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In this study, we investigated reversible intermolecular proton shifting (IPS) coupled with spin transition (ST) in a novel FeII complex. The host FeII complex and the guest carboxylic acid anion were connected by intermolecular hydrogen bonds (IHBs). We extended the intramolecular proton transfer coupled ST phenomenon to the intermolecular system. The dynamic phenomenon was confirmed by variable-temperature single-crystal X-ray diffraction, neutron crystallography, and infrared spectroscopy. The mechanism of IPS was further validated using density functional theory calculations. The discovery of IPS-coupled ST in crystalline molecular materials provides good insights into fundamental processes and promotes the design of novel multifunctional materials with tunable properties for various applications, such as optoelectronics, information storage, and molecular devices.
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In quantum magnetic materials, ordered phases induced by an applied magnetic field can be described as the Bose-Einstein condensation (BEC) of magnon excitations. In the strongly frustrated system SrCu2(BO3)2, no clear magnon BEC could be observed, pointing to an alternative mechanism, but the high fields required to probe this physics have remained a barrier to detailed investigation. Here we exploit the first purpose-built high-field neutron scattering facility to measure the spin excitations of SrCu2(BO3)2 up to 25.9 T and use cylinder matrix-product-states (MPS) calculations to reproduce the experimental spectra with high accuracy. Multiple unconventional features point to a condensation of S = 2 bound states into a spin-nematic phase, including the gradients of the one-magnon branches and the persistence of a one-magnon spin gap. This gap reflects a direct analogy with superconductivity, suggesting that the spin-nematic phase in SrCu2(BO3)2 is best understood as a condensate of bosonic Cooper pairs.
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The structure of a recently found hyperhydrated form of sodium chloride (NaCl·13H2O and NaCl·13D2O) has been determined by in situ single-crystal neutron diffraction at 1.7â GPa and 298â K. It has large hydrogen-bond networks and some water molecules have distorted bonding features such as bifurcated hydrogen bonds and five-coordinated water molecules. The hydrogen-bond network has similarities to ice VI in terms of network topology and disordered hydrogen bonds. Assuming the equivalence of network components connected by pseudo-symmetries, the overall network structure of this hydrate can be expressed by breaking it down into smaller structural units which correspond to the ice VI network structure. This hydrogen-bond network contains orientational disorder of water molecules in contrast to the known salt hydrates. An example is presented here for further insights into a hydrogen-bond network containing ionic species.
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Multiple proton transfer (PT) controllable by external stimuli plays a crucial role in fundamental chemistry, biological activity, and material science. However, in crystalline systems, controlling multiple PT, which results in a distinct protonation state, remains challenging. In this study, we developed a novel tridentate ligand and iron(II) complex with a short hydrogen bond (HB) that exhibits a PT-coupled spin transition (PCST). Single-crystal X-ray and neutron diffraction measurements revealed that the positions of the two protons in the complex can be controlled by temperature and photoirradiation based on the thermal- and photoinduced PCST. The obtained results suggest that designing molecules that form short HBs is a promising approach for developing multiple PT systems in crystals.
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In condensed matter physics, pressure is frequently used to modify the stability of both electronic states and atomic arrangements. Under isotropic pressure, the intermetallic compound MnP has recently attracted attention for the interplay between pressure-induced superconductivity and complicated magnetic order in the vicinity . By contrast, we use uniaxial stress, a directional type of pressure, to investigate the effect on the magnetism and crystal structure of this compound. An irreversible magnetisation response induced by uniaxial stress is discovered in MnP at uniaxial stress as low as [Formula: see text]. Neutron diffraction experiments reveal that uniaxial stress forms crystal domains that satisfy pseudo-rotational symmetry unique to the MnP-type structure. The structure of the coexisting domains accounts for the stress-induced magnetism. We term this first discovered phenomenon atomic reconstruction (AR) induced by uniaxial stress. Furthermore, our calculation results provide guidelines on the search for AR candidates. AR allows crystal domain engineering to control anisotropic properties of materials, including dielectricity, elasticity, electrical conduction, magnetism and superconductivity. A wide-ranging exploration of potential AR candidates would ensure that crystal domain engineering yields unconventional methods to design functional multi-domain materials for a wide variety of purposes.
