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

Endoscopic ultrasound‑guided fine‑needle aspiration for unresectable pancreatic metastasis of esophageal squamous cell carcinoma: A case report and literature review

Metastatic tumors to the pancreas are a rare subtype of pancreatic malignant tumor, particularly those that have spread from the esophagus. The diagnosis and treatment process can be complex when managing patients with tumors that have metastasized to the pancreas. Accurate differentiation between primary pancreatic and metastatic tumors is key in the use of precision therapy for these patients. The present study reports the case of a 53-year-old female patient that presented with symptoms of dysphagia and epigastric pain that had persisted for 3 months. Gastroscopy indicated the presence of a tumor in the lower esophagus, with pathology results demonstrating squamous cell carcinoma. Prior to radical esophageal cancer surgery, computed tomography (CT) scans demonstrated the presence of a tumor in the body of the pancreas. Due to the notable size of the tumor and potential involvement of the large abdominal vessels, esophageal surgery was postponed and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed to confirm the pathological diagnosis. EUS-FNA pathological diagnosis demonstrated that the pancreatic tumor was a result of esophageal tumor metastasis. The patient opted for radiotherapy and chemotherapy for both the esophageal and pancreatic tumors instead of undergoing surgery. The present study reports the clinical and pathological characteristics, and treatment strategies of rare metastatic tumors to the pancreas of esophageal origin.

A case of needle tract seeding of pancreatic adenosquamous carcinoma after a single endoscopic ultrasound-guided tissue acquisition

Needle tract seeding (NTS) is a rare complication of endoscopic ultrasound-guided tissue acquisition (EUS-TA). Herein, we report the case of an 83 year-old man who presented with a solid mass in the pancreatic tail, measuring 35 mm in diameter, with cystic degeneration. EUS-TA was performed using a 22-gauge biopsy needle, with a single puncture via the stomach; however, no definitive pathological diagnosis was achieved. Due to the strong suspicion of malignancy, surgery was performed at the patient's request, and the postoperative pathological diagnosis was pancreatic adenosquamous carcinoma. One year after surgery, computed tomography revealed a string of bead-like nodules within the gastric wall. Esophagogastroduodenoscopy revealed three submucosal, tumor-like raised lesions aligned in a row on the upper posterior wall of the gastric body. EUS detected a solid mass with cystic degeneration. Histological findings from EUS-TA specimens were consistent with those from the pancreatic resection specimen, leading to a diagnosis of NTS. Although reports of NTS have been increasing in recent years, cases of NTS occurring after only a single puncture remain extremely rare. This case clearly demonstrates that NTS can occur even after a single puncture, highlighting the importance of obtaining thorough informed consent regarding this risk prior to performing EUS-TA.

Targeting the CSF1/CSF1R signaling pathway: an innovative strategy for ultrasound combined with macrophage exhaustion in pancreatic cancer therapy

Pancreatic cancer (PC) is a highly aggressive and lethal malignancy characterized by a complex tumor microenvironment (TME) and immunosuppressive features that limit the efficacy of existing treatments. This paper reviews the potential of combining ultrasound with macrophage exhaustion in the treatment of pancreatic cancer. Macrophages, particularly tumor-associated macrophages (TAMs), are crucial in pancreatic cancer progression and immune escape. Prolonged exposure to the immunosuppressive TME leads to macrophage exhaustion, reducing their anti-tumor ability and instead promoting tumor growth. The CSF1/CSF1R signaling pathway is key in macrophage recruitment and functional regulation, making it an effective target for combating macrophage exhaustion. Ultrasound technology not only plays a significant role in diagnosis and staging but also enhances therapeutic efficacy by guiding radiofrequency ablation (RFA) and percutaneous alcohol injection (PEI) in combination with immunomodulators. Additionally, ultrasound imaging can monitor the number and functional status of TAMs in real-time, providing a basis for optimizing treatment strategies. Future studies should further investigate the combined use of ultrasound and immunomodulators to refine treatment regimens, address challenges such as individual variability and long-term effects, and offer new hope for pancreatic cancer patients.

Collection of serum albumin aggregate nanoparticles from human plasma by dielectrophoresis

Dielectrophoresis (DEP) is a fast and reliable nanoparticle recovery method that utilizes nonuniform electric fields to manipulate particles based on their material composition and size, enabling recovery of biologically-derived nanoparticles from plasma for diagnostic applications. When applying DEP to undiluted human plasma, collection of endogenous albumin proteins was observed at electric field gradients much lower than predicted by theory to collect molecular proteins. To understand this collection, nanoparticle tracking analysis of bovine serum albumin (BSA) dissolved in 0.5× phosphate-buffered saline was performed and showed that albumin spontaneously formed aggregate nanoparticles with a mean diameter of 237 nm. These aggregates experienced a dielectrophoretic force as a function of aggregate radius rather than the diameter of individual protein molecules which contributed to their collection. In high conductance buffer (6.8 mS/cm), DEP was able to move these aggregates into regions of high electric field gradient, and in lower conductance buffer (0.68 mS/cm), these aggregates could be moved into high or low gradient regions depending on the applied frequency. Disruption of BSA aggregates using a nonionic detergent significantly decreased the particle diameter, resulting in decreased dielectrophoretic collection of albumin which increased the collection consistency of particles of interest. These results provide techniques to manipulate albumin aggregates via DEP, which impacts collection of diagnostic biomarkers.

