Preoperative level of serum transthyretin as a novel biomarker predicting survival in resected pancreatic ductal adenocarcinoma with neoadjuvant therapy.

BACKGROUND: Systemic inflammation and altered metabolism are essential hallmarks of cancer. We hypothesized that the rapid turnover protein transthyretin (TTR) (half-life: 2-3 days), compared with the conventional marker albumin (21 days), better reflects the inflammatory/metabolic dynamics of pancreatic ductal adenocarcinoma (PDAC) after neoadjuvant therapy (NAT) and is a useful prognostic marker. METHODS: Serum TTR and albumin levels were measured in 104 consecutive post-NAT PDAC patients before curative resection. The associations of preoperative TTR and albumin levels with overall survival (OS) after pancreatectomy were retrospectively analyzed. RESULTS: The mean (SD) TTR and albumin levels were 21.6 (6.4) mg/dL (normal range: ≥22.0 mg/dL) and 3.9 (0.55) g/dL. A low (<22.0 mg/dL) post-NAT TTR level was associated with an advanced tumor stage and higher CEA and CRP levels. Patients with low TTR levels showed significantly worse OS compared with normal levels (3-year OS 39 % vs. 54 %, P = 0.037), although albumin levels did not. We modified prognostic biomarkers of systemic inflammation/metabolism, such as GPS, PNI, and CONUT scores, using the serum TTR instead of albumin level and successfully showed that modified scores were better associated with OS compared with original scores using serum albumin level. CONCLUSIONS: Our data suggest that the TTR level is a promising prognostic biomarker for PDAC patients after NAT.

Robot-assisted approach using a laparoscopic articulating vessel-sealing device versus pure-robotic approach during distal pancreatectomy.

Robotic distal pancreatectomy (RDP) has emerged as a minimally invasive approach to left-sided pancreatic tumors. This study aimed to evaluate the efficacy of the robot-assisted approach (RAA) using a laparoscopic articulating vessel-sealing device (LAVSD) during RDP by comparing it with the pure-robotic approach (PRA). Among 62 patients who underwent RDP between April 2020 and December 2023 at Fujita Health University, 22 underwent RAA (the RAA group). In RAA, console surgeons mainly prepared the surgical fields, and assistant surgeons actively dissected the adipose and connective tissues using LAVSD. The surgical outcomes of these patients were compared with those of 40 consecutive patients who underwent RDP with PRA. In total, 28 males and 34 females with a median age of 71 years were analyzed. The console surgeon's prior experience of performing RDP was similar between the groups (RAA; median, 6 [range, 0-36], PRA; median, 5.5 [range, 0-34] cases). The operation time was significantly shorter in the TST group (median, 300.5 [range, 202-557] vs. 363.5 [range, 230-556] min, p = 0.015). Major complications (Clavien-Dindo ≥ grade 3a) occurred less frequently in the RAA group (4.6% vs. 25.0%, p = 0.028). Although the median postoperative hospital stay was slightly shorter in the RAA group (median, 12 [range, 8-38] vs. 14.5 [8-44] days, p = 0.095), no statistically significant difference was observed. Compared with PRA, RAA using LAVSD is found to be safe and feasible in introducing RDP for operators with little experience.

Task division by multiple console surgeons is beneficial for safe robotic pancreaticoduodenectomy implementation and education.

BACKGROUND: The optimal approach for the safe implementation and education of robotic pancreaticoduodenectomy (RPD) remains unclear. Prolonged operation time may cause surgeon fatigue and result in perioperative complications. To solve this issue, our department adopted task division by the console surgeon turnover between resection and reconstruction in 2022. METHODS: This study retrospectively investigated consecutive patients who underwent RPD from November 2009 (initial introduction of RPD) to December 2023. The analysis excluded patients who underwent concomitant resection of other organs. The cases performed by a single console surgeon (single approach) were compared with those performed by two or more console surgeons (multiple approach). RESULTS: This study analyzed 85 consecutive RPD cases, including 51 with the single approach and 34 with the multiple approach. The operation time was significantly shorter (832 vs. 618 min, p < 0.001), and the postoperative major complication was less frequent (45% vs. 12%, p = 0.003) in the multiple approach group, although less experienced surgeons performed the multiple approach (number of RPD experiences: 19 cases vs. 5 cases, p < 0.001). The console surgeon turnover between the resection and reconstruction resulted in a safe pancreatojejunostomy performed by the less experienced surgeon (number of pancreatic reconstruction experiences: 6.5 vs. 14 cases, p = 0.010). Surgeons who started RPD with a multiple approach observed a reduction in surgical time and a lower incidence of complications earlier than those who started with a single approach. CONCLUSION: Task division during the early introduction phase of RPD using the multiple approach demonstrated potential contributions to improved surgical outcomes and enhanced educational benefits.

