Circulating cell-free DNA methylation patterns as non-invasive biomarkers to monitor colorectal cancer treatment efficacy without referencing primary site mutation profiles.

This study investigates methylation patterns in circulating cell-free DNA (ccfDNA) for their potential role in colorectal cancer (CRC) detection and the monitoring of treatment response. Through methylation microarrays and quantitative PCR assays, we analyzed 440 samples from The Cancer Genome Atlas (TCGA) and an additional 949 CRC samples. We detected partial or extensive methylation in over 85% of cases within three biomarkers: EFEMP1, SFRP2, and UNC5C. A methylation score for at least one of the six candidate regions within these genes' promoters was present in over 95% of CRC cases, suggesting a viable detection method. In evaluating ccfDNA from 97 CRC patients and 62 control subjects, a difference in methylation and recovery signatures was observed. The combined score, integrating both methylation and recovery metrics, showed high diagnostic accuracy, evidenced by an area under the ROC curve of 0.90 (95% CI = 0.86 to 0.94). While correlating with tumor burden, this score gave early insight into disease progression in a small patient cohort. Our results suggest that DNA methylation in ccfDNA could serve as a sensitive biomarker for CRC, offering a less invasive and potentially more cost-effective approach to augment existing cancer detection and monitoring modalities, possibly supporting comprehensive genetic mutation profiling.

Long-term activation of anti-tumor immunity in pancreatic cancer by a p53-expressing telomerase-specific oncolytic adenovirus.

BACKGROUND: Pancreatic cancer is an aggressive, immunologically "cold" tumor. Oncolytic virotherapy is a promising treatment to overcome this problem. We developed a telomerase-specific oncolytic adenovirus armed with p53 gene (OBP-702). METHODS: We investigated the efficacy of OBP-702 for pancreatic cancer, focusing on its long-term effects via long-lived memory CD8 + T cells including tissue-resident memory T cells (TRMs) and effector memory T cells (TEMs) differentiated from effector memory precursor cells (TEMps). RESULTS: First, in vitro, OBP-702 significantly induced adenosine triphosphate (ATP), which is important for memory T cell establishment. Next, in vivo, OBP-702 local treatment to murine pancreatic PAN02 tumors increased TEMps via ATP induction from tumors and IL-15Rα induction from macrophages, leading to TRM and TEM induction. Activation of these memory T cells by OBP-702 was also maintained in combination with gemcitabine+nab-paclitaxel (GN) in a PAN02 bilateral tumor model, and GN + OBP-702 showed significant anti-tumor effects and increased TRMs in OBP-702-uninjected tumors. Finally, in a neoadjuvant model, in which PAN02 cells were re-inoculated after resection of treated-PAN02 tumors, GN + OBP-702 provided long-term anti-tumor effects even after tumor resection. CONCLUSION: OBP-702 can be a long-term immunostimulant with sustained anti-tumor effects on immunologically cold pancreatic cancer.

Robotic Pancreatoduodenectomy in Portal Annular Pancreas Using a Hanging Maneuver with Indocyanine Green Fluorescence Imaging.

BACKGROUND: Sufficient knowledge and surgical management of portal annular pancreas (PAP) are essential for pancreatic surgery. As PAP is a relatively rare pancreatic anomaly, few studies have described surgical techniques for patients with PAP undergoing robotic pancreatoduodenectomy (RPD). PATIENTS AND METHODS: An 82-year-old female patient who underwent RPD presented with distal cholangiocarcinoma and type III PAP (the fusion of the uncinate process with the anteportal main pancreatic duct). After the Kocher maneuver and stomach transection, the pancreas was transected into the neck of the anteportal portion. The retroportal portion was dissected, encircled with hanging tape, and compressed. Blood supply from the mesenteric vessels was confirmed using indocyanine green (ICG) fluorescence imaging. Subsequently, the retroportal portion was stapled. CONCLUSIONS: This study demonstrates a unique surgical technique for type III PAP using the hanging maneuver with ICG fluorescence imaging. Surgeons should decide on the surgical strategy on the basis of the fusion and ductal anatomy of the pancreas.

Genomically Stable Gastric Cancer Characterized by Hypomethylation in Wnt Signal Cascade.