Pancreatic juice cytology for diagnosing invasive pancreatic carcinoma/high-grade pancreatic intraepithelial neoplasia without visible tumors on endoscopic ultrasound

OBJECTIVES

Pancreatic ductal adenocarcinoma (PDAC) with a diameter ≤10 mm and high-grade pancreatic intraepithelial neoplasia (HG-PanIN) require pre-operative diagnosis. Most cases present only indirect imaging findings without visible tumors on endoscopic ultrasound (EUS). Therefore, EUS-guided fine-needle aspiration/biopsy is not applicable. An alternative diagnostic method is pancreatic juice cytology (PJC) via endoscopic naso-pancreatic drainage (ENPD-PJC), which is not the standard practice. This study aimed to investigate ENPD-PJC for diagnosing suspected PDAC/HG-PanIN cases without visible tumors on EUS.

METHODS

Data of patients with suspected PDAC/HG-PanIN without visible tumors who underwent PJC were retrospectively evaluated. One PJC sample was collected during endoscopic retrograde pancreatography (ERP-PJC), and 12 samples were collected during ENPD-PJC, 3-hourly for cytological analysis. ERP-PJC, ERP/ENPD-PJC, and ENPD-PJC positivity indicated cytologically positive samples. Patients with positive/negative PJC with follow-up for <4-years were excluded as undiagnosed cases. A non-malignant diagnosis was based on histopathological absence/stable imaging findings for ≥4-years. The primary endpoint was to demonstrate that ERP/ENPD-PJC has a higher diagnostic ability than ERP-PJC.

RESULTS

Twenty-two patients with histopathologically diagnosed PDAC/HG-PanIN and 31 with a non-malignant diagnosis were enrolled. ERP-PJC, ERP/ENPD-PJC, and ENPD-PJC showed sensitivities of 36.4 %, 86.4 %, and 77.3 %, specificities of 93.5 %, 87.1 %, and 93.5 %, and accuracies of 69.8 %, 86.7 %, and 86.7 %, respectively. ERP/ENPD-PJC and ENPD-PJC demonstrated superior sensitivity and accuracy compared to ERP-PJC. A greater occurrence of positive outcomes markedly distinguished true positives from false positives.

CONCLUSIONS

ERP/ENPD-PJC and ENPD-PJC had higher diagnostic accuracies for PDAC/HG-PanIN without visible tumors on EUS. ENPD-PJC is recommended for the diagnosis of these lesions.

Applications of spatial transcriptomics and artificial intelligence to develop integrated management of pancreatic cancer

Cancer is a complex disease intrinsically associated with cellular processes and gene expression. With the development of techniques such as single-cell sequencing and sequential fluorescence in situ hybridization (seqFISH), it was possible to map the location of cells based on their gene expression with more precision. Moreover, in recent years, many tools have been developed to analyze these extensive datasets by integrating machine learning and artificial intelligence in a comprehensive manner. Since these tools analyze sequencing data, they offer the chance to analyze any tissue regardless of its origin. By applying this to cancer settings, spatial transcriptomic analysis based on artificial intelligence may help us understand cell-cell communications within the tumor microenvironment. Another advantage of this analysis is the identification of new biomarkers and therapeutic targets. The integration of such analysis with other omics data and with routine exams such as magnetic resonance imaging can help physicians with the earlier diagnosis of tumors as well as establish a more personalized treatment for pancreatic cancer patients. In this review, we give an overview description of pancreatic cancer, describe how spatial transcriptomics and artificial intelligence have been used to study pancreatic cancer and provide examples of how integrating these tools may help physicians manage pancreatic cancer in a more personalized approach.

Oil blotting paper for formalin fixation increases endoscopic ultrasound-guided tissue acquisition-collected sample volumes on glass slides

OBJECTIVES

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is used for pathological diagnosis and obtaining samples for molecular testing, facilitating the initiation of targeted therapies in patients with pancreatic cancer. However, samples obtained via EUS-TA are often insufficient, requiring more efforts to improve sampling adequacy for molecular testing. Therefore, this study investigated the use of oil blotting paper for formalin fixation of samples obtained via EUS-TA.

METHODS

This prospective study enrolled 42 patients who underwent EUS-TA for pancreatic cancer between September 2020 and February 2022 at the Osaka International Cancer Institute. After a portion of each sample obtained via EUS-TA was separated for routine histological evaluation, the residual samples were divided into filter paper and oil blotting paper groups for analysis. Accordingly, filter paper and oil blotting paper were used for the formalin fixation process. The total tissue, nuclear, and cytoplasm areas of each sample were quantitatively evaluated using virtual slides, and the specimen volume and histological diagnosis of each sample were evaluated by an expert pathologist.

