Short-term serial circulating tumor DNA assessment predicts therapeutic efficacy for patients with advanced pancreatic cancer

PURPOSE

We investigated the potential clinical utility of short-term serial KRAS-mutated circulating cell-free tumor DNA (ctDNA) assessment for predicting therapeutic response in patients undergoing first-line chemotherapy for advanced pancreatic cancer.

METHODS

We collected 144 blood samples from 18 patients with locally advanced or metastatic cancer that were undergoing initial first-line chemotherapy of gemcitabine plus nab-paclitaxel (GEM plus nab-PTX). Analysis of KRAS-mutated ctDNA was quantified by digital droplet polymerase chain reaction (ddPCR) as mutant allele frequency (MAF). This study investigated pretreatment KRAS-mutated ctDNA status and ctDNA kinetics every few days (days 1, 3, 5 and 7) after initiation of chemotherapy and their potential as predictive indicators.

RESULTS

Of the 18 enrolled patients, an increase in KRAS-mutated ctDNA MAF values from day 0-7 after initiation of chemotherapy was significantly associated with disease progression (P < 0.001). Meanwhile, positive pretreatment ctDNA status (MAF ≥ 0.02%) (P = 0.585) and carbohydrate antigen 19-9 (CA19-9) values above the median (P = 0.266) were not associated with disease progression. In univariate analysis, this short-term increase in ctDNA MAF values (day 0-7) was found to be associated with significantly shorter progression free survival (PFS) (hazard ration [HR], 24.234; range, (2.761-212.686); P = 0.0002).

CONCLUSION

This short-term ctDNA kinetics assessment may provide predictive information to reflect real-time therapeutic response and lead to effective refinement of regimen in patients with advanced pancreatic cancer undergoing systemic chemotherapy.

An easy-to-implement, non-invasive head restraint method for monkey fMRI

Functional magnetic resonance imaging (fMRI) in behaving monkeys has a strong potential to bridge the gap between human neuroimaging and primate neurophysiology. In monkey fMRI, to restrain head movements, researchers usually surgically implant a plastic head-post on the skull. Although time-proven to be effective, this technique could create burdens for animals, including a risk of infection and discomfort. Furthermore, the presence of extraneous objects on the skull, such as bone screws and dental cement, adversely affects signals near the cortical surface. These side effects are undesirable in terms of both the practical aspect of efficient data collection and the spirit of "refinement" from the 3R's. Here, we demonstrate that a completely non-invasive fMRI scan in awake monkeys is possible by using a plastic head mask made to fit the skull of individual animals. In all of the three monkeys tested, longitudinal, quantitative assessment of head movements showed that the plastic mask has effectively suppressed head movements, and we were able to obtain reliable retinotopic BOLD signals in a standard retinotopic mapping task. The present, easy-to-make plastic mask has a strong potential to simplify fMRI experiments in awake monkeys, while giving data that is as good as or even better quality than that obtained with the conventional head-post method.

Utility of contrast-enhanced harmonic endoscopic ultrasonography for prediction of pathological response after neoadjuvant chemotherapy in patients with pancreatic cancer

OBJECTIVES

Contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) plays an important role in the diagnosis of pancreatic lesions. The aim of this study was to evaluate whether CH-EUS is useful for predicting the treatment efficacy of neoadjuvant chemotherapy (NAC) determined by pathological response.

METHODS

Patients who underwent CH-EUS before chemotherapy and surgical resection were divided into two groups according to poor (group-P) or rich tumor vascularity (group-R) determined by enhancement pattern on early- and late-phase CH-EUS. The pathological response to chemotherapy was categorized according to Evans' classification. Pathological analysis showing tumor cell destruction (>50 %) defined a good response.

RESULTS

Early-phase CH-EUS classified 44 patients into group-R and 50 into group-P, whereas late-phase CH-EUS classified 10 into group-R and 84 into group-P. Early-phase CH-EUS classification resulted in significantly higher numbers of patients with a good response in the rich group (n = 19) than in the poor group (n = 4; P = 0.0015). Multivariate analysis showed that assignment to the rich group was the strongest independent factor associated with chemosensitivity (P = 0.006, hazard ratio = 5.66, 95 % confidence interval: 1.17-19.27). In resectable patients, the enhancement pattern was the only independent factor associated with chemosensitivity (group-P vs. group-R, P = 0.003; HR [95 % CI], 14.59 [1.38-154.38]). Late-phase CH-EUS did not reveal a significant difference between group-P and group-R.

CONCLUSIONS

Evaluation of vascular pattern on CH-EUS could be useful for predicting the efficacy of NAC in patients with pancreatic cancer. The enhancement pattern on CH-EUS could be a one of the useful features for determining NAC indications in resectable pancreatic cancer patients.

Radiographic duodenal invasion is associated with poor prognosis and early recurrence in patients with pancreatic ductal adenocarcinoma

BACKGROUND

The prognostic impact of radiographic duodenal invasion (rDI) of pancreatic ductal adenocarcinoma (PDAC) has yet to be fully elucidated. This retrospective study aimed to investigate the prognostic and clinicopathological significance of rDI in patients with PDAC after pancreatoduodenectomy (PD).

MATERIALS AND METHODS

We retrospectively analyzed 223 consecutive patients with resectable (R) and borderline resectable (BR)-PDAC that underwent up-front PD between 2002 and 2018. rDI was assessed by preoperative multi-detector row computed tomography.

RESULTS

Ninety-three (42%) patients with PDAC had rDI, and all of them had pathological DI (pDI). The rDI(+) group had larger tumor size, BR-PDAC was more common, there was higher serum CA19-9 level, and microscopic lymphovascular invasion was more common than in the rDI(-) group. rDI was associated with significant reduction in overall survival (OS) (P < 0.001) and recurrence-free survival (RFS) (P < 0.001). In multivariate analysis, rDI was an independent prognostic factor in OS [hazard ratio (HR) = 0.52; 95% confidence interval (CI) 0.38-0.73, P < 0.001] and RFS [HR = 0.56; 95% CI 0.40-0.78, P = 0.001]. rDI was also an independent risk factor for early recurrence within 12 months [odds ratio (OR) = 0.36; 95% CI 0.18-0.73, P = 0.005]. rDI had positive correlation with liver recurrence (P = 0.024).

CONCLUSION

Biological aggressiveness of PDAC with rDI implies short OS and early recurrence with frequent liver metastasis. Aggressive perioperative chemotherapy is recommended to improve prognosis, especially for R-PDAC patients with rDI.

Insights from managing clinical issues in distal pancreatectomy with en bloc coeliac axis resection: experiences from 626 patients

BACKGROUND

Distal pancreatectomy with en bloc coeliac axis resection (DP-CAR) for pancreatic body cancer has been reported increasingly. However, its large-scale outcomes remain undocumented. This study aimed to evaluate DP-CAR volume and mortality, preoperative arterial embolization for ischaemic gastropathy, the oncological benefit for resectable tumours close to the bifurcation of the splenic artery and coeliac artery using propensity score matching, and prognostic factors in DP-CAR.

METHODS

In a multi-institutional analysis, 626 DP-CARs were analysed retrospectively and compared with 1325 distal pancreatectomies undertaken in the same interval.

RESULTS

Ninety-day mortality was observed in 7 of 21 high-volume centres (1 or more DP-CARs per year) and 1 of 41 low-volume centres (OR 20.00, 95 per cent c.i. 2.26 to 177.26). The incidence of ischaemic gastropathy was 19.2 per cent in the embolization group and 7.9 per cent in the no-embolization group (OR 2.77, 1.48 to 5.19). Propensity score matching analysis showed that median overall survival was 33.5 (95 per cent c.i. 27.4 to 42.0) months in the DP-CAR and 37.9 (32.8 to 53.3) months in the DP group. Multivariable analysis identified age at least 67 years (HR 1.40, 95 per cent c.i. 1.12 to 1.75), preoperative tumour size 30 mm or more (HR 1.42, 1.12 to 1.80), and preoperative carbohydrate antigen 19-9 level over 37 units/ml (HR 1.43, 1.11 to 1.83) as adverse prognostic factors.

CONCLUSION

DP-CAR can be performed safely in centres for general pancreatic surgery regardless of DP-CAR volume, and preoperative embolization may not be required. This procedure has no oncological advantage for resectable tumour close to the bifurcation of the splenic artery, and should be performed after appropriate patient selection.

Right posterior bile duct stricture after laparoscopic anterior sectionectomy with long right bile duct: A case report

Right anterior liver sectionectomy (RAS) is a complicated procedure with high incidences of postoperative complications. We report a case of right posterior bile duct (RPBD) stricture after laparoscopic RAS with discussion of the anatomical aspects. A 69-year-old Japanese man had solitary colorectal liver metastasis. A tumor was located near the root of the right anterior Glissonean pedicle. On postoperative day 6, he had cholangitis and imaging studies showed RPBD stricture. Symptoms disappeared following a course of antibiotics and the patient was discharged on postoperative day 21. The RBPD anatomy type of this patient was a supra-portal pattern with a long (18 mm) right biliary duct, which would be close to the right anterior Glissonean bifurcation. A stapling device might have caused its deformation and resulted in its stricture. As the RPBD has variant anatomy, we had to notice that there may be hazardous types for postoperative RPBD stricture.

Radiological Shape of the Tumor Predicts Progression and Survival in Resected Extrahepatic Cholangiocarcinoma

BACKGROUND

The histological features and radiological shape of extrahepatic cholangiocarcinoma (eCCA) have not been widely studied in relation to prognosis. Multi-detector computed tomography (MDCT) is thought to be useful in diagnosis of progress and tumor distribution; it can also show morphological differences (round, triangular, and square forms) at the tumoral obstruction sites. Histological types of eCCA may be revealed, with potential association with tumor growth and survival.