INTRODUCTION: Gastric cancer is divided into four subtypes by their molecular features linked with genetic alterations, e.g., Epstein-Barr virus (EBV), microsatellite instability-high (MSI-high), chromosomal instability (CIN), and genomically stable (GS), called as TCGA classification. In this study, we tried to clarify the epigenetic features of the four GC subtypes according to aberrant methylation status in 23 loci. METHODS: A total of 98 gastric cancers and their normal gastric mucosa samples were included in this study. We divided gastric cancers into TCGA subtypes which were determined in line with MSI-high, EBV, CIN, to GS by their molecular features. The 13 loci of polymorphic microsatellite sequences were used to determine loss of heterogeneity for the detection of CIN. The MSI status was determined by three mononucleotide repeat markers. Infection of EBV was determined by recovering EBV BNRF1 sequence from genomic DNA collected from gastric cancers. Methylation status of 23 loci was investigated by the combined bisulfite restriction analysis. Status of other findings, e.g., KRAS mutations, HER2 expression status, and infection of helicobacter pylori were confirmed. RESULTS: Gastric cancers were divided into MSI (13%), EBV (7%), CIN (53%), and GS (27%). By histological classification, poorly differentiated adenocarcinoma was more in tumors categorized in MSI-high, and GS and signet-ring cell carcinoma (sig) were more in GS. Among the 23 loci investigated their methylation status, 18 loci were significantly hypermethylated in caner tissues. An unsupervised clustering divided gastric cancers into two clusters and revealed that most GS tumors clustered together in a cluster that exhibited lower methylation levels, distinct from the other subtypes. The inter-variable clustering revealed that a cluster contained the three loci (SFRP2-region 1/2 and APC) belonging to the Wnt signal cascade (Wnt-associated loci). The mean methylation score of Wnt-associated loci was the lowest in GS tumors (MSI-high: 2.7 [95% confidence interval, 2.3-2.9]; EBV: 2.1 [1.2-3.1]; CIN: 2.4 [2.2-2.7]; GS: 1.3 [0.8-0.7]). In contrast, the mean methylation score of the other 15 loci was significantly higher in MSI-high, while that in GS was as same as that in EBV or CIN (MSI-high: 10.4 [8.3-12.4]; EBV: 5.7 [1.7-9.7]; CIN: 4.4 [3.6-5.1]; GS: 3.4 [2.2-4.6]). Additionally, the lower methylation score of Wnt-associated loci was observed only in sig tumors. CONCLUSIONS: GS subtype tumors have the potential to possess distinct signatures in DNA hypomethylation profiles in Wnt signaling pathway, especially in sig.

Innovative suture technique for robotic hepaticojejunostomy: double-layer interrupted sutures.

PURPOSE: Biliary reconstruction remains a technically demanding and complicated procedure in minimally invasive hepatopancreatobiliary surgeries. No optimal hepaticojejunostomy (HJ) technique has been demonstrated to be superior for preventing biliary complications. This study aimed to investigate the feasibility of our unique technique of posterior double-layer interrupted sutures in robotic HJ. METHODS: We performed a retrospective analysis of a prospectively collected database. Forty-two patients who underwent robotic pancreatoduodenectomy using this technique between September 2020 and November 2022 at our center were reviewed. In the posterior double-layer interrupted technique, sutures were placed to bite the bile duct, posterior seromuscular layer of the jejunum, and full thickness of the jejunum. RESULTS: The median operative time was 410 (interquartile range [IQR], 388-478) min, and the median HJ time was 30 (IQR, 28-39) min. The median bile duct diameter was 7 (IQR, 6-10) mm. Of the 42 patients, one patient (2.4%) had grade B bile leakage. During the median follow-up of 12.6 months, one patient (2.4%) with bile leakage developed anastomotic stenosis. Perioperative mortality was not observed. A surgical video showing the posterior double-layer interrupted sutures in the robotic HJ is included. CONCLUSIONS: Posterior double-layer interrupted sutures in robotic HJ provided a simple and feasible method for biliary reconstruction with a low risk of biliary complications.

Regulatory T cells induce a suppressive immune milieu and promote lymph node metastasis in intrahepatic cholangiocarcinoma.