RESULTS

All cases were cytologically diagnosed as adenocarcinoma. The area ratios of the total tissue, nuclear, and cytoplasmic portions were significantly larger in the oil blotting paper group than in the filter paper group. The frequency of cases with large amount of tumor cells was significantly higher in the oil blotting paper group (33.3%) than in the filter paper group (11.9%) (p = 0.035).

CONCLUSIONS

Oil blotting paper can increase the sample volume obtained via EUS-TA on glass slides and improve sampling adequacy for molecular testing.

Droplet digital polymerase chain reaction detection of KRAS mutations in pancreatic FNA samples: Technical and practical aspects for routine clinical implementation

BACKGROUND

Pancreatic adenocarcinoma (PDAC) is associated with a 5-year survival rate of less than 6%, and current treatments have limited efficacy. The diagnosis of PDAC is mainly based on a cytologic analysis of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) samples. However, the collected specimens may prove noncontributory in a significant number of cases, delaying patient management and treatment. The combination of EUS-FNA sample examination and KRAS mutation detection can improve the sensitivity for diagnosis. In this context, the material used for molecular analysis may condition performance.

METHODS

The authors prospectively compared the performance of cytologic analysis combined with a KRAS droplet digital polymerase chain reaction (ddPCR) assay for PDAC diagnosis using either conventional formalin-fixed, paraffin-embedded cytologic samples or needle-rinsing fluids.

RESULTS

Molecular testing of formalin-fixed, paraffin-embedded cytologic samples was easier to set up, but the authors observed that the treatment of preanalytic samples, in particular the fixation process, drastically reduced ddPCR sensitivity, increasing the risk of false-negative results. Conversely, the analysis of dedicated, fresh needle-rinsing fluid samples appeared to be ideal for ddPCR analysis; it had greater sensitivity and was easily to implement in clinical use. In particular, fluid collection by the endoscopist, transportation to the laboratory, and subsequent freezing did not affect DNA quantity or quality. Moreover, the addition of KRAS mutation detection to cytologic examination improved diagnosis performance, regardless of the source of the sample.

CONCLUSIONS

Considering all of these aspects, the authors propose the use of an integrated flowchart for the KRAS molecular testing of EUS-FNA samples in clinical routine.

Endoscopic ultrasound-guided fine-needle aspiration for pancreatic cystic lesions: a comprehensive review

Advancements in diagnostic radiology have amplified the incorporation of these techniques into routine clinical practice. Concurrently, the frequency of incidentally identifying pancreatic cystic lesions (PCLs) has surged. PCLs encompass diverse categories contingent upon their origin. Among them, branch duct-intraductal papillary mucinous neoplasms (BD-IPMN) and mucinous cystic neoplasms (MCN) are categorized as mucinous cystic lesions that have malignant potential. Even solid neoplasms occasionally show cystic degeneration. Therefore, precise differential PCL diagnosis is crucial to optimize clinical management strategies and detect malignant transformations. Endoscopic ultrasound (EUS) affords comprehensive visualization of the pancreas with high-resolution ultrasound, complemented by fine-needle aspiration (FNA) under real-time EUS guidance, which is a minimally invasive procedure for obtaining pathological samples. This synergy has established EUS and EUS-FNA as vital procedures in the management of PCLs, enabling differentiation of PCLs. Cyst fluid analysis has played a pivotal role in deciding the optimal management strategy. The efficacy of cytological analysis is limited by scant cytologic material. The "string sign" test evaluates fluid viscosity, and its simplicity warrants initial consideration. Amylase and tumor markers, such as CEA, have been studied, but they yield varied sensitivity and specificity. Glucose and genetic mutations (KRAS, GNAS) exhibit promise, while comprehensive genomic profiling underscores genetic insights. Through-the-needle biopsy and needle-based confocal laser endomicroscopy also show high diagnostic yield. EUS-FNA, however, entails risks like infection and needle tract seeding, emphasizing the need for proper utilization. Pancreatic cyst fluid analysis augments diagnostic accuracy and informs clinical decisions, making it a valuable adjunct to imaging.

