Risk factors for early recurrence in patients with pancreatic ductal adenocarcinoma who underwent curative resection.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, and surgical resection is the only potentially curative approach. However, the rate of recurrence remains high, particularly within the first 6 months, and is associated with a poor prognosis. The present study evaluated the clinical characteristics and risk factors for early recurrence in pancreatic ductal adenocarcinoma (PDAC) patients who underwent curative resection, regardless of the use of neoadjuvant chemotherapy, to identify predictive factors associated with early recurrence and poor outcomes as well as to determine the optimal treatment strategy for patients at high risk of early recurrence after surgical resection. METHODS: Patients who underwent pancreatic resection for PDAC at our institution from 2013 to 2021 were included in this study. We investigated the clinicopathological features of patients in groups: those with recurrence within 6 months, recurrence between 6 and 12 months, and recurrence beyond 12 months or no recurrence. A logistic regression analysis identified covariates associated with early recurrence at 6 and 12 months. RESULTS: The study included 403 patients with a median follow-up of 25.7 months. Recurrence was observed in 279 patients, with 14.6% recurring within 6 months, 23.3% within 6-12 months, and 62% after 12 months or not at all. The preoperative CA19-9 level, modified Glasgow prognostic score (mGPS), and positive peritoneal cytology were significant risk factors for early recurrence within 6 months, while positive peritoneal cytology, lymph node metastasis, and the absence of adjuvant chemotherapy were significant risk factors for recurrence within 12 months. For patients who received preoperative chemotherapy or chemoradiotherapy, the preoperative CA19-9 level, mGPS, and positive peritoneal cytology were significant independent risk factors for early recurrence within 6 months, while positive peritoneal cytology, lymph node metastasis, and the absence of adjuvant chemotherapy were significant independent risk factors for recurrence within 12 months. The study concluded that the overall survival after surgical resection for potentially resectable PDAC worsened according to the number of risk factors present in the patient. CONCLUSIONS: We clarified that preoperative CA19-9, positive peritoneal cytology, and the lack of adjuvant chemotherapy were consistent predictors for early recurrence within 6 and 12 months. In addition, an increased number of risk factors affecting the patient was associated with a poorer overall survival after potentially curable resection. Calculating the number of risk factors for early recurrence may be an essential predictive factor when considering treatment strategies.

Postoperative acute pancreatitis after pancreatic resection in patients with pancreatic ductal adenocarcinoma.

INTRODUCTION: Postoperative pancreatic fistula (POPF) is one of the major critical complications after pancreatic resection. Recently, postoperative acute pancreatitis (POAP), a new concept for a pancreatic-specific complication following pancreatic resection, has been advocated, and its association with POPF has been reported. The present study examined the clinical features of POAP and identified the associations of POAP with POPF and other postoperative morbidities in pancreatic ductal adenocarcinoma (PDAC) patients undergoing pancreatic resection. METHODS: A total of 312 consecutive patients who underwent pancreatic resection for PDAC at our institution from 2013 to 2019 were enrolled in this study. POAP was defined as an elevated serum amylase level above the upper limit normal on postoperative day (POD) 0 or 1, based on Connor's definition. The severity of POPF was assessed by the International Study Group on Pancreatic Surgery definition. RESULTS: A total of 184 patients (58.9%) had POAP. POAP occurred in 58.5% of subtotal stomach-preserving pancreatoduodenectomy patients and 60% of distal pancreatectomy combined with splenectomy patients. The presence of POAP was significantly associated with the development of clinically relevant POPF, higher rates of severe morbidity, and a prolonged hospital stay after pancreatic resection. A multivariate analysis showed that the presence of POAP and elevated C-reactive protein levels on POD 3 were independent predictors of clinically relevant POPF after subtotal stomach-preserving pancreatoduodenectomy. CONCLUSIONS: POAP is associated with the development of POPF, higher rates of severe morbidity, and a prolonged hospital stay after pancreatic resection and is an independent risk factor for clinically relevant POPF after pancreatoduodenectomy. POAP represents an important indicator for planning treatment strategies to prevent serious complications, including POPF.

[Curative Resection of Pancreatic Head Cancer with Liver Metastasis after GEM plus Nab-PTX Therapy].