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OBJECTIVE: The aim of the present randomized controlled trial was to evaluate the superiority of indocyanine green fluorescence imaging (ICG-FI) in reducing the rate of anastomotic leakage in minimally invasive rectal cancer surgery. BACKGROUND: The role of ICG-FI in anastomotic leakage in minimally invasive rectal cancer surgery is controversial according to the published literature. METHODS: This randomized, open-label, phase 3, trial was performed at 41 hospitals in Japan. Patients with clinically stage 0-III rectal carcinoma less than 12 cm from the anal verge, scheduled for minimally invasive sphincter-preserving surgery were preoperatively randomly assigned to receive a blood flow evaluation by ICG-FI (ICG+ group) or no blood flow evaluation by ICG-FI (ICG- group). The primary endpoint was the anastomotic leakage rate (grade A+B+C, expected reduction rate of 6%) analyzed in the modified intention-to-treat population. RESULTS: Between December 2018 and February 2021, a total of 850 patients were enrolled and randomized. After the exclusion of 11 patients, 839 were subject to the modified intention-to-treat population (422 in the ICG+ group and 417 in the ICG- group). The rate of anastomotic leakage (grade A+B+C) was significantly lower in the ICG+ group (7.6%) than in the ICG- group (11.8%) (relative risk, 0.645; 95% confidence interval 0.422-0.987; P =0.041). The rate of anastomotic leakage (grade B+C) was 4.7% in the ICG+ group and 8.2% in the ICG- group ( P =0.044), and the respective reoperation rates were 0.5% and 2.4% ( P =0.021). CONCLUSIONS: Although the actual reduction rate of anastomotic leakage in the ICG+ group was lower than the expected reduction rate and ICG-FI was not superior to white light, ICG-FI significantly reduced the anastomotic leakage rate by 4.2%.
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Verde de Indocianina , Neoplasias del Recto , Humanos , Fuga Anastomótica/prevención & control , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/cirugía , Perfusión , Imagen Óptica/métodos , Anastomosis Quirúrgica/métodosRESUMEN
The application of single-crystal neutron diffraction (SCND) to observe proton-transfer phenomena in crystalline compounds exhibiting unusual protonation states or proton dynamics has garnered significant research interest in recent years. However, proton tautomerism, which results in different protonation states before and after proton transfer, has never been observed using the SCND technique. Thus, to observe the proton tautomerism phenomenon by SCND measurements, we developed an iron(II) complex that forms a large crystal and exhibits a proton-transfer-coupled spin transition (PCST). The presence of the two types of proton tautomers was determined by conventional analysis of the proton position by X-ray crystallography, infrared spectroscopy, and density functional theory calculations. Finally, our results confirmed that proton tautomerism was successfully observed for the first time using variable-temperature SCND measurements.
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The study presents the case of a 71-year-old woman who visited a nearby hospital for epigastric pain and weight loss. A CT scan showed a mass in the gallbladder, and the CEA level was high, so she was referred to our hospital for further investigation. Abdominal US, CT, and MRI suggested gallbladder cancer with para-aortic metastasis, and the histological findings on the EUS-FNA confirmed the diagnosis. Since surgical resection was not indicated, chemotherapy was performed(gemcitabine plus cisplatin). After 10 courses of chemotherapy, CT and MRI showed downsizing of para-aortic lymph nodes, and no accumulation of FDG was found on FDG-PET. Confirming the downstaging of cancer, conversion surgery, comprising an extended cholecystectomy and a lymph node resection, was performed. The pathological diagnosis showed no lymph node metastasis. No recurrence was observed after 12 months of surgery. Initially, unresectable gallbladder cancer with para-aortic lymph node metastasis was indicated to be compatible with preoperative chemotherapy and conversion surgery.
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Carcinoma in Situ , Neoplasias de la Vesícula Biliar , Femenino , Humanos , Anciano , Neoplasias de la Vesícula Biliar/tratamiento farmacológico , Neoplasias de la Vesícula Biliar/cirugía , Neoplasias de la Vesícula Biliar/patología , Fluorodesoxiglucosa F18/uso terapéutico , Ganglios Linfáticos/patología , Desoxicitidina/uso terapéutico , Escisión del Ganglio Linfático , Cisplatino/uso terapéutico , Carcinoma in Situ/cirugíaRESUMEN
PURPOSE: To evaluate the efficacy and safety of the enhanced recovery after surgery (ERAS) protocol and quantify the impact of each ERAS item on postoperative outcomes. METHODS: We used a generalized linear model to compare 289 colorectal cancer patients treated with the ERAS protocol between June, 2015 and April, 2021, with 99 colorectal cancer patients treated with the conventional colorectal surgery pathway between April, 2014 and June, 2015. RESULTS: The median length of hospital stay (LOHS) was significantly shorter in the ERAS group, at 9 days (range 3-104 days) vs. 14 days (range 4-44 days) (p < 0.001), but the complication rates (Clavien-Dindo grade 2 or more) were similar (16.6% vs. 22.2%; p = 0.227). However, in the ERAS group, the higher the compliance with ERAS items, the lower the complication rate and LOHS (both p < 0.001). Multiple regression analysis demonstrated that "Discontinuation of continuous intravenous infusion on POD1" and "Avoidance of fluid overload" were significantly associated with the LOHS (p < 0.001 and p = 0.008). CONCLUSION: The ERAS protocol is safe and effective for elective colorectal cancer surgery, and compliance with the ERAS protocol contributes to shorter LOHS and fewer complications. Items related to perioperative fluid management had a crucial impact on these outcomes.