A case of needle tract seeding with endoscopic findings of progression over time

An 83-year-old male underwent three transgastric punctures with endoscopic ultrasound-guided fine-needle aspiration for the examination of a pancreatic body tumor. After a diagnosis of resectable pancreatic cancer and undergoing distal pancreatectomy, the patient was administered postoperative adjuvant chemotherapy with oral S-1 for 6 months, and carcinoembryonic antigen and carbohydrate antigen 19-9 levels were bimonthly evaluated. Carbohydrate antigen 19-9 levels continually increased to 4638.1 U/mL at 45 months post-fine-needle aspiration. Endoscopic ultrasound-guided showed a 25 mm low-echoic, irregularly shaped, and heterogeneous tumor with clear margins protruding from the mucosa outside the gastric wall, and biopsy confirmed adenocarcinoma. Since the immunostaining findings of the specimen matched those of the previously resected specimen, needle tract seeding (NTS) due to puncture of the pancreatic cancer was identified as the cause. After a pylorus-preserving gastrectomy at 46 months post-fine-needle aspiration, postoperative chemotherapy initiation, comprising gemcitabine and nab-paclitaxel, was initiated; however, the patient died despite these interventions as he developed multiple peritoneal dissemination. Although rare, the incidence of NTS will increase in the future owing to the expected extended survival in post-pancreatic cancer resection cases. We suggest regular upper gastrointestinal endoscopy and endoscopic ultrasound-guided evaluations for patients who are at risk for NTS can facilitate early detection. Furthermore, it is extremely relevant to share experiences of encountered NTS cases in practice and extend knowledge of its varying endoscopic appearances.

The history of endoscopic ultrasound-guided fine-needle aspiration: development and progress

Endoscopic ultrasonography (EUS) is an important diagnostic technique to accurately diagnose diseases originating from organs near the gastrointestinal tract. EUS-guided fine-needle aspiration (FNA) has improved the histopathological diagnosis. EUS-FNA has been further developed over a long period of 40 years. The history of the development of endosonographic scopes, ultrasonographic observation systems, puncture needles, and puncture methods will provide a springboard for future development.

True diagnostic ability of EUS-guided fine-needle aspiration/biopsy sampling for small pancreatic lesions ≤10 mm and salvage diagnosis by pancreatic juice cytology: a multicenter study

BACKGROUND AND AIMS

The diagnostic performance of EUS-guided fine-needle aspiration/biopsy sampling (EUS-FNAB) for pancreatic ductal adenocarcinoma (PDAC) ≤10 mm in diameter is relatively low. Pancreatic juice cytology (PJC) has gained attention because of its high sensitivity for small PDACs. We aimed to clarify the diagnostic ability of EUS-FNAB and the salvage ability of PJC for PDAC ≤10 mm.

METHODS

Data obtained from attempted EUS-FNAB for patients with EUS-confirmed pancreatic tumors ≤10 mm (excluding pancreatic metastases/malignant lymphomas) were retrospectively analyzed. Patients who experienced technical failure or had a negative EUS-FNAB result and had a strong likelihood of PDAC based on imaging characteristics underwent PJC. PDAC was diagnosed using resected histologic specimens, EUS-FNAB-positive tumor growth on the imaging examination, or additional EUS-FNAB-positive results after increase in tumor size. The primary endpoint was the diagnostic ability of EUS-FNAB for PDAC ≤10 mm. The salvage ability of PJC was also assessed.

RESULTS

Overall, 86 of 271 patients with pancreatic tumors ≤10 mm who underwent attempted EUS-FNAB were diagnosed with PDAC. The technical success rate, sensitivity, specificity, and accuracy of EUS-FNAB for PDAC ≤10 mm were 80.8%, 82.3%, 94.9%, and 91.3%, respectively. Among the 35 PDAC patients who experienced technical failure or false-negative results of EUS-FNAB, 26 (74.3%) were correctly diagnosed using salvage PJC.

CONCLUSIONS

The true success rate and sensitivity of EUS-FNAB for PDAC ≤10 mm were relatively low. When EUS-FNAB for a pancreatic lesion ≤10 mm strongly suspected to be PDAC is unsuccessful or yields a negative result, PJC is recommended. (Clinical trial registration number: UMIN000049965.).

Efficacy of staging laparoscopy for resectable pancreatic cancer on imaging and the therapeutic effect of systemic chemotherapy for positive peritoneal cytology

BACKGROUND

The frequency and prognosis of positive peritoneal washing cytology (CY1) in resectable pancreatic ductal adenocarcinoma (R-PDAC) remains unclear. The objective of this study was to identify the clinical implications of CY1 in R-PDAC and staging laparoscopy (SL).

METHODS

We retrospectively analyzed 115 consecutive patients with R-PDAC who underwent SL between 2018 and 2022. Patients with negative cytology (CY0) received radical surgery after neoadjuvant chemotherapy, while CY1 patients received systemic chemotherapy and were continuously evaluated for cytology.

RESULTS

Of the 115 patients, 84 had no distant metastatic factors, 22 had only CY1, and nine had distant metastasis. Multivariate logistic regression revealed that larger tumor size was an independent predictor of the presence of any distant metastatic factor (OR: 6.30, p = .002). Patients with CY1 showed a significantly better prognosis than patients with distant metastasis (MST: 24.6 vs. 18.9 months, p = .040). A total of 11 CY1 patients were successfully converted to CY-negative, and seven underwent conversion surgery. There was no significant difference in overall survival between patients with CY0 and those converted to CY-negative.

CONCLUSION

SL is effective even for R-PDAC. The prognosis of CY1 patients converted to CY-negative is expected to be similar to that of CY0 patients.

