Machine learning-based model for prediction and feature analysis of recurrence in pancreatic neuroendocrine tumors G1/G2.

BACKGROUND: Pancreatic neuroendocrine neoplasms (PanNENs) are a heterogeneous group of tumors. Although the prognosis of resected PanNENs is generally considered to be good, a relatively high recurrence rate has been reported. Given the scarcity of large-scale reports about PanNEN recurrence due to their rarity, we aimed to identify the predictors for recurrence in patients with resected PanNENs to improve prognosis. METHODS: We established a multicenter database of 573 patients with PanNENs, who underwent resection between January 1987 and July 2020 at 22 Japanese centers, mainly in the Kyushu region. We evaluated the clinical characteristics of 371 patients with localized non-functioning pancreatic neuroendocrine tumors (G1/G2). We also constructed a machine learning-based prediction model to analyze the important features to determine recurrence. RESULTS: Fifty-two patients experienced recurrence (14.0%) during the follow-up period, with the median time of recurrence being 33.7 months. The random survival forest (RSF) model showed better predictive performance than the Cox proportional hazards regression model in terms of the Harrell's C-index (0.841 vs. 0.820). The Ki-67 index, residual tumor, WHO grade, tumor size, and lymph node metastasis were the top five predictors in the RSF model; tumor size above 20 mm was the watershed with increased recurrence probability, whereas the 5-year disease-free survival rate decreased linearly as the Ki-67 index increased. CONCLUSIONS: Our study revealed the characteristics of resected PanNENs in real-world clinical practice. Machine learning techniques can be powerful analytical tools that provide new insights into the relationship between the Ki-67 index or tumor size and recurrence.

[Undistinguishable Cryptococcus-related granulomatous lesion from carcinoma in the tail of the pancreas: a case report].

Abdominal computed tomography revealed a 19×13mm delayed enhancing mass and dilation of the distal pancreatic duct in the head of the pancreas. Magnetic resonance cholangiopancreatography showed pancreatic duct stenosis in the tail of the pancreas. Endoscopic retrograde pancreatography revealed an abrupt interruption of the main pancreatic duct at the tail of the pancreas. We could not assess the distal side of the pancreatic stenosis due to the large extent of obstruction. The pancreatic head mass was diagnosed as adenocarcinoma using endoscopic ultrasound-fine needle aspiration biopsy. However, we could not determine whether the pancreatic duct stenosis in the tail of the pancreas was malignant. Nevertheless, we performed a total pancreatectomy with splenectomy. Histological examination showed poorly differentiated adenocarcinoma in the pancreatic head mass but the pancreatic duct stenosis in the tail of the pancreas was diagnosed as pancreatic granuloma caused by Cryptococcus. Fungal infections may reportedly promote the development of pancreatic cancer, as further suggested by this case of cryptococcal infection.

Discrepancy in the Ki67 labeling index of brain and orbital metastatic lesions from gastrointestinal neuroendocrine tumors: A case report.

Proliferative activity examined by Ki67 labeling index (LI) plays pivotal role for managing gastrointestinal neuroendocrine tumor (GI-NET). Few reports indicated the intra-patient heterogeneity of Ki67-LI among metastatic tumor sites. We report a case of brain and orbital metastases from GI-NET that showed discrepancy of the Ki67-LI. A 71 year-old woman who was diagnosed as GI-NET with liver and bone metastases and performed medical therapy, had headache, right exophthalmos, and pain of right eye and was referred to our department. Magnetic resonance image revealed that tumors in the left occipital region and right orbit. We diagnosed as metastatic brain and orbital tumors from GI-NET. Surgical removal of both symptomatic lesions was performed and the diagnosis was pathologically confirmed. Immunohistochemical studies revealed the discrepancy of the Ki67-LI of the lesions (brain tumor: 8% versus orbital tumor: 22%). Sampling of multiple metastatic sites may prevent underestimate tumor proliferative activity.

The feasibility of percutaneous transhepatic gallbladder aspiration for acute cholecystitis after self-expandable metallic stent placement for malignant biliary obstruction: a 10-year retrospective analysis in a single center.

