野田 弘志

OBJECTIVES: Aberrant hypomethylation of long interspersed nucleotide element-1 (LINE-1) and satellite alpha (SATa) in pancreatic cancer cells increases malignant potential. In addition, circulating tumor DNA (ctDNA) is likely to be associated with micrometastasis and appears more frequently in advanced pancreatic ductal adenocarcinoma (PDAC) patients. In this study, we elucidated the relationship between these factors. MATERIALS AND METHODS: A total of 37 patients with PDAC who underwent surgery or first-line chemotherapy were selected in 2014-2017. DNA extracted from surgical or biopsy specimens was used to calculate the relative demethylation levels (RDLs) of the LINE-1 and SATa using methylation-specific quantitative PCR. KRAS -mutated ctDNA was monitored using droplet digital PCR. Receiver operating characteristic curve analysis was performed to determine the cut-off values of LINE-1 and SATa RDLs before and after surgery or during first-line chemotherapy based on ctDNA status (presence or absence). RESULTS: Median LINE-1 RDL before treatment was higher in patients with ctDNA than in those without, but these cut-off values (LINE-1 ≥0.058 and 0.055) peritreatments did not link to prognosis ( P =0.762 and 0.933). Conversely, the cut-off value of SATa RDL (SATa ≥0.150) based on ctDNA status after treatments showed a significant association with poor prognosis ( P =0.038). On the other hand, the cut-off value of SATa RDL (SATa ≥0.155) before treatment was found to have no association with prognosis ( P =0.408). CONCLUSIONS: Evaluating pretreatment tumor DNA hypomethylation together with KRAS -mutated ctDNA status after surgery or initiation of first-line chemotherapy is associated with poor prognosis in PDAC.

BACKGROUND: Pancreaticoduodenectomy (PD) is highly invasive and is followed by frequent postoperative complications that may cause a decrease in skeletal muscle volume in patients. Although the association between a decreased skeletal muscle volume and quality of life (QOL) and the patient prognosis has been revealed, the dynamics of the decrease in skeletal muscle volume after PD have not been well studied. METHODS: Two hundred fourteen consecutive patients who underwent elective PD at our hospital between January 2013 and April 2020 were reviewed. The psoas muscle (PM) volume at the third lumbar vertebra (L3) and quadriceps femoris muscle (QFM) volume at the lesser trochanter on CT images before PD and at 7 days, 6 months, and 12 months after PD were measured to evaluate the skeletal muscle volume dynamics after PD. We then explored the factors associated with a decrease in skeletal muscle after PD using a stepwise regression analysis. RESULTS: In 176 patients who underwent PD, the skeletal muscle volume decreased by approximately 10% within 7 days after PD and was sustained for 12 months in both the PM and QFM. We also identified the following risk factors for a decreased skeletal muscle volume at postoperative month 12 after PD: pancreatic adenocarcinoma (β = 4.9, p < 0.010), high body mass index (β = -4.13, p = 0.002), clinically relevant postoperative pancreatic fistula (β = 3.53, p = 0.003), and recurrence within 12 months after PD (β = 2.94, p = 0.024). CONCLUSIONS: Further studies to develop appropriate perioperative nutritional management and muscle training are warranted to maintain the skeletal muscle volume after PD to improve the patient prognosis and QOL.

BACKGROUND: In anatomical segment 7 (S7) segmentectomy, the inferior right hepatic vein (IRHV) can be a useful landmark to identify the portal branch of segment 7 (P7); however, the positional relationship between the IRHV and the posterior portal branch has not been investigated. PATIENTS AND METHODS: We reviewed 203 patients who underwent preoperative multi-detector CT at Jichi Saitama Medical Center from 2022 to 2024. We processed 3D images and evaluated the running patterns concerning the IRHV, and the posterior portal vein and the right hepatic vein (RHV). The IRHV was classified as S6 (IRHV running inside S6 only), S7 (IRHV running inside S7 only), or S6/S7 (the vein courses along the intersegmental plane separating P6 and P7). RESULTS: IRHVs were present in 44.8% of patients and were classified as S6 in 11.0%, S7 in 17.6%, and S6/S7 in 71.4%. Among patients with IRHVs, 92.3% had either an IRHV or an RHV running along the intersegmental plane separating P6 and P7, compared with 24.1% of patients without IRHVs (p < 0.01). CONCLUSIONS: Most IRHVs were classified as S6/S7. When the IRHV does not serve as a landmark, the RHV may provide an alternative anatomical landmark for identifying P7 during anatomical S7 segmentectomy.