BACKGROUND: Emerging evidence indicates that immunogenicity plays an important role in intrahepatic cholangiocarcinoma (ICC). Herein, we systematically evaluated the clinical relevance of immunogenicity in ICC. METHODS: Highly immunogenic ICCs identified in the public dataset and the Cancer Immunome Atlas (TCIA) were assessed to determine the prognostic impact of immunogenicity in ICC and key components after curative resection. We also investigated the clinical relevance of the immune milieu in ICC. RESULTS: Using the Gene Expression Omnibus dataset 89749 and TCIA, we identified CD8+/forkhead box P3 (FoxP3)+ tumour-infiltrating lymphocytes (TILs), T-cell immunoglobulin and mucin domain 3 (TIM-3) and human leukocyte antigen-A (HLA-A) in highly immunogenic ICCs. Immunohistochemical analysis of the in-house cohort showed that intratumoral FoxP3+ TILs correlated with CD8+ TILs (P = 0.045, Fisher's exact test) and that high FoxP3+/CD8+ ratio (FCR) was an important marker for poor survival (P < 0.001, log-rank test). Furthermore, the FCR was higher in tumour-free lymph nodes in ICCs with lymph node metastases than in those without lymph node metastases (P = 0.003, Mann-Whitney U test). CONCLUSIONS: FCR should be considered an important biomarker that represents the immune environment of ICC based on its potentially important role in tumour progression, especially lymph node metastasis.

Optimal surveillance of intraductal papillary mucinous neoplasms of the pancreas focusing on remnant pancreas recurrence after surgical resection.

BACKGROUND: The international consensus guidelines for intraductal papillary mucinous neoplasm of the pancreas (IPMN) presented clinical features as indications for surgery. Whereas surveillance for recurrence, including de novo lesions, is essential, optimal surveillance protocols have not been established. AIM AND METHODS: This study aimed to assess the clinical features of recurrence at the remnant pancreas (Rem-Panc) and extra-pancreas (Ex-Panc) after surgery for IPMN. Ninety-one patients of IPMN that underwent detailed preoperative assessment and pancreatectomy were retrospectively analyzed, focusing especially on the type of recurrence. RESULTS: The IPMNs were finally diagnosed as low-grade dysplasia (LDA, n = 42), high-grade dysplasia (HAD, n = 19), and invasive carcinoma (IPMC, n = 30). Recurrence was observed in 26 patients (29%), of which recurrence was seen at Rem-Panc in 19 patients (21%) and Ex-Panc in 7 patients (8%). The frequency of Rem-Panc recurrence was 10% in LDA, 21% in HDA, and 37% in IPMC. On the other hand, Ex-Panc recurrence was observed only in IPMC (23%). Ex-Panc recurrence showed shorter median recurrence-free survival (RFS) and overall survival (OS) than Rem-Panc recurrence (median RFS 8 months vs. 35 months, p < 0.001; median OS 25 months vs. 72 months, p < 0.001). Regarding treatment for Rem-Panc recurrence, repeat pancreatectomy resulted in better OS than no repeat pancreatectomy (MST 36 months vs. 15.5 months, p = 0.033). On multivariate analysis, main duct stenosis or disruption as a preoperative feature (hazard ratio [HR] 10.6, p = 0.002) and positive surgical margin (HR 4.4, p = 0.018) were identified as risk factors for Rem-Panc recurrence. CONCLUSIONS: The risk factors for Rem-Panc and Ex-Panc recurrence differ. Therefore, optimal surveillance on these features is desirable to ensure that repeat pancreatectomy for Rem-Panc recurrence can be an appropriate surgical intervention.

Feasibility of local therapy for recurrent pancreatic cancer.

BACKGROUND: Despite advances in perioperative management, recurrence after curative pancreatectomy is a critical issue in the treatment of pancreatic ductal adenocarcinoma (PDAC). The significance of local therapy for recurrent PDAC remains unclear. METHODS: We reviewed the medical records of patients with PDAC who underwent curative resection at our institution between January 2009 and December 2019. We examined the patterns of relapse and assessed the clinical outcomes of patients with recurrence who underwent local therapy, including surgical resection, radiotherapy, and radiofrequency ablation. RESULTS: A total of 246 patients with PDAC who underwent R0 or R1 resection were included in this study. The 3-year overall survival (OS) rate was 39.8%, and the 1-year recurrence-free survival rate was 51.2% for the entire population. Recurrence was observed in 172/246 (69.9%) patients, including multiple site recurrences in 50, liver metastasis in 41, locoregional recurrence in 34, and peritoneal dissemination in 27. Of the 172 patients, treatment was administered in 137 (79.7%), and 16 received local therapy, including surgical resection (n = 13), radiotherapy (n = 5), and RFA (n = 1). PS-matched analysis revealed that patients with recurrence who were treated with chemotherapy combined with local therapy showed better post-recurrence survival rates than those treated with chemotherapy alone (P = 0.016). Detailed clinical courses of these patients are presented in the main manuscript. CONCLUSIONS: Our results suggest that a multimodal approach may improve the clinical outcomes of patients with recurrent PDAC.