A 63-year-old man was admitted to our hospital for examination and treatment of a pancreatic head tumor detected at a nearby hospital. After CT, EUS-FNA, and PET-CT, he was diagnosed with unresectable pancreatic cancer with liver metastasis. After 9 courses of gemcitabine and nab-paclitaxel therapy, the primary tumor was dramatically reduced in size and the liver metastasis had disappeared. He underwent subtotal stomach-preserving pancreaticoduodenectomy. The postoperative diagnosis according to the General Rules of the Study of Pancreatic Cancer(7th edition)was Ph, TS1(15mm), adenosquamous carcinoma, ypT3, ypRP1, ypPL1, R0, ypN0(0/29), M0, CY0, ypStage ⅡA. The histological response was Grade 2. The patient remains alive without recurrence 5 months after surgical resection.

[Evaluation of Body Temperature during Pancreaticoduodenectomy for Pancreatic Cancer in Elderly Patients Aged over 75 Years Old].

BACKGROUND: Body temperatures in elderly patients undergoing a pancreaticoduodenectomy(PD)for treatment of pancreatic cancer have not been fully evaluated. We aimed to compare body temperature during a PD between elderly(75 years old)and non-elderly patients. METHODS: This retrospective study included patients who underwent PD between April 2012 and April 2014 at the Kanasgawa Cancer Center. Patients were categorized into 2 groups: elderly patients(≥75 years of age: group A)and non-elderly patients(<75 years of age: group B). Body temperatures were compared between the groups. RESULTS: We evaluated 58 patients-14 were classified into group A, and 44 into group B. Preoperative clinicopathological outcomes demonstrated no significant differences between patients. A comparison of body temperatures between the groups showed 36.3°C(before surgery)/36.1°C(at 1 hr)/36.3°C(at 2 hr)/36.7°C(at 3 hr)/36.8°C(at 4 hr)/37.1°C(at 5 hr)/37.4°C(at 6 hr)in group A compared to 36.2°C(before surgery)/36.2°C(at 1 hr)/36.4°C(at 2 hr)/36.6°C(at 3 hr)/ 36.9°C(at 4 hr)/37.0°C(at 5 hr)/37.3°C(at 6 hr)in group B. Results did not significantly differ between the groups. CONCLUSIONS: Our study suggests that body temperature is not affected by a patient's age.

[A Case of Surgical Resection of Hepatic Leiomyosarcoma].

A 72-year-old woman was referred to our hospital due to an abdominal mass. Ultrasound sonography and computed tomography revealed liver tumors in liver segments 2 and 3. The preoperative diagnosis was hepatocellular carcinoma. The patient underwent an extended left lobectomy. Histological examination of resected specimens revealed that the tumors were hepatic leiomyosarcoma. We report our experience of this hepatic leiomyosarcoma, along with the literature on this tumor type.

[A Case of Pancreatic Cancer Associated with Autoimmune Pancreatitis].

A 74-year-old man with IgG4-related cholangitis had been treated with steroids for 1 year. In the outpatient clinic, elevated levels of the tumor marker CA19-9 and serum IgG4 were observed. Abdominal enhanced CT showed a 20mm hypovascular tumor in the pancreatic head. ERCP showed narrowingof the main pancreatic duct in the pancreatic head with slight caudal dilation and stricture of the lower common bile duct. We made a diagnosis of pancreatic cancer, and the patient underwent pancreaticoduodenectomy. Pathological examination of the resected tissue revealed a well-differentiated adenocarcinoma surrounded by autoimmune pancreatitis, characteristic of lymphoplasmacytic sclerosingpancreatitis. He is receiving adjuvant chemotherapy with S-1 in the outpatient clinic.

[Safety and Feasibility of Pancreatic Surgery for Pancreatic Cancer in Elderly Patients].

PURPOSE: This study aimed to evaluate the safety and feasibility of pancreatic surgery for pancreatic cancer in elderly patients. PATIENTS AND METHODS: In total, 9 patients underwent pancreatic surgery for pancreatic cancer between April 2005 and March 2014. The surgical complications were evaluated by Clavien-Dindo classification. RESULTS: The median operating time was 420(range: 354-503)min and the median blood loss was 640(range: 350-1,170)mL. Grade 2 or higher complications were observed in 3 patients. Pancreatic fistula(Grade 3b)was observed in 1 patient, delirium was observed(Grade 2)in 1 patient, and portal vein thrombosis(Grade 2)was observed in 1 patient. No surgical mortality was observed. DISCUSSION: Our results suggest that pancreatic surgery is a safe and feasible treatment for pancreatic cancer in elderly patients.