METHODS

We examined the distribution of tumor radiological shape subtypes on MDCT. The surgical outcomes of consecutive patients with eCCA who underwent macroscopic curative resection were reviewed.

RESULTS

CT subtypes in 109 patients were 62 triangular, 35 square, and 12 round. There were clear prognostic differences in long-term survival rates (P < 0.001); 5-year survival rates were 100% in round, 64% in triangular, and 19% in square types. There was no recurrence in any cases of round-type tumor at the site of obstruction. Depth of tumor invasion and rates of nodal involvement were significantly higher in triangular and square-type tumors than in round-type tumors. In papillary adenocarcinoma, radiological obstructions were round type in seven patients (78%) and triangular type in two patients (22%). In tubular adenocarcinoma, all round-type tumors were well differentiated, the ratio of square-type tumors increasing as the degree of differentiation decreased from "well" to "moderate," and "poor" respectively (23%, 39%, 57%; P = 0.033).

CONCLUSIONS

Tumor radiological shape predicts tumor progression, histological type, and survival in eCCA. This information may be helpful in preoperative radiological staging on MDCT.

Clinical practice guidelines for duodenal cancer 2021

Duodenal cancer is considered to be a small intestinal carcinoma in terms of clinicopathology. In Japan, there are no established treatment guidelines based on sufficient scientific evidence; therefore, in daily clinical practice, treatment is based on the experience of individual physicians. However, with advances in diagnostic modalities, it is anticipated that opportunities for its detection will increase in future. We developed guidelines for duodenal cancer because this disease is considered to have a high medical need from both healthcare providers and patients for appropriate management. These guidelines were developed for use in actual clinical practice for patients suspected of having non-ampullary duodenal epithelial malignancy and for patients diagnosed with non-ampullary duodenal epithelial malignancy. In this study, a practice algorithm was developed in accordance with the Minds Practice Guideline Development Manual 2017, and Clinical Questions were set for each area of epidemiology and diagnosis, endoscopic treatment, surgical treatment, and chemotherapy. A draft recommendation was developed through a literature search and systematic review, followed by a vote on the recommendations. We made decisions based on actual clinical practice such that the level of evidence would not be the sole determinant of the recommendation. This guideline is the most standard guideline as of the time of preparation. It is important to decide how to handle each case in consultation with patients and their family, the treating physician, and other medical personnel, considering the actual situation at the facility (and the characteristics of the patient).

Malignant potential and specific characteristics of pure main duct type intraductal papillary mucinous neoplasm

BACKGROUND

As the malignant potential of main duct (MD-) type intraductal papillary mucinous neoplasm (IPMN) has been discussed together with Mixed-type in most previous studies, the malignant potential of pure MD-type IPMN remains unclear. This study evaluated the specific characteristics and predictors of high-grade dysplasia (HGD) and invasive intraductal papillary mucinous carcinoma (IPMC) for pure MD-type IPMN.

METHODS

From 1,100 patients with IPMN, this study includes 387 patients that underwent surgery. We evaluated the specific characteristics of pure MD-type IPMN by comparing clinicopathological factors between MD-type (n = 79) and branch duct (BD-) type (n = 146) or Mixed-type IPMN (n = 162), and predictors of HGD/invasive IPMC in pure MD-type IPMN.

RESULTS

The rate of HGD/invasive IPMC was significantly higher in MD-type than in BD-type (70.9 vs. 48.6%, P = 0.001), although there was no difference between MD-type and Mixed-type IPMNs (P = 0.343). Recurrence-free survival (RFS) and disease-specific survival (DSS) of patients with MD-type were better than those of patients with Mixed-type (P = 0.008 and P = 0.009, respectively). There were no significant differences in RFS, overall survival, and DSS between patients with MD-type and patients with BD-type IPMNs. Multivariate analysis showed two independent predictors of HGD/invasive IPMC in MD-type IPMN; mural nodule height ≥5 mm (P = 0.025, odds ratio [OR]; 16.949) and carcinoembryonic antigen (CEA) level in the pancreatic juice obtained by preoperative endoscopic retrograde pancreatography ≥50 ng/ml (P = 0.039, OR; 9.091).

CONCLUSIONS

Measurement of mural nodule height and CEA in the pancreatic juice might be useful in determining surgical indication for pure MD-type IPMN, although further studies for confirmation are essential.

Pancreatectomy With Artery En-bloc Resection for Pancreatic Neck/Body Cancer: A Single-arm Pilot Study

BACKGROUND/AIM

The potential benefits of pancreatectomy with major arterial resection have been studied in the past, but findings remain controversial. Pancreatic neck/body cancer (PNBC) involving arteries frequently requires combined resection of the pancreas, artery and portal vein.

PATIENTS AND METHODS

Nine prospectively-registered consecutive patients with PNBC were enrolled, all underwent pancreatoduodenectomy with common hepatic artery en-bloc resection (PD-CHAR). We investigated the safety of PD-CHAR by blood flow evaluation with intraoperative indocyanine green fluorescence imaging in reconstructed vessels/organs.

RESULTS

Among patients who underwent PD-CHAR, there was no severe morbidity. Artery/portal vein combined resection and reconstruction was performed in all patients. Four (44%) patients had pathological positivity for cancer cell invasion into the nerve plexus of artery at the site of radiographic artery involvement, although one (11%) was diagnosed with pathological artery involvement.

CONCLUSION

PD-CHAR following neoadjuvant therapy might be feasible for PNBC without severe postoperative complications. Survival benefits in PNBC should be confirmed in further studies.

Circulating Tumor DNA as a Potential Prognostic Marker in Patients with Borderline-Resectable Pancreatic Cancer Undergoing Neoadjuvant Chemotherapy Followed by Pancreatectomy

BACKGROUND

Circulating tumor DNA (ctDNA) might be a promising biomarker for pancreatic cancer in liquid biopsy. This study aimed to evaluate the usefulness of liquid biopsy for patients with borderline-resectable pancreatic cancer (BR-PC).

METHODS

Patients with BR-PC according to the National Comprehensive Cancer Network guidelines (2017) and eligible for neoadjuvant chemotherapy (NAC) followed by pancreatectomy were recruited at Wakayama Medical University Hospital (UMIN000026647) between March 2017 and April 2020. The study enrolled 55 patients with locally advanced PC, and each patient consented to inclusion in the study. The study investigated the relationship between KRAS status in ctDNA and clinicopathologic features, analyzing ctDNA at three time points: pretreatment, post-NAC, and post-operation.

RESULTS

Of the 55 enrolled patients with a diagnosis of BR-PC, 34 were scheduled to undergo pancreatectomy. From 27 patients with resected BR-PC, 81 blood samples were analyzed in triplicate for ctDNA. The patients with positive pretreatment and post-NAC ctDNA status had no significant decrease in median relapse-free survival (RFS) or overall survival (OS). However, the patients with positive postoperation ctDNA status had a significantly shorter median OS (723 days) than the patients with negative ctDNA results (not reached; P = 0.0148). A combined analysis of postoperative ctDNA and CA19-9 values showed the cumulative effect on both RFS (P = 0.0066) and OS (P = 0.0046). The adjusted hazard ratio for risk of survival computed for the patients carrying risk factors (either detectable ctDNA or CA19-9 > 37 U/ml) increased from 4.13-fold to 17.71-fold (both P = 0.0055) compared with the patients who had no risk factors.

CONCLUSION

Positive ctDNA predicts poor survival for patients with BR-PC who undergo NAC followed by pancreatectomy.

Covered self-expandable metal stents versus plastic stents for preoperative biliary drainage in patient receiving neo-adjuvant chemotherapy for borderline resectable pancreatic cancer: Prospective randomized study

OBJECTIVES

This single-center comparative randomized superiority study compared biliary stenting using fully covered self-expandable metal stents (FCSEMS) and biliary stenting using plastic stents (PS) in preoperative biliary drainage of patients with borderline resectable pancreatic cancer (BRPC) who are planned to undergo a single regimen of neo-adjuvant chemotherapy (NAC).

METHODS

Twenty-two patients with BRPC who required preoperative biliary drainage before NAC (Gemcitabine plus Nab-paclitaxel) were randomly assigned 1:1 to the FCSEMS or PS group. The primary endpoint was the rate of stent dysfunction until surgery or tumor progression. Secondary endpoints were stent patency, number of re-interventions, adverse events of endoscopic retrograde biliary drainage (EBD), operation time, volume of intraoperative bleeding, postoperative hospitalization, postoperative adverse events and medical costs.

RESULTS

Eleven patients in each of the groups reached the primary endpoint. The FCSEMS group showed a significantly lower rate of stent dysfunction (18.2% vs. 72.8%, P = 0.015), longer stent patency (P = 0.02), and lower number of re-interventions for stent dysfunction (0.27 ± 0.65 vs. 1.27 ± 1.1, P = 0.001) than the PS group. The adverse events of EBD, operation time, volume of intraoperative bleeding, postoperative hospitalization, postoperative adverse events and medical costs did not significantly differ between the two groups.

CONCLUSIONS

In patients with BRPC for preoperative biliary drainage, stent dysfunction occurred less frequently with FCSEMSs than with PSs. In addition, FCSEMS and PS provided similar preoperative management of BRPC in terms of the safety of surgery and medical costs. (UMIN ID000030473).