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Neoplasias Colorrectales , Recuperación Mejorada Después de la Cirugía , Humanos , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Atención Perioperativa/efectos adversos , Atención Perioperativa/métodos , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/complicacionesRESUMEN
A 78-year-old man was diagnosed as HER2-positive unresectable advanced gastric cancer(cT4aN3M1[LYM], Stage â £). After 2 courses of first-line chemotherapy(S-1 plus oxaliplatin plus trastuzumab), PR was achieved. The treatment could not be continued due to adverse events after 5 courses, thus second-line chemotherapy was conducted. Corresponding to the physical condition. The third-line chemotherapy was also introduced. However, we clinically judged PD because of amount of ascites and chemotherapy was terminated. After that, he has survived for more than 2 years without chemotherapy, and endoscopy and CT showed the disappearance of the tumor, metastatic lymph nodes, and ascites at 41 months after diagnosis. Looking back on the changes in tumor markers, it was possible that he had already achieved CR at the first-line chemotherapy.
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Neoplasias Gástricas , Anciano , Humanos , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ascitis , Gastrectomía , Receptor ErbB-2 , Neoplasias Gástricas/tratamiento farmacológico , TrastuzumabRESUMEN
A 78-year-old man was diagnosed with lymph node metastasis 2 months after surgery for gastric neuroendocrine carcinoma. He received chemotherapy(CDDP plus CPT-11)and showed partial response(PR)after 3 courses of the regimen. Serum CEA increased 5 months after surgery, thus nab-paclitaxel plus ramucirumab was administered. Although the lymph node kept shrinked after 2 courses of the regimen, the lymph node was detected 12 cm of the size in CT after 5 courses of the regimen. He started to receive nivolumab. The lymph nodes showed PR after 4 courses, and complete response after 6 courses of the regimen for 1 year and 4 months until now.
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Carcinoma Neuroendocrino , Neoplasias Gástricas , Masculino , Humanos , Anciano , Nivolumab/uso terapéutico , Metástasis Linfática , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Gastrectomía , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugía , Cisplatino/uso terapéutico , Irinotecán , Carcinoma Neuroendocrino/tratamiento farmacológico , Carcinoma Neuroendocrino/cirugía , Ganglios LinfáticosRESUMEN
A 52-year-old man underwent total gastrectomy for gastric cancer and chemoradiotherapy for thoracic paraaortic lymph node metastasis. He also underwent esophageal stent implantation for stenosis. He was admitted to our hospital with fever and breathing difficulty and was diagnosed with infectious pericarditis. He showed symptoms of shock due to cardiac tamponade. After pericardial drainage, his vital signs improved. When signs of infection are detected in patients with a history of chemoradiotherapy or stent implantation, we should consider infectious pericarditis due to esophageal pericardial fistula and apply immediate drainage of cardiac tamponade.
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Taponamiento Cardíaco , Fístula Esofágica , Pericarditis , Neoplasias Gástricas , Masculino , Humanos , Persona de Mediana Edad , Taponamiento Cardíaco/etiología , Taponamiento Cardíaco/terapia , Neoplasias Gástricas/cirugía , Metástasis Linfática , Terapia CombinadaRESUMEN
Magnetic superconductors are specific materials exhibiting two antagonistic phenomena, superconductivity and magnetism, whose mutual interaction induces various emergent phenomena, such as the reentrant superconducting transition associated with the suppression of superconductivity around the magnetic transition temperature (T m), highlighting the impact of magnetism on superconductivity. In this study, we report the experimental observation of the ferromagnetic order induced by superconducting vortices in the high-critical-temperature (high-T c) magnetic superconductor EuRbFe4As4 Although the ground state of the Eu2+ moments in EuRbFe4As4 is helimagnetism below T m, neutron diffraction and magnetization experiments show a ferromagnetic hysteresis of the Eu2+ spin alignment. We demonstrate that the direction of the Eu2+ moments is dominated by the distribution of pinned vortices based on the critical state model. Moreover, we demonstrate the manipulation of spin texture by controlling the direction of superconducting vortices, which can help realize spin manipulation devices using magnetic superconductors.