[A Case of Primary Splenic Inflammatory Myofibroblastic Tumor].

Inflammatory myofibroblastic tumor(IMT)is a rare neoplasm. IMTs are found in a number of locations throughout the body, but splenic involvement is uncommon. One case of splenic IMT is described. A 42-year-old woman presented with anterior chest pain and was found to have a splenic mass by computed tomography(CT). Fluorine-18-FDG-PET showed no FDG accumulation in the spleen. Magnetic resonance imaging(MRI)at 6 months follow-up showed an increase in the size of the tumor. We performed splenectomy for a suspected malignant tumor. The surgical specimen was a gray-white mass in the spleen. The mass was histopathologically diagnosed as primary splenic IMT because it consisted of desmin- and SMA-positive spindle-shaped cells with various inflammatory cells. In Japan, only 6 cases(including this case)of primary splenic IMT have been reported. Surgery is the only curative approach, but recurrences occur in around 5% of cases of pulmonary IMT, and around 25% of cases of extrapulmonary IMT. This patient needs to be carefully followed up.

[A Case of Primary Liposarcoma Arising from the Duodenum].

We report a case of duodenal liposarcoma. A 62-year-old man presented with an abdominal tumor. Abdominal CT scan and MRI showed a tumor in the wall of the duodenum. Pancreaticoduodenectomy was performed. The final pathological diagnosis was mixed-type liposarcoma. Twenty-one months after the 1st surgery, the patient presented with locoregional recurrence and tumor resection was performed. However, 12 months after the 2nd operation, the patient again presented with locoregional recurrence and further surgery is planned.

Clinical implication of peritoneal cytology in the pancreatic cancer patients who underwent curative resection followed by adjuvant gemcitabine or S-1 chemotherapy.

BACKGROUND/AIMS: The clinical implications of peritoneal lavage cytology (CY) status in the patients who received curative resection and adjuvant chemotherapy have not been established. METHODOLOGY: We retrospectively analyzed clinical data from 143 consecutive patients who underwent macroscopically curative resection and received adjuvant gemcitabine or S-1 chemotherapy for pancreatic cancer from 2005 to 2014 in our institution. Correlations between CY status and survival and clinicopathological features were investigated. RESULTS: Of the 143 patients, 21 patients were peritoneal washing cytology positive (CY+) (14.7%). Although significant difference was observed in the tumor size, no other correlation between cytology status and clinicopathological parameter existed. The recurrence free survival (RFS) rates at 3 and 5 years after surgery were 5.1% and 0% in CY+ patients, respectively, and were 21.5% and 16.1% in peritoneal washing cytology negative (CY-) patients, respectively, which were significantly different (p=0.001). The OS rates at 3 and 5 years after surgery were 17.1% and 8.6% in CY+ patients, respectively, and were 26.1% and 16.1% in CY- patients, respectively, which were trend to worse in the CY+ patients (p=0.254). CONCLUSION: The patients with CY+ are likely to experience recurrence, even after they received curative resection and adjuvant Gemcitabine or S-1 adjuvant chemotherapy.

Lymphatic invasion is an independent prognostic factor in pancreatic cancer patients undergoing curative resection followed by adjuvant chemotherapy with gemcitabine or S-1.

BACKGROUND/AIMS: The objective of this retrospective study was to clarify prognostic factors in pancreatic cancer patients undergoing curative resection followed by adjuvant chemotherapy with gemcitabine or S-1. METHODOLOGY: Both overall survival (OS) and recurrence-free survival (RFS) were examined in 122 pancreatic cancer patients who underwent curative surgery and received adjuvant gemcitabine or S-1 after surgery between 2005 and 2014. RESULTS: When the length of OS was evaluated according to the log-rank test, significant differences were observed in lymphatic invasion and the T status. Univariate and multivariate Cox's proportional hazard analyses demonstrated that lymphatic invasion was the only significant independent prognostic factor for both OS and RFS. The 5-year OS was 30.1% in the lymphatic invasion-negative group and 12.1% in the lymphatic invasion-positive group (p < 0.001). Moreover, the 5-year RFS was 20.5% in the lymphatic invasion-negative group and 10.4% in the lymphatic invasion- positive group (p = 0.006). CONCLUSIONS: Lymphatic invasion is the most important prognostic factor for OS and RFS in patients with pancreatic cancer who undergo curative resection followed by adjuvant chemotherapy. The present results suggest that adjuvant chemotherapy is not sufficient, especially in patients with risk factors. Such patients should be evaluated as a target group for clinical trials of novel treatments.