ISOlation Procedure vs. conventional procedure during Distal Pancreatectomy (ISOP-DP trial): study protocol for a randomized controlled trial

BACKGROUND

Radical antegrade modular pancreatosplenectomy (RAMPS) is an isolation procedure in pancreatosplenectomy for pancreatic body/tail cancer. Connective tissues around the bifurcation of the celiac axis are dissected, followed by median-to-left retroperitoneal dissection. This procedure has the potential to isolate blood and lymphatic flow to the area of the pancreatic body/tail and the spleen to be excised. This is achieved by division of the inflow artery, transection of the pancreas, and then division of the outflow vein in the early phases of surgery. In cases of pancreatic ductal adenocarcinoma (PDAC), the procedure has been shown to decrease intraoperative blood loss and increase R0 resection rate by complete clearance of the lymph nodes. This trial investigates whether the isolation procedure can prolong the survival of patients with pancreatic ductal adenocarcinoma who undergo distal pancreatosplenectomy (DPS) compared with those that undergo the conventional approach.

METHODS/DESIGN

Patients with PDAC scheduled to undergo DPS are randomized before surgery to undergo either a conventional procedure (arm A) or to undergo the isolation procedure (arm B). In arm A, the pancreatic body, tail, and spleen are mobilized, followed by removal of the regional lymph nodes. The splenic vein is transected at the end of the procedure. The timing of division of the splenic artery (SA) is not restricted. In arm B, regional lymph nodes are dissected, then we transect the root of the SA, the pancreas, then the splenic vein. At the end of the procedure, the pancreatic body/tail and spleen are mobilized and removed. In total, 100 patients from multiple Japanese high-volume centers will be randomized. The primary endpoint is 2-year recurrence-free survival by intention-to-treat analysis. Secondary endpoints include intraoperative blood loss, R0 resection rate, and overall survival.

DISCUSSION

If this trial shows that the isolation procedures can improve survival with a similar R0 rate and with a similar number of lymph node dissections to the conventional procedure, the isolation procedure is expected to become a standard procedure during DPS for PDAC. Conversely, if there were no significant differences in endpoints between the groups, it would demonstrate justification of either procedure from surgical and oncological points of view.

TRIAL REGISTRATION

UMIN Clinical Trials Registry UMIN000041381 . Registered on 10 August 2020. ClinicalTrials.gov NCT04600063 . Registered on 22 October 2020.

Preoperative In-Hospital Rehabilitation Improves Physical Function in Patients with Pancreatic Cancer Scheduled for Surgery

Low preoperative physical function in cancer patients is associated with postoperative complications; however, there have been no reports on the benefits of in-hospital preoperative rehabilitation on preoperative physical function in patients with pancreatic cancer. Therefore, the aim of this study was to quantitatively determine the effects of preoperative in-hospital rehabilitation provided under the supervision of a physiotherapist, on preoperative physical function in patients with pancreatic cancer. The study subjects were 26 patients (15 males, 11 females; age 71.2 ± 8.5 years, range: 51-87 years), including four patients with preoperative chemotherapy, scheduled for surgery for pancreatic cancer. Muscle strengthening exercises and aerobic exercises were conducted 11.9 ± 5.1 days prior to surgery. Cardiopulmonary exercise testing, 6-minute walk distance, and the Functional Independence Measure score were measured before and after the rehabilitation program. We also investigated the relation between the rehabilitation program and incidence of postoperative complications. All 26 study patients completed the preoperative rehabilitation program and no adverse events were noted. Peak oxygen uptake during cardiopulmonary exercise testing and 6-minute walk distance increased significantly after the rehabilitation program. The Functional Independence Measure score remained constant throughout the intervention. No wound infection, delirium, deep vein thrombosis, or respiratory complications were encountered postoperatively. In-hospital preoperative rehabilitation under the supervision of a physiotherapist significantly improved physical function and maintained physical activity in patients with pancreatic cancer. Such improvements may contribute toward preventing serious postoperative complications, resulting in better outcomes.

Complete circumferential lymphadenectomy around the superior mesenteric artery with preservation of nerve plexus reduces locoregional recurrence after pancreatoduodenectomy for resectable pancreatic ductal adenocarcinoma

BACKGROUND

Evaluation of recurrence pattern and risk factors for recurrence are essential for good rates of survival after upfront pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).

METHODS

This retrospective study included 167 consecutive patients who underwent upfront PD for resectable PDAC between 2000 and 2018. Postoperative recurrences were classified into three patterns according to initial recurrence site: isolated locoregional, isolated distant, and simultaneous locoregional and distant recurrences.

RESULTS

This study found 114 patients who developed postoperative recurrence (68.3%), including 37 patients with isolated locoregional recurrence (32.5%), 67 patients with isolated distant recurrence (58.8%), and 10 patients with simultaneous locoregional and distant recurrences (6.0%). When locoregional recurrence was classified based on the location of recurrent lesions, locoregional recurrence most commonly occurred around the superior mesenteric artery (SMA) (70.2%), followed by around the hepatic artery (25.5%) and in the paraaortic region (14.9%). Multivariate analyses showed that complete circumferential lymphadenectomy around the SMA, including not only the right side, but also the left side, was an independent factor for reduction of locoregional recurrence (P = 0.019, odds ratio [OR]: 2.217). Lymph node metastasis was an independent risk factor for both locoregional (P < 0.001, OR: 3.686) and distant recurrences (P < 0.001, OR: 4.315). Non-completion of postoperative adjuvant therapy was a risk factor for distant recurrence (P < 0.001, OR: 3.748).

CONCLUSION

Based on our data, complete circumferential lymphadenectomy around the SMA might contribute to local control, and multidisciplinary treatment including neoadjuvant therapy might be needed for resectable PDAC with high risk for recurrence.

Previous upper abdominal surgery is a risk factor for nasogastric tube reinsertion after pancreaticoduodenectomy

BACKGROUND

Pancreaticoduodenectomy without subsequent nasogastric tube management has not been widely adopted due to delayed gastric emptying, the specific and frequent morbidity associated with this surgical procedure. We assessed the feasibility of pancreaticoduodenectomy without use of nasogastric tubes and the risk factors for subsequent nasogastric tube reinsertion.

METHODS

We retrospectively reviewed 465 patients who underwent pancreaticoduodenectomy at a single institution between 2010 and 2019. Primary endpoint was the rate of nasogastric tube reinsertion. Logistic regression analysis was used to determine independent risk factors of nasogastric tube reinsertion and delayed gastric emptying.

RESULTS

The rate of nasogastric tube reinsertion was 10.1% (47/465). The rate of delayed gastric emptying was 9.5% (44/465). Logistic regression analysis identified 4 independent risk factors for nasogastric tube reinsertion: male sex (odds ratio = 4.42; 95% confidence interval 1.50-13.0, P = .007), comorbidity of cardiac ischemia (odds ratio = 3.04; 95% confidence interval 1.05-8.79, P = .041), preoperative cholangitis or cholecystitis (odds ratio = 2.21; 95% confidence interval 1.02-4.76, P = .044), and previous upper abdominal surgery (odds ratio = 8.34; 95% confidence interval 3.07-22.7, P < .001). Independent risk factors for delayed gastric emptying were male sex (odds ratio = 3.20; 95% confidence interval 1.11-9.21, P = .031), comorbidity of cardiac ischemia (odds ratio = 3.81; 95% confidence interval 1.34-10.8, P = .012), concomitant organ resection (odds ratio = 3.99; 95% confidence interval 1.10-14.4, P = .035), and previous upper abdominal surgery (odds ratio = 7.21; 95% confidence interval 2.68-19.4, P < .001).

CONCLUSION

Pancreaticoduodenectomy without use of nasogastric tubes is feasible, but patients with previous upper abdominal surgery require careful postoperative nasogastric tube management.

Advances in immunotherapy for pancreatic ductal adenocarcinoma

Advances in immunotherapy against advanced cancers can be considered stunning and epoch-making. Meanwhile, efficacy of immune-based therapies, especially immune checkpoint inhibitors, remains insufficient in pancreatic ductal adenocarcinoma, differing from other immunogenic cancers. To date, neither immunotherapies targeting immune system acceleration nor release of immunologic brakes have been able to overcome the robust immune barrier in the pancreatic tumor microenvironment, which is characterized by rich fibrotic stroma and accumulation of immunosuppressive myeloid cells. However, by receiving an immune checkpoint blockade, patients with abundant tumor-infiltrating lymphocytes in pancreatic ductal adenocarcinoma clearly have better prognosis, and patients with mismatch repair deficiency have achieved better outcomes, albeit in a small population of pancreatic ductal adenocarcinoma. We overview recent preclinical and clinical studies that have been concerned with immune-based therapies including cancer vaccine and immune checkpoint inhibitors. By providing a deep insight into the immunosuppressive tumor microenvironment, we suggest the possibility of comprehensive immune intensification that could reverse the tumor microenvironment, making it conducive to cytotoxic T lymphocyte activity for overcoming pancreatic ductal adenocarcinoma.

Concomitant improvement in anti-saccade success rate and postural instability gait difficulty after rTMS treatment for Parkinson's disease

Parkinson’s disease (PD) is a progressive neurological disorder characterised by motor and non-motor deficits. Repetitive transcranial magnetic stimulation (rTMS) over the bilateral primary motor cortex at a high frequency (5 Hz or higher) is reported to be a potential treatment of PD. We aimed to assess the effect of rTMS on eye movement control in patients with PD in their ‘on’ state. We enrolled 14 patients with PD and assessed motor symptoms (Movement Disorder Society-Sponsored Unified Parkinson’s Disease Rating Scale; MDS-UPDRS) and eye movement performances (visually guided saccades, volitional anti-saccades, and small involuntary saccades during fixation) at baseline and after administering bilateral 10 Hz rTMS on leg region of the motor cortex. We confirmed that rTMS improved the MDS-UPDRS motor scores and found that rTMS improved the anti-saccade success rate, which requires adequate inhibition of the reflexive response. The improvement in anti-saccade success rate was correlated with that of the postural instability gait difficulty (PIGD) sub-scores of MDS-UPDRS and lower baseline Japanese version of the Montreal Cognitive Assessment scores. This result is consistent with previous findings that PIGD and inhibitory control deficits share common brain dysfunctions in PD. rTMS may alleviate dysfunctions of that circuit and have a clinical effect.

