Impact of sarcopenia on biliary drainage during neoadjuvant therapy for pancreatic cancer.

BACKGROUND/AIMS: Since the usefulness of neoadjuvant chemo(radiation) therapy (NAT) for pancreatic cancer has been demonstrated, recurrent biliary obstruction (RBO) in patients with pancreatic cancer with a fully covered self-expandable metal stent (FCSEMS) during NAT is expected to increase. This study investigated the impact of sarcopenia on RBO in this setting. METHODS: Patients were divided into normal and low skeletal muscle index (SMI) groups and retrospectively analyzed. Patient characteristics, overall survival, time to RBO (TRBO), stent-related adverse events, and postoperative complications were compared between the two groups. A Cox proportional hazard model was used to identify the risk factors for short TRBO. RESULTS: A few significant differences were observed in patient characteristics, overall survival, stent-related adverse events, and postoperative complications between 38 patients in the normal SMI group and 17 in the low SMI group. The median TRBO was not reached in the normal SMI group and was 112 days in the low SMI group (p=0.004). In multivariate analysis, low SMI was the only risk factor for short TRBO, with a hazard ratio of 5.707 (95% confidence interval, 1.148-28.381; p=0.033). CONCLUSION: Sarcopenia was identified as an independent risk factor for RBO in patients with pancreatic cancer with FCSEMS during NAT.

Randomized trial comparing 15 vs 5 actuations per pass during endoscopic ultrasound-guided fine-needle biopsy for specimen acquisition of solid pancreatic lesions.

BACKGROUND AND AIM: There is currently no established number of actuations (to-and-fro movements) per pass during endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). This study aimed to compare 15 vs 5 actuations in terms of adequate specimen acquisition of solid pancreatic lesions. METHODS: In this prospective, randomized, crossover, noninferiority, single-center study, eligible patients underwent EUS-FNB using a 22-G Franseen needle with both 15 and 5 actuations per pass, performed in a randomized order, from October 2020 to December 2021. The acquired specimens from each pass were separately evaluated. The primary outcome was the accuracy of the histological diagnosis per pass. The noninferiority margin was set as 15%. RESULTS: Data from 85 patients were analyzed, revealing pancreatic cancer in 73 patients. The accuracy of the histological diagnosis in the 15 and 5 actuations groups was 83.5% (71/85) and 77.7% (66/85), respectively. The difference was -5.8% (95% confidence interval -15.6-3.4), which does not indicate noninferiority of the five actuations group. Among the secondary outcomes, the 15 actuations group was significantly superior to the five actuations group in terms of the obtained core tissues (1.88 [interquartile range 0.89-3.64] mm2 vs 1.66 [0.83-2.71] mm2 [P = 0.031]) and subjective evaluation of cytology specimens for pancreatic cancer (69.0% vs. 31.0%, P = 0.005). CONCLUSIONS: The noninferiority of five actuations in the accuracy of the histological diagnosis was not confirmed, and 15 actuations are preferred during EUS-FNB for solid pancreatic lesions.

The role of EUS elastography-guided fine needle biopsy in the histological diagnosis of solid pancreatic lesions: a prospective exploratory study.

This study aimed to evaluate the feasibility and efficacy of Endoscopic ultrasound elastography-guided fine needle biopsy (EUS-EG-FNB) for the diagnosis of pancreatic mass lesions. EUS-EG images were classified into heterogeneous and homogeneous groups. For the heterogeneous group, EUS-FNB was separately performed in both hard areas and soft areas. Only samples obtained during the first two passes (hard/soft areas) were used to compare the diagnostic accuracy as well as the quality and quantity of the specimens. We investigated the association of EUS-EG findings using strain histogram analysis with the histological findings. Fifty-five patients were enrolled including 25 patients with heterogeneous group. The homogeneous group had significantly lower mean strain value (hard) lesions. The adequate sampling rates from hard and soft areas were 88 and 92%, respectively (P = 0.6374). Comparison of the diagnostic accuracy and the quality and quantity of the histological core between hard and soft areas showed no significant differences. In pancreatic adenocarcinoma cases, the proportion of fibrous stroma in the core tissue was significantly correlated with the elasticity of the region. (R2 = 0.1226: P = 0.0022) EUS-EG may reflect tissue composition in pancreatic tumors, however, EUS-EG did not affect either the quality and quantity of the tissues obtained.Clinical Trial Registry No: UMIN-000033073.