The short- and long-term outcomes of radical antegrade modular pancreatosplenectomy for adenocarcinoma of the body and tail of the pancreas.

BACKGROUND: Radical antegrade modular pancreatosplenectomy (RAMPS) is a relatively new modification of the standard distal pancreatosplenectomy. In this method, dissection proceeds from right-to-left to achieve negative posterior resection margins. However, short-term and long-term outcomes of RAMPS for pancreatic cancer have not yet been clarified. The aim of this study is to evaluate short-term and long-term outcomes in the patients who have undergone RAMPS. METHODS: Consecutive 49 patients were selected from the retrospective database of the Kanagawa Cancer Center from 2000 to 2014. Data from the operative notes, pathology reports, postoperative data, and outpatient data (recurrence and survival) were entered into the database. RESULTS: All patients were undergone anterior RAMPS. The median operation time was 278 min (range from 140 to 625 mins). The median blood loss in operation was 850 ml (range from 60 to 2790 ml). The overall incidence of morbidity was 51.4% and the incidence of mortality was 0%. Forty-one patients (83.7%) had negative resection margins. The mean number of lymph nodes harvested was 15 and 27 patients had lymph node metastasis. After the median follow-up period was 41.1 months, 1-year and 3-year overall survival rates were 84.1 and 38.6%, respectively. Median overall survival was 22.6 months. CONCLUSIONS: The present study results suggested that RAMPS procedure might be safe and feasible without an increase in morbidity and morbidity and have survival benefit compared with standard DP.

[The Safety and Feasibility of Conversion Surgery for Initially Unresectable Pancreatic Cancer].

BACKGROUND: By remarkable progress of chemotherapy for pancreatic cancer, we sometimes achieve resection of initially unresectable pancreatic cancer after chemotherapy. Otherwise, the safety and feasibility of radical pancreatic resection after chemotherapy is not still clear. In this report, we evaluated the safety and feasibility of conversion surgery for initially unresectable pancreatic cancer in our center. PATIENTS AND METHODS: Between 2009 and 2014, approximately 500 patients were diagnosed with unresectable pancreatic cancer and received chemotherapy, and after chemotherapy, 10 patients were found to have resectable tumors on computed tomography. We evaluated surgical complications using the Clavien-Dindo classification. Clinicopathological data were reviewed by using UICC, seventh edition, and the chemotherapeutic effect was measured by using Evans classification. RESULTS: The mean age of patients was 68 years, with 4 men and 6 women. The preoperative chemotherapy regimens were S-1 chemotherapy in 2 patients, gemcitabine in 5 patients, and gemcitabine plus S-1 chemotherapy in 3 patients. Nine patients underwent pancreatoduodenectomy, and 1 underwent distal pancreatosplenectomy. The mean operative time was 527.5 minutes, and the mean estimated blood loss was 875 mL. Surgery-related morbidity more than Grade 2 based on Clavien-Dindo classification occurred in 6 patients. Mortality was 0%. CONCLUSION: Our study suggests that conversion surgery for initially unresectable pancreatic cancer is safe and feasible.

[A Case of Undifferentiated Carcinoma of the Gallbladder].

In this paper, we present a case of undifferentiated carcinoma of the gallbladder, which is a rare disease with poor prognosis. A 77-year-old woman presented with right hypochondralgia. An abdominal CT scan showed a tumor more than 80 mm in diameter invading the liver parenchyma and transverse colon, and showed liver and lymph node metastases. We diagnosed the patient with stage Ⅳ carcinoma of the gallbladder. We resected the gallbladder, S4a plus S5 of the liver, part of the transverse colon, the lymph nodes, the greater omentum, and the extra hepatic bile duct; biliary reconstruction was then performed. Histological examination showed that most areas consisted of undifferentiated cells. The diagnosis of undifferentiated carcinoma was made according to the WHO classification of tumors of the digestive system. No recurrence has been detected for 1 year.

[Safety and Feasibility of the Bioabsorbable Staple Line Reinforcement in Distal Pancreatic Resections].