INTRODUCTION: Spontaneous tumor regression (STR) is a rare phenomenon in which cancer cells partially or completely disappear without treatment. We report a case of intrahepatic cholangiocarcinoma demonstrating STR following endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA). CASE PRESENTATION: A 77-year-old male presented with acute cholecystitis 1 day after percutaneous coronary intervention for acute myocardial infarction. Conservative treatment and endoscopic retrograde gallbladder drainage were performed due to antiplatelet therapy. Cytology of bile juice unexpectedly revealed adenocarcinoma. Further imaging, including CT and mapping biopsy, failed to detect a tumor. Laparoscopic cholecystectomy with gallbladder bed resection showed no histological evidence of malignancy. Four months later, surveillance CT revealed a 15 × 15 mm lesion in segment 3 of the liver. EUS-FNA confirmed adenocarcinoma. Laparoscopic left lateral resection was performed; however, no viable cancer cells were identified, and the lesion was replaced by epithelioid granulomas. Immunohistochemistry demonstrated dense infiltration of CD8-positive cytotoxic T cells, suggesting an immune-mediated regression of the tumor. CONCLUSIONS: This case highlights the possibility of tumor regression in intrahepatic adenocarcinoma following EUS-FNA, potentially triggered by an immune response.

BACKGROUND/PURPOSE: The dynamics of bone mineral density (BMD) decrease after pancreaticoduodenectomy in long-term survivors and its risk factors have scarcely been studied. METHODS: Seventy-nine patients who underwent pancreaticoduodenectomy and survived for > 5 years were included in this study. We measured the mean CT Hounsfield Unit [HU] values of the anterior trabecular portion of the 1st through 4th lumbar vertebral bodies on a single axial CT scan before pancreaticoduodenectomy and at 1, 2, 3, 4, and 5 years postoperatively. The mean HU values for the 1st to 4th lumbar vertebrae were used as the BMD index. RESULTS: The percentage annual BMD index decrease after pancreaticoduodenectomy was as follows: before pancreaticoduodenectomy and 1st year postoperatively, 18.9% (p < 0.001); 1-2 years postoperatively, 3.9% (p = 0.014); and 4-5 years postoperatively, 3.9% (p = 0.030). A multivariate analysis revealed that the presence of preoperative obstructive jaundice (β = -5.2; 95% confidence interval -9.6 to -0.7, p = 0.023) and long postoperative hospital stay (β = -7.0; 95% confidence interval - 13.4 to -0.7, p = 0.031) were significantly associated with BMD index decrease until the 1st year after pancreaticoduodenectomy. CONCLUSIONS: This study identified a rapid decrease of BMD after pancreaticoduodenectomy. Preoperative obstructive jaundice and long postoperative hospital stay are significant risk factors for decreased BMD after pancreaticoduodenectomy.

At our institution, scrub nurses leave the surgical field during the console time for robotic surgeries to attend to other duties. The first assistant then assumes their responsibilities, allowing for efficient use of staff time and resources. This practice improves teamwork and can be presented as a cost-saving measure for hospital administrations.

BACKGROUND: While seasonality of hospital-acquired infections, including incisional SSI after orthopaedic surgery, is recognized, the seasonality of incisional SSI after general and gastroenterological surgeries remains unclear. STUDY DESIGN: This retrospective single-institute observational study analysed the seasonality and risk factors of incisional SSI after general and gastroenterological surgeries using univariate and multivariable analyses. The evaluated variables included age, sex, surgical approach, surgical urgency, operation time, wound classification, and the American Society of Anesthesiologists physical status (ASA-PS). RESULTS: 8,436 patients were enrolled. General surgeries (n=2,241) showed a pronounced SSI incidence in summer (3.9%; odds ratio [OR] 1.87; 95% confidence interval [CI] 1.05-3.27; p=0.025) compared to other seasons (2.1%). Conversely, gastroenterological surgeries (n=6,195) showed a higher incidence in winter (8.3%; OR 1.38; 95% CI 1.10-1.73; p=0.005) than in other seasons (6.1%). Summer for general surgery (OR 1.90; 95% CI 1.12-3.24; p=0.018) and winter for gastroenterological surgery (OR 1.46; 95% CI 1.17-1.82; p=0.001) emerged as independent risk factors for incisional SSI. Open surgery (OR, 2.72; 95% CI 1.73-4.29, p<0.001) and an ASA-PS score ≥3 (OR, 1.64; 95% CI 1.08-2.50, p=0.021) were independent risk factors for incisional SSI in patients undergoing gastroenterological surgery during winter. CONCLUSION: Seasonality exists in the incisional SSI incidence following general and gastroenterological surgeries. Recognizing these trends may help enhance preventive strategies, highlighting the elevated risk in summer for general surgery and in winter for gastroenterological surgery.