Isolated pancreatic tuberculosis masquerading as malignancy in an immunocompetent host: a case report and review of the literature

A 41-year-old man was admitted to our department with a 7-day history of jaundice of the skin. He was misdiagnosed with carcinoma because imaging tests showed a space-occupying lesion in the pancreatic head, and laboratory examinations showed elevated liver enzymes, and elevated serum bilirubin, alpha-fetoprotein, carbohydrate antigen 19-9, and ferroprotein levels. However, there was slight calcification in the lesion and a subsequent T-Spot test result was positive. The patient then underwent endoscopic retrograde cholangiopancreatography for biopsy and bile drainage. Histologically, the pancreatic mass showed granulomatosis, and the pathologic diagnosis of the isolated pancreatic neoplasm was tuberculosis. The patient accordingly received anti-tuberculosis agents, resulting in a significant decrease in the size of the pancreatic mass. The patient recovered well. Pancreatic tuberculosis can masquerade as malignancy; however, careful attention to a differential diagnosis can prevent the need for laparotomy.

Pancreatic Juice Cytology Evaluations Using Synthetic Secretin and Serial Pancreatic Juice Aspiration Cytological Examination for the Diagnosis of Pancreatic Ductal Adenocarcinoma

Pathological examination by endoscopic ultrasound-fine needle aspiration is not possible in approximately 10% of pancreatic tumor cases. Pancreatic juice cytology (PJC) is considered an alternative diagnostic method. However, its diagnostic capability is insufficient, and PJC has been repeatedly redevised. Serial pancreatic juice aspiration cytological examination (SPACE) and secretin-loaded PJC (S-PJC) have been recently introduced as alternative diagnostic methods. This study aimed to determine the diagnostic capacity and safety of SPACE and S-PJC using a propensity score-matched analysis. The sensitivity, specificity, and accuracy were 75.0%, 100%, and 92.3% for S-PJC, respectively, and 71.4%, 100%, and 92.3% for SPACE, respectively, meaning that there was no significant difference between the groups. Four patients (15.4%) each in the S-PJC and SPACE groups experienced complications, including postendoscopic retrograde cholangiopancreatography, pancreatitis, and cholangitis. Overall, there was no difference in efficacy and safety between the SPACE and S-PJC groups.

Case of needle tract seeding during preoperative neoadjuvant chemotherapy for resectable pancreatic cancer

Reports of needle tract seeding (NTS) as a complication of endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) have been increasing. To date, most of the reported cases of NTS have been diagnosed during the postoperative follow‐up period. Herein, we report a case of NTS that occurred during preoperative neoadjuvant chemotherapy after EUS‐FNA for resectable pancreatic cancer. The patient underwent transgastric EUS‐FNA for a pancreatic tail tumor. He was diagnosed as having resectable pancreatic cancer and received preoperative neoadjuvant chemotherapy. After completion of the chemotherapy, computed tomography showed a thick‐walled cyst‐like structure appearing between the pancreas and the gastric wall. Combined resection revealed adenocarcinoma invasion into the cyst‐like structure. Based on the clinical course, and surgical and pathological findings, the condition was diagnosed as NTS. It is thus crucial that after EUS‐FNA, a detailed review of the imaging findings be conducted in the preoperative period. If adhesions between the stomach and the pancreas are observed after transgastric EUS‐FNA, combined resection of the gastric wall should be considered.

Gastric intramural metastasis caused by needle tract seeding after preoperative fine needle aspiration for pancreatic body cancer subsequently resected by total pancreatectomy: a case report and literature review

BACKGROUND

Recently, there has been an increase in the number of reports of needle tract seeding (NTS) of tumor cells after a biopsy as one of the adverse events related to endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA). In most of the previously reported cases of NTS in pancreatic cancer, distal pancreatectomy was performed as the initial surgery, following which metachronous metastasis was discovered in the gastric wall, whose localization matched the puncture route of the EUS-FNA. We report a case of early metastasis from pancreatic cancer in the gastric wall, which was postulated to be caused by NTS. Our patient underwent a total pancreatectomy (TP), and the NTS was resected synchronously.

CASE PRESENTATION

A 70-year-old woman with a diagnosis of pancreatic head-body-tail cancer presented to our department for surgery. Transgastric EUS-FNA and biopsy established the histological diagnosis in her case. We administered neoadjuvant chemotherapy (NAC) to the patient and performed a TP. Histopathological and immunohistochemical examination subsequently confirmed the diagnosis of pT3N1aM1 pancreatic adenocarcinoma and its gastric metastasis, which was caused by NTS. It is postulated that the tumor cells of NTS had progressed to develop the metastatic lesion in the gastric wall during the NAC period. This was also resected during the initial surgery. The patient developed an early postoperative recurrence in the peritoneum 8 months after the surgery.

