野田 弘志

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.

Molecular assessment using circulating tumor DNA (ctDNA) has not been well-defined. We recruited 61 pancreatic cancer (PC) patients who underwent initial computed tomography (CT) imaging study during first-line chemotherapy. Initial molecular assessment was performed using droplet digital PCR and defined as the change in KRAS-mutated ctDNA before and after treatments, which was classified into five categories: mNT, molecular negative; mCR, complete response; mPR, partial response; mSD, stable disease; mPD, progressive disease. Of 61 patients, 14 diagnosed with PD after initial CT imaging showed significantly worse therapeutic outcomes than 47 patients with disease control. In these 47 patients, initial molecular assessment exhibited significant differences in therapeutic outcomes between patients with and without ctDNA (mPD + mSD vs. mCR + mNT; 13.2 M vs. 21.7 M, P = 0.0029) but no difference between those with mPD and mSD + mCR + mNT, suggesting that the presence of ctDNA had more impact on the therapeutic outcomes than change in its number. Multivariate analysis revealed that it was the only independent prognostic factor (P = 0.0405). The presence of ctDNA in initial molecular assessment predicted early tumor progression and identified PC patients more likely to benefit from chemotherapy.

A 66-year-old man underwent a single endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) session and distal pancreatectomy for the pancreatic body adenocarcinoma measuring 12 mm in diameter. At 3 years after surgery, we diagnosed needle tract seeding (NTS) and performed total gastrectomy. NTS can occur with small tumors or after a single session of EUS-FNA.

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.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most cancers. Its 5-year survival rate is very low. The recent induction of neoadjuvant chemotherapy and improvements in chemotherapy for patients with pancreatic cancer have resulted in improved survival outcomes. However, the prognosis of pancreatic cancer is still poor. To dramatically improve the prognosis, we need to develop more tools for early diagnosis, treatment selection, disease monitoring, and response rate evaluation. Recently, liquid biopsy (circulating free DNA, circulating tumor DNA, circulating tumor cells, exosomes, and microRNAs) has caught the attention of many researchers as a new biomarker that is minimally invasive, confers low-risk, and displays an overall state of the tumor. Thus, liquid biopsy does not employ the traditional difficulties of obtaining tumor samples from patients with advanced PDAC to investigate their molecular biological status. In addition, it allows for long-term monitoring of the molecular profile of tumor progression. These could help in identifying tumor-specific alterations that use the target structure for tailor-made therapy. Through this review, we highlighted the latest discoveries and advances in liquid biopsy technology in pancreatic cancer research and showed how it can be applied in clinical practice.

Genome‑wide DNA hypomethylation is the most common molecular feature in human cancers associated with chromosomal instability (CIN), which is involved in the mechanisms that regulate pancreatic cancer (PC) metastasis. It was investigated whether genome‑wide DNA hypomethylation affects the phenotype in PC via CIN in vitro, and its significance on the biological behavior of PC was verified. The relative demethylation level (RDL) of long interspersed nucleotide element‑1 (LINE‑1) in human PC cell lines was used to characterize DNA hypomethylation using methylation‑specific quantitative (q)PCR. CIN was estimated by changes in chromosomal copy number using comparative genomic hybridization analysis. Abnormal segregation of chromosomes was assessed by immunocytochemistry, and the DNA damage response was evaluated using the number of anti‑γH2AX positive cells. Invasion ability was assessed using a Matrigel invasion assay. Clinical specimens from 49 patients with PC who underwent curative surgery were evaluated for a correlation of DNA hypomethylation with clinical outcome. Successful induction of genome‑wide DNA hypomethylation in PC cells led to copy number changes in specific chromosomal regions. The number of cells with abnormal segregation of chromosomes significantly increased with the number of anti‑γH2AX positive cells. The invasive potential of these cells also significantly increased. The occurrence of occult distant metastasis in the clinical specimens and receiver operating characteristic analysis clearly identified those who were and were not likely to have occult distant metastasis, with high LINE‑1 RDL significantly correlated with the presence of occult distant metastasis (P=0.035) and poor prognosis (P=0.048). The significance of genome‑wide DNA hypomethylation on the biological behavior of PC, which promotes a more invasive phenotype via CIN in vitro and predicts the susceptibility to occult distant metastasis and poor prognosis in patients with PC was revealed.

近年、CA19-9などの既存の腫瘍マーカーに代わるバイオマーカーとして注目されている血中の循環腫瘍DNA(circulating tumor DNA:ctDNA)の検索、いわゆる"リキッドバイオプシー"はデジタルPCRや次世代シーケンスなどの技術の進歩によりさまざまな浸潤がんにおいてその有用性が示されてきた。リキッドバイオプシーは血液や尿などの体液を利用することから内視鏡や経皮的生検に比較すると低侵襲であるため、複数回採取し、長期的なモニタリングを行うことでリアルタイムに腫瘍動態を捉えることが可能である。われわれはdriver遺伝子であるKRAS変異は膵癌の約90%に見出され、さらに腫瘍内におけるKRAS変異のheterogeneityはごく少数であることに着目し、切除不能膵癌患者におけるKRAS変異型ctDNAの長期的モニタリングを行った。本稿では切除不能膵癌におけるctDNAの有用性をCA19-9とも比較しながら解説する。(著者抄録)