PURPOSE: Mesopancreas resection is a crucial but difficult procedure when performing pancreaticoduodenectomy. This study evaluated the influence of mesopancreas thickness on surgical outcomes in patients undergoing pancreaticoduodenectomy. METHODS: We measured the thickness of the fat tissue on the right side of the superior mesenteric artery from the dorsal margin of the confluence of the superior mesenteric vein and portal vein to the ventral margin of the left renal vein on preoperative contrast-enhanced computed tomography and defined it as the mesopancreas thickness. We evaluated the correlation between mesopancreas thickness and intraoperative and postoperative variables in 357 patients who underwent pancreaticoduodenectomy. RESULTS: Multivariate analysis revealed that a thick mesopancreas was significantly associated with a long operative time (β = 10.361; 95% confidence interval, 0.370-20.353, p = 0.042), high estimated blood loss (β = 36.038; 95% confidence interval, -27.192-99.268, p = 0.013), and a low number of resected lymph nodes (β = -1.551; 95% confidence interval, -2.662--0.439, p = 0.006). This analysis further revealed that thick mesopancreas was a significant risk factor for overall morbidity (odds ratio 2.170; 95% confidence interval 1.340-3.520, p = 0.002), major morbidity (odds ratio 2.430; 95% confidence interval 1.360-4.340, p = 0.003), and a longer hospital stay (β = 2.386; 95% confidence interval 0.299-4.474, p = 0.025). CONCLUSION: A thick mesopancreas could predict a longer operation time, higher estimated blood loss, fewer resected lymph nodes, more frequent overall and major morbidities, and a longer hospital stay in patients who underwent pancreaticoduodenectomy more precisely than the body mass index.

BACKGROUND: The recent guidelines from the European and American Hernia Societies recommend a continuous small-bite suturing technique with slowly absorbable sutures for fascial closure of midline abdominal wall incisions to reduce the incidence of wound complications, especially for incisional hernia. However, this is based on low-certainty evidence. We could not find any recommendations for skin closure. The wound closure technique is an important determinant of the risk of wound complications, and a comprehensive approach to prevent wound complications should be developed. METHODS: We propose a single-institute, prospective, randomized, blinded-endpoint trial to assess the superiority of the combination of continuous suturing of the fascia without peritoneal closure and continuous suturing of the subcuticular tissue (study group) over that of interrupted suturing of the fascia together with the peritoneum and interrupted suturing of the subcuticular tissue (control group) for reducing the incidence of midline abdominal wall incision wound complications after elective gastroenterological surgery with a clean-contaminated wound. Permuted-block randomization with an allocation ratio of 1:1 and blocking will be used. We hypothesize that the study group will show a 50% reduction in the incidence of wound complications. The target number of cases is set at 284. The primary outcome is the incidence of wound complications, including incisional surgical site infection, hemorrhage, seroma, wound dehiscence within 30 days after surgery, and incisional hernia at approximately 1 year after surgery. DISCUSSION: This trial will provide initial evidence on the ideal combination of fascial and skin closure for midline abdominal wall incision to reduce the incidence of overall postoperative wound complications after gastroenterological surgery with a clean-contaminated wound. This trial is expected to generate high-quality evidence that supports the current guidelines for the closure of abdominal wall incisions from the European and American Hernia Societies and to contribute to their next updates. TRIAL REGISTRATION: UMIN-CTR UMIN000048442. Registered on 1 August 2022. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000055205.

