NSAIDs) have proven to be the only effective prophylactic medication for post-ERCP pancreatitis and the European, American and Japanese Society for Gastrointestinal Endoscopy guidelines have recommended prophylactic rectally administered indomethacin for all patients undergoing ERCP. Given the little research about effective prevention for post P-ESWL pancreatitis, we aim to determine whether rectally administered indomethacin can reduce post-ESWL-pancreatitis.

METHODS/DESIGN

The RIPEP study is a prospective, randomized, double-blinded, placebo-controlled trial. One thousand three hundred and seventy patients with chronic pancreatitis and pancreatic stones (>5 mm in diameter) treated with P-ESWL at Changhai Hospital will be randomly allocated to rectally administered indomethacin or placebo therapy before the procedure. The primary endpoint is the incidence of post-ESWL pancreatitis. Secondary endpoints include the severity of pancreatitis, occurrence rate of asymptomatic hyperamylasemia and other complications.

DISCUSSION

The RIPEP trial is designed to show that rectally administered indomethacin reduces the development and severity of post-ESWL pancreatitis and benefits patients treated with P-ESWL.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02797067 . Registered on 17 November 2016.

Endosonographers performing on-site evaluation of solid pancreatic specimens for EUS-guided biopsy: A formal training method and learning curves

OBJECTIVES

This study aimed to examine the effects of a training program combining formal cytological curriculum and practical assessments on endosonographers and to determine how many operations were needed for training through learning curves.

METHODS

A formal cytological curriculum was implemented in November 2019 for four endosonographers. The competency of endosonographers before and after the curriculum was judged by quantitative scores. From December 2019 to October 2020, trainees independently examined the adequacy and atypia grade of pancreatic specimens acquired by EUS-guided-fine-needle biopsy based on specific atypical grading criteria. The accuracy of the adequacy and atypia assessment of each trainee was calculated, and learning curves were drawn to evaluate the improvement.

RESULTS

The median posttraining score improved by 87% from 49 to 91.5 out of 100. Ninety patients were enrolled in the practical assessments. The accuracy for specimen adequacy and atypia assessment of each trainee was 91.7%, 92.8%, 91.0%, and 89.3% and 80.0%, 82.1%, 81.0%, and 78.9%. The learning curves of each trainee showed a steady and significant improvement, and ninety cases were sufficient for satisfactory adequacy assessment.

CONCLUSIONS

Basic knowledge of on-site cytopathologic evaluation can be gained through standardized and systematic training. Practical assessments showed that, at the completion of ninety cases, trained endosonographers reached a satisfactory level of recognizing specimen adequacy, but continue practice was needed for atypia assessment.

Use of simulator for EUS training in the diagnosis of pancreatobiliary diseases

BACKGROUND AND OBJECTIVES

EUS has been widely used in the diagnosis of pancreatobiliary diseases. However, improvements in the conventional training pattern of EUS are needed urgently. In this study, we compared the results achieved after use of clinical practice training patterns combined with or without simulator training and evaluated the effectiveness of simulator use in EUS training.

SUBJECTS AND METHODS

The trainees were randomly divided into two groups: the experimental group was trained with both clinical practice and simulator training system and the control group was only trained through clinical practice. After 1 month of training, trainees of both groups were tested with an established technical evaluation procedure that aimed to assess trainees' ability to examine the normal anatomical structure. Then, trainees in the experimental group completed a questionnaire.

RESULTS

The mean test score of the experimental group (64.53 ± 4.91) was significantly greater than that of the control group (60.09 ± 5.49; P= 0.028). Moreover, the individual test score of trainees in the experimental group was positively correlated with the frequency of simulator use (P = 0.242).

CONCLUSION

Simulator training can promote trainees' ability to evaluate the normal anatomical structure, and thus, can improve the efficiency of the EUS training program.

Establishment and validation of a computer-assisted colonic polyp localization system based on deep learning

BACKGROUND

Artificial intelligence in colonoscopy is an emerging field, and its application may help colonoscopists improve inspection quality and reduce the rate of missed polyps and adenomas. Several deep learning-based computer-assisted detection (CADe) techniques were established from small single-center datasets, and unrepresentative learning materials might confine their application and generalization in wide practice. Although CADes have been reported to identify polyps in colonoscopic images and videos in real time, their diagnostic performance deserves to be further validated in clinical practice.

AIM

To train and test a CADe based on multicenter high-quality images of polyps and preliminarily validate it in clinical colonoscopies.