BACKGROUND/AIMS: Patients with acute cholecystitis (AC) after metallic stent (MS) placement for malignant biliary obstruction (MBO) have a high surgical risk. We performed percutaneous transhepatic gallbladder aspiration (PTGBA) as the first treatment for AC. We aimed to identify the risk factors for AC after MS placement and the poor response factors of PTGBA. METHODS: We enrolled 401 patients who underwent MS placement for MBO between April 2011 and March 2020. The incidence of AC was 10.7%. Of these 43 patients, 37 underwent PTGBA as the first treatment. The patients' responses to PTGBA were divided into good and poor response groups. RESULTS: There were 20 patients in good response group and 17 patients in poor response group. Risk factors for cholecystitis after MS placement included cystic duct obstruction (p<0.001) and covered MS (p<0.001). Cystic duct obstruction (p=0.003) and uncovered MS (p=0.011) demonstrated significantly poor responses to PTGBA. Cystic duct obstruction is a risk factor for cholecystitis and poor response factor for PTGBA, whereas covered MS is a risk factor for cholecystitis and an uncovered MS is a poor response factor of PTGBA for cholecystitis. CONCLUSION: The onset and poor response factors of AC after MS placement were different between covered and uncovered MS. PTGBA can be a viable option for AC after MS placement, especially in patients with covered MS.

Comparing the Efficacy and Safety of Gemcitabine plus Nab-Paclitaxel versus Gemcitabine Alone in Older Adults with Unresectable Pancreatic Cancer.

BACKGROUND: Gemcitabine plus nab-paclitaxel (GnP) has been a standard treatment for unresectable pancreatic cancer (uPC); however, the current treatment status and usefulness in older adults with uPC remain unclear. Therefore, we aimed to investigate the patient background and compare the efficacy and safety of GnP versus other treatments in older adults with uPC. PATIENTS AND METHODS: In this prospective observational study, we enrolled 233 eligible patients aged ≥76 years with pathologically proven, clinically uPC, and no history of chemotherapy from 55 Japanese centers during September 2018-September 2019. The main endpoints were overall survival (OS), progression-free survival (PFS), and safety. Geriatric assessments were performed upon registration and after 3 months. To adjust for confounders, we conducted propensity score-matched analyses. RESULTS: GnP, gemcitabine alone (Gem), best supportive care, and other therapies were administered to 116, 72, 16, and 29 patients, respectively. In the propensity score-matched analysis, 42 patients each were selected from the GnP and Gem groups. The median OS was longer in the GnP group than in the Gem group (12.2 vs. 9.4 months; hazard ratio [HR], 0.65; 95% CI, 0.37-1.13). The median PFS was significantly longer in the GnP group than in the Gem group (9.2 vs. 3.7 months; HR, 0.38; 95% CI, 0.23-0.64). The incidence of severe adverse events was higher with GnP than with Gem; however, the difference was not significant. CONCLUSION: GnP is more efficacious than Gem in patients aged ≥76 years with uPC despite demonstrating a higher incidence of severe adverse events.

The Glasgow Prognostic Score and stricture site can predict prognosis after endoscopic duodenal stent placement for malignant gastric outlet obstruction.

Endoscopic duodenal stent (DS) placement for malignant gastric outlet obstruction (GOO) is rapidly increasing in clinical practice; however, the most suitable patient candidates for DS placement have not been determined. One hundred and thirty-five patients with GOO who underwent DS placement in three Japanese referral centers between January 2010 and October 2019 were retrospectively evaluated. Overall survival (OS) after DS placement, technical/clinical success rates, adverse events, and predictive factors affecting OS after DS placement were also analyzed. The median OS after DS placement of all patients was 81 (7-901) days. Technical and clinical success rates were 99.3% and 83.7%, respectively. The GOO Scoring System score significantly increased before and after DS placement (0.9 vs. 2.7, P < 0.001). The procedure-related complication rate was 6.0%. All 19 patients (14.1%) with stent occlusion underwent endoscopic re-intervention successfully. Multivariate analyses revealed chemotherapy after DS placement (P = 0.01), stricture site in D3 (distal part of the papilla) (P = 0.01), and a Glasgow Prognostic Score (GPS) of 0-1 before duodenal stent placement (P < 0.001) were factors significantly associated with prolonged OS. In conclusion, patients with a GPS of 0-1 and D3 stricture who are tolerant of chemotherapy are suitable candidates for DS placement.

Feasibility and Efficacy of Endoscopic Ultrasound-Guided Hepaticogastrostomy Without Dilation: A Propensity Score Matching Analysis.