Robotic Spleen-Preserving Distal Pancreatectomy with Preservation of Splenic Vessels Using the Gastrohepatic Ligament Approach: The Superior Window Approach in the Kimura Technique.

Minimally invasive spleen-preserving distal pancreatectomy (SPDP) is technically challenging, and only a few reports have described surgical approaches for minimally invasive SPDP. This report demonstrates our novel gastrohepatic ligament approach in robotic SPDP with preservation of the splenic vessels (the superior window approach in the Kimura technique). Our gastrohepatic ligament approach for robotic SPDP included four steps. First, the gastrohepatic ligament was divided extensively, and the pancreas was confirmed (step 1). In this step, we did not lift the stomach, nor did we divide the gastrocolic ligament. Next, the superior and inferior borders of the pancreas were dissected, and the tunneling of the pancreas on the superior mesenteric vein was performed (step 2). Following the division of the pancreas (step 3), the pancreatic body and tail were dissected from the medial to the lateral side with preservation of the splenic vessels (step 4). Using this approach, the pancreas can be directly accessed via the gastrohepatic ligament route and dissected without division of the gastrocolic ligament or retraction of the stomach. The present approach for robotic SPDP preserves splenic vessels, facilitating easy access to the pancreas with minimal dissection, and may be optional in selected patients, including those with low body mass index.

Technique of vessel-skeletonized parenchyma-sparing hepatectomy for the oncological treatment of bilobar colorectal liver metastases.

BACKGROUND: To aid in the oncological management of multiple bilobar colorectal liver metastases (CRLMs), we describe a new surgical procedure, VEssel-Skeletonized PArenchyma-sparing Hepatectomy (VESPAH). STUDY DESIGN: Of 152 patients with CRLMs treated with hepatectomy, 33 patients had multiple bilobar liver metastases (≥8 liver metastases); their surgical procedures and clinical outcomes were retrospectively summarized and compared between those who underwent VESPAH and those who underwent major hepatectomy (Major Hx). RESULTS: Of the 33 patients, 20 patients were resected by VESPAH (the VESPAH group) and 13 patients by major hepatectomy (Major Hx group). The median number of CRLMs was 13 (range, 8-53) in the VESPAH group and 10 (range, 8-41) in the Major Hx group (P=0.511). No operative mortality nor severe morbidity was observed in either group. The VESPAH group showed earlier recovery of remnant liver function after surgery than the Major Hx group; the incidence of grade B/C post hepatectomy liver failure was 5% in the VESPAH group and 38% in the Major Hx group, P=0.048). Intrahepatic tumor recurrence was confirmed in 14 (70%) and 7 (54%) patients in the VESPAH and Major Hx groups, respectively (P=0.416). There was no significant difference in median overall survival (OS) after hepatectomy between the two groups; the median OS was 47 months in the VESPAH group and 33 months in the Major Hx group (P=0.481). The VESPAH group showed the higher induction rate of adjuvant chemotherapy within 2 months after surgery (P=0.002) and total number of repeat hepatectomy for intrahepatic recurrence (P=0.060) than the Major Hx group. CONCLUSIONS: VESPAH enables us to clear surgical navigation by hepatic vessel skeletonization and may enhance patient tolerability of not only adjuvant chemotherapy but also repeat hepatectomies during the patients' lifetimes.

Neonatal hemochromatosis with εγδß-thalassemia: a case report and analysis of serum iron regulators.