Limited resection vs. pancreaticoduodenectomy for primary duodenal adenocarcinoma: a systematic review and meta-analysis

It is well known that surgery is the mainstay treatment for duodenal adenocarcinoma. However, the optimal extent of surgery is still under debate. We aimed to systematically review and perform a meta-analysis of limited resection (LR) and pancreatoduodenectomy for patients with duodenal adenocarcinoma. A systematic electronic database search of the literature was performed using PubMed and the Cochrane Library. All studies comparing LR and pancreatoduodenectomy for patients with duodenal adenocarcinoma were selected. Long-term overall survival was considered as the primary outcome, and perioperative morbidity and mortality as the secondary outcomes. Fifteen studies with a total of 3166 patients were analyzed; 995 and 1498 patients were treated with limited resection and pancreatoduodenectomy, respectively. Eight and 7 studies scored a low and intermediate risk of publication bias, respectively. The LR group had a more favorable result than the pancreatoduodenectomy group in overall morbidity (odd ratio [OR]: 0.33, 95% confidence interval [CI] 0.17-0.65) and postoperative pancreatic fistula (OR: 0.13, 95% CI 0.04-0.43). Mortality (OR: 0.96, 95% CI 0.70-1.33) and overall survival (OR: 0.61, 95% CI 0.33-1.13) were not significantly different between the two groups, although comparison of the two groups stratified by prognostic factors, such as T categories, was not possible due to a lack of detailed data. LR showed long-term outcomes equivalent to those of pancreatoduodenectomy, while the perioperative morbidity rates were lower. LR could be an option for selected duodenal adenocarcinoma patients with appropriate location or depth of invasion, although further studies are required.

Prognostic impact of adjuvant chemolipiodolization and treatment frequency on patients with hepatocellular carcinoma after hepatectomy: Prospective study with historical control group

BACKGROUND

Reducing or minimizing metastatic recurrence is a consideration in prolongation of survival of patients with hepatocellular carcinoma. We previously proposed single adjuvant chemolipiodolization (ACL) as a possible adjuvant treatment. The current study aims to further improve prognosis by performing ACL three times (sequential-ACL).

METHODS

We examined the prognostic impact of sequential-ACL compared with our historical cohort groups: resection alone (non-ALC) and single-ACL. We evaluated recurrence-free survival (RFS), recurrence pattern, and overall survival. Multivariate prognostic analyses were used to adjust baseline bias between three treatment groups.

RESULTS

Non-ACL (n = 64), single-ACL (n = 137), and sequential-ACL (n = 95) showed 40, 54, and 62% of two-year RFS rates (P = 0.03 and P = 0.007 compared with non-ACL). Recurrence pattern beyond Milan criteria was frequently observed in the non-ACL group (P = 0.003). Five-year overall survival rates of these three groups were 53, 69, and 77% (P = 0.02 and 0.002 compared with non-ACL). Single- and sequential-ACL were selected as independent favorable factors for five-year overall survival; their hazard ratios (95% confidence interval) were 0.61 (0.37-0.99) and 0.48 (0.26-0.86). However, compared with single-ACL, there was no additional prognostic effects of sequential-ACL.

CONCLUSIONS

Single- and sequential-ACL treatment both showed better RFS and overall survival with minimized recurrence patterns than resection alone. There was not sufficient additional benefit by sequential-ACL, however, over single-ACL. Single-ACL might therefore be appropriate as an adjuvant therapy.

Endoscopic ultrasound-guided fine needle aspiration with contrast-enhanced harmonic imaging for diagnosis of gallbladder tumor (with video)

Highlight Endoscopic ultrasound-guided fine needle aspiration with contrast-enhanced harmonic imaging is useful for accurately and safely obtaining tissue from a gallbladder tumor. Tamura and colleagues demonstrate how contrast-enhanced harmonic endoscopic ultrasound facilitates puncturing the gallbladder tumor while avoiding fluid spaces as it demarcates the borderline between the tumor and fluid spaces.

No Significant Effect of Daikenchuto (TJ-100) on Peritoneal IL-9 and IFN-γ Levels After Pancreaticoduodenectomy

Aim and Background

TJ-100 is a traditional Japanese medicine that affects inflammation and gastrointestinal motility, and is used as a preventive and treatment for paralytic ileus. This study aims at determining the effect of TJ-100 on the peritoneal levels of IFN-γ/IL-9, cytokines related to ileus, after pancreaticoduodenectomy (PD) in a clinical setting.

Methods

This was a subsidiary study of the clinical trial investigating the effect of TJ-100 on postoperative bowel function. Ascites was collected from 180 patients using an abdominal drainage tube on postoperative day 1 and 3 after PD (POD 1 or POD 3) and used to measure 27 cytokines. We performed univariate and multivariate analyses using several perioperative variables and administration of TJ-100/placebo to determine the effect of TJ-100 on the levels of IFN-γ and IL-9.

Results

Peritoneal levels of IL-9 and IFN-γ decreased between POD 1 and 3 (Wilcoxon signed-rank test p<0.001). Multivariate analysis was performed after univariate analysis to select the variables and patients with a body mass index of ≥22 kg/m², older age, use of epidural anesthesia, and longer surgery correlated with the levels of IL-9 and IFN-γ. However, we could not detect a correlation between the use of TJ-100 and cytokine levels in ascites either on POD 1 or 3.

Conclusion

TJ-100 did not affect peritoneal IL-9 and IFN-γ levels after PD. This was in accordance with published clinical findings showing no improvement in bowel function after PD and TJ-100 treatment.

Prefrontal Responses to Odors in Individuals With Autism Spectrum Disorders: Functional NIRS Measurement Combined With a Fragrance Pulse Ejection System

Individuals with autism spectrum disorders (ASD) are impaired not only in social competencies but also in sensory perception, particularly olfaction. The olfactory ability of individuals with ASD has been examined in several psychophysical studies, but the results have been highly variable, which might be primarily due to methodological difficulties in the control of odor stimuli (e.g., the problem of lingering scents). In addition, the neural correlates of olfactory specificities in individuals with ASD remain largely unknown. To date, only one study has investigated this issue using functional magnetic resonance imaging (fMRI). The present study utilized a sophisticated method-a pulse ejection system-to present well-controlled odor stimuli to participants with ASD using an ASD-friendly application. With this advantageous system, we examined their odor detection, identification, and evaluation abilities and measured their brain activity evoked by odors using functional near-infrared spectroscopy (fNIRS). As the odor detection threshold (DT) of participants with ASD was highly variable, these participants were divided into two groups according to their DT: an ASD-Low DT group and an ASD-High DT group. Behavioral results showed that the ASD-High DT group had a significantly higher DT than the typically developing (control) group and the ASD-Low DT group, indicating their insensitivity to the tested odors. In addition, while there was no significant difference in the odor identification ability between groups, there was some discrepancy between the groups' evaluations of odor pleasantness. The brain data identified, for the first time, that neural activity in the right dorsolateral prefrontal cortex (DLPFC) was significantly weaker in the ASD-High DT group than in the control group. Moreover, the strength of activity in the right DLPFC was negatively correlated with the DT. These findings suggest that participants with ASD have impairments in the higher-order function of olfactory processing, such as olfactory working memory and/or attention.

Impact of Ninjin'Yoeito on Fatigue in Patients Receiving Nab-Paclitaxel Plus Gemcitabine Therapy: A Prospective, Single-Arm, Phase II Open Label, Nonrandomized, Historically-Controlled Study

Background

Ninjin'yoeito, a traditional Japanese herbal medicine, is used to prevent fatigue, loss of appetite, and coldness of limbs. Fatigue is an especially common issue during chemotherapy and can affect quality of life and the ability to complete scheduled treatment.

Objectives

This prospective exploratory trial evaluates the efficacy of ninjin'yoeito for fatigue in patients undergoing nab-paclitaxel plus gemcitabine therapy for unresectable pancreatic cancer. The primary end point was evaluation of fatigue according to Functional Assessment of Chronic Illness Therapy-Fatigue score during 2 courses of nab-paclitaxel plus gemcitabine therapy. Secondary end points included evaluation of dose intensity, appetite loss using numerical rating scale, and peripheral neuropathy using a patient neurotoxicity questionnaire.

Methods

We compared data from this interventional trial with a prior observational trial without administration of ninjin'yoeito with identical definition of end points (UMIN000021758). Thirty patients were required by the study.

Results

Threshold mean of Functional Assessment of Chronic Illness Therapy-Fatigue score across 8 weeks during chemotherapy was under 5.3 (P = 0.002). Secondary end points did not reveal any specific patterns in appetite loss or degree of pain. No significant changes in patient neurotoxicity questionnaire concerning sensory/motor disorders were observed, but the mean (SD) incidence of patients with sensory disturbance was higher between the fifth and eighth weeks (8.8 [1.26]) than during the first and fourth weeks (4.8 [0.96]) (P = 0.003). Clinically significant adverse reactions of ninjin'yoeito were not observed.