CONCLUSION

In pancreatic head cancer cases, the puncture route is often included in the resection area of radical surgery, and NTS is seldom considered as a potential clinical problem. However, NTS can progress rapidly and may be associated with early recurrence of malignancy. Therefore, when transgastrointestinal puncture is performed for the diagnosis of pancreatic cancer, the treatment strategy should be established considering the potential development of NTS.

Detection of pancreatic cancer with two- and three-dimensional radiomic analysis in a nationwide population-based real-world dataset

BACKGROUND

CT is the major detection tool for pancreatic cancer (PC). However, approximately 40% of PCs < 2 cm are missed on CT, underscoring a pressing need for tools to supplement radiologist interpretation.

METHODS

Contrast-enhanced CT studies of 546 patients with pancreatic adenocarcinoma diagnosed by histology/cytology between January 2005 and December 2019 and 733 CT studies of controls with normal pancreas obtained between the same period in a tertiary referral center were retrospectively collected for developing an automatic end-to-end computer-aided detection (CAD) tool for PC using two-dimensional (2D) and three-dimensional (3D) radiomic analysis with machine learning. The CAD tool was tested in a nationwide dataset comprising 1,477 CT studies (671 PCs, 806 controls) obtained from institutions throughout Taiwan.

RESULTS

The CAD tool achieved 0.918 (95% CI, 0.895-0.938) sensitivity and 0.822 (95% CI, 0.794-0.848) specificity in differentiating between studies with and without PC (area under curve 0.947, 95% CI, 0.936-0.958), with 0.707 (95% CI, 0.602-0.797) sensitivity for tumors < 2 cm. The positive and negative likelihood ratios of PC were 5.17 (95% CI, 4.45-6.01) and 0.10 (95% CI, 0.08-0.13), respectively. Where high specificity is needed, using 2D and 3D analyses in series yielded 0.952 (95% CI, 0.934-0.965) specificity with a sensitivity of 0.742 (95% CI, 0.707-0.775), whereas using 2D and 3D analyses in parallel to maximize sensitivity yielded 0.915 (95% CI, 0.891-0.935) sensitivity at a specificity of 0.791 (95% CI, 0.762-0.819).

CONCLUSIONS

The high accuracy and robustness of the CAD tool supported its potential for enhancing the detection of PC.

Needle Tract Seeding after Endoscopic Ultrasound Tissue Acquisition of Pancreatic Lesions: A Systematic Review and Meta-Analysis

There is limited evidence on the incidence of needle tract seeding (NTS) in patients undergoing endoscopic ultrasound (EUS) tissue acquisition (TA) of pancreatic lesions. This meta-analysis aimed to assess the incidence of NTS after EUS-TA. With a search of the literature up until April 2022, we identified 10 studies (13,238 patients) assessing NTS incidences in patients undergoing EUS-TA. The primary outcome was NTS incidence. The secondary outcome was a comparison in terms of peritoneal carcinomatosis incidence between patients who underwent EUS-TA and non-sampled patients. Results were expressed as pooled rates or odds ratio (OR) and 95% confidence intervals (CI). The pooled rate of NTS was 0.3% (95% CI 0.2-0.4%), with no evidence of heterogeneity (I2 = 0%). Subgroup analysis based on the type of sampled lesion confirmed this finding both in patients with pancreatic adenocarcinoma (0.4%, 0.2-0.6%) and in patients with cystic pancreatic lesions (0.3%, 0.1-0.5%). No difference in terms of metachronous peritoneal dissemination was observed between patients who underwent EUS-TA and non-sampled patients (OR 1.02, 0.72-1.46; p = 0.31), with evidence of low heterogeneity (I2 = 16%). Rates of NTS after EUS-TA are very low; therefore, EUS-TA could be safely performed in a pre-operative setting.

Diagnostic Dilemma of Biliopancreatic Contrast-Enhanced Harmonic Endoscopic Ultrasonography

Background: The utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) alone in the biliopancreatic region appears to be limited because it is highly dependent on the experience and skill of the endoscopist. Therefore, the present study aimed to validate the efficacy of CH-EUS in clinical practice. Methods: Between January 2018 and March 2019, 301 consecutive patients who underwent CH-EUS were prospectively enrolled in this study. The diagnostic performance of CH-EUS was compared with that of dynamic computed tomography (CT), magnetic resonance imaging (MRI), and all combinations (i.e., CH-EUS, dynamic CT, and MRI) using a Bonferroni correction. A multiple logistic regression analysis was performed to extract each disease that allowed the CH-EUS diagnosis to be consistent with the final diagnosis. Results: In multiple comparisons of diagnostic performance, no significant differences were observed among dynamic CT, MRI, and CH-EUS (p = 1.00), but the diagnostic performance was significantly higher when all modalities were combined (p < 0.001). Moreover, only intraductal papillary mucinous neoplasm comprising adenoma or carcinoma (IPMN, n = 161) showed significance with respect to the agreement with the final diagnosis (p = 0.006). Conclusions: Our results showed that CH-EUS-based diagnosis of IPMN may be possible in clinical practice. On the contrary, to accurately diagnose biliopancreatic diseases other than IPMN, comprehensive diagnosis using multiple modalities may be necessary, rather than relying on CH-EUS alone.