BACKGROUND: Neonatal hemochromatosis causes acute liver failure during the neonatal period, mostly due to gestational alloimmune liver disease (GALD). Thalassemia causes hemolytic anemia and ineffective erythropoiesis due to mutations in the globin gene. Although neonatal hemochromatosis and thalassemia have completely different causes, the coexistence of these diseases can synergistically exacerbate iron overload. We report that a newborn with εγδß-thalassemia developed neonatal hemochromatosis, which did not respond to iron chelators and rapidly worsened, requiring living-donor liver transplantation. CASE PRESENTATION: A 1-day-old Japanese boy with hemolytic anemia and targeted red blood cells was diagnosed with εγδß-thalassemia by genetic testing, and required frequent red blood cell transfusions. At 2 months after birth, exacerbation of jaundice, grayish-white stool, and high serum ferritin levels were observed, and liver biopsy showed iron deposition in hepatocytes and Kupffer cells. Magnetic resonance imaging scans showed findings suggestive of iron deposits in the liver, spleen, pancreas, and bone marrow. The total amount of red blood cell transfusions administered did not meet the criteria for post-transfusion iron overload. Administration of an iron-chelating agent was initiated, but iron overload rapidly progressed to liver failure without improvement in jaundice and liver damage. He underwent living-donor liver transplantation from his mother, after which iron overload disappeared, and no recurrence of iron overload was observed. Immunohistochemical staining for C5b-9 in the liver was positive. Serum hepcidin levels were low and serum growth differentiation factor-15 levels were high prior to living-donor liver transplantation. CONCLUSIONS: We reported that an infant with εγδß-thalassemia developed NH due to GALD, and that coexistence of ineffective erythropoiesis in addition to erythrocyte transfusions may have exacerbated iron overload. Low serum hepcidin levels, in this case, might have been caused by decreased hepcidin production arising from fetal liver damage due to neonatal hemochromatosis and increased hepcidin-inhibiting hematopoietic mediators due to the ineffective hematopoiesis observed in thalassemia.

Multiple Hepatolithiasis Following Hepaticojejunostomy Successfully Treated with Left Hemihepatectomy and Double Hepaticojejunostomy Reconstruction.

Surgical intervention for hepatolithiasis following hepaticojejunostomy (HJ) has rarely been reported. Herein, we present a case of post-HJ multiple hepatolithiasis treated with left hemihepatectomy with double HJ reconstruction. A 72-year-old woman who had undergone HJ for iatrogenic bile duct injury developed repeated cholangitis due to complicated hepatolithiasis accompanied by an atrophied left hepatic lobe and HJ stricture. Since endoscopic intervention was unsuccessful, the patient underwent left hemihepatectomy with HJ re-anastomoses of the common hepatic duct and left hepatic duct (double HJ technique). The double HJ technique with hepatectomy can be a useful option for treating complicated hepatolithiasis following HJ.

Usefulness of Middle Colic Artery Transposition Technique for Hepatic Arterial Reconstruction in Conversion Surgery for an Initially Unresectable, Locally Advanced Pancreatic Cancer.

The outcomes of pancreatectomy with resection and reconstruction of the involved arteries for locally advanced pancreatic cancer following chemotherapy have improved in recent years. In pancreatic head cancers in which there is contact with the common and proper hepatic arteries, margin-negative resection requires pancreati-coduodenectomy, with the resection of these arteries and the restoration of hepatic arterial flow. Here, we describe a middle colic artery transposition technique in hepatic arterial reconstruction during pancreatoduo-denectomy for an initially unresectable locally advanced pancreatic cancer. This technique was effective and may provide a new option for hepatic artery reconstruction in such cases.

Hemobilia after bile duct resection: perforation of pseudoaneurysm into intra-pancreatic remnant bile duct: a case report.