METHODS

With high-quality screening and labeling from 55 qualified colonoscopists, a dataset consisting of over 71000 images from 20 centers was used to train and test a deep learning-based CADe. In addition, the real-time diagnostic performance of CADe was tested frame by frame in 47 unaltered full-ranged videos that contained 86 histologically confirmed polyps. Finally, we conducted a self-controlled observational study to validate the diagnostic performance of CADe in real-world colonoscopy with the main outcome measure of polyps per colonoscopy in Changhai Hospital.

RESULTS

The CADe was able to identify polyps in the test dataset with 95.0% sensitivity and 99.1% specificity. For colonoscopy videos, all 86 polyps were detected with 92.2% sensitivity and 93.6% specificity in frame-by-frame analysis. In the prospective validation, the sensitivity of CAD in identifying polyps was 98.4% (185/188). Folds, reflections of light and fecal fluid were the main causes of false positives in both the test dataset and clinical colonoscopies. Colonoscopists can detect more polyps (0.90 vs 0.82, P < 0.001) and adenomas (0.32 vs 0.30, P = 0.045) with the aid of CADe, particularly polyps < 5 mm and flat polyps (0.65 vs 0.57, P < 0.001; 0.74 vs 0.67, P = 0.001, respectively). However, high efficacy is not realized in colonoscopies with inadequate bowel preparation and withdrawal time (P = 0.32; P = 0.16, respectively).

CONCLUSION

CADe is feasible in the clinical setting and might help endoscopists detect more polyps and adenomas, and further confirmation is warranted.

Endoscopic papillectomy of benign papillary tumors: A single-center experience

Endoscopic treatment of duodenal papillary tumors is well described. This study aims to provide new evidence for the treatment of benign papillary tumors through comparisons between endoscopic snare papillectomy (ESP) and endoscopic mucosal resection (EMR).Between May 2010 and December 2017, 72 patients were enrolled. Diagnosis and treatment procedures were ESP and EMR. Endoscopic follow-up evaluation was done periodically as a surveillance measurement for recurrence.Seventy-two patients with ampullary tumors were enrolled, of which 66 had adenomas including 9 high-grade intraepithelial neoplasias and 2 carcinomas in adenoma. Complete resections with tumor-free lateral and basal margins were achieved in all patients. Postoperative complications were bleeding (9.5% in EMR vs 10% in ESP) and pancreatitis (2.4% in EMR and 3.3% in ESP), with no occurrence of perforation, cholangitis or papillary stenosis. Adenoma recurrence was found in 7 patients (14.3% in EMR vs 3.3% in ESP) at 1 year.The ESP procedure is safe and effective for benign ampullary adenoma, high-grade intraepithelial neoplasias, and noninvasive cancer without intraductal tumor growth, which has a shorter procedural duration, as well as lower complication, recurrence rates and hospitalization costs.

High-Risk Characteristics Associated with Advanced Pancreatic Cystic Lesions: Results from a Retrospective Surgical Cohort

BACKGROUND AND AIM

The management of pancreatic cystic lesions (PCLs) remains controversial. We performed a retrospective study to determine characteristics associated with advanced PCLs (A-PCLs) and whether these characteristics vary in different pathological types of PCLs. The additional diagnostic value of endoscopic ultrasound (EUS) was also evaluated.

METHODS

Patients who underwent surgical resection for an identified PCLs by imaging modalities were included. A logistic regression model was developed to identify significant characteristics for A-PCLs. EUS data was assessed separately.

RESULTS

Three hundred and fifty-three patients were included, and 125 patients (35.4%) were A-PCLs. The presence of main pancreatic duct (MPD) diameter ≥ 10 mm (odds ratio [OR], 11.7; 95% confidence interval [CI], 1.53-89.2; P = 0.018), mural nodules ≥ 5 mm (OR, 11.67; 95% CI, 2.3-59.05; P = 0.003), solid components within cysts (OR, 30.87; 95% CI, 7.23-131.7; P < 0.0001) and high serum CA19-9 levels (OR, 1.006; 95% CI, 1.001-1.011; P = 0.02) were independently associated with the presence of A-PCLs. The presence of septa was independently associated with the presence of non-A-PCLs (OR, 0.147; 95% CI, 0.04-0.6; P = 0.008). Males who had a history of tobacco abuse (P < 0.0001) and had a greatly dilated MPD (P < 0.0001) were more common in advanced intraductal papillary mucinous neoplasms (IPMC) patients. Solid pseudopapillary neoplasm (SPT) often occurred in young women (P < 0.0001), mostly asymptomatically (P < 0.0001) and with lower serum CA19-9 levels (P < 0.0001). In the 124 patients who underwent EUS-guided fine-needle aspiration (EUS-FNA), five additional characteristics (4 mural nodules and 1 MPD involvement) were identified by EUS imaging and 17 patients were identified with abnormal cytological results (13 atypical cells and 4 suspicious for malignancy cells) by EUS-FNA.