PURPOSE: The aim of this study was to evaluate the safety and feasibility of the bioabsorbable staple line reinforcement in distal pancreatic resection. PATIENTS & METHODS: Thirteen patients underwent distal pancreatic resection using the bioabsorbable staple line reinforcement between May 2014 and December 2014. Surgical complications were evaluated by Clavien-Dindo classification. RESULT: Median age was 64 years. Median operation time was 219 minutes and median blood loss was 490 mL. Complications>Grade 2 were observed in 3 patients. Among them, pancreatic fistula (Grade 2) was found in 2 patients and ileus (Grade 2) in 1. No surgical mortality was observed. DISCUSSION: Our results may suggest that the bioabsorbable staple line reinforcement is safe and feasible in distal pancreatic resection.

The clinical impacts of the prognostic nutritional index for the esophageal cancer patients who received curative treatment.

BACKGROUND: We investigated the impact of the prognostic nutritional index (PNI) on esophageal cancer survival and recurrence after curative treatment. METHODS: This study included 120 patients who underwent curative surgery followed by the adjuvant treatment for esophageal cancer between 2008 and 2018. The risk factors for overall survival (OS) and recurrence-free survival (RFS) were identified. RESULTS: The PNI of 49 was regarded to be the optimal critical point of classification considering the 1-year, 3-year, and 5-year survival rate. The OS rates at three and five years after surgery were 47.4% and 36.0% in the PNI low group, respectively, and 62.5% and 56.5% in the PNI high group, which amounted to a statistically significant difference ( P = 0.020). The RFS rates at three and five years after surgery were 31.0% and 24.8% in the PNI low group, respectively, and 50.9% and 42.8% in the PNI high group, which amounted to a statistically significant difference ( P = 0.020). A multivariate analysis demonstrated that the PNI was a significant independent risk factor for the OS and a marginally significant independent risk factor forRFS. CONCLUSION: The PNI was a risk factor for survival in patients who underwent curative treatment for esophageal cancer. It is necessary to develop the effective plan of the perioperative care and the surgical strategy according to the PNI.

Clinical Impact of Preoperative Prognostic Nutritional Index in Surgical Patients With Pancreatic Cancer Treated With Perioperative Adjuvant Chemotherapy.

BACKGROUND/AIM: The prognostic nutritional index (PNI) is used as a marker to evaluate the nutritional and immunological status of patients with various cancers. This study aimed to investigate whether preoperative PNI is a prognostic factor in patients with pancreatic cancer who underwent perioperative adjuvant chemotherapy and surgical resection. PATIENTS AND METHODS: We retrospectively enrolled 232 pancreatic cancer patients who underwent surgical resection with perioperative adjuvant chemotherapy between January 2013 and December 2022. Overall survival (OS) and relapse-free survival (RFS) rates were calculated using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazards regression models. RESULTS: The optimal cutoff value for the preoperative PNI was 44.3 in the present study. PNI <44.3 was associated with older age (p<0.001) and affected the clinical course of postoperative adjuvant chemotherapy. The PNI <44.3 had an important influence on the decreased OS (25.1 vs. 39.0 months) and RFS (13.1 vs. 22.8 months). In univariate and multivariate analyses, the preoperative PNI was an independent prognostic factor for OS [hazard ratio (HR)=1.682, 95% confidence interval (CI)=1.059-2.673, p=0.028] and RFS (HR=1.559, 95% CI=1.037-2.344, p=0.033). CONCLUSION: Preoperative PNI is a prognostic factor for both OS and RFS in patients with pancreatic cancer who underwent perioperative adjuvant chemotherapy and surgical resection. This study suggests that a low PNI may cause a lack of full-dose adjuvant chemotherapy, leading to recurrence and resulting in a poor prognosis for surgical pancreatic cancer patients treated with perioperative adjuvant chemotherapy.

Non-invasive intraductal oncocytic papillary neoplasm forming a protruding lesion toward the duodenum from the accessory papilla: a case report.