PURPOSE: Midline abdominal incisions (MAIs) are widely used in both open and minimally invasive surgery. Incisional hernia (IH) accounts for most long-term postoperative wound complications. This study explored the risk factors for IH due to MAI in patients with clean-contaminated wounds after elective gastroenterological surgery. METHODS: The present study targeted patients enrolled in 2 randomized controlled trials to evaluate the efficacy of intraoperative interventions for incisional SSI prevention after gastroenterological surgery for clean-contaminated wounds. The patients were reassessed, and pre- and intraoperative variables and postoperative outcomes were collected. IH was defined as any abdominal wall gap, regardless of bulge, in the area of a postoperative scar that was perceptible or palpable on clinical examination or computed tomography according to the European Hernia Society guidelines. The risk factors for IH were identified using univariate and multivariate analyses. RESULTS: The study population included 1,281 patients, of whom 273 (21.3%) developed IH. Seventy-four (5.8%) patients developed incisional SSI. Multivariate logistic regression analysis revealed that female sex (odds ratio [OR], 1.39; 95% confidence interval [CI] 1.03-1.86, p = 0.031), high preoperative body mass index (OR, 1.81; 95% CI 1.19-2.77, p = 0.006), incisional SSI (OR, 2.29; 95% CI 1.34-3.93, p = 0.003), and postoperative body weight increase (OR, 1.49; 95% CI 1.09-2.04, p = 0.012) were independent risk factors for IH due to MAI in patients who underwent elective gastroenterological surgery. CONCLUSION: We identified postoperative body weight increase at one year as a novel risk factor for IH in patients with MAI after elective gastroenterological surgery.

BACKGROUND: Clean-contaminated wounds should be the main target for reducing the burden of harm caused by surgical site infection after gastroenterological surgery. METHODS: The present study targeted 1,973 patients enrolled in 2 randomized controlled trials to evaluate the efficacy of intraoperative interventions for incisional surgical site infection prevention after gastroenterological surgery with clean-contaminated wounds. Patients were reassessed, and preoperative and postoperative variables were collected. Risk factors for surgical site infection were identified by univariate and multivariate analyses. RESULTS: The study population included 1,878 patients, among whom 213 (11.3%) developed overall surgical site infection and 119 (6.3%) developed incisional surgical site infection. A multivariate analysis revealed that steroid or immunosuppressant use (odds ratio 3.03; 95% confidence interval 1.37-6.73, P = .0064), open surgery (odds ratio 1.77; 95% confidence interval 1.11-2.83, P = .0167), and long operative time (odds ratio 2.31; 95% confidence interval 1.5-3.56, P < .001) were independent risk factors for incisional surgical site infection. Steroid or immunosuppressant use (odds ratio 2.62; 95% confidence interval 1.29-5.33, P = .0078), open surgery (odds ratio 2.13; 95% confidence interval 1.44-3.16, P < .001), and long operative time (odds ratio 2.92; 95% confidence interval 2.08-4.10, P < .001) were also independent risk factors for overall surgical site infection in the multivariate analysis. Furthermore, a multivariate analysis revealed that a long operative time (odds ratio 3.21; 95% confidence interval 1.69-6.1, P = .00378) was an independent risk factor for incisional surgical site infection in patients who underwent laparoscopic surgery. CONCLUSION: Even under current measures for surgical site infection prevention, surgeons should continue to make efforts to appropriately expand the indication of laparoscopic surgery and to reduce operative times even when performing laparoscopic surgery.

BACKGROUND/PURPOSE: Patients who receive preoperative biliary drainage (PBD) and biliary reconstruction are most at risk for incisional surgical site infection (SSI) in major hepatobiliary-pancreatic (HBP) surgery. METHODS: We evaluated 72 patients with PBD who underwent major HBP surgery and received intraoperative wound irrigation (IOWI) with saline and standard sutures between March 2014 and March 2017 (Cohort 1) and 63 patients with PBD who underwent major HBP surgery and received IOWI with aqueous 10% povidone-iodine and antibacterial sutures between June 2019 and February 2022 (Cohort 2). We compared the incidence of incisional SSI between the two cohorts. RESULTS: Twenty-seven (20.0%) of 135 patients developed incisional SSIs. The rate of current smoking was more frequent in patients who developed incisional SSIs than in those who did not (37.0% vs. 14.8%, p = .012). A total of 18 (25%) of 72 patients developed incisional SSI in Cohort 1, and nine (14.3%) of 63 developed incisional SSI in Cohort 2. Cohort 2 had a 10% lower incidence of incisional SSI than Cohort 1, a nonsignificant difference (p = .09). CONCLUSION: The implementation of IOWI with aqueous 10% PVP-I and antibacterial sutures failed to significantly reduce the incidence of incisional SSI in comparison to IOWI with saline and standard sutures in major HBP surgery.