Despite the acceptance of carbohydrate antigen 19-9 (CA19-9) as a valuable predictor for the prognosis of pancreatic ductal adenocarcinoma (PDAC), its cutoff value remains controversial. Our previous study showed a significant correlation between CA19-9 levels and the presence of KRAS-mutated ctDNA in the blood of patients with PDAC. Based on this correlation, we investigated the optimal cutoff value of CA19-9 before surgery. Continuous CA19-9 values and KRAS-mutated ctDNAs were monitored in 22 patients with unresectable PDAC who underwent chemotherapy between 2015 and 2017. Receiver operating characteristic curve analysis identified 949.7 U/mL of CA19-9 as the cutoff value corresponding to the presence of KRAS-mutated ctDNA. The median value of CA19-9 was 221.1 U/mL. Subsequently, these values were verified for their prognostic values of recurrence-free survival (RFS) and overall survival (OS) in 60 patients who underwent surgery between 2005 and 2013. Multivariate analysis revealed that 949.7 U/mL of CA19-9 was an independent risk factor for OS and RFS in these patients (P = 0.001 and P = 0.010, respectively), along with lymph node metastasis (P = 0.008 and P = 0.017), unlike the median CA19-9 level (P = 0.150 and P = 0.210). The optimal CA19-9 level contributes to the prediction of prognosis in patients with PDAC before surgery.

OBJECTIVE: The standard treatment for ampullary tumors is pancreaticoduodenectomy. However, minimally invasive procedures such as endoscopic papillectomy (EP) and transduodenal ampullectomy (TDA) have recently gained popularity. Therefore, we aimed to evaluate the effectiveness of these minimally invasive procedures for ampullary tumors. METHODS: We conducted a retrospective study of 42 patients who underwent either EP or TDA for ampullary tumors between June 2011 and November 2020. RESULTS: We found that in patients with significantly larger tumors, TDA was often selected. Patients who underwent EP had significantly shorter hospital stays. No significant differences were observed regarding procedural accidents, tumor size, and recurrence. CONCLUSION: No differences were observed regarding the treatment outcomes of EP and TDA except hospital stay. EP is less invasive and can be the initial choice of procedure. TDA is performed when EP is not technically feasible. No significant relationship was noted between tumor size and recurrence, and careful observation of the patient's postoperative course is required.

OBJECTIVE: The concept of early chronic pancreatitis (ECP) and its diagnostic criteria were first proposed by Japan, using endoscopic ultrasonography (EUS) findings for diagnosis. However, these findings have not been supported by pathological findings. We aimed to examine the association between the EUS and pathological findings of the same area of the pancreas. METHODS: In 12 patients who underwent pancreaticoduodenectomy for distal bile duct cancer without accompanying pancreatitis, a comparative analysis between preoperative EUS and pathological findings was performed. The part of the pancreas adjoining the portal vein was evaluated. RESULTS: In 7 cases, abnormal EUS findings included in the diagnostic criteria for ECP were seen; the correlation of the accuracy of lobularity seen on EUS compared with the pathological findings of the pancreatic parenchyma (inflammatory cell infiltration, atrophy of acinar cells, and fibrosis) was high (83.3%-91.7%). Pancreatic duct findings revealed that the accuracy of the hyperechoic margin of the pancreatic duct on EUS compared with pathological findings (wall thickness of pancreatic duct) was high (83.3%). CONCLUSIONS: Endoscopic ultrasonography findings for ECP, according to Japan's 2019 revised criteria, lobularity, and the hyperechoic margin of the pancreatic duct may highly correspond to the pathological findings of chronic inflammation.

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.

We report a rare case of a large Brunner's gland hyperplasia (BGH) with severe anemia. A 33-year-old woman was transferred to our hospital with anemia and a duodenal mass. She had a 2-week history of melena and mild shortness of breath. Her hemoglobin level was 4.9 g/dl, and she required a blood transfusion. Abdominal computed tomography revealed a 7 cm tumor in the descending duodenum, and duodenoscopy revealed a polyp-like tumor with an ulcer at the duodenal bulb. We decided to perform surgery to prevent further bleeding. Intraoperatively, the tumor stalk was located at the anterior wall of the duodenal bulb; the ampulla was not involved, and we resected the tumor with the wall of the duodenal bulb. The resected tumor measured 7.0 × 4.0 × 2.3 cm, and pathologically, the tumor consisted of proliferated Brunner's glands in a small amount of fibrous stroma. The histological diagnosis was BGH with no malignancy. Most cases of BGH are benign and asymptomatic; however, it is important to be aware that some patients have severe anemia, gastrointestinal obstruction, or malignant potential.

Leiomyosarcoma of the inferior vena cava is a rare malignant tumor originating from smooth muscle cells of the vascular media. Its preoperative diagnosis by conventional noninvasive examinations such as abdominal ultrasonography, X-ray computed tomography, and magnetic resonance imaging, may be difficult because of their nonspecific findings. We present the case of a 72-year-old woman with leiomyosarcoma of the inferior vena cava diagnosed by intravascular ultrasonography.

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.