Tumor Location in the Head/Uncinate Process and Presence of Fibrosis Impair the Adequacy of Endoscopic Ultrasound-Guided Tissue Acquisition of Solid Pancreatic Tumors

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) of solid pancreatic tumors shows optimal specificity despite fair sensitivity, with an overall suboptimal diagnostic yield. We aim to quantify the adequacy and accuracy of EUS-TA and assess predictive factors for success, focusing on the presence and degree of specimen fibrosis. All consecutive EUS-TA procedures were retrieved, and the specimens were graded for sample adequacy and fibrosis. The results were evaluated according to patients' and tumor characteristics and the EUS-TA technique. In total, 407 patients (59% male, 70 [63-77] year old) were included; sample adequacy and diagnostic accuracy were 90.2% and 94.7%, respectively. Fibrosis was significantly more represented in tumors located in the head/uncinate process (p = 0.001). Tumor location in the head/uncinate (OR 0.37 [0.14-0.99]), number of needle passes ≥ 3 (OR 4.53 [2.22-9.28]), and the use of cell block (OR 8.82 [3.23-23.8]) were independently related to adequacy. Severe fibrosis was independently related to false negative results (OR 8.37 [2.33-30.0]). Pancreatic tumors located in the head/uncinate process showed higher fibrosis, resulting in EUS-TA with lower sample adequacy and diagnostic accuracy. We maintain that three or more needle passes and cell block should be done to increase the diagnostic yield.

Pancreatic neuroendocrine carcinoma with unique morphological features mimicking intraductal papillary mucinous carcinoma: A case report

Background

Pancreatic neuroendocrine carcinoma (PanNEC) is a rare disease entity with rapid progression and poor prognosis. Here, we report a PanNEC case with unique morphological features mimicking intraductal papillary mucinous carcinoma.

Case presentation

A 69-year-old Japanese man was referred to our hospital for further evaluation of weight loss and deterioration of diabetes mellitus. Contrast-enhanced computed tomography showed a solid and cystic mass with hypo-enhancement at the tail of the pancreas. The main pancreatic duct (MPD) was diffusely dilated without obstruction, accompanied by marked parenchymal atrophy. Multiple peritoneal and omental nodules were observed, suggesting tumor dissemination. Endoscopic retrograde cholangiopancreatography revealed that the mass correlated with the dilated MPD. During pancreatography, a large amount of mucus was extruded from the pancreatic orifice of the ampulla. Based on these imaging findings, intraductal papillary mucinous carcinoma was suspected. Per-oral pancreatoscopy (POPS)-guided tumor biopsies were conducted for the lesion's solid components. Histopathological examination of the biopsied material confirmed small-cell-type PanNEC with a Ki-67 labeling index of 90%. Due to his condition's rapid decline, the patient was given the best supportive care and died 28 days after diagnosis.

Conclusion

Although rare, PanNEC, which correlates with the MPD and is accompanied by marked dilation of the MPD, does exist as one phenotype. In such cases, POPS-guided biopsy could be a useful diagnostic modality.

A nomogram for predicting survival in patients with advanced (stage III/IV) pancreatic body tail cancer: a SEER-based study

OBJECTIVE

Pancreatic body tail carcinoma (PBTC) is a relatively few pancreatic cancer in clinical practice, and its specific clinicopathological features and prognosis have not been fully described. In this study, we aimed to create a nomogram to predict the overall survival (OS) of patients with advanced PBTC.

METHODS

We extracted clinical and related prognostic data of advanced PBTC patients from 2000 to 2018 from the Surveillance, Epidemiology, and End Results database. Independent prognostic factors were selected using univariate and multivariate Cox analyses, and a nomogram was constructed using R software. The C-index, area under the curve (AUC) of receiver operating characteristic curves, calibration curves, and decision curve analysis (DCA) were used to assess the clinical utility of the nomogram. Finally, OS was assessed using the Kaplan-Meier method.

RESULTS

A total of 1256 patients with advanced PBTC were eventually included in this study. Age, grade, N stage, M stage, surgery, and chemotherapy were identified as independent risk factors using univariate and multivariate Cox regression analyses (p < 0.05). In the training cohort, the calibration index of the nomogram was 0.709, while the AUC values of the nomogram, age, grade, N stage, M stage, surgery, and chemotherapy were 0.777, 0.562, 0.621, 0.5, 0.576, 0.632, and 0.323, respectively. Meanwhile, in the validation cohort, the AUC values of the nomogram, age, grade, N stage, M stage, surgery, and chemotherapy were 0.772, 0.551, 0.629, 0.534, 0.577, 0.606, and 0.639, respectively. Good agreement of the model in the training and validation cohorts was demonstrated in the calibration and DCA curves. Univariate survival analysis showed a statistically significant effect of age, grade, M stage, and surgery on prognosis (p < 0.05).