Conclusions

Ninjin'yoeito may be useful for improving the symptoms of fatigue caused by nab-paclitaxel plus gemcitabine in patients with unresectable pancreatic cancer. UMIN Clinical Trials Registry identifier: UMIN000025606. (Curr Ther Res Clin Exp. 2020; 81:XXX–XXX)

Surgical indication for intraductal papillary mucinous neoplasm without mural nodule ≥5 mm

BACKGROUND

In intraductal papillary mucinous neoplasm, a mural nodule ≥5 mm is an important predictor of malignancy. Surgical indication is less clear in cases of intraductal papillary mucinous neoplasm without mural nodule ≥5 mm. This is a retrospective study evaluating predictors of high-grade dysplasia or invasive intraductal papillary mucinous carcinoma for intraductal papillary mucinous neoplasm without mural nodule ≥5 mm.

METHODS

Among consecutive patients who underwent surgery for intraductal papillary mucinous neoplasm between 1999 and 2018, 174 had intraductal papillary mucinous neoplasm with mural nodule ≥5 mm (mural nodule[+] ≥5 mm group). The remaining 155 patients had intraductal papillary mucinous neoplasm but did not have mural nodule ≥5 mm: 24 patients with mural nodule <5 mm (mural nodule[+] <5 mm group) and 131 patients without mural nodule (mural nodule[-] group). We investigated predictors of high-grade dysplasia or invasive intraductal papillary mucinous neoplasm in cases of intraductal papillary mucinous neoplasm without mural nodule ≥5 mm.

RESULTS

The frequency of high-grade dysplasia invasive intraductal papillary mucinous neoplasm was significantly higher in the mural nodule(+) ≥5 mm group (87.4%) than in the mural nodule(+) <5 mm group (37.5%, P < .001) and mural nodule(-) group (45.0%, P < .001). However, frequency was not significantly different between mural nodule(+) <5 mm and mural nodule(-) groups (P = .494). Multivariate analysis showed three independent predictors of high-grade dysplasia invasive intraductal papillary mucinous carcinoma in intraductal papillary mucinous neoplasm without mural nodule ≥5 mm: branch cyst ≥40 mm (P = .038, odds ratio 3.704; 95% confidence interval, 1.075-12.821), positive cytology of pancreatic juice (P = .039, odds ratio 16.792; 95% confidence interval, 1.152-244.744), and carcinoembryonic antigen in pancreatic juice ≥30 mg/mL (P < .001, odds ratio 14.925; 95% confidence interval, 4.525-50.0).

CONCLUSION

For cases of intraductal papillary mucinous neoplasm without mural nodule ≥5 mm, large cysts, positive cytology of the pancreatic juice, and high levels of carcinoembryonic antigen in pancreatic juice may be useful to determine surgical indication, although further studies are needed to confirm these results.

Radiographic Splenic Artery Involvement Is a Poor Prognostic Factor in Upfront Surgery for Patients with Resectable Pancreatic Body and Tail Cancer

PURPOSE

The prognostic impact of radiographic splenic vessel involvement in pancreatic cancer remains unclear. We evaluate its oncological significance in resectable pancreatic body/tail cancer.

PATIENTS AND METHODS

We retrospectively review 102 cases of resectable pancreatic cancer and 51 of borderline resectable pancreatic cancer (BRPC) who underwent pancreatectomy for pancreatic body/tail cancer. Resectable pancreatic body/tail cancer was classified into one of three categories based on radiographic splenic vessel involvement.

RESULTS

Among 102 cases of resectable pancreatic cancer, 37 (36.3%), 35 (34.3%), and 30 cases (29.4%) were classified as no splenic vessel involvement (R_none), splenic vein involvement (RV), and splenic artery involvement (RA), respectively. Disease-free survival (DFS) among patients with R_none, RV, RA, and BRPC was 58.5, 18.4, 10.8, and 9.2 months, respectively. Patients with RV and RA had significantly poorer DFS than patients with R_none (P = 0.010, P < 0.001, respectively). Median survival among R_none, RV, RA, and BRPC was 80.6, 23.4, 15.1, and 21.3 months, respectively. Patients with RV and RA had significantly poorer survival than patients with R_none (P = 0.001, P < 0.001, respectively) and had short survival similar to that of those with BRPC. Multivariate Cox proportional hazard analysis detected preoperative CA19-9 ≥ 37 IU/L, radiologic splenic vein involvement, radiologic splenic artery involvement, intraoperative bleeding ≥ 500 ml, transfusion, positive washing cytology, and noncompletion of adjuvant therapy as independent prognostic factors.

CONCLUSIONS

Radiographic splenic artery involvement is a poor prognostic factor in resectable pancreatic body/tail cancer and may have a role in stratification of treatment strategy.

Effective Response of Intrahepatic Cholangiocarcinoma to Pembrolizumab: A Case Report

BACKGROUND/AIM

The efficacy of pembrolizumab for intrahepatic cholangiocellular carcinoma (IHCCC) is not widely reported.

CASE REPORT

We began pembrolizumab treatment in a 69-year-old male with recurrent IHCCC at 18 months after his surgery because of the proven microsatellite instability (MSI)-high status. The patient had partial response, with an 82.5% reduction at the end of 18 courses. Immunostaining of the primary tumor revealed intra-tumoral infiltration of both PD-1+ and CD8+ T cells, and a low expression of PD-L1.

CONCLUSION

Intra-tumoral infiltration of both PD-1+ and CD8+ T cells may be a predictive factor of the efficacy of pembrolizumab. Expression of PD-L1 did not correlate with a therapeutic effect, but the tumor microenvironment of our patient's recurrent lesions may have been modified by conventional chemotherapy and CD8+ T cells.

Preoperative Scoring System to Predict Prognosis in Patients Who Undergo Neoadjuvant Therapy for Pancreatic Cancer

BACKGROUND/AIM

This study investigated the feasibility of an integrated scoring system of preoperative prognostic parameters using data from before/after neoadjuvant therapy in patients with borderline resectable pancreatic cancer (BRPC).

PATIENTS AND METHODS

We constructed and analyzed a prognostic scoring system using factors that were previously reported to be significant prognostic indicators or predictors of histological response.

RESULTS

We analyzed 28 consecutive patients with BRPC who underwent neoadjuvant therapy and subsequent surgical resection. Overall survival (OS) and recurrence free survival (RFS) were greater in patients with high scores (n=11) than in patients with low scores (n=17; log-rank test p=0.03/0.028). Pathological N0 status (p<0.05) and tumor cell destruction rate >50% (p<0.05) were found at a higher incidence among patients with high scores.

CONCLUSION

OS and RFS can be predicted with an integrated scoring system that uses prognostic indices before/after neoadjuvant therapy for BRPC.

The development of therapeutic cancer vaccine for pancreatic cancer

707

Background: A previous phase II/III trial using a single cancer peptide vaccine derived from vascular endothelial growth factor receptor (VEGFR)2 for patients with advanced pancreatic cancer did not demonstrate the overall survival (OS) benefit (Yamaue et al. Cancer Sci 2015). However, for the next trial, we conducted a multicenter phase II study using multipeptide cocktail vaccine named OCV-C01 derived from a novel higher immunogenic antigen KIF20A, VEGFR1 and VEGFR2 combined with gemcitabine in postoperative adjuvant setting. Methods: A single-arm multicenter phase II study was performed on 30 patients with pancreatic ductal carcinoma who underwent pancreatectomy. At each 28-day treatment cycle, patients received weekly subcutaneous injection of OCV-C01 for 48 weeks, and gemcitabine was administered intravenously at 1,000 mg/m2 on days 1, 8, and 15 for 24 weeks. Patients were followed for 18 months. The primary endpoint was disease-free survival (DFS) and secondary endpoints included safety, OS and immunological assays on peptide-specific cytotoxic T lymphocyte (CTL) activity and KIF20A expression in resected pancreatic cancer. Results: The median DFS was 15.8 months (95% confidence interval (CI), 11.1-20.6), and the DFS rate at 18 months was 34.6% (95% CI, 18.3-51.6). The median OS was not reached and the OS rate at 18 months was 69.0% (95% CI, 48.8-82.5). The administration of OCV-C01 was well tolerated. In the per protocol set, there were significant differences in DFS between patients with and without KIF20A-specific CTL responses (p = 0.027), and between patients with and without KIF20A expression in resected pancreatic cancer tissues (p = 0.014). In addition, all four patients who underwent R0 resection with KIF20A expression had no recurrence of pancreatic cancer with KIF20A-specific CTL responses. Conclusions: OCV-C01 combined with gemcitabine was tolerable with a favorable median DFS of 15.8 months. In cancer vaccine treatment, positive expression of targeted antigen was essential, and postoperative adjuvant setting was more suitable than advanced state of cancer. Clinical trial information: UMIN000007991.

Diffusion-weighted MRI predicts the histologic response for neoadjuvant therapy in patients with pancreatic cancer: a prospective study (DIFFERENT trial)

PURPOSE

Pre-operative prediction of histological response to neoadjuvant therapy aids decisions regarding surgical management of borderline resectable pancreatic cancer (BRPC). We elucidate correlation between pre-/post-treatment whole-tumor apparent diffusion coefficient (ADC) value and rate of tumor cell destruction. We newly verify whether post-treatment ADC value at the site of vascular contact predicts R0 resectability of BRPC.

METHODS

We prospectively reviewed 28 patients with BRPC who underwent diffusion-weighted magnetic resonance imaging before neoadjuvant chemotherapy and surgery. Correlation between the percentage of tumor cell destruction and various parameters was analyzed. Strong parameters were assessed for their ability to predict therapeutic histological response and R0 resectability.