OBJECTIVE: This trial evaluated the superiority of intraoperative wound irrigation (IOWI) with aqueous povidone-iodine (PVP-I) compared to that with saline for reducing the incidence of surgical site infection (SSI). BACKGROUND: IOWI with aqueous PVP-I is recommended for the prevention of SSI by the World Health Organization and Centers for Disease Control and Prevention, although the evidence level is low. METHODS: This single-institute in Japan, prospective, randomized, blinded-endpoint trial was conducted to assess the superiority of IOWI with aqueous PVP-I in comparison to IOWI with saline for reducing the incidence of SSI in clean-contaminated wounds after gastroenterological surgery. Patients ≥20 years old were assessed for eligibility, and eligible participants were randomized at a 1:1 ratio using a computer-generated block randomization. In the study group, IOWI was performed for one minute with 40 mL of aqueous 10% PVP-I before skin closure. In the control group, the procedure was performed with 100 mL of saline. Participants, assessors, and analysts were masked to the treatment allocation. The primary outcome was the incidence of incisional SSI in the intention-to-treat set. RESULTS: Between June 2019 and March 2022, 941 patients were randomized to the study group (473 patients) or the control group (468 patients). The incidence of incisional SSI was 7.6% in the study group and 5.1% in the control group (risk difference 0.025, 95% CI -0.006 to 0.056; risk ratio 1.484, 95% CI 0.9 to 2.448; P =0.154). CONCLUSION: The current recommendation of IOWI with aqueous PVP-I should be reconsidered.

INTRODUCTION: Surgical site infection (SSI) is one of the most common complications after gastrointestinal surgery, with a reported incidence of approximately 10%-25%, which is higher than the rates after other types of surgery. Intraoperative wound irrigation (IOWI) is a simple intervention for SSI prevention, and recent studies have reported that IOWI with aqueous povidone-iodine (PVP-I) is significantly more effective at reducing the incidence of SSI than saline. However, the evidence level of previous trials evaluating the efficacy of aqueous PVP-I solution for preventing SSI has been low. METHODS AND ANALYSES: We propose a single-institute, prospective, randomised, blinded-endpoint trial to assess the superiority of IOWI with aqueous 10% PVP-I solution compared with normal saline for reducing SSI in clean-contaminated wounds after elective gastrointestinal surgery. In the study group, IOWI with 40 mL of aqueous 10% PVP-I solution is performed for 1 min before skin suture, and in the control group, IOWI with 100 mL of saline is performed for 1 min before skin suture. We hypothesise that IOWI with aqueous 10% PVP-I solution will achieve a 50% reduction in the incidence of SSIs. The target number of cases is set at 950. The primary outcome is the incidence of incisional SSI up to postoperative day 30 and will be analysed in the modified intention-to-treat set. ETHICS AND DISSEMINATION: This trial was designed and is being conducted by Saitama Medical Center, Jichi Medical University, with approval from the Bioethics Committee for Clinical Research, Saitama Medical Center, Jichi Medical University. Participant recruitment began in June 2019. The final results will be reported in international peer-reviewed journals immediately after trial completion. TRIAL REGISTRATION NUMBER: UMIN000036889.

INTRODUCTION: The drain output volume (DOV) after pancreaticoduodenectomy (PD) is an easily assessable indicator in clinical settings. We explored the utility of the DOV as a possible warning sign of complications after PD. METHODS: A total of 404 patients undergoing PD were considered for inclusion. The predictability of the DOV for overall morbidity, major complications, intraabdominal infection (IAI), clinically relevant (CR) postoperative pancreatic fistula (POPF), CR delayed gastric emptying (DGE), CR chyle leak (CL), and CR post-pancreatectomy hemorrhaging (PPH) was evaluated. RESULTS: One hundred (24.8%) patients developed major complications, and 131 (32.4%) developed IAI. Regarding CR post-pancreatectomy complications, 75 (18.6%) patients developed CR-POPF, 23 (5.7%) developed CR-DGE, 20 (5.0%) developed CR-CL, and 28 (6.9%) developed CR-PPH. The median DOV on postoperative day (POD) 1 and POD 3 was 266 and 234.5 ml, respectively. A low DOV on POD 1 was an independent predictor of CR-POPF, and a high DOV on POD 3 was an independent predictor of CR-CL. A receiver operating characteristics (ROC) analysis revealed that the DOV on POD 1 had a negative predictive value (area under the curve [AUC] 0.655, sensitivity 65.0%, specificity 65.3%, 95% confidence interval [CI]: 0.587-0.724), with a calculated optimal cut-off value of 227 ml. An ROC analysis also revealed that the DOV on POD 3 had a positive predictive value (AUC 0.753, sensitivity 70.1%, specificity 75.0%, 95% CI: 0.651-0.856), with a calculated optimal cut-off value of 332 ml. CONCLUSION: A low DOV on POD 1 might be a postoperative warning sign for CR-POPF, similar to high drain amylase (DA) on POD 1, high DA on POD 3, and high CRP on POD 3. When the DOV on POD 1 after PD was low, surgeons should evaluate the reasons of a low DOV. A high DOV on POD 3 was a postoperative warning sign CR-CL, and might require an appropriate management of protein loss.