CONCLUSION

On the basis of a retrospective study with large sample size, the presence of MPD ≥ 10 mm, mural nodules, solid components, and high serum CA19-9 levels were independently associated with the presence of A-PCLs. The high-risk characteristics may vary across different types of A-PCLs. EUS and EUS-FNA could provide additional diagnostic information for PCLs.

A retrospective multicenter study comparing bupivacaine and ropivacaine in endoscopic ultrasound guided celiac plexus neurolysis

BACKGROUND

Endoscopic ultrasound-guided celiac plexus neurolysis (EUS-CPN) is widely practiced to palliate cancer pain in patients with inoperable abdominal malignancy. During CPN, the dehydrated alcohol is injected to ablate neural tissue and local anesthetics is to minimize the discomfort from alcohol injection. This study aims to compare the efficacy and safety of bupivacaine and ropivacaine in EUS-CPN.

METHODS

We retrospectively pooled and analyzed two large EUS centers' 150 consecutive patients underwent EUS-CPN from January 2012 to March 2019. Patients were divided into 3 groups based on the selection of anesthetics: 0.5% ropivacaine (ROPI, n=23), 0.375% bupivacaine (0.375% BUPI, n=21), 0.75% bupivacaine (0.75% BUPI, n=106). Visual analogue scale (VAS) was used to measure pre/post-operative pain at 11 observation points. Additional data were collected from medical records.

RESULTS

The incidence of procedure-related pain within 12 hours after CPN was significantly different among the three groups, 10.38% in 0.75% BUPI [OR =0.26 (95% CI: 0.07-0.94); P=0.04], 26.09% in ROPI and 23.81% in 0.375% BUPI group, respectively. The risk of post-procedural arrhythmia was similar between the 0.375% and 0.75% BUPI groups (19.05% versus 18.87%), while relatively lower in ROPI group (13.04%). No patients in any group developed symptoms of CNS toxicity related to anesthetics.

CONCLUSIONS

Compared with 0.375% bupivacaine and 0.5% ropivacaine, 0.75% bupivacaine in CPN can reduce post-procedural pain. Ropivacaine shows a tendency of less arrhythmogenic effect in CPN.

Independent risk factors for true malignancy in atypical cytologic diagnostic category in EUS-FNA/FNB of the pancreas: A novel prediction model

BACKGROUND AND OBJECTS

An atypical cytologic diagnosis arises from inflammation or early neoplastic process. It is commonly found in EUS-guided fine-needle aspiration/biopsy (EUS-FNA/FNB) tissue sampling of pancreatic malignancies. The aims of this study were to evaluate the diagnostic performance of EUS-FNA/FNB in patients with cytologic diagnosis of atypical cells and to develop a prediction model for malignant tumors of the pancreas in the atypical cytologic diagnostic category.

METHODS

Two hundred and twenty-six patients in the atypical cytologic diagnostic category were analyzed. Multivariate logistic regression analyses were performed to determine predictive factors for pancreatic malignancies. The final diagnoses were confirmed by repeat biopsy; surgical pathology, or clinical follow-up for at least 6 months.

RESULTS

The atypical cytologic diagnosis using EUS-FNA/FNB was associated with an absolute risk of malignancy (82.3%). Multivariate logistic regression analyses revealed that older age, long axis of the mass, and increased carbohydrate antigen 19-9 (CA19-9) were independent risk factors for true malignant pancreatic tumors among patients in the atypical cytologic diagnostic category. The calibration curve had a slope of 0.96, and a regression coefficient (R2) of 0.91. The area under the receiver operating characteristic curve of the validation group was 0.803.

CONCLUSIONS

Atypical lesions of EUS-FNA/FNB have a higher risk of malignancy. Older age, the long axis of the mass, and elevated serum CA19-9 level were identified as independent risk factors for true malignant pancreatic tumors among patients in the atypical cytologic diagnostic category.