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During the followâup of Vater papillary adenoma, a 74âyearâold man was admitted to our hospital with a chief complaint of upper abdominal pain and diagnosed as cholangitis with obstructive jaundice. Cholestasis had been considered to be caused by papillary adenoma, however, EUS exam showed continuous bile duct wall irregularity from papilla of Vater. So we diagnosed as papillary carcinoma with extension to the distal bile duct. Preoperative CT showed the stenosis at the root of celiac artery, and hepatic blood flow was considered to be supplied via the pancreatic head arcade from superior mesenteric artery, so an anastomosis of gastroduodenal artery and inferior pancreaticoduodenal artery was performed during pancreaticoduodenectomy( PD). Like this case, when performing PD with celiac artery stricture, it is important to evaluate hepatic blood flow before and during surgery and prepare for the arterial reconstruction.
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Carcinoma Papilar , Pancreaticoduodenectomía , Anciano , Anastomosis Quirúrgica , Arteria Celíaca/cirugía , Constricción Patológica/etiología , Constricción Patológica/cirugía , Humanos , MasculinoRESUMEN
Primary duodenal carcinoma is a rare disease among gastrointestinal malignancies and has little evidence. We evaluated retrospectively the treatment status of 16 cases of primary duodenal carcinoma in our hospital between 2010 and 2019. The median age was 72(58-88)years and 63% of patients were male, and Each stage were Stage 0 in 4 cases, Stage â in 1 case, Stage â ¢A in 2 cases, Stage â ¢B in 3 cases, and Stage â £ in 6 cases(UICC 8th edition). Initial treatment was endoscopic therapy in 3 cases, surgery in 10 cases, chemotherapy in 1 case, and best supportive care in 2 case. The 2-year survival rate was 51.3% and the MST was 25.4 months in all cases. The Stage 0, Stage â cases had all recurrence-free survival, while the Stage â ¢A or higher cases, 2-year survival rate was 33.8% and the MST was 20.0 months. Also, XELOX was often selected as the first-line treatment for chemotherapy regimens including recurrence treatment.
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Carcinoma , Recurrencia Local de Neoplasia , Anciano , Anciano de 80 o más Años , Hospitales , Humanos , Masculino , Estadificación de Neoplasias , Pronóstico , Estudios RetrospectivosRESUMEN
A 65-year-old man with 1 month of general malaise was admitted to our hospital. Thoracoabdominal CT showed that the supra-clavicular, sub-carina, and para-aortic lymph nodes were swelling. Upper gastrointestinal endoscopy revealed 2 type 1 tumors at the esophagogastric junction, and the biopsy showed Group 5, well to moderately differentiated adenocarcinoma. The clinical diagnosis was cardiac gastric cancer and cStage â £(cT3N3M1[LYM]). We started capecitabine plus oxaliplatin as the first-line chemotherapy, and weekly paclitaxel plus ramucirumab was administered as the second-line treatment. The second-line treatment was successful, and the effect of PR was obtained. However, considering the period of TTF, while the therapeutic effect continued, we switched to third-line treatment with nivolumab after 7 courses of the second treatment. With the third-line treatment, PR was maintained for 1 year and 3 months, and good quality of life and performance status were obtained for a long period without irAE. However, after 32 courses, because the tumor marker was elevated and lymph nodes were enlarged, we judged PD and switched to the fourth-line treatment with nab-paclitaxel plus ramucirumab. The tumor marker levels decreased, the lymph nodes shrank, and PR was achieved again with the fourth-line treatment. The treatment is still ongoing 2 year and 8 months after the diagnosis.
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Nivolumab , Neoplasias Gástricas , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Unión Esofagogástrica , Humanos , Ganglios Linfáticos , Masculino , Nivolumab/uso terapéutico , Calidad de Vida , Neoplasias Gástricas/tratamiento farmacológicoRESUMEN
A 75-year-old man was admitted to our hospital for breathing difficulty. CT showed a 20 cm mass with clear boundaries and internal non-uniformity, which we suspected to be a gastrointestinal stromal tumor(GIST). Surgical resection was been considered to be risky because the mass was close to surrounding organs, such as the stomach, liver and diaphragm. Thus, we chose imatinib therapy. After 2 months, he was admitted to our hospital for anemia. CT showed the size of mass to be smaller, but the area of low density with internal non-uniformity had increased. We diagnosed intratumoral bleeding, and chose surgical resection. The mass was under the omentum, and had infiltrated the extrahepatic area and lesser curvature of the stomach. We diagnosed the mass derived from the stomach, and performed partial gastrectomy with partial liver resection. Pathological diagnosis was extrahepatically growing hepatocellular carcinoma(HCC, pT3N0M0, pStage â ¢).