BACKGROUND: Hemobilia occurs mainly due to iatrogenic factors such as impairment of the right hepatic or cystic artery, and/or common bile duct in hepatobiliary-pancreatic surgery. However, little or no cases with hemobilia from the intra-pancreatic remnant bile duct after bile duct resection (BDR) has been reported. Here, we report a case of massive hemobilia due to the perforation of psuedoaneurysm of the gastroduodenal artery (GDA) to the intra-pancreatic remnant bile duct after hepatectomy with BDR. CASE PRESENTATION: A 68-year-old male underwent extended right hepatectomy with BDR for gallbladder carcinoma. He presented with upper gastrointestinal bleeding 2 months after the initial surgery. Upper endoscopy identified a blood clot from the ampulla of Vater and simultaneous endoscopic balloon tamponade contributed to temporary hemostasis. Abdominal CT and angiography revealed a perforation of the psuedoaneurysm of the GDA to the intra-pancreatic remnant bile duct resulting in massive hemobilia. Subsequent selective embolization of the pseudoaneurysm with micro-coils could achieve complete hemostasis. He survived without any recurrence of cancer and bleeding. CONCLUSION: Hemobilia could occur in a patient with BDR due to perforation of the pseudoaneurysm derived from the GDA to the intra-pancreatic remnant bile duct. Endoscopic balloon tamponade was useful for a temporal hemostasis and a subsequent radiologic interventional approach.

Detection of circulating microRNAs with Ago2 complexes to monitor the tumor dynamics of colorectal cancer patients during chemotherapy.

Because of the different forms of circulating miRNAs in plasma, Argonaute2 (Ago2)-miRNAs and extracellular vesicles (EV-miRNAs), we examined the two forms of extracellular miRNAs in vitro and developed a unique methodology to detect circulating Ago2-miRNAs in small volumes of plasma. We demonstrated that Ago2-miR-21 could be released into the extracellular fluid by active export from viable cancer cells and cytolysis in vitro. As miR-21 and miR-200c were abundantly expressed in both metastatic liver sites and primary lesions, we evaluated Ago2-miR-21 as a candidate biomarker of both active export and cytolysis while Ago2-miR-200c as a biomarker of cytolysis in plasma obtained from colorectal cancer (CRC) patients before treatment and in a series of plasma obtained from CRC patients with liver metastasis who received systemic chemotherapy. The measurement of Ago2-miR-21 allowed us to distinguish CRC patients from subjects without CRC. The trend in ΔCt values for Ago2-miR-21 and -200c during chemotherapy could predict tumor response to ongoing treatment. Thus, capturing circulating Ago2-miRNAs from active export can screen patients with tumor burdens, while capturing them from passive release by cytolysis can monitor tumor dynamics during chemotherapy treatment.

Optimal bearing gap of a multiarc radial bearing in a hydrodynamically levitated centrifugal blood pump for the reduction of hemolysis.

We have developed a hydrodynamically levitated centrifugal pump as a bridge-to-decision device. The purpose of the present study is to determine the optimal bearing gap of a multiarc radial bearing in the developed blood pump for the reduction of hemolysis. We prepared eight pump models having bearing gaps of 20, 30, 40, 80, 90, 100, 180, and 250 µm. The driving conditions were set to a pressure head of 200 mm Hg and a flow rate of 4 L/min. First, the orbital radius of the impeller was measured for the evaluation of the impeller stability. Second, the hemolytic property was evaluated in an in vitro hemolysis test. As a result, the orbital radius was not greater than 15 µm when the bearing gap was between 20 and 100 µm. The relative normalized index of hemolysis (NIH) ratios in comparison with BPX-80 were 37.67 (gap: 20 µm), 0.95 (gap: 30 µm), 0.96 (gap: 40 µm), 0.82 (gap: 80 µm), 0.77 (gap: 90 µm), 0.92 (gap: 100 µm), 2.76 (gap: 180 µm), and 2.78 (gap: 250 µm). The hemolysis tended to increase at bearing gaps of greater than 100 µm due to impeller instability. When the bearing gap decreased from 30 to 20 µm, the relative NIH ratios increased significantly from 0.95 to 37.67 times (P < 0.01) due to high shear stress. We confirmed that the optimal bearing gap was determined between 30 and 100 µm in the developed blood pump for the reduction of hemolysis.

Role of robotic surgery as an element of Enhanced Recovery After Surgery protocol in patients undergoing pancreatoduodenectomy.