Technical details of robotic pancreatojejunostomy using a modified Blumgart anastomosis: Thread manipulation using gauze and an assisted port.

BACKGROUNDS: Pancreatojejunostomy is a technically demanding procedure during robotic pancreaticoduodenectomy (RPD). Modified Blumgart anastomosis (mBA) is a common method for the pancreatojejunostomy; however, the technical details for robotic mBA are not well established. During RPD, we performed a mBA for the pancreatojejunostomy using thread manipulation with gauze and an additional assist port. METHODS: Patients who underwent robotic pancreatoduodenectomy at Fujita Health University from November 2009 to May 2023 were retrospectively investigated, and technical details for the robotic-modified Blumgart anastomosis were demonstrated. RESULTS: Among 78 patients who underwent RPD during the study period, 33 underwent robotic mBA. Postoperative pancreatic fistula (POPF) occurred in six patients (18%). None of the patients suffered POPF Grade C according to the international study group of pancreatic surgery definition. The anastomotic time for mBA was 80 min (54-125 min). CONCLUSION: Robotic mBA resulted in reasonable outcomes. We propose that mBA could be used as one of the standard methods for robotic pancreatojejunosotomy.

Challenge in optimizing robotic pancreaticoduodenectomy including nerve plexus hanging maneuver: a Japanese single center experience of 76 cases.

BACKGROUND: Robotic pancreaticoduodenectomy (RPD) is technically demanding, and 20-50 cases are required to surpass the learning curve. This study aimed to show our experience of 76 cases from the introduction of RPD and report the changes in surgical results owing to the accumulation of cases and optimization of surgical techniques. METHODS: A total of 76 patients who underwent RPD between November 2009 and May 2023 at the Fujita Health University Hospital were divided into three groups: competency (n = 23, Nov 2009-Mar 2020), proficiency (n = 31, Apr 2020-Jun 2022), and mastery (n = 22, Jul 2022-May 2023) phases. In the mastery phase, for the education of new surgeons and maintenance of surgical quality, optimization of the procedure, including hanging maneuver with or without stapling transection of the retropancreatic tissue was implemented. The surgical outcomes were compared between the groups. RESULTS: The mean operation time decreased over time despite of the participation of newly started operators in mastery phase [competency: 921.5 min (IQR 775-996 min) vs. proficiency: 802.8 min (IQR 715-887 min) vs. mastery: 609.2 min (IQR 514-699 min), p < 0.001]. Additionally, Clavien-Dindo ≥ grade IIIa complications decreased from 52.2% in competency phase to 35.5% and 9.1% in proficiency and mastery phases, respectively (p = 0.005). CONCLUSION: Operation time and major complications decreased along the learning curve from the introduction of RPD. In addition, optimization of the procedure, including hanging maneuver of the retropancreatic tissue seemed to be effective in reducing operation time and educating new RPD surgeons.

Robotic pancreatic tumor enucleation by the double bipolar technique using the da Vinci SP system: An initial case report with a technical detail.

Pancreatic tumor enucleation is a procedure that can preserve pancreatic function and is sometimes performed using a minimally invasive approach. Recently, a single-port robotic platform called da Vinci SP has been developed. However, the technical details of pancreatic tumor enucleation using da Vinci SP have not been reported to date. We report a male patient in his 70s who underwent robotic SP pancreatic tumor enucleation for a pancreatic neuroendocrine tumor. The dissection between the tumor and pancreatic parenchyma was performed using the double bipolar technique. The operative time was 139 min, and the estimated blood loss was 4 mL. The patient had an uneventful recovery and was discharged on the sixth day after the surgery. Robotic SP pancreatic tumor enucleation appears to be a feasible procedure with lower invasiveness and better cosmesis.

Risk Factors for Recurrence of Cholangitis After Pancreaticoduodenectomy and Comparison of Stents in Hepaticojejunostomy.