BACKGROUND: We investigated the risk factors for clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct. METHODS: We investigated a total of 354 patients who underwent pancreaticoduodenectomy. The diameter of the main pancreatic duct, the shortest distance from the body surface to the pancreas (the pancreatic depth), and the computed tomography attenuation index (the difference between the pancreatic and splenic computed tomography attenuation) were measured in preoperative computed tomography. RESULTS: One hundred eighty-one (51.1%) patients had a nondilated main pancreatic duct, and 50 (27.6%) of the 181 patients with a nondilated main pancreatic duct developed a clinically relevant postoperative pancreatic fistula. Univariate analyses revealed that the calculated body mass index (≥21.8 kg/m2) (P = .004), deep pancreas (pancreatic depth ≥51.2 mm) (P = .001), and low computed tomography attenuation index (≤-3.8 Hounsfield units) (P = .02) were significant risk factors for clinically relevant postoperative pancreatic fistula. The multivariate logistic regression analysis revealed that deep pancreas (odds ratio 2.370; 95% confidence interval 1.0019-5.590; P = .049) was an independent risk factor for clinically relevant postoperative pancreatic fistula. Among patients with a nondilated main pancreatic duct, deep pancreas (in comparison to patients without deep pancreas) was associated with male sex (72.7% vs 54.9%; P = .016), higher body mass index (22.5 kg/m2 vs 19.6 kg/m2; P < .001), a history of diabetes mellitus (24.5% vs 8.5%; P = .006), a lower computed tomography attenuation index (-9.6 Hounsfield units vs -4.6 Hounsfield units; P = .007), a longer operative time (454 minutes vs 420 minutes; P = .007), and a higher volume of intraoperative blood loss (723 mL vs 500 mL; P < .001), respectively. CONCLUSION: Deep pancreas may be an important parameter associated with significant risk factors for clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct.

BACKGROUND: /Objectives: The objectives of this study were to identify the factors affecting patients' survival and the characteristics of five-year survivors of pancreatic ductal adenocarcinoma (PDAC) after pancreatectomy as well as to clarify the correlation between the development of postoperative complications and a five-year survival. METHODS: A total of 104 patients underwent pancreatectomy for PDAC between April 2005 and March 2013 with curative intent. Patients who survived for more than five years after pancreatectomy were classified as long-term survivors. Sixteen demographic and clinical variables and 10 pathological variables were comprehensively assessed for their associations with the patients' survival time and long-term survival. RESULTS: The presence of preoperative comorbidity (OR: 1.65, 95% CI 1.02-2.67, p = 0.042), postoperative overall complications (OR: 1.78, 95% CI 1.03-3.10, p = 0.041), a lymph node positivity ratio of ≥0.2 (OR: 3.04, 95% CI 1.51-6.11, p = 0.002), and portal invasion (OR: 2.58, 95% CI 1.48-4.49, p = 0.001) were identified as independent factors affecting the patients' survival. The absence of postoperative overall complications was identified as an independent factor related to long-term survival in the multivariate analysis (OR: 0.08, 95% CI 0.01-0.82, p = 0.034). CONCLUSIONS: The presence of preoperative comorbidity, postoperative overall complications, LNR ≥0.2, and portal invasion were prognostic factors affecting the patients' survival, and avoiding postoperative complications after pancreatectomy might contribute to the long-term survival of PDAC patients after pancreatectomy. The further improvement of surgical procedures and perioperative care in order to reduce the rate of postoperative complications should be attempted.