Good and Bad Stroma in Pancreatic Cancer: Relevance of Functional States of Cancer-Associated Fibroblasts.

A well-known feature of human pancreatic ductal adenocarcinoma (PDAC) is the extensive proliferation of cancer-associated fibroblasts (CAFs) and highly fibrotic stroma. Recent evidence, based mainly on single-cell analyses, has identified various subsets of CAFs in PDAC mouse models. However, we do not know how these CAF subsets are involved in the progression and drug resistance of human PDAC. Additionally, it remains unclear whether these diverse CAFs have distinct origins and are indicators of genuinely distinct CAF lineages or reflect different states of the same CAFs depending on the tumor microenvironment. Interestingly, recent preclinical studies have started to characterize the nature of cancer-restraining CAFs and have identified their markers Meflin and collagen type I alpha 1. These studies have led to the development of strategies to induce changes in CAF phenotypes using chemical reagents or recombinant viruses, and some of them have been tested in clinical studies. These strategies have the unique potential to convert the so-called bad stroma to good stroma and may also have therapeutic implications for non-cancer diseases such as fibrotic diseases. Together with recently developed sophisticated strategies that specifically target distinct CAF subsets via adoptive cell transfer therapy, vaccination, and antibody-drug conjugates, any future findings arising from these clinical efforts may expand our understanding of the significance of CAF diversity in human PDAC.

Pharmacologic conversion of cancer-associated fibroblasts from a protumor phenotype to an antitumor phenotype improves the sensitivity of pancreatic cancer to chemotherapeutics.

Previous therapeutic attempts to deplete cancer-associated fibroblasts (CAFs) or inhibit their proliferation in pancreatic ductal adenocarcinoma (PDAC) were not successful in mice or patients. Thus, CAFs may be tumor suppressive or heterogeneous, with distinct cancer-restraining and -promoting CAFs (rCAFs and pCAFs, respectively). Here, we showed that induced expression of the glycosylphosphatidylinositol-anchored protein Meflin, a rCAF-specific marker, in CAFs by genetic and pharmacological approaches improved the chemosensitivity of mouse PDAC. A chemical library screen identified Am80, a synthetic, nonnatural retinoid, as a reagent that effectively induced Meflin expression in CAFs. Am80 administration improved the sensitivity of PDAC to chemotherapeutics, accompanied by increases in tumor vessel area and intratumoral drug delivery. Mechanistically, Meflin was involved in the suppression of tissue stiffening by interacting with lysyl oxidase to inhibit its collagen crosslinking activity. These data suggested that modulation of CAF heterogeneity may represent a strategy for PDAC treatment.

Differentiation Between Solid Pseudopapillary Neoplasm of the Pancreas and Nonfunctional Pancreatic Neuroendocrine Neoplasm Using Endoscopic Ultrasound.

OBJECTIVES: We investigated the utility of endoscopic ultrasound (EUS) for differentiating between solid pseudopapillary neoplasm of the pancreas (SPN) and pancreatic neuroendocrine neoplasm (PanNEN). METHODS: A retrospective analysis was performed on 29 and 77 consecutive patients with pathologically proven SPN and nonfunctional PanNEN. In patients who underwent contrast-enhanced harmonic EUS (CH-EUS), lesions were classified into 3 vascular patterns (hypoechoic/isoechoic/hyperechoic), and the presence of "the alveolus nest sign," which we previously reported as a characteristic feature of SPN on CH-EUS, was also assessed. RESULTS: Conventional EUS findings showed that calcification echoes were significantly more frequent in SPN lesions than in PanNEN lesions (19/29 [66%] vs 21/77 [27%], P = 0.001) as was internal isoechogenicity or hyperechogenicity (10/29 [34%] vs 11/77 [14%], P = 0.029). Contrast-enhanced harmonic EUS findings showed that SPN lesions more frequently had the isoechoic or hypoechoic vascular pattern, and significantly more frequently had the alveolus nest sign (18/25 [72%] vs 4/60 [7%], P < 0.001). In a multivariate analysis, the presence of the alveolus nest sign contributed the most to the SPN diagnosis (odds ratio, 70; 95% confidence interval, 6.2-786). CONCLUSIONS: Endoscopic ultrasound, particularly the presence of the alveolus nest sign on CH-EUS, is useful for differentiating SPN from PanNEN.