RESULTS

Pre-/post-treatment whole-tumor ADC value correlated with tumor cell destruction rate by all parameters (R = 0.630/0.714, P < 0.001/< 0.0001). The post-treatment cutoff value of ADC at the site of vascular contact for discriminating histological response of tumor destruction of ≤ 50% and tumor destruction of > 50% was determined at 1.42 × 10^-3 mm²/s. It predicts R0 with 88% sensitivity, 50% specificity, and 61% accuracy. For histological response, the post-treatment whole-tumor ADC cutoff value for discriminating between tumor destruction of ≤ 50% and tumor destruction of > 50% was determined at 1.40 × 10^-3 mm²/s. It predicts histological response with 100% sensitivity, 81% specificity, and 89% accuracy. It predicts R0 with 88% sensitivity, 70% specificity, and 75% accuracy.

CONCLUSIONS

Post-treatment whole-tumor ADC value may be a predictor of R0 resectability in patients with BRPC. Tumor cell destruction rate is indicated by the difference between pre-/post-treatment ADC values. This difference is strongly affected by the pre-treatment ADC value. The cutoff value of ADC at the site of vascular contact could not discriminate R0 resectability.

Prognostic Analysis of Hepatocellular Carcinoma With Hepatitis C Virus Infection Using Epithelial-Mesenchymal Transition Gene Profiles

BACKGROUND

Epithelial-mesenchymal transition genes have prognostic influence on hepatocellular carcinoma (HCC). Previously, the following four epithelial-mesenchymal transition-related genes were considered to be significantly influential: E-cadherin (CDH1), inhibitor of DNA binding 2 (ID2), matrix metalloproteinase 9 (MMP9), and transcription factor 3 (TCF3). A prognostic prediction model, NRISK4 = (-0.333 × [CDH1] - 0.400 × [ID2] + 0.339 × [MMP9] + 0.387 × [TCF3]) was constructed, but from patients with HCC with predominantly hepatitis B virus infection. We therefore aim to validate if this model also fits patients with HCC and hepatitis C virus (HCV) infection.

METHODS

We collected HCC tissue samples from 67 patients with HCV infection. Discrimination of the NRISK4 was re-estimated using receiver operating curve analysis and we redefined the appropriate cutoff value. Using this cutoff value, patients were divided into two groups (high/low risk patients) and we compared their clinicopathological factors and prognosis.

RESULTS

Area under the curve of NRISK4 prediction was 0.70 and an appropriate cutoff value was 3.19 in this cohort. Patients were divided into high- (n = 25) and low-risk (n = 42) patients for prognosis. There were no significant differences in tumor factors between the two groups. Cancer-specific survival rates at 5 y after surgery on high- and low-risk patients were 45% and 68%, respectively (P = 0.02). At 2 y after surgery, recurrence rates were 68% and 37% among high- and low-risk patients, respectively (P = 0.01). Aggressive recurrences were highly observed in the high-risk patients (P = 0.01).

CONCLUSIONS

NRISK4 model could also successfully validate prognosis of patients with HCC with HCV infection similarly to in the previous report of patients with hepatitis B virus infection, especially in the early period after surgery.

Neoadjuvant FOLFIRINOX in Patients With Borderline Resectable Pancreatic Cancer: A Systematic Review and Patient-Level Meta-Analysis

BACKGROUND

FOLFIRINOX is a standard treatment for metastatic pancreatic cancer patients. The effectiveness of neoadjuvant FOLFIRINOX in patients with borderline resectable pancreatic cancer (BRPC) remains debated.

METHODS

We performed a systematic review and patient-level meta-analysis on neoadjuvant FOLFIRINOX in patients with BRPC. Studies with BRPC patients who received FOLFIRINOX as first-line neoadjuvant treatment were included. The primary endpoint was overall survival (OS), and secondary endpoints were progression-free survival, resection rate, R0 resection rate, and grade III-IV adverse events. Patient-level survival outcomes were obtained from authors of the included studies and analyzed using the Kaplan-Meier method.

RESULTS

We included 24 studies (8 prospective, 16 retrospective), comprising 313 (38.1%) BRPC patients treated with FOLFIRINOX. Most studies (n = 20) presented intention-to-treat results. The median number of administered neoadjuvant FOLFIRINOX cycles ranged from 4 to 9. The resection rate was 67.8% (95% confidence interval [CI] = 60.1% to 74.6%), and the R0-resection rate was 83.9% (95% CI = 76.8% to 89.1%). The median OS varied from 11.0 to 34.2 months across studies. Patient-level survival data were obtained for 20 studies representing 283 BRPC patients. The patient-level median OS was 22.2 months (95% CI = 18.8 to 25.6 months), and patient-level median progression-free survival was 18.0 months (95% CI = 14.5 to 21.5 months). Pooled event rates for grade III-IV adverse events were highest for neutropenia (17.5 per 100 patients, 95% CI = 10.3% to 28.3%), diarrhea (11.1 per 100 patients, 95% CI = 8.6 to 14.3), and fatigue (10.8 per 100 patients, 95% CI = 8.1 to 14.2). No deaths were attributed to FOLFIRINOX.

CONCLUSIONS

This patient-level meta-analysis of BRPC patients treated with neoadjuvant FOLFIRINOX showed a favorable median OS, resection rate, and R0-resection rate. These results need to be assessed in a randomized trial.

Diagnostic efficacy of smear plus liquid-based cytology for EUS-FNA of solid pancreatic lesions: A propensity-matched study

Liquid-based cytology (LBC) is a thin-layer slide preparation procedure that was developed to overcome the cell crowding and contamination associated with smear cytology (SC). The present study compared diagnostic efficacy between SC alone and SC combined with LBC (SLBC) using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) samples of pancreatic lesions.We retrospectively analyzed data derived from 311 consecutive patients. Specimens obtained via EUS-FNA from 179 patients between December 2011 and May 2016 were analyzed by SC, and those obtained from 132 patients between June 2016 and October 2017 were analyzed by SLBC. The 2 groups were compared in terms of adequate sample rate, diagnostic accuracy, sensitivity, and specificity using propensity score matching.SC and SLBC were compared using propensity score-matching in 204 patients (n = 102 per group). The adequate sample rate did not differ significantly between SLBC (100%) and SC (99.0%, P = 1). Diagnostic sensitivity, negative predictive value and accuracy were better for SLBC than for SC in terms of cytological (93.2% vs 67.4%, 68.4% vs 23.1%, and 94.1% vs 69.6%, P < .01 each, respectively) and cytohistological (95.5% vs 81.5%, 76.5% vs 34.6%, and 96.1% vs 82.4%, P < .01, P = .02, and P < .01, respectively) analyses.SLBC improves the diagnostic efficacy of EUS-FNA for pancreatic lesions compared to LBC.

Standardization of surgical procedures for laparoscopic Spiegel lobectomy: A single-institutional experience

INTRODUCTION

Surgical techniques for Spiegel lobectomy remain technically difficult because of its deep anatomical location. Laparoscopic Spiegel lobectomy has not yet been standardized or widely reported. In the current study, we introduce technical improvements, including the liver hanging maneuver, to laparoscopic Spiegel lobectomy. Additionally, we demonstrate the safety and feasibility of this procedure.

MATERIALS AND SURGICAL TECHNIQUE

We performed consecutive laparoscopic Spiegel lobectomy on six patients: five with hepatocellular carcinoma and one with colorectal liver metastasis. As preparation before liver parenchymal resection, necessary and sufficient mobilization of the Spiegel lobe was performed. A few Glissonian pedicles of the Spiegel lobe were exposed from the hilar plate and divided to reduce the inflow to the Spiegel lobe. After that, vessel tape was used in the hanging maneuver. The tape was pulled forward to give the cutting plane moderate tension during liver parenchymal resection. Lifting this tape provided better exposure for determining the correct cutting plane during liver parenchymal transection. The median operation time was 207 min (range, 147-240 min) and the median intraoperative blood loss was 35 mL (range, 15-85 mL). There were no severe postoperative complications.

DISCUSSION

We safely performed laparoscopic Spiegel lobectomy. To maintain a sufficient surgical view, especially during liver parenchymal resection, the hanging maneuver may be a useful technique. This single-center investigation into standardized laparoscopic Spiegel lobectomy featuring improvements in technique showed potential for favorable results.

Decreased serum carbohydrate antigen 19-9 levels after neoadjuvant therapy predict a better prognosis for patients with pancreatic adenocarcinoma: a multicenter case-control study of 240 patients

Background

Carbohydrate antigen (CA) 19–9 levels after resection are considered to predict prognosis; however, the significance of decreased CA19–9 levels after neoadjuvant therapy has not been clarified. This study aimed to define the prognostic significance of decreased CA19–9 levels after neoadjuvant therapy in patients with pancreatic adenocarcinoma.

Methods

Between 2001 and 2012, 240 consecutive patients received neoadjuvant therapy and subsequent resection at seven high-volume institutions in Japan. These patients were divided into three groups: Normal group (no elevation [≤37 U/ml] before and after neoadjuvant therapy), Responder group (elevated levels [> 37 U/ml] before neoadjuvant therapy but decreased levels [≤37 U/ml] afterwards), and Non-responder group (elevated levels [> 37 U/ml] after neoadjuvant therapy). Analyses of overall survival and recurrence patterns were performed. Uni- and multivariate analyses were performed to clarify the clinicopathological factors influencing overall survival. The initial metastasis sites were also evaluated in these groups.