BACKGROUND/OBJECTIVES: The aims of this study were to clarify the effect of preoperative biliary drainage (PBD) on postoperative outcomes and the role of preoperative intentional exchange from endoscopic nasobiliary drainage (ENBD) to endoscopic retrograde biliary drainage (ERBD) for patients waiting to undergo pancreaticoduodenectomy (PD). METHODS: We evaluated the effect of PBD and intentional exchange of PBD on the perioperative variables in 292 patients. RESULTS: A total of 179 (61.3%) of 292 patients received PBD. There was no marked difference in the postoperative outcomes between the patients who did and did not receive PBD. Among the 160 patients who initially received endoscopic PBD, 10 (6.3%) underwent stent exchange for stent dysfunction, 59 (36.9%) who did not develop stent dysfunction underwent intentional stent exchange from ENBD to ERBD (bridge PBD group), and 91 (56.9%) did not receive any stent exchange (unchanged PBD group). The bridge PBD group had a longer duration of PBD (37 days) (p < 0.001) and a shorter preoperative hospital stay after PBD (32 days) (p < 0.001) than the unchanged PBD group (25 and 46 days, respectively); however, there were no significant differences in the postoperative variables. The incidence of stent exchange due to stent dysfunction in the bridge PBD group (11.9%) was lower than that in patients who initially received ERBD (36.0%) (p = 0.015). CONCLUSIONS: Bridge PBD worked well for extending the duration of PBD without worsening the postoperative outcomes after PD.

Pancreatectomy might confer a survival benefit in patients with metastatic tumors of the pancreas (MTPs); however, the optimal treatment for MTP has not been established. We reviewed six patients with MTP undergoing pancreatectomy and discussed the clinical features, surgical treatment, and survival. The sites of primary cancer included renal cell carcinoma (RCC) (n = 5; 83.3%) and rectal cancer (n = 1; 16.7%). The median interval between the resection of the primary site and the development of MTP was 157 months (range, 16-180 months). Three (60.0%) of the five cases of MTP-originating RCC and a MTP-originating rectal cancer, biopsy was performed under endoscopic ultrasonography guidance and MTP was pathologically diagnosed. All patients with MTP originating from RCC have remained alive for 3, 13, 18, 18, and 113 months without recurrence after pancreatectomy. In contrast, the patient with MTP originating from rectal cancer developed multiple liver metastases at 7 months after pancreatectomy, and then underwent chemotherapy. A preoperative pathological diagnosis using biopsy under endoscopic ultrasonography guidance was indispensable for the treatment of MTP. Pancreatectomy for MTP conferred a survival benefit in patients with metastatic RCC, whereas a combination of pancreatectomy and chemotherapy might be necessary to improve the prognosis of patients with metastatic colorectal cancer.

BACKGROUND: Surgical site infection is one of the most common postoperative complications after gastroenterologic surgery. This study investigated the effect of triclosan-coated sutures in decreasing the incidence of surgical site infections after abdominal wall closure in gastroenterologic surgery. METHODS: A prospective, double-blind, randomized, controlled parallel adaptive group-sequential superiority trial was conducted from March 2014 to March 2017 in a single center. Eligible patients were those who underwent gastroenterologic surgery. Patients were allocated randomly to receive either abdominal wall closure with triclosan-coated sutures (the study group) or sutures without triclosan (the control group). The primary end point was the incidence of superficial or deep surgical site infections within 30 days after operation. This study was registered with the University Hospital Medical Information Network-Clinical Trials Registry (http://www.umin.ac.jp/ctr/), identification number UMIN000013054. RESULTS: A total of 1,013 patients (study group, 508 patients; control group, 505 patients) were analyzed by a modified intention-to-treat approach. The wounds in 990 (97.7%) of the 1,013 patients were classified as clean-contaminated. The primary end point (incidence of superficial or deep surgical site infections) was 35 (6.9%) of 508 patients in the study group and 30 (5.9%) of 505 in the control group. The incidence of surgical site infections did not differ markedly between the 2 groups (95% confidence interval: 0.686-2.010, P = .609). Of the 65 infections, 42 (64.6%) were superficial surgical site infections, with similar frequencies in the 2 groups, and 23 (35.4%) were deep surgical site infections, again with similar frequencies in the 2 groups. CONCLUSION: Triclosan-coated sutures did not decrease the incidence of surgical site infections after abdominal wall closure in gastroenterologic surgery.