Comparison of outcomes between secondary fully covered and uncovered self-expandable metal stents in the treatment of recurrent biliary obstruction of pancreatic cancer.

BACKGROUND: The overall survival (OS) of pancreatic cancer (PC) has been prolonged by advances in chemotherapy, and the number of cases of recurrent biliary obstruction (RBO) after self-expandable metal stent (SEMS) placement is expected to increase. We herein compared outcomes between secondary fully covered SEMS (FC) and uncovered SEMS (UC) for RBO of PC with FC placed as the 1st SEMS. METHODS: Between May 2010 and March 2021, 62 PC patients who underwent SEMS exchange to FC (n = 34) or UC (n = 28) for RBO were retrospectively analyzed. Patient characteristics, OS, time to RBO (TRBO), and stent-related adverse events were compared between the FC and UC groups. Cox's proportional hazard model was used to identify risk factors for RBO with the 2nd SEMS. RESULTS: There was a significant difference between the FC and UC groups only in the 2nd SEMS diameter. Median OS and TRBO were 195 and 238 days in FC patients and 306 and 455 days in UC patients, respectively, with no significant differences between the two groups. No significant differences were observed in the stent-related adverse event rate. In multivariate analyses, only the 2nd SEMS diameter was significant (P = 0.009). Median TRBO were 455, 238, and 103 days in 10-mm UC, 10-mm FC, and 8-mm UC patients, with 10-mm UC patients having significantly longer TRBO than 10-mm FC and 8-mm UC patients (P = 0.020 and 0.001). CONCLUSION: SEMS exchange to 10-mm UC may be appropriate for RBO of PC with FC as the 1st SEMS.

Usefulness of Macroscopic On-Site Evaluation Using a Stereomicroscope during EUS-FNB for Diagnosing Solid Pancreatic Lesions.

METHODS: We reviewed a total of 60 consecutive patients who underwent both S-MOSE and rapid on-site cytopathological evaluation (ROSE) during EUS-FNB between July 2019 and October 2020, and the usefulness of S-MOSE in comparison with histology was evaluated. A 22-gauge Franseen needle was used to perform EUS-FNB in all patients, and only the specimens obtained by the first pass were evaluated. The final diagnosis was based on the surgical specimen or the clinical course consistent with the EUS-FNB results. RESULTS: The final diagnoses of the 60 patients included 45 patients with pancreatic ductal adenocarcinoma, 6 with autoimmune pancreatitis, 4 with mass-forming pancreatitis, 1 with pancreatic metastasis, 2 with pancreatic neuroendocrine tumor, and 2 with intraductal papillary mucinous carcinoma. The histological diagnostic accuracy of the first pass of EUS-FNB was 83.3% (50/60). The agreement between the S-MOSE and the histological diagnosis was 90% (54/60). The positive predictive value of S-MOSE for histological diagnosis was 90.7%, which can be an indicator of when to stop the EUS-FNB procedure. There were no immediate or delayed adverse events reported after the FNB based on the chart and medical visit history review. CONCLUSION: In the EUS-FNB of SPLs, S-MOSE can be an alternative to ROSE for specimen evaluation and has the potential to shorten the procedure time.

Differentiation between pancreatic metastases from renal cell carcinoma and pancreatic neuroendocrine neoplasm using endoscopic ultrasound.