BACKGROUND: Postoperative cholangitis is a common complication of pancreaticoduodenectomy. Frequent cholangitis impairs patients' quality of life after pancreaticoduodenectomy. However, the risk factors for recurrence of cholangitis remain unclear. Hence, this retrospective study aimed to identify risk factors for recurrence of cholangitis after pancreaticoduodenectomy. METHODS: The medical records of patients who underwent pancreaticoduodenectomy between 2015 and 2019 in our institution were retrospectively reviewed. At least two episodes of cholangitis a year after pancreaticoduodenectomy were defined as 'recurrence of cholangitis' in the present study. Univariate and multivariate analyses were performed. RESULTS: The recurrence of cholangitis occurred in 40 of 207 patients (19.3%). Multivariate analysis revealed that internal stent (external, RR: 2.16, P = 0.026; none, RR: 4.76, P = 0.011), firm pancreas (RR: 2.61, P = 0.021), constipation (RR: 3.49, P = 0.008), and postoperative total bilirubin>1.7 mg/dL (RR: 2.94, P = 0.006) were risk factors of recurrence of cholangitis. Among patients with internal stents (n = 54), those with remnant stents beyond 5 months had more frequent recurrence of cholangitis (≥5 months, 75%; <5 months, 30%). CONCLUSIONS: Internal stents, firm pancreas, constipation, and postoperative high bilirubin levels are risk factors for cholangitis recurrence after pancreaticoduodenectomy. In addition, the long-term implantation of internal stents may trigger cholangitis recurrence.

Minimally Invasive Anatomic Liver Resection for Hepatocellular Carcinoma Using the Extrahepatic Glissonian Approach: Surgical Techniques and Comparison of Outcomes with the Open Approach and between the Laparoscopic and Robotic Approaches.

Surgical techniques and outcomes of minimally invasive anatomic liver resection (AR) using the extrahepatic Glissonian approach for hepatocellular carcinoma (HCC) are undefined. In 327 HCC cases undergoing 185 open (OAR) and 142 minimally invasive (MIAR; 102 laparoscopic and 40 robotic) ARs, perioperative and long-term outcomes were compared between the approaches, using propensity score matching. After matching (91:91), compared to OAR, MIAR was significantly associated with longer operative time (643 vs. 579 min, p = 0.028); less blood loss (274 vs. 955 g, p < 0.0001); a lower transfusion rate (17.6% vs. 47.3%, p < 0.0001); lower rates of major 90-day morbidity (4.4% vs. 20.9%, p = 0.0008), bile leak or collection (1.1% vs. 11.0%, p = 0.005), and 90-day mortality (0% vs. 4.4%, p = 0.043); and shorter hospital stay (15 vs. 29 days, p < 0.0001). On the other hand, laparoscopic and robotic AR cohorts after matching (31:31) had comparable perioperative outcomes. Overall and recurrence-free survivals after AR for newly developed HCC were comparable between OAR and MIAR, with potentially improved survivals in MIAR. The survivals were comparable between laparoscopic and robotic AR. MIAR was technically standardized using the extrahepatic Glissonian approach. MIAR was safe, feasible, and oncologically acceptable and would be the first choice of AR in selected HCC patients.

Robotic instruments outside the surgical field can cause problems: A case of critical bleeding during robotic distal pancreatectomy.

Robotic surgery has technical advantages including high optical magnification and articulation of forceps. However, the surgical field tends to be narrow due to the high magnification, and the forceps have no tactile sensation. A case of severe intraoperative bleeding from the splenic artery during robotic distal pancreatectomy is presented, with a video. A man in his 80s with a cystic tumor located at the pancreatic tail underwent robotic distal pancreatectomy. During mobilization of the pancreatic tail by an inferior approach, the root of the splenic artery was injured by the joints of the robotic instruments located outside the surgical field and the bleeding became uncontrollable under the robotic operation. It is important to always be aware of what the forceps are in contact with outside the surgical field. While dissecting the left subdiaphragmatic area in robotic distal pancreatectomy, the root area of splenic artery tends to be outside the surgical field. More attention should be paid to the positional relationship between the forceps trajectory and the major blood vessels by checking the surgical field from a distant view on a regular basis.

Use of a short cartridge stapler is beneficial in pancreatic transection at the neck during laparoscopic distal pancreatectomy.