Results

The Responder group received a better prognosis than the Non-responder group (3-year overall survival: 50.6 and 41.6%, respectively, P = 0.026), but the prognosis was comparable to the Normal group (3-year overall survival: 54.2%, P = 0.934). According to the analysis of the receiver operating characteristic curve, the CA19–9 cut-off level defined as no elevation after neoadjuvant therapy was ≤103 U/ml. The multivariate analysis revealed that a CA19–9 level ≤ 103 U/ml, (P = 0.010, hazard ratio: 1.711; 95% confidence interval: 1.133–2.639), tumor size ≤27 mm (P = 0.040, 1.517; (1.018–2.278)), a lack of lymph node metastasis (P = 0.002, 1.905; (1.276–2.875)), and R0 status (P = 0.045, 1.659; 1.012–2.627) were significant predictors of overall survival. Moreover, the Responder group showed a lower risk of hepatic recurrence (18%) compared to the Non-responder group (31%), though no significant difference in loco-regional, peritoneal or other distant recurrence were observed between groups (P = 0.058, P = 0.700 and P = 0.350, respectively).

Conclusions

Decreased CA19–9 levels after neoadjuvant therapy predicts a better prognosis, with low incidence of hepatic recurrence after surgery.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5460-4) contains supplementary material, which is available to authorized users.

Ocular drift reflects volitional action preparation

Human cognitive behavior is predictive rather than reflexive because of volitional action preparation. Recent studies have shown that the covert process of volitional action preparation can be decoded from overt fixational eye movements of fixational/microsaccades and pupil dilation. Ocular drift, the slowest fixational eye movements, is also under the active neural control, but its relationship with cognitive behavior is unknown. Here, we examined whether ocular drift also reflects volitional action preparation. We analyzed ocular drift while adult humans maintained fixation on a central visual stimulus as they prepared to generate a volitional saccade. We adopted the antisaccade paradigm in which subjects generate a targeting saccade toward the opposite direction of a peripheral visual stimulus. Our findings are the following five points. First, ocular drift was slower when subjects prepared for targeting saccade initiation than when such preparation was unnecessary. Second, ocular drift was slowed down with elapsed time from fixation initiation, which was associated with the facilitation of targeting saccade initiation. Third, ocular drift was further slowed on correct antisaccade trials than when subjects failed to suppress targeting saccades toward peripheral stimuli. Fourth, such correlation with antisaccade performance was observed immediately after fixation initiation in ocular drift, but it emerged more slowly in the other fixational eye movements. Fifth, subjects with unstable fixation because of faster ocular drift had poorer antisaccade performance. We suggest that fixation stability measured by ocular drift can be used to decode the covert process of volitional action preparation along with the other fixational eye movements.

Outcomes and Risk Score for Distal Pancreatectomy with Celiac Axis Resection (DP-CAR): An International Multicenter Analysis

Background

Distal pancreatectomy with celiac axis resection (DP-CAR) is a treatment option for selected patients with pancreatic cancer involving the celiac axis. A recent multicenter European study reported a 90-day mortality rate of 16%, highlighting the importance of patient selection. The authors constructed a risk score to predict 90-day mortality and assessed oncologic outcomes.

Methods

This multicenter retrospective cohort study investigated patients undergoing DP-CAR at 20 European centers from 12 countries (model design 2000–2016) and three very-high-volume international centers in the United States and Japan (model validation 2004–2017). The area under receiver operator curve (AUC) and calibration plots were used for validation of the 90-day mortality risk model. Secondary outcomes included resection margin status, adjuvant therapy, and survival.

Results

For 191 DP-CAR patients, the 90-day mortality rate was 5.5% (95 confidence interval [CI], 2.2–11%) at 5 high-volume (≥ 1 DP-CAR/year) and 18% (95 CI, 9–30%) at 18 low-volume DP-CAR centers (P = 0.015). A risk score with age, sex, body mass index (BMI), American Society of Anesthesiologists (ASA) score, multivisceral resection, open versus minimally invasive surgery, and low- versus high-volume center performed well in both the design and validation cohorts (AUC, 0.79 vs 0.74; P = 0.642). For 174 patients with pancreatic ductal adenocarcinoma, the R0 resection rate was 60%, neoadjuvant and adjuvant therapies were applied for respectively 69% and 67% of the patients, and the median overall survival period was 19 months (95 CI, 15–25 months).

Conclusions

When performed for selected patients at high-volume centers, DP-CAR is associated with acceptable 90-day mortality and overall survival. The authors propose a 90-day mortality risk score to improve patient selection and outcomes, with DP-CAR volume as the dominant predictor.

Electronic supplementary material

The online version of this article (10.1245/s10434-018-07101-0) contains supplementary material, which is available to authorized users.

MAPLE-PD trial (Mesenteric Approach vs. Conventional Approach for Pancreatic Cancer during Pancreaticoduodenectomy): study protocol for a multicenter randomized controlled trial of 354 patients with pancreatic ductal adenocarcinoma

Background

The mesenteric approach is an artery-first approach to pancreaticoduodenectomy for pancreatic cancer, which starts with the dissection of connective tissues around the superior mesenteric artery. The procedure aims for early confirmation of resectability by checking the surgical margin around the superior mesenteric artery first during the operation. It also aims to decrease intraoperative blood loss by early ligation of the inferior pancreaticoduodenal artery and to increase R0 rate by complete clearance of the lymph nodes around the superior mesenteric artery and pancreatic head plexus II, the most favorable positive margin site for pancreatic ductal adenocarcinoma. Furthermore, it aims to avoid the spread of cancer cells during operation (nontouch isolation technique). The MAPLE-PD (Mesenteric Approach vs. Conventional Approach for Pancreatic Cancer during Pancreaticoduodenectomy) trial investigates whether the mesenteric approach can prolong the survival of patients with pancreatic ductal adenocarcinoma who undergo pancreaticoduodenectomy compared with the conventional approach.

Methods/design

The MAPLE-PD trial is a Japanese multicenter randomized controlled trial that compares the surgical outcomes between the mesenteric and conventional approaches to pancreaticoduodenectomy. Patients with pancreatic ductal adenocarcinoma scheduled to undergo pancreaticoduodenectomy are randomized before operation to either a conventional approach (arm A) or a mesenteric approach (arm B). In arm A, the operation starts with Kocher’s maneuver. At the final step of the removal procedure, the connective tissues around the superior mesenteric artery are dissected. In arm B, the operation starts with dissection of the connective tissues around the superior mesenteric artery and ends with Kocher’s maneuver. In total, 354 patients from 15 Japanese high-volume centers will be randomized. The primary endpoint is overall survival by intention-to-treat analysis. Secondary endpoints include intraoperative blood loss, R0 rate, and recurrence-free survival.

Discussion

If the MAPLE-PD trial shows the oncological benefits of the mesenteric approach for patients with pancreatic ductal adenocarcinoma, this procedure may become a standard approach to pancreaticoduodenectomy.

Trial registration

ClinicalTrials.gov, NCT03317886. Registered on 23 October 2017.

University Hospital Medical Information Network Clinical Trials Registry, UMIN000029615. Registered on 15 January 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3002-z) contains supplementary material, which is available to authorized users.

Transition of serum cytokines following pancreaticoduodenectomy: A subsidiary study of JAPAN-PD

Our previous study aimed to examine the effect of TJ-100, a widely used herbal medicine, on intestinal function following pancreaticoduodenectomy (PD) in a multicenter, randomized, double-blinded, placebo-controlled manner (JAPAN-PD study). This concomitant study investigated the effect of TJ-100 on serum cytokine levels in patients who underwent PD. Due to the fact that several clinical variables can affect the absolute values of baseline serum cytokine levels, the ratios of the cytokine levels on postoperative day (POD)3 to those on POD1 were also used for analysis. The present study enrolled 180/224 randomized patients, of whom 91 received TJ-100 and 89 received placebo. As the main findings of the analysis, Wilcoxon signed-rank test revealed no significant difference in the levels of serum cytokines between the groups; however, patients in the TJ-100 group without severe inflammatory complications exhibited significantly higher ratios of interleukin (IL)-4 (n=123), IL-9 (n=72), IL-10 (n=97), PDGF-BB (n=143) and tumor necrosis factor-α (n=135), compared with patients in the Placebo Group (P<0.05). According to the results of the present study, TJ-100 has an effect on the change in serum cytokine levels from POD1 to POD3 following PD. However, the role of different transition pattern of cytokines in postoperative recovery following PD has to be investigated by further mechanical studies focusing on these extracted cytokines (ClinicalTrials.gov; no. NCT01607307; May 30, 2012).

Overexpression of KDM5B/JARID1B is associated with poor prognosis in hepatocellular carcinoma

Background & aims

Hepatocellular carcinoma (HCC) has high potential for recurrence, even in curative operative cases. Although several molecular-targeting drugs have been applied to recurrent HCC, their effectiveness has been limited. This study therefore aims to develop novel cancer drugs through protein methylation.

Methods

We investigated the role of KDM5B/JARID1B, a member of JmjC histone demethylase, in HCC. Expression profiles of KDM5B were examined by immunohistochemical analysis in 105 HCC clinical tissue samples. To examine functional effects of KDM5B using HCC cell lines, we performed loss-of-function analysis treated with KDM5B-specific small interfering RNAs (siKDM5B).

Results

All HCC cases were divided into KDM5B-positive expression group (n=54) and negative expression group (n=51). In five-year overall survival, KDM5B-positive group had poorer prognosis than KDM5B-negative (61% vs 77%, p=0.047). KDM5B-positive group had much poorer prognosis than that of the negative group, especially in HCC derived from persistent infection of hepatitis B virus (HBV) or hepatitis C virus (HCV) (54% vs 78%, p=0.015). Multivariate analysis indicated that KDM5B was the strongest risk factor for poor prognosis, especially in HCC derived from HBV/HCV. Inhibition of KDM5B could significantly suppress HCC cell proliferation through no promotion from G1 to S phase. Real-time PCR and Western blotting demonstrated that E2F1/E2F2 were downstream genes of KDM5B.