OBJECTIVES: Pancreatic metastases from renal cell carcinoma (PRCC) often appear many years after treatment of the primary tumor, and differentiation from pancreatic neuroendocrine neoplasm (PanNEN) can be challenging due to their hypervascularity. Here, we investigated the utility of endoscopic ultrasound (EUS) for differentiation of these conditions. METHODS: A retrospective analysis was performed in 17 and 79 consecutive patients with pathologically proven PRCC and non-functional PanNEN who were examined by EUS. In cases examined by EUS elastography or contrast-enhanced harmonic EUS (CH-EUS), the lesions were classified as stiff or soft, or into three vascular patterns as hypoechoic, isoechoic, and hyperechoic. CH-EUS images at 20 s, 40 s, 60 s, 3 min and 5 min were used for evaluation. EUS images were independently reviewed by two readers who were blinded to all clinical information. RESULTS: The patients with PRCC were significantly older than those with PanNEN (median, 71 (range, 45-81) vs. 58 (22-76), P = 0.001) and more often had multiple tumors (6/17 (35%) vs. 7/79 (9%), P = 0.010). In EUS findings, PRCC lesions significantly more frequently had a marginal hypoechoic zone (MHZ) (11/17 (65%) vs. 27/79 (34%), P = 0.028), being classified as soft (12/13 (92%) vs. 26/58 (45%), P = 0.002), and showed sustained hyperechoic vascular patterns at 5 min (7/8 (88%) vs. 4/59 (7%), P < 0.001) compared to PanNEN lesions. CONCLUSIONS: The presence of a MHZ, a soft lesion, and a sustained hyperechoic vascular pattern in EUS may be useful for differentiating PRCC from PanNEN.

Endoscopic ultrasound elastography for small solid pancreatic lesions with or without main pancreatic duct dilatation.

BACKGROUND: /Objectives: Endoscopic ultrasound elastography (EUS-EG) is useful for diagnosis of small solid pancreatic lesions (SPLs), particularly in excluding pancreatic cancer (PC), but its dependence on main pancreatic duct dilatation (MPDD) has not been examined. We aimed to investigate EUS-EG for diagnosis of small SPLs with and without MPDD. METHODS: Patients with pathologically diagnosed SPLs of ≤20 mm were included and retrospectively analyzed. Using the blue:green ratio, an EUS-EG image was classified as blue-dominant, equivalent, or green-dominant. Using multiple EUS-EG images per patient, a lesion with a greater number of blue-dominant than green-dominant images was classified as stiff, and the others as soft. EUS-EG images in random order were judged by three raters. Considering stiff SPLs as PC, diagnostic performance of EUS-EG was examined for SPLs with and without MPDD. RESULTS: Of 126 cases analyzed, 65 (52%) were diagnosed as PC, and 63 (50%) had MPDD. A total of 1077 EUS-EG images were examined (kappa coefficient = 0.783). Lesions were classified as stiff in 91 cases and soft in 35 (kappa coefficient = 0.932). The ratio of stiff to soft lesions was significantly higher in PC than in non-PC (62:3 vs. 29:32, P < 0.001). The sensitivity, specificity, and negative predictive value of a stiff lesion with vs. without MPDD for diagnosis of PC were 94%, 23%, and 50% vs. 100%, 60%, and 100%, respectively. CONCLUSIONS: Using the EUS-EG stiffness classification for small SPLs, PC can be excluded with high confidence and concordance for a soft lesion without MPDD.

Diagnostic performance of endoscopic ultrasonography-guided elastography for solid pancreatic lesions: Shear-wave measurements versus strain elastography with histogram analysis.

BACKGROUND AND AIMS: Endoscopic ultrasound (EUS) elastography (EUS-EG) is a minimally invasive diagnostic method for evaluating tissue elasticity. The aim of this study was to evaluate the feasibility of newly developed EUS shear-wave measurement (EUS-SWM) and to compare diagnostic performance between EUS-SWM and the conventional strain elastography (SE) for the measurement of elasticity of solid pancreatic lesions (SPLs). METHODS: From December 2017 until August 2019, we retrospectively reviewed 64 consecutive cases with SPLs who underwent both EUS-SWM and SE. EUS-SWM was used to measure the shear-wave velocity, Vs (m/s), and the unique measurement reliability index, VsN (%), in the target lesion. SE images were assessed by strain histogram (SH) analysis, and the mean strain value of the elasticity index was measured. We evaluated the diagnostic performance of EUS-SWM and SE with SH to characterize the SPLs. RESULTS: The Vs (m/s) values of SPLs were 2.19 for pancreatic cancer (PC), 1.31 for pancreatic neuroendocrine neoplasm (PanNEN), 2.56 for mass-forming pancreatitis (MFP) and 1.58 for metastatic tumors. Vs showed no significant difference based on the disease. The mean strain values were 45.5 for PC, 47.3 for PanNEN, and 74.5 for MFP. In the comparison of tissue elasticity between PC and MFP, Vs showed no significant difference (P = 0.5687); however, the mean strain value was significantly lower in PC cases (45.4 vs 74.5: P = 0.0007). CONCLUSION: Endoscopic ultrasound SWM tended to be unstable for the measurement of elasticity of SPLs, and conventional SE with SH was superior for their characterization.