Stapling is the standard method for pancreatic transection during laparoscopic distal pancreatectomy. Although most surgeons use a 60 mm cartridge stapler, space limitations created by laparoscopic surgery make the instrument difficult to handle, especially during pancreatic transection at the neck. Therefore, we currently use a 45 mm cartridge stapler for laparoscopic pancreatic transection at the neck. Between October 2019 and December 2020, we performed pancreatic transection using a 45 mm cartridge stapler in 27 patients. Fifteen patients experienced biochemical leakage, but no patients developed clinically relevant pancreatic fistula. The compactness of the 45 mm cartridge has several benefits: (1) less space is required for flexing, opening, and closing the device; (2) it enables easy insertion of the lower jaw behind the pancreas, even if the dissected space behind the pancreas is narrow; (3) less obstruction of the surgeons' view prevents accidental injury to the surrounding tissues and vessels. These benefits may enable safe pancreatic transection.

Standardization of laparoscopic anatomic liver resection of segment 2 by the Glissonean approach.

BACKGROUND: Anatomic liver resection (ALR) has been established to eliminate the tumor-bearing hepatic region with preservation of the remnant liver volume for liver malignancies. Recently, laparoscopic ALR has been widely applied; however, there are few reports on laparoscopic segmentectomy 2. This study aimed to present the standardization of laparoscopic segmentectomy 2 with surgical outcomes. METHODS: This study included seven patients who underwent pure laparoscopic segmentectomy 2 by the Glissonean approach from January 2020 to December 2021. Four of them had hepatocellular carcinoma, two had colorectal liver metastasis, and one had hepatic angiomyolipoma, which was preoperatively diagnosed with hepatocellular carcinoma. In all patients, preoperative three-dimensional (3D) simulation images from dynamic CT were reconstructed using a 3D workstation. The layer between the hepatic parenchyma and the Glissonean pedicle of segment 2 (G2) was dissected to encircle the root of G2. After clamping or ligation of the G2, 2.5 mg of indocyanine green was injected intravenously to identify the boundaries between segments 2 and 3 with a negative staining method under near-infrared light. Parenchymal transection was performed from the caudal side to the cranial side according to the demarcation on the liver surface, and the left hepatic vein was exposed on the cut surface if possible. RESULTS: The mean operative time for all patients was 281 min. The mean blood loss was 37 mL, and no transfusion was necessary. Estimated liver resection volumes significantly correlated with actual liver resection volumes (r = 0.61, P = 0.035). After the operation, one patient presented with asymptomatic deep venous and pulmonary thrombosis, which was treated with anticoagulant therapy. The mean length of hospital stay was 8.9 days. CONCLUSION: Laparoscopic segmentectomy 2 by the Glissonean approach is a feasible and safe procedure with the preservation of the nontumor-bearing segment 3 for liver tumors in segment 2.

Successful left hepatic trisectionectomy after portal vein embolization for colon cancer liver metastasis in a patient with right-sided ligamentum teres.

Right-sided ligamentum teres (RSLT) is a rare congenital anomaly in which the fetal umbilical vein is connected to the right paramedian trunk of the portal vein. An 80-year-old woman underwent curative sigmoidectomy for sigmoid cancer 3 years prior to presentation. After 1 year, small solitary liver metastasis was noted in segment 4. Because the patient experienced recurrence of the same lesion after chemotherapy and radiofrequency ablation, she was referred to our hospital. CT revealed an anomaly of the liver with RSLT, classified as an independent posterior branch type. The tumor in the left paramedian section was located in the right umbilical portion (RUP), and BDTT was advanced to the common bile duct. Because the estimated future remnant liver volume was 35.2%, transileocecal portal vein embolization (PVE) for the portal branches from the RUP increased it to 43.5% in 3 weeks. Left trisectionectomy with extrahepatic bile duct resection and hepaticojejunostomy were performed. The patient was discharged on postoperative day 75. We successfully performed a left trisectionectomy after PVE in a patient with RSLT. Understanding the vascular and biliary anomalies of patients with RSLT is essential. When the future remnant liver is small, PVE can be considered for safe hepatectomy.

Successful recanalization of completely obstructed portal vein thrombosis after right hepatectomy for perihilar cholangiocarcinoma by aspiration thrombectomy via the ileocolic mesenteric vein and subsequent systemic anticoagulation with edoxaban.