CONCLUSION

Age, grade, M stage, and surgery were independently associated with OS, and the established nomogram was a visual tool to effectively predict OS in advanced PBTC patients.

Needle tract seeding after endoscopic ultrasound-guided tissue acquisition of pancreatic tumors: A nationwide survey in Japan

OBJECTIVES

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) plays a crucial role in the diagnosis of pancreatic tumors. The present study aimed to investigate the current status of needle tract seeding (NTS) after EUS-TA of pancreatic tumors based on a nationwide survey in Japan.

METHODS

Patients who underwent surgical resection of primary pancreatic tumors after EUS-TA performed between April 2010 and March 2018 were surveyed. The incidence rates of NTS were determined, and compared in patients with pancreatic ductal adenocarcinomas (PDACs) and other tumors, and in patients who underwent transgastric and transduodenal EUS-TA of PDACs. The detailed features and prognosis of patients with NTS were also assessed.

RESULTS

A total of 12,109 patients underwent surgical resection of primary pancreatic tumors after EUS-TA. The overall incidence rate of NTS was 0.330%, and the NTS rate was significantly higher in patients with PDAC than in those with other tumors (0.409% vs. 0.071%, P=0.004). NTS was observed in 0.857% of patients who underwent transgastric EUS-TA, but in none of those who underwent transduodenal EUS-TA. Of the patients with NTS of PDACs, the median time from EUS-TA to occurrence of NTS and median patient survival were 19.3 and 44.7 months, respectively, with 97.4% of NTS located in the gastric wall and 65.8% of NTS resected. The patient survival was significantly longer in patients who underwent NTS resection than in those without NTS resection (P=0.037).

CONCLUSIONS

NTS appeared only after transgastric not after transduodenal EUS-TA. Careful follow-up provides an opportunity to remove localized NTS lesions by gastrectomy.

Application of Proteomics in Pancreatic Ductal Adenocarcinoma Biomarker Investigations: A Review

Pancreatic ductal adenocarcinoma (PDAC), a highly aggressive malignancy with a poor prognosis is usually detected at the advanced stage of the disease. The only US Food and Drug Administration-approved biomarker that is available for PDAC, CA 19-9, is most useful in monitoring treatment response among PDAC patients rather than for early detection. Moreover, when CA 19-9 is solely used for diagnostic purposes, it has only a recorded sensitivity of 79% and specificity of 82% in symptomatic individuals. Therefore, there is an urgent need to identify reliable biomarkers for diagnosis (specifically for the early diagnosis), ascertain prognosis as well as to monitor treatment response and tumour recurrence of PDAC. In recent years, proteomic technologies are growing exponentially at an accelerated rate for a wide range of applications in cancer research. In this review, we discussed the current status of biomarker research for PDAC using various proteomic technologies. This review will explore the potential perspective for understanding and identifying the unique alterations in protein expressions that could prove beneficial in discovering new robust biomarkers to detect PDAC at an early stage, ascertain prognosis of patients with the disease in addition to monitoring treatment response and tumour recurrence of patients.

The Role of MRI Pancreatic Protocol in Assessing Response to Neoadjuvant Therapy for Patients With Borderline Resectable Pancreatic Cancer

BACKGROUND

Borderline Resectable Pancreatic Cancer (BRPC) remains a unique entity that is difficult to categorize due to variance in definitions and the small number of patients. The ultimate goal is to achieve a free resection (R0) after a favorable response to neoadjuvant therapy that is somewhat difficult to assess by current radiological parameters.

AIM

To evaluate the role of Magnetic Resonance Imaging (MRI) pancreatic protocol, including Diffusion-Weighted Imaging (DWI), in patients with BRPC receiving neoadjuvant therapy, and further compare it to RECIST criteria and outcome.

METHODS

Histologically confirmed BRPC patients were prospectively included. DWI-MRI was performed pre- and post-therapy. Clinical characteristics with ensuing operability were recorded and correlated to radiological RECIST/apparent diffusion coefficient (ADC) change, preoperative therapy administrated, surgical resection status, and survival.

RESULTS

Out of 30 BRPC cases, only 11 (36.7%) ultimately underwent pancreaticoduodenectomy. Attaining a stationary or stable disease via ADC/RECIST was achieved in the majority of cases (60%/53.3% respectively). Of the 12 patients (40%) who achieved a regression by ADC, 11 underwent surgery with an R0 status. These surgical cases showed variable RECIST responses (PR=5, SD=4, PD=3). Responders by ADC to neoadjuvant therapy were significantly associated to presenting with abdominal pain (p =0.07), a decline in post-therapy CA19-9 (p<0.001), going through surgery (p<0.001), and even achieving better survival (p<0.001 vs. 0.66).

CONCLUSION

DWI-MRI ADC picked up patients most likely to undergo a successful operative procedure better than traditional RECIST criteria. An algorithm incorporating novel radiological advances with CA19-9 deserves further assessment in future studies.