Can contrast-enhanced harmonic endoscopic ultrasonography accurately diagnose main pancreatic duct involvement in intraductal papillary mucinous neoplasms?

BACKGROUND: Main pancreatic duct (MPD) involvement in branch duct-type intraductal papillary mucinous neoplasms (BD-IPMNs) is a high risk finding for malignant IPMNs. However, discrepancies exist in the identification of MPD involvement between imaging findings and pathological diagnosis. The purpose of this study was to evaluate the diagnostic accuracy of preoperative assessment of MPD involvement in IPMNs using contrast-enhanced harmonic endoscopic ultrasound (CH-EUS). METHODS: This study involved 166 consecutive patients with BD-IPMNs who underwent surgical resection. CH-EUS was used to evaluate the MPD involvement according to the presence of mural nodules (MN) that advanced into the MPD or involved the MPD. The CH-EUS findings were compared with the pathological findings. Additionally, we analyzed the risk factors for malignant BD-IPMNs using multivariate analysis. RESULTS: A total of 77, 51, and 38 patients were pathologically diagnosed with low-grade or intermediate-grade dysplasia, high-grade dysplasia and invasive IPMNs, respectively. MPD involvement was diagnosed using CH-EUS (MPD-inv.-EUS) in 90 (54.2%) patients with a sensitivity, specificity and accuracy of 83.5%, 87.0% and 84.9%, respectively. The malignancy rate in patients with MPD-inv.-EUS was 71.6% (63/90). Multivariate logistic regression analysis showed that MPD-inv.-EUS (OR, 3.61; 95% CI:1.45-8.98), age (OR, 5.70; 95% CI: 1.47-22.2), cyst size (OR, 2.45; 95% CI:1.04-5.78) and MN size (OR, 7.05; 95% CI:2.48-20.0) were significant for malignant BD-IPMNs. CONCLUSIONS: MPD-inv.-EUS accurately represents the pathological involvement of IPMN and may be a useful predictor of malignant BD-IPMNs.

Risks and characteristics of pancreatic cancer and pancreatic relapse in autoimmune pancreatitis patients.

BACKGROUND AND AIM: We examined the differences in the risks and characteristics of pancreatic relapse (PR) and pancreatic cancer (PC) in patients with autoimmune pancreatitis (AIP). METHODS: We retrospectively reviewed 123 type 1 AIP patients with a median follow-up of 55 months (interquartile range, 27-98). The following items were evaluated: (i) cumulative relapse rates and risk factors, (ii) the incidence of PC, (iii) PR versus PC, and (iv) outcomes after the appearance of morphological changes in the pancreas (focal enlargement, apparent mass lesions, or main pancreatic duct dilation). RESULTS: (i) The cumulative PR rates were 1.7% within 1 year, 11.5% within 3 years, and 22.6% within 5 years. Lack of maintenance therapy, IgG4-related sclerosing cholangitis, and IgG4-related kidney disease were identified as independent predictors of relapse. (ii) Two patients (1.6%) were diagnosed with PC at 17 and 22 months after initial AIP diagnosis. (iii) Thirteen (59.1%) and four (18.2%) patients with PR had focal enlargement and main pancreatic duct dilation, respectively. The median CA19-9 level at initial diagnosis was significantly higher in PC patients (21 vs 220.5 U/mL, P = 0.014). (iv) Eight PR patients underwent endoscopic ultrasound-guided fine-needle aspiration, none of whom had malignant findings. PC was diagnosed by ultrasound-guided fine-needle aspiration in both cancer patients. CONCLUSIONS: Although the incidence of PC is low, it may mimic PR in AIP patients. Surveillance is important, and when morphological changes occur, biopsy and evaluation of serum IgG4 and CA19-9 levels (particularly if the levels were high before) should be considered.