BACKGROUND: Recently, endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) procedures have been gradually established; nonetheless, some adverse events (AEs) have been reported. Dilation procedures using a non-cautery or cautery device increase the incidence of AEs in EUS-HGS. AIMS: We evaluated EUS-HGS procedures without dilation and the factors associated with dilation. METHODS: We enrolled 79 patients who underwent EUS-HGS between July 2015 and March 2021 at two centers, 72 of whom had technical success (72/79, 91%). During the EUS-HGS procedures, we defined patients without dilation procedures as the dilation (-) group. We divided the patients into two groups: the dilation (+) (35 patients) and dilation (-) (37 patients) groups. We performed a propensity score matching analysis to adjust for confounding bias between the two groups. Multivariable logistic regression analysis was conducted to identify factors associated with dilation. RESULTS: There was no difference in clinical success rate between the dilation (+) and dilation (-) groups (91% vs. 95%, P = 0.545). The AE rate (P = 0.013) and long procedure time (P = 0.017) were significantly higher in the dilation (+) group than in the dilation (-) group before and after propensity score matching. Factors associated with dilation were plastic stent placement (odds ratio [OR], 6.96; 95% confidence interval [CI], 1.68-28.7; P = 0.007) and puncture angle of ≤ 90° (OR, 44.6; 95% CI, 5.1-390; P < 0.001). CONCLUSIONS: A dilation procedure in EUS-HGS may not always be necessary. However, patients with an angle of ≤ 90° between the needle and intrahepatic biliary tract or plastic stent deployment require dilation procedures.

Discrepancy in the Ki67 labeling index of brain and orbital metastatic lesions from gastrointestinal neuroendocrine tumors: A case report.

Proliferative activity examined by Ki67 labeling index (LI) plays pivotal role for managing gastrointestinal neuroendocrine tumor (GI-NET). Few reports indicated the intra-patient heterogeneity of Ki67-LI among metastatic tumor sites. We report a case of brain and orbital metastases from GI-NET that showed discrepancy of the Ki67-LI. A 71 year-old woman who was diagnosed as GI-NET with liver and bone metastases and performed medical therapy, had headache, right exophthalmos, and pain of right eye and was referred to our department. Magnetic resonance image revealed that tumors in the left occipital region and right orbit. We diagnosed as metastatic brain and orbital tumors from GI-NET. Surgical removal of both symptomatic lesions was performed and the diagnosis was pathologically confirmed. Immunohistochemical studies revealed the discrepancy of the Ki67-LI of the lesions (brain tumor: 8% versus orbital tumor: 22%). Sampling of multiple metastatic sites may prevent underestimate tumor proliferative activity.

nal-IRI+5-FU/LV versus 5-FU/LV in post-gemcitabine metastatic pancreatic cancer: Randomized phase 2 trial in Japanese patients.

BACKGROUND: In the NAPOLI-1 phase 3 trial, liposomal irinotecan (nal-IRI) +5-fluorouracil/leucovorin (5-FU/LV) significantly increased mPFS versus 5-FU/LV (3.1 vs. 1.5 months [unstratified HR = 0.56, p = 0.0001]) in patients with mPAC that progressed on prior gemcitabine-based therapy. This randomized phase 2 trial evaluated nal-IRI+5-FU/LV tolerability (Part 1), safety, and efficacy (Part 2; outcomes reported here) in Japanese patients with mPAC that progressed on gemcitabine-based therapy. METHODS: Patients were randomized 1:1 and stratified by KPS (70 and 80 vs. ≥90) and baseline albumin (≥4.0 g/dl vs. <4.0 g/dl). Primary endpoint was PFS; secondary endpoints were ORR, DCR, OS, TTF, CA19-9 response, and QoL. The ITT population comprised all randomized patients. RESULTS: Patient characteristics differed between nal-IRI+5-FU/LV (n = 40) and 5-FU/LV (n = 39) arms, including baseline hepatic lesions (63% vs. 51%), stage IV disease at diagnosis (78% vs. 51%), and post-study anticancer therapy (55% vs. 72%). Investigator-assessed mPFS increase with nal-IRI+5-FU/LV was clinically meaningful and statistically significant versus 5-FU/LV (2.7 vs. 1.5 months, HR = 0.60). Independently assessed mPFS showed similar trends (1.7 vs. 1.6 months, HR = 0.79). mOS was 6.3 months with nal-IRI+5-FU/LV and not reached with 5-FU/LV. ORR increased significantly with nal-IRI+5-FU/LV versus 5-FU/LV (18% vs. 0, rate difference 17.5). Commonly reported grade ≥3 treatment-emergent AEs were decreased neutrophil count (37% vs. 3%), decreased white blood cell count (20% vs. 0), and diarrhea (17% vs. 3%). CONCLUSIONS: In conclusion, clinically meaningful and statistically significant gains in investigator-assessed PFS and ORR were observed with nal-IRI+5-FU/LV versus 5-FU/LV in Japanese patients, with no new or unexpected safety signals. (Clinicaltrials.gov ID: NCT02697058).

A case of small cell neuroendocrine carcinoma of the ampulla of Vater.