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Carcinoma Hepatocelular , Tumores del Estroma Gastrointestinal , Neoplasias Hepáticas , Neoplasias Gástricas , Anciano , Carcinoma Hepatocelular/cirugía , Gastrectomía , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/cirugía , Humanos , Mesilato de Imatinib , Neoplasias Hepáticas/cirugía , Masculino , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugíaRESUMEN
Case 1: A 67-year-old male had a type 1 tumor in the stomach with a lymph node metastasis 50 mm in size. He was diagnosed with cT4aN(+)M0, cStage â ¢ and received preoperative docetaxel plus oxaliplatin plus S-1(DOS)therapy. After 3 courses of the regimen, the patient underwent laparoscopic total gastrectomy. The final stage was ypT3N1(1/38) M0, ypStage â ¡B, R0, and the pathological response was Grade 2b. Case 2: A 64-year-old male had a type 3 tumor in the abdominal esophagus and a lymph node metastasis 15 mm in size. He was diagnosed with cT3N(+)M0, cStage â ¢ and received preoperative DOS therapy. After 3 courses, he underwent laparoscopic esophagectomy. The final stage was ypT0N0M0, ypStage 0, R0, and the pathological response was Grade 3. DOS therapy may be effective as a neoadjuvant chemotherapy.
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Terapia Neoadyuvante , Neoplasias Gástricas , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Combinación de Medicamentos , Gastrectomía , Humanos , Masculino , Persona de Mediana Edad , Oxaliplatino/uso terapéutico , Ácido Oxónico/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugía , Tegafur/uso terapéuticoRESUMEN
Case 1, the patient was a 51-year-old man. Upper gastrointestinal endoscopy revealed a submucosal tumor with delle at the posterior wall of the gastric body, and the biopsy demonstrated a diagnosis of GIST. Abdominal CT scan showed a tumor at the size of 130×110×90 mm. Six months after administration of 400 mg/day of imatinib, the maximum diameter was reduced to 55 mm, then partial gastrectomy was performed by laparoscopic surgery. He continued to take imatinib after the surgery for 3 years, and he is alive without recurrence 4 years postoperatively. Case 2, the patient was a 68-year-old man. An abdominal CT scan showed a tumor at the size of 160×120×85 mm on the posterior outside of the stomach, but no submucosal tumor could be identified by upper gastrointestinal endoscopy. Gastric GIST was suspected and he started taking imatinib 400 mg/day. Because the Grade 3 generalized eruption was appeared, imatinib was discontinued, and then the dose was reduced. Nine months after the initiation of the treatment, the maximum diameter was reduced to 90 mm, and laparoscopic partial gastrectomy was performed. The patient is followed up without administration of imatinib after the surgery, and is alive without recurrence for 1 year and 6 months postoperatively. We report 2 cases that the large gastric GIST was able to be resected safely and completely due to tumor shrinkage by neoadjuvant imatinib therapy.
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Antineoplásicos , Tumores del Estroma Gastrointestinal , Laparoscopía , Neoplasias Gástricas , Anciano , Antineoplásicos/uso terapéutico , Gastrectomía , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/cirugía , Humanos , Mesilato de Imatinib/uso terapéutico , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugíaRESUMEN
The patient was a 72-year-old man with a history of pancreatic cancer and IPMA treated with distal pancreatectomy. He had recurrence-free period after adjuvant chemotherapy with S-1. But 6 years after the surgery, a diameter of 1 cm mass was noted in the remnant pancreas on MRI examination after hepatocellular carcinoma treatment. The mass was diagnosed as remnant pancreatic cancer, and he had undergone partial pancreatectomy of remnant pancreas. The pathological diagnosis was pancreatic ductal carcinoma with negative margin. However, 6 months after the reoperation, epigastric pain appeared, and CT scan showed a pseudocyst of 10 cm in size. The diagnosis was local recurrence with positive cytology, and then puncture drainage was performed. After repeated drainages, adhesion of the cystic lesion, and chemotherapy, the cytology became negative and the cystic lesion disappeared, but peritoneal dissemination metastasis also appeared. The patient died of the primary disease 7 years and 8 months after the first surgery and 1 year and 11 months after the second surgery. There has been no report of local recurrence in the form of pancreatic pseudocyst after pancreatic cancer surgery, and we report this case with literature discussion.