[Autoimmune pancreatitis and IgG4-related hepatic inflammatory pseudotumor complicated by an impacted pancreatic stone at the major papilla during steroid treatment].

A 79-year-old male presented to our hospital with abdominal discomfort and was diagnosed with mass-forming pancreatitis. During follow-up, pancreatic stones and a hepatic mass with peripheral bile duct dilation were discovered. Serum IgG4 level was elevated, and a liver tumor biopsy revealed numerous IgG4-positive plasma cells and fibrosis. Chronic pancreatitis with the suspected involvement of autoimmune pancreatitis (AIP) and IgG4-related hepatic inflammatory pseudotumor (IgG4-HIP) was diagnosed. Therefore, a steroid treatment was initiated. However, 2 months later, the patient complained of epigastric pain that was found to be caused by an impacted pancreatic stone in the major papilla, which was endoscopically removed. Follow-up imaging findings confirmed the improvement in AIP and the dissolution of the IgG4-HIP.

A case of a patient with granulocyte-colony stimulating factor-producing pancreatic cancer who responded to nab-paclitaxel plus gemcitabine.

A 67-year-old male patient presented with an irregular mass involving the pancreatic body and tail with multiple liver/lymph node metastases. A biopsy indicated the presence of a poorly differentiated adenocarcinoma. Fever and increased white blood cell count, C-reactive protein levels, and granulocyte-colony stimulating factor (G-CSF) levels led to the diagnose of G-CSF-producing pancreatic cancer. The patient did not respond to FOLFIRINOX therapy (leucovorin, fluorouracil, irinotecan, and oxaliplatin), but nab-paclitaxel plus gemcitabine treatment was effective, resulting in tumor shrinkage and reduced G-CSF levels. After the fifth course of this therapy, exacerbation was noted, and the patient died of primary cancer 6 months after initiating the therapy. Here we report the case of this patient with G-CSF-producing pancreatic cancer who responded to chemotherapy.

Nab-paclitaxel+gemcitabine therapy for adenosquamous carcinoma of the pancreas: an autopsy case.

A male patient aged over 60 years presented with abdominal pain. A solid lesion measuring 7cm was detected in the pancreatic body and tail, along with periaortic lymphadenopathy. Endoscopic ultrasound-guided fine-needle aspiration suggested squamous cell carcinoma. Nab-paclitaxel+gemcitabine therapy was effective;however, tumor progression was noted after the completion of the fourth course, and the patient died from the primary cancer 7 months after the initial consultation. Autopsy led to a definitive diagnosis of adenosquamous carcinoma of the pancreas. Non-resected adenosquamous carcinoma of the pancreas treated by chemotherapy is rare. Here, we report such an example in the present case study.

Interleukin-25 expressed by brain capillary endothelial cells maintains blood-brain barrier function in a protein kinase Cepsilon-dependent manner.

Interleukin (IL)-25, a member of the IL-17 family of cytokines, is expressed in the brains of normal mice. However, the cellular source of IL-25 and its function in the brain remain to be elucidated. Here, we show that IL-25 plays an important role in preventing infiltration of the inflammatory cells into the central nervous system. Brain capillary endothelial cells (BCECs) express IL-25. However, it is down-regulated by inflammatory cytokines, including tumor necrosis factor (TNF)-alpha, IL-17, interferon-gamma, IL-1beta, and IL-6 in vitro, and is also reduced in active multiple sclerosis (MS) lesions and in the inflamed spinal cord of experimental autoimmune encephalomyelitis, an animal model of MS. Furthermore, IL-25 restores the reduced expression of tight junction proteins, occludin, junction adhesion molecule, and claudin-5, induced by TNF-alpha in BCECs and consequently repairs TNF-alpha-induced blood-brain barrier (BBB) permeability. IL-25 induces protein kinase Cepsilon (PKCepsilon) phosphorylation, and up-regulation of claudin-5 is suppressed by PKCepsilon inhibitor peptide in the IL-25-stimulated BCECs. These results suggest that IL-25 is produced by BCECs and protects against inflammatory cytokine-induced excessive BBB collapse through a PKCepsilon-dependent pathway. These novel functions of IL-25 in maintaining BBB integrity may help us understand the pathophysiology of inflammatory brain diseases such as MS.