Conclusions

Overexpression of KDM5B results in poor prognosis in HCC that especially derived from HBV/HCV. KDM5B appears to be an ideal target for the development of anti-cancer drugs.

Detection of needle tract implantation and peritoneal seeding after radiofrequency ablation using intraoperative near-infrared fluorescence system for recurrent hepatocellular carcinoma: a case report

BACKGROUND

Radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) is already fully established worldwide. Needle tract implantation and peritoneal seeding occasionally occur by RFA, and the prognosis of these cases is thought to be poor. In this study, intraoperative real-time near-infrared fluorescence (NIRF) system by indocyanine green (ICG) incidentally detected both needle tract implantation and peritoneal seeding. As the utility of this system for identification of implanted and disseminated lesions after RFA for HCC has not been widely reported, we report a case of successful detection by real-time ICG-NIRF imaging and subsequent resection.

CASE PRESENTATION

A 76-year-old man originally underwent medial sectionectomy for HCC in 2009. When repeated intrahepatic recurrence occurred, he underwent RFA and transcatheter arterial chemoembolization (TACE) for recurrent HCC twice at segment III and once at segment IV. In 2013, the second hepatectomy for recurrent HCC at segment VIII was performed. In 2016, he had recurrent HCC at segment III around a previous RFA and TACE scar; therefore, left lateral sectionectomy was planned. ICG-NIRF system was used to observe a main intrahepatic metastasis at segment III and to search for other tumors in the remnant liver. Although there was no signal on the surface of the remnant liver, tiny signals were observed in the abdominal wall and greater omentum. These tumors were on the needle tract of the previous RFA; both lesions, therefore, were resected. These tumors were pathologically proven to be HCC metastases. The patient has had no recurrence 14 months after the last hepatectomy.

CONCLUSIONS

ICG-NIRF system might be helpful in the detection of not only intrahepatic lesions but also needle tract implantations or peritoneal seeding. RFA should be avoided in patients with high risk of needle tract implantation and peritoneal seeding.

Approaches for Assessing Olfaction in Children with Autism Spectrum Disorder

Olfactory traits in individuals with autism spectrum disorder (ASD) are considered the strongest predictors of social impairment. Compared to other sensory abnormalities, olfactory abnormalities in individuals with ASD are poorly understood. In this chapter, we provide an overview of the current assessment in individuals with ASD. Several confounding factors have to be considered when conducting research on olfaction in individuals with ASD. Qualitative measures of olfaction contain only limited information about the olfactory stimuli. In addition, little systematic information is available about individual's actual uses of olfaction in daily life. Only a limited number of experimental studies have performed quantitative measurements of olfactory abnormalities in ASD. Therefore, clarifying the relationship between olfactory traits and the influence of real-life situations in a laboratory setting is very difficult. Some new methodologies for measuring olfactory traits are gradually becoming available. New methods that reveal important links between ASD and olfactory traits should be developed in the future.

Prospective validation of patient fatigue questionnaire (FACIT-F) for fatigue assessment in nab-paclitaxel plus gemcitabine therapy

Following the recent introduction of a stronger regimen for pancreatic carcinoma, patients undergoing chemotherapy present high incidences of fatigue. The feasibility and validity of evaluating fatigue by questionnaire for patients with unresectable pancreatic cancer (URPC) receiving this recent regimen of chemotherapy remains unclear. Enrolled patients completed the Functional Assessment of Cancer Therapy-Fatigue questionnaire (FACIT-F, version 4), a questionnaire regarding additional concerns, a numerical rating scale test concerning loss of appetite, an evaluation of degree of pain and sensory disorder, and the Patient Neurotoxicity Questionnaire (PNQ) before undergoing nab-paclitaxel plus gemcitabine therapy. Questionnaires and tests were completed on registration day, and then weekly during therapy over an 8-week period as the initial two cycles of continuous regimen. This trial is registered on the UMIN Clinical Trials Registry (UMIN000021758). Between April 2016 and September 2016, 10 consecutive patients with URPC, including metastatic (n=4) and locally advanced pancreatic (n=6) cancer, were registered, and scheduled for nab-paclitaxel plus gemcitabine therapy. The mean maximum values of fatigue degree increased from mean baseline values in all categories of the questionnaire (6-500%). The degree of fatigue presented a spike pattern over a 4-week scheduled period as one cycle of regimen in time-sequence diagram regarding 10/13 (77%) questionnaires. The PNQ concerning sensory/motor disorder also demonstrated a spike pattern and an increase from the baseline as the number of administrations. It is valid and feasible to assess fatigue by FACIT-F questionnaire for patients with URPC undergoing nab-paclitaxel plus gemcitabine therapy, and to detect detailed changes in accordance with scheduled cycles of chemotherapy regimen.

Is distal pancreatectomy with en-bloc celiac axis resection effective for patients with locally advanced pancreatic ductal adenocarcinoma? -Multicenter surgical group study

OBJECTIVES

We retrospectively investigated the operative outcomes of patients who underwent distal pancreatectomy (DP) for invasive pancreatic ductal adenocarcinoma (PDAC) located at the body and tail.

METHODS

Data from 395 patients with PDAC who underwent DP with margin-negative resection (R0 or R1) were collected from seven high-volume centers in Japan from 2001 to 2012. Among them, 72 patients underwent DP with en-bloc celiac axis resection (DP-CAR). The remaining 323 patients underwent conventional DP with splenectomy (DP-S). To determine the efficacy of DP-CAR, clinicopathological data were compared between the DP-CAR and the DP-S groups.

RESULTS

The DP-S group consisted mainly of patients with resectable disease (93%), and conversely, all patients in the DP-CAR group had borderline resectable or unresectable disease. The overall morbidity was significantly higher in the DP-CAR group than in the DP-S group (63% vs 47%, respectively; P = 0.017). The median survival time (MST) of the DP-CAR group was significantly shorter than that of the DP-S group (17.5 vs 28.6 months, respectively; P = 0.004). However, the MST of patients in the DP-CAR group (n = 61, 85%) who received adjuvant therapy was significantly longer than that of patients in the DP-S group (n = 65, 20%) who underwent R1 resection (21.9 vs 16.7 months, respectively; P = 0.024).

CONCLUSION

DP-CAR followed by adjuvant chemotherapy provided an acceptable overall survival rate in patients with highly advanced PDAC, but should be performed with great caution because of high morbidity. Patients with a high risk of positive surgical margins with DP-S may be candidates for DP-CAR.

Indocyanine green fluorescence imaging techniques and interventional radiology during laparoscopic anatomical liver resection (with video)

BACKGROUND

To accomplish laparoscopic anatomical liver resection, intraoperative liver segmentation is necessary. Tattooing method or Glissonian approach will be used in a similar way to that in open liver resection. Moreover, in liver segment detection, the fluorescence of indocyanine green (ICG) means it has been recognized as a useful dye. In laparoscopy, however, there are technical difficulties in performing these conventional methods, so development of new techniques is necessary for liver segment identification. We report a pilot study using interventional radiology technique for laparoscopic intraoperative liver segmentation.

METHODS

Just prior to liver parenchymal resection, angiography was performed using a hybrid operation room. A catheter was inserted from the right femoral artery into the targeted arterial branch. After confirming the perfusion area by arteriography, embolic solution containing ICG was injected, and the branch was embolized. ICG fluorescence was observed by PINPOINT, a near-infrared imaging system.

RESULTS

Immediately after embolic solution injection, we were able to observe ICG fluorescence on the surface of the liver to be resected. This visual effect continued during liver parenchymal resection. We were able to confirm the intra-parenchymal boundary by observing ICG fluorescence on the cut surface of the resecting side and accomplished precise anatomical liver resection.

CONCLUSIONS

Our novel technique provides advances in laparoscopic anatomical liver resection performance. As two-dimensional laparoscopy lacks depth perception, additional visual information, such as ICG fluorescence imagery, is helpful as a navigation tool for precise laparoscopic anatomical liver resection.

Reinforced staplers for distal pancreatectomy

PURPOSE

The safety and efficacy of reinforced staplers during distal pancreatectomy (DP) remain controversial because of the small sample size. This multicenter single-arm prospective study aims to evaluate the safety and efficacy of reinforced staplers with bioabsorbable material during DP.

METHODS

Between October 2014 and August 2015, 121 patients scheduled for DP were enrolled in this study at 11 institutions in Japan. The primary endpoint was the incidence of clinically relevant pancreatic fistula. Protocol treatment was defined as "distal pancreatectomy using reinforced staplers."

RESULTS

Per-protocol analysis of 105 patients was performed; 16 of the patients were excluded based on discontinuation of protocol treatment criteria. Clinically relevant pancreatic fistula occurred in 13 (12.4%) of 105 patients. The overall morbidity rate was 29.5% (31 of 105 patients) and severe complication (Clavien classification IIIa or more) was 10.5% (11/105). Mortality rate was 0%, although reoperations were performed on two patients (1.9%). Multivariate logistic regression analysis of independent risk factors for clinically relevant pancreatic fistula after DP using reinforced stapler closure was operative time more than 240 min (P = 0.047, odds ratio 5.79), registration numbers less than 10 (P = 0.046, odds ratio 13.01), and staple line hemorrhage (P = 0.003, odds ratio 16.34).

CONCLUSION

This study confirms the safety of reinforced staplers for pancreatic stump closure during DP. However, the efficacy of reinforced staplers for decreasing clinically relevant pancreatic fistula could not be drawn from this study.

TRIAL REGISTRATION

This prospective study was registered with ClinicalTrials.gov (NCT02270554) and UMIN Clinical Trial Registry (UMIN000015384).