Portal vein thrombosis (PVT) is a lethal complication of hepatectomy if not properly treated. An 81-year-old woman diagnosed with postoperative PVT after right hepatectomy and caudate lobectomy for perihilar cholangiocarcinoma. Elevation of serum total bilirubin levels, D-dimer levels, and glossy ascites appeared on postoperative day 5 (POD5), and a contrast-enhanced CT confirmed PVT. Thrombi were found from the umbilical portion of the portal vein to the superior mesenteric vein. There were signs of acute liver failure due to thrombi obstructing the portal vein. Therefore, emergent catheter thrombus aspiration was performed under laparotomy. An aspiration catheter was inserted into the superior mesenteric vein from the ileocolic vein. We performed direct aspiration thrombectomy, followed by anticoagulant administration using urokinase via the catheter. Partial recanalization of the portal vein and superior mesenteric vein was observed. To dissolve residual thrombi, edoxaban administration was started on POD6. Contrast-enhanced CT 16 days after her additional operation showed the thrombi had completely disappeared. The patient was discharged on POD76. She had no recurrence of PVT over the next 6 months. Combination therapy of early intervention using aspiration catheter and systemic anticoagulant medication was useful for severe postoperative PVT accompanied with liver failure.

Prognostic Impact of Inflammation-Based Scores for Extrahepatic Cholangiocarcinoma.

INTRODUCTION: Although the relationship between systemic inflammatory responses and prognosis has been known in various cancers, it remains unclear which scores are most valuable for determining the prognosis of extrahepatic cholangiocarcinoma. We aimed to verify the usefulness of various inflammation-based scores as prognostic factors in patients with resected extrahepatic cholangiocarcinoma. METHODS: We analyzed consecutive patients undergoing surgical resection for extrahepatic cholangiocarcinoma at our institution between January 2000 and December 2019. The usefulness of the following inflammation-based scores as prognostic factor was investigated: glasgow prognostic score (GPS), modified GPS, neutrophil-to-lymphocyte ratio, platelet to lymphocyte ratio, lymphocyte-to-monocyte ratio, prognostic nutrition index, C-reactive protein to albumin ratio (CAR), controlling nutritional status (CONUT), and prognostic index. RESULTS: A total of 169 patients were enrolled in this study. Of the nine scores, CAR and CONUT indicated prognostic value. Furthermore, multivariate analysis for overall survival revealed that high CAR (>0.23) was an independent prognostic factor (hazard ratio: 1.816, 95% confidence interval: 1.135-2.906, p = 0.0129), along with lymph node metastasis and curability. There was no difference in tumor staging and short-term outcomes between the low CAR (≤0.23) and high CAR groups. CONCLUSIONS: CAR was the most valuable prognostic score in patients with resected extrahepatic cholangiocarcinoma.

Standardization of the Side-to-Side Cavo-Caval Anastomosis in Orthotopic Liver Transplantation Based on the Causal Analysis of Outflow Obstruction.

BACKGROUND: Although liver transplantation is widely accepted as the therapeutic strategy for end-stage liver failure, complication of hepatic venous outflow obstruction remains lethal. Currently, ensuring a single wide orifice in both the graft and recipient inferior vena cava has been proposed to avoid hepatic venous outflow obstruction with no theoretical concept. METHODS: We herein report a standardization technique for the reconstruction of the hepatic vein based on the causal analysis. RESULTS: During the put-in process, the graft must be positioned in contact with the recipient diaphragm and slightly pushed to the cranial direction to simulate the state after abdominal closure. Because there is no extra space between the graft and diaphragm, the graft could not rotate about the anastomotic site of the inferior vena cava toward the diaphragm after abdominal closure as the intestinal pressure increases, and accordingly hepatic venous outflow obstruction does not develop. CONCLUSIONS: With this concept, all transplant surgeons can successfully and easily perform hepatic vein reconstruction without total clamping of the inferior vena cava and without outflow block.

Indocyanine green (ICG) fluorography and digital subtraction angiography (DSA) of vessels supplying the remnant stomach that were performed during distal pancreatectomy in a patient with a history of distal gastrectomy: a case report.