BACKGROUND: Gastroenteric neuroendocrine carcinomas (NECs) account for 6.2% of gastroenteric neuroendocrine tumors (NETs), and only 1% or less of gastroenteric NETs occur in the ampulla of Vater (AoV). Clinical features of NEC of the AoV remain obscure. CASE PRESENTATION: A 65-year-old man visited a general practitioner because of jaundice, and an abdominal contrast-enhanced computed tomography scan revealed a tumor of 11 mm in diameter, which was enhanced in the arterial phase at the duodenal papilla, with dilation of the upstream bile duct. Gastrointestinal scope revealed an unexposed tumor of the AoV. Based on a biopsy of the site, a moderately differentiated tubular adenocarcinoma was suspected, and pancreatoduodenectomy was performed. Histopathological examination revealed dysplasia and highly proliferative small tumor cells, with solid and nodular formation at the AoV. Histological analysis showed a high mitotic count, and immunohistochemical staining revealed a Ki-67 index of 40-50% and cells positive for synaptophysin, chromogranin A, and p53. Small cell-type NEC was finally diagnosed. Four months post pancreatoduodenectomy, multiple liver metastases developed, and systemic chemotherapy was administered. Salvage liver resection for liver metastases was performed 14 months after the pancreatoduodenectomy. Unfortunately, multiple liver metastases developed 2 months after liver resection, and the patient died 18 months after the pancreatoduodenectomy. CONCLUSIONS: Neuroendocrine carcinoma originating from the bile duct is very rare; therefore, in this article, we provide a review of the literature and a case report.

[Massive biliary hemorrhage due to rupture of pseudoaneurysm after endoscopic biliary plastic stenting for pancreatic cancer].

A 51-year-old woman underwent endoscopic biliary drainage with a plastic stent for obstructive jaundice due to unresectable pancreatic head cancer. During chemotherapy following heavy ion therapy for the cancer, she presented with acute cholangitis and massive rectal bleeding. The massive hemorrhage was caused by rupture of the biliary duct due to a pseudoaneurysm in the right hepatic artery. The position of the aneurysm coincided with the liver-side end of the plastic stent. Sustained irritation of the arterial and bile duct walls by the stent was considered to have contributed to formation of the aneurysm.

Conversion surgery for initially unresectable carcinoma of the ampulla of Vater following pathological complete response to chemotherapy: a case report.

BACKGROUND: Carcinoma of the ampulla of Vater with distant metastases is regarded as unresectable. Systemic chemotherapy is basically the treatment of choice for such tumors. CASE PRESENTATION: A 68-year-old woman was referred to our hospital and diagnosed with carcinoma of the ampulla of Vater with lymph node and multiple liver metastases. She underwent systemic chemotherapy with a combination of gemcitabine and cisplatin. After 19 months of treatment, the primary tumor and liver metastases were difficult to detect on follow-up images. Shrinkage of the enlarged lymph nodes was also confirmed. Surgical resection was performed with curative intent after a multidisciplinary meeting. Pathological examination of the resected specimen showed no residual tumors. Systemic chemotherapy achieved a pathological complete response. The postoperative course was uneventful, and the patient remained free of recurrent disease at 10 months of follow-up. CONCLUSION: This case shows the possibility of conversion surgery after systemic chemotherapy for carcinoma of the ampulla of Vater.

Imaging features of undifferentiated carcinoma of the pancreas.

INTRODUCTION: The purpose of this retrospective study was to evaluate imaging features of undifferentiated carcinoma of the pancreas. METHODS: The study group included eight patients with surgically resected undifferentiated carcinoma of the pancreas. Multidetector-row computed tomography (MDCT, n = 8) and magnetic resonance imaging (MRI, n = 6) findings were retrospectively reviewed. RESULTS: On MDCT, all eight cases were hypovascular with upstream main pancreatic duct (MPD) dilatation, and only 1 showed exophytic growth. Five cases (62.5%) showed necrosis/cystic change, and calcification was observed in two cases (25%). Calcification reflected tumour osteoid components. On MRI, haemorrhage and hemosiderin were observed in 4 of 6 (66.7%) cases. In addition, tumour thrombus in the splenic vein (n = 1) and intraductal tumour growth in the MPD (n = 2) were pathologically identified, although imaging studies only revealed 1 of these latter cases. CONCLUSION: Undifferentiated carcinoma of the pancreas may present as a tumour with haemorrhagic necrosis. Coexistence of calcification, intraductal tumour growth in the MPD and tumour thrombus may support the imaging diagnosis of this entity.

CLEC3A, MMP7, and LCN2 as novel markers for predicting recurrence in resected G1 and G2 pancreatic neuroendocrine tumors.