BACKGROUND: Intraductal oncocytic papillary neoplasm (IOPN), previously classified as a subtype of intraductal papillary mucinous neoplasm (IPMN), has been described as an independent disease by the WHO since 2019. IOPN is a rare tumor, with few reported cases. Herein, we report a case of resected non-invasive IOPN that formed a lesion protruding toward the duodenum from the accessory papilla. CASE PRESENTATION: An 80-year-old woman was referred to our hospital because of a giant mass in the pancreatic head detected on abdominal contrast-enhanced computed tomography (CT) performed for a close examination of a mass in the right breast. CT revealed a 90-mm-sized tumor with a mixture of solid and cystic components, with contrast enhancement in the pancreatic head, and a dilated main pancreatic duct. Esophagogastroduodenoscopy revealed a semi-circumferential papillary tumor protruding toward the duodenal lumen, which did not protrude from the papilla of Vater. Transpapillary biopsy led to a preoperative diagnosis of IPMN with an associated invasive carcinoma. As there were no distant metastasis, open subtotal stomach-preserving pancreaticoduodenectomy was performed. Analysis of the surgical specimen and histopathological examination revealed that the tumor was an IOPN that protruded toward the duodenal mucosa from the accessory papilla while replacing the duodenal mucosa with no obvious stromal invasion. CONCLUSION: IOPN is a rare and poorly recognized tumor with few reported cases. There have been no reports describing IOPN forming a protruding lesion toward the duodenum from the accessory papilla. Therefore, further accumulation of cases such as this one is important to advance the study of IOPN.

Clinical Impact of Preoperative Neutrophil-to-Lymphocyte Ratio in Surgical Patients With Pancreatic Cancer.

BACKGROUND/AIM: The prognosis of patients with pancreatic cancer remains poor, despite recent advances in surgical techniques, perioperative care, neoadjuvant and adjuvant chemotherapy. This study aimed to investigate the preoperative neutrophil-to-lymphocyte ratio (NLR) as a prognostic factor and determine the optimal cutoff value in surgical patients with pancreatic cancer. PATIENTS AND METHODS: We retrospectively enrolled 461 patients with pancreatic cancer who underwent resection between January 2013 and December 2022 in the Department of Gastrointestinal Surgery at Kanagawa Cancer Center. The association between continuous or categorical variables and NLR was analyzed using the Mann-Whitney U-test and Fisher's exact test. Overall survival (OS) and relapse-free survival (RFS) rates were calculated using the Kaplan-Meier method. Univariate and multivariate analyses were performed using Cox proportional-hazard regression models. RESULTS: The optimal cutoff value for the preoperative NLR was 3.2. The NLR≥3.2 was associated with a large tumor size (p=0.005), poor histological differentiation (p=0.002), and less adjuvant chemotherapy (p=0.048). The NLR≥3.2 had an important influence on the decreased OS (21.6 vs. 25.8 months), and RFS (10.3 vs. 14.3 months). In univariate and multivariate analyses, the preoperative NLR was an independent prognostic factor for OS (p=0.022) and RFS (p=0.002). CONCLUSION: Preoperative NLR (cutoff value: 3.2) within two weeks before surgery is a prognostic factor for OS and RFS in surgical patients with pancreatic cancer. This study could help establish evidence on the immune system's impact and a unified treatment strategy pre-surgery, potentially improving the prognosis for patients with pancreatic cancer.

Carbon Ion Radiotherapy Versus Perioperative Adjuvant Chemotherapy and Curative Surgery for Resectable Pancreatic Cancer.

BACKGROUND/AIM: The standard treatment for resectable pancreatic cancer is preoperative adjuvant chemotherapy (NAC) + curative surgery + adjuvant chemotherapy. Although excellent local control results of carbon ion radiotherapy (CIRT) for pancreatic cancer have been reported, no reports have compared CIRT with the standard treatment for resectable pancreatic cancer. In this study, we compared the results of CIRT for resectable pancreatic cancer with those of standard therapy and investigated the usefulness of CIRT. PATIENTS AND METHODS: The subjects were 35 patients who underwent CIRT for clinical cT1-2, N0-1, and M0 cancers at Kanagawa Cancer Center, Yokohama, Japan, from September 2018 to September 2021, and 110 patients who underwent standard treatment (NAC + curative surgery + adjuvant). Overall survival (OS) and recurrence-free survival (PFS) were compared between the two groups using propensity score-matching (PSM). RESULTS: Twenty-three CIRT monotherapy patients were matched with NAC + curative surgery + adjuvant chemotherapy patients by PSM. Although there was no significant difference in RFS between the two groups, OS was significantly poorer in the CIRT monotherapy group than in the NAC + curative surgery + adjuvant chemotherapy group. CONCLUSION: This single-centre retrospective propensity score-matched comparison of CIRT and NAC + curative resection + adjuvant chemotherapy as the standard therapy for resectable pancreatic cancer showed an inferiority of CIRT in terms of OS, but no difference in PFS. Therefore, CIRT monotherapy may be a treatment strategy for patients with contraindications for standard treatment of curative surgery plus perioperative chemotherapy.