A 68-year-old man who had undergone distal gastrectomy for gastric cancer 3 years previously, presented to our hospital for examination of dilatation of the main pancreatic duct on follow-up computed tomography and magnetic resonance cholangiopancreatography. After examination, he was diagnosed with early-stage pancreatic cancer and distal pancreatectomy (DP) was planned. With informed consent, we performed indocyanine green (ICG) fluorography during DP and digital subtraction angiography (DSA) of vessels supplying the remnant stomach immediately before and after DP. On ICG fluorography, the remnant stomach gradually became fluoresced starting at the area of the lesser curvature, and the fluorescence eventually intensified over the entire area of the remnant stomach to the same brightness as that of the liver and duodenum. On DSA following DP, the terminal branches of the left inferior phrenic artery (LIPA) were distributed to more than half of the area of the remnant stomach, centering around the proximal area. It is useful to confirm blood flows to the remnant stomach by ICG fluorography using a near-infrared imaging camera during DP. We found that the LIPA played an important role in maintaining the blood supply to the remnant stomach in the absence of the left gastric artery and splenic artery.

Influence of the Retrocolic Versus Antecolic Route for Alimentary Tract Reconstruction on Delayed Gastric Emptying After Pancreatoduodenectomy: A Multicenter, Noninferiority Randomized Controlled Trial.

OBJECTIVE: This study aimed to determine whether retrocolic alimentary tract reconstruction is noninferior to antecolic reconstruction in terms of DGE incidence after pancreatoduodenectomy (PD) and investigated patients' postoperative nutritional status. SUMMARY OF BACKGROUND DATA: The influence of the route of alimentary tract reconstruction on DGE after PD is controversial. METHODS: Patients from 9 participating institutions scheduled for PD were randomly allocated to the retrocolic or antecolic reconstruction groups. The primary outcome was incidence of DGE, defined according to the 2007 version of the International Study Group for Pancreatic Surgery definition. Noninferiority would be indicated if the incidence of DGE in the retrocolic group did not exceed that in the antecolic group by a margin of 10%. Patients' postoperative nutrition data were compared as secondary outcomes. RESULTS: Total, 109 and 103 patients were allocated to the retrocolic and antecolic reconstruction group, respectively (n = 212). Baseline characteristics were similar between both groups. DGE occurred in 17 (15.6%) and 13 (12.6%) patients in the retrocolic and antecolic group, respectively (risk difference; 2.97%, 95% confidence interval; -6.3% to 12.6%, which exceeded the specified margin of 10%). There were no differences in the incidence of other postoperative complications and in the duration of hospitalization. Postoperative nutritional indices were similar between both groups. CONCLUSIONS: This trial could not demonstrate the noninferiority of retrocolic to antecolic alimentary tract reconstruction in terms of DGE incidence. The alimentary tract should not be reconstructed via the retrocolic route after PD, to prevent DGE.

Proton Radiotherapy for Isolated Local Recurrence of Primary Resected Pancreatic Ductal Adenocarcinoma.

BACKGROUND: The optimal treatment for isolated local recurrence (ILR) of pancreatic adenocarcinoma (PDAC) after surgical resection remains unclear. This study aimed to evaluate the safety and efficacy of proton radiotherapy (PRT) for ILR of PDAC after surgery. METHODS: The medical records of patients with ILR of PDAC after surgery who underwent proton beam therapy between 2011 and 2015 at Hyogo Ion Beam Medical Center were retrospectively studied. RESULTS: The study analyzed 30 patients (14 women and 16 men) with a median age of 65 years (range 38-81 years) who had initially undergone pancreatoduodenectomy (n = 23) or distal pancreatectomy (n = 7) for their primary tumors. Upon ILR, PRT was administered with a median total cumulative dose of 67.5 gray equivalent (GyE) (range 50-67.5 GyE) using 19 to 25 fractions. For 25 patients, concurrent chemotherapy was administered using gemcitabine (n = 18) or S-1 (n = 7). Four patients (13.3%) experienced acute grade ≥ 3 gastrointestinal toxicities. After a median follow-up period of 17.6 months (range 2.1-50.4 months), 23 patients had experienced tumor progression and 10 had died. Nine patients (30%) experienced local tumor progression. The median overall, progression-free, and local progression-free survival rates were 26.1, 12.3, and 41.2 months, respectively. Pre-PRT serum levels of cancer antigen 19-9 higher than 100 U/mL and duke pancreatic monoclonal antigen type 2 higher than 150 U/mL were significantly associated with shorter progression-free survival rates. CONCLUSIONS: Proton radiotherapy for ILR of PDAC after surgery is well tolerated and produces good locoregional control and should be considered for eligible patients.