Although the postoperative recurrence rate for pancreatic neuroendocrine tumors (PNETs) is reported to be 13.5%-30%, the paucity of valuable biomarkers to predict recurrence poses a problem for the early detection of relapse. Hence, this study aimed to identify new biomarkers to predict the recurrence of PNETs. We performed RNA sequencing (RNA-Seq) on RNA isolated from frozen primary tumors sampled from all localized G1/G2 PNETs resected curatively from 1998 to 2015 in our institution. We calculated differentially expressed genes (DEGs) in tumor with and without recurrence (≥3 years) for the propensity-matched cohort. Gene ontology analysis for the identified DEGs was also performed. Furthermore, we evaluated the expression levels of candidate genes as recurrence predictors via immunostaining. Comparison of transcriptional levels in tumors with and without recurrence identified 166 DEGs. Up- and downregulated genes with high significance in these tumors were mainly related to extracellular organization and cell adhesion, respectively. We observed the top three upregulated genes, C-type lectin domain family 3 member A (CLEC3A), matrix metalloproteinase-7 (MMP7), and lipocalin2 (LCN2) immunohistochemically and compared their levels in recurrent and nonrecurrent tumors. Significantly higher recurrence rate was shown in patients with positive expression of CLEC3A (P = 0.028), MMP7 (P = 0.003), and LCN2 (P = 0.040) than that with negative expression. We identified CLEC3A, MMP7, and LCN2 known to be associated with the phosphatidylinositol-3-kinase/Akt pathway, as potential novel markers to predict the postoperative recurrence of PNETs.

Relapse patterns and predictors of IgG4-related diseases involved with autoimmune pancreatitis: A single-center retrospective study of 115 patients.

OBJECTIVE: Autoimmune pancreatitis is an autoimmune disorder accompanied by clinicopathological manifestations that have been established as immunoglobulin (IgG)4-related diseases (IgG4-RD). Other IgG4-RD are often involved with autoimmune pancreatitis. They sometimes relapse despite a favorable response to steroid therapy. This study aimed to clarify the patterns and risk factors for extrapancreatic relapse. METHODS: We reviewed the data of 115 patients diagnosed with definite autoimmune pancreatitis type 1 and followed up for > 1 year. We analyzed two items: the timing and pattern of extrapancreatic relapse, and risk factors for relapse with three common manifestations: IgG4-related sclerosing cholangitis (SC), IgG4-related dacryoadenitis and sialadenitis (DS), and IgG4-related retroperitoneal fibrosis (RF). RESULTS: Remission was achieved in all patients, except one. The extrapancreatic relapse rates were 11.0%, 19.7%, and 40% within 3, 5, and 10 years, respectively. Of 26 patients with extrapancreatic relapse, nine (34.6%) relapsed with a new IgG4-RD. Based on multivariate analysis, the interval between symptom onset and steroid initiation, and the presence of RF at onset were significant risk factors for relapse with SC and RF, respectively. CONCLUSIONS: Our results indicate that they may be various extrapancreatic relapse patterns especially in autoimmune pancreatitis with other organ involvement. Patients with a delayed initiation of steroids or RF at onset should be carefully followed up as high-risk groups for SC and RF relapse.

Using CRISPR/Cas9 to Knock out Amylase in Acinar Cells Decreases Pancreatitis-Induced Autophagy.

Pancreatic cancer is a malignant neoplasm that originates from acinar cells. Acinar cells get reprogrammed to become duct cells, resulting in pancreatic cancer. Pancreatitis is an acinar cell inflammation, leading to "impaired autophagy flux". Pancreatitis promotes acinar-to-ductal transdifferentiation. Expression of amylase gets eliminated during the progression of pancreatic cancer. Amylase is considered as an acinar cell marker; however, its function in cells is not known. Thus, we investigated whether amylase affects the acinar cell autophagy and whether it plays any role in development of pancreatitis. Here, we knocked out ATG12 in a pancreatic cancer cells and acinar cells using CRISPR/Cas9. Autophagy inhibition led to an increase in the expression of duct cell markers and a simultaneous decrease in that of acinar cell markers. It also caused an increase in cell viability and changes in mitochondrial morphology. Next, we knocked out amylase in acinar cells. Amylase deficiency decreased autophagy induced by pancreatitis. Our results suggest that amylase controls pancreatitis-induced autophagy. We found that eliminating amylase expression contributes to pancreatic cancer etiology by decreasing autophagy. Furthermore, our results indicate that amylase plays a role in selective pancreatitis-induced autophagy of pancreatic enzyme vesicles.