BACKGROUND: Although the current trend in pancreatoduodenectomy (PD) has shifted from open surgery to minimally invasive surgery (MIS), evidence on the role of MIS as an element of Enhanced Recovery After Surgery (ERAS) in PD is limited. This study aimed to investigate the effect of robotic surgery using the ERAS protocol on the outcomes of patients undergoing PD. METHODS: This retrospective study included 252 patients who underwent open PD (OPD) or robotic PD (RPD) managed using the ERAS protocol between January 2017 and March 2023. Outcomes stratified by the surgical approach were compared. Multivariable analyses were performed to evaluate the effect of ERAS items, including robotic surgery, on outcomes after PD. RESULTS: Of 252 patients, 202 (80.2%) underwent OPD, and 50 (19.2%) underwent RPD. Multivariable analyses demonstrated that perioperative management center support (odds ratio [OR], 2.85; 95% CI, 1.14-7.72; P = .025), robotic surgery (OR, 6.40; 95% CI, 1.94-26.1; P = .002), early solid intake (OR, 2.84; 95% CI, 1.46-5.63; P = .002), and early drain removal (OR, 3.77; 95% CI, 2.04-7.06; P < .001) were significant ERAS items related to early discharge after PD. CONCLUSION: Our study demonstrated that employing the ERAS protocol for OPD and RPD is feasible and safe. Moreover, our results suggested the role of robotic surgery as an element of the ERAS protocol for PD. A combination of ERAS protocols and MIS may be safe and feasible for accelerating postoperative recovery after PD.

BRAF-mutant microsatellite-stable rectal cancer with acquired KRAS mutation leading to drug resistance in liver metastasis.

BRAF-mutant microsatellite-stable colorectal cancer (CRC), metastasized to distant sites, is associated with a poor prognosis. However, the BEACON CRC regimen, comprising a BRAF inhibitor, MEK inhibitor, and anti-EGFR antibody, offered a prolonged prognosis. Nonetheless, resistance to this regimen may occur, as observed in our reported case of CRC, where a KRAS mutation was identified in addition to the BRAF V600E mutation. Here, we present a case of 74-year-old woman with rectal cancer (pT4bN1bM0 Stage IIIc) harboring the BRAF V600E mutation. After resection of the primary tumor and during adjuvant chemotherapy using CAPOX (capecitabine and oxaliplatin), liver and lung metastases became apparent, and a companion diagnosis test revealed the presence of a BRAF V600E mutation. The new lesions were deemed resistant to the CAPOX regimen, and we decided to introduce encorafenib and cetuximab. After resection of liver metastases, encorafenib and cetuximab were reintroduced, but a new lesion appeared in hepatic S7, indicating resistance to the encorafenib and cetuximab regimen. The resistant liver metastasis was subsequently resected. To elucidate the resistance mechanism, we conducted a comprehensive analysis using the FoundationOne CDx cancer gene panel test, revealing the presence of a KRAS Q61H mutation alongside the BRAF V600E mutation. Subsequent liquid biopsy after liver recurrence confirmed the persistence of the KRAS Q61H mutation. Our results highlight the significance of cancer genome profiling tests (CGP tests) and liquid biopsies in guiding treatment strategies for BRAF-mutant colorectal cancer. Therefore, CGP testing offers valuable information for treatment, even if it does not lead to new drug administrations.

Optimal design of the hydrodynamic multi-arc bearing in a centrifugal blood pump for the improvement of bearing stiffness and hemolysis level.

The purpose of the present study is to establish an optimal design of the multi-arc hydrodynamic bearing in a centrifugal blood pump for the improvement of bearing stiffness and hemolysis level. The multi-arc bearing was designed to fulfill the required specifications: (i) ensuring the uniform bearing stiffness for various bearing angles; (ii) ensuring a higher bearing stiffness than the centrifugal force to prevent impeller whirl; and (iii) adjusting the bearing clearance as much as possible to reduce hemolysis. First, a numerical analysis was performed to optimize three design parameters of the multi-arc bearing: number of arcs N, bearing clearance C, and groove depth H. To validate the accuracy of the numerical analysis, the impeller trajectories for six pump models were measured. Finally, an in vitro hemolysis test was conducted to evaluate the hemolytic property of the multi-arc bearing. As a result of the numerical analysis, the optimal parameter combination was determined as follows: N=4, C=100 µm, and H ≥ 100 µm. In the measurements of the impeller trajectory, the optimal parameter combination was found to be as follows: N=4, C=90 µm, and H=100 µm. This result demonstrated the high reliability of the numerical analysis. In the hemolysis test, the parameter combination that achieved the smallest hemolysis was obtained as follows: N=4, C=90 µm, and H=100 µm. In conclusion, the multi-arc bearing could be optimized for the improvement of bearing stiffness and hemolysis level.