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Purpose: Cholelithiasis occurs often after gastrectomy. However, no consensus has been established regarding the difference in the incidence of postgastrectomy cholelithiasis with different reconstruction methods. In this study, we examined the frequency of cholelithiasis after two major reconstruction methods, namely Billroth-I (B-I) and Roux-en-Y (R-Y) following laparoscopic distal gastrectomy (LDG) for gastric cancer., Methods: Among 696 gastric cancer patients who underwent LDG between April 2000 and March 2017, after applying the exclusion criteria, 284 patients who underwent B-I and 310 who underwent R-Y were examined retrospectively. The estimated incidence of cholelithiasis was compared between the methods, and factors associated with the development of cholelithiasis in the gallbladder and/or common bile duct were investigated., Results: During the median follow-up of 61.2 months, 52 patients (8.8%) developed cholelithiasis postgastrectomy; 12 patients (4.2%) after B-I and 40 (12.9%) after R-Y (p = 0.0002). Among them, choledocholithiasis was more frequent in patients who underwent R-Y (n = 11, 27.5%) vs. B-I (n = 1, 8.3%) (p = 0.0056). Univariate and multivariate analyses revealed that male sex, body mass index > 22.5 kg/m 2 , and R-Y reconstruction were significant predictors of the development of postLDG cholelithiasis., Conclusion: Regarding cholelithiasis development, B-I reconstruction should be preferred whenever possible during distal gastrectomy., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Subcutaneous emphysema (SE) is a complication of laparoscopic surgery, potentially resulting in severe respiratory failure. No reports to date have focused on SE during robot-assisted (RA) rectal surgery. We aimed to reveal the risk factors and clinical significance of SE after RA/laparoscopic rectal surgery. We retrospectively reviewed 221 consecutive patients who underwent RA/laparoscopic rectal surgery. The occurrence of SE was evaluated on postoperative radiographs. Laparoscopic surgery was performed in 120 patients and RA in 101. SE developed in 55 (24.9%) patients. Logistic regression analysis identified RA surgery (odds ratio [OR]: 4.89, 95% confidence interval [CI] 2.13-11.22, p < 0.001), higher age (OR: 1.06, 95% CI 1.03-1.11, p < 0.001), lower body mass index (BMI) (OR: 0.79, 95% CI 0.67-0.93, p = 0.004), thinner subcutaneous layer (OR: 0.88, 95% CI 0.79-0.98, p = 0.02), and lateral lymph node dissection (OR: 9.43, 95% CI 2.44-36.42, p < 0.001) as risk factors for SE. Maximum end-tidal CO 2 was significantly higher in the SE than the non-SE cohort (p < 0.001). There was no difference in postoperative complication rate or length of hospital stay. Lower BMI (OR: 0.79, 95% CI 0.62-0.97, p = 0.02) and thinner subcutaneous layer (OR: 0.84, 95% CI 0.71-0.97, p = 0.01) were predictive factors in the RA cohort. SE occurs more frequently in RA compared with laparoscopic surgery. SE has a modest impact on short-term outcomes, but may occasionally cause severe problems. The indication of RA surgery should be considered carefully in high-risk elderly patients., (© 2024. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

Pancreatic cancer is one of the most adverse diseases and it is very difficult to treat because the cancer cells formed in the pancreas intertwine themselves with nearby blood vessels and connective tissue. Hence, the surgical procedure of treatment becomes complicated and it does not always lead to a cure. Histopathological diagnosis is the usual approach for cancer diagnosis. However, the pancreas remains so deep inside the body that experts sometimes struggle to detect cancer in it. Computer-aided diagnosis can come to the aid of pathologists in this scenario. It assists experts by supporting their diagnostic decisions. In this research, we carried out a deep learning-based approach to analyze histopathology images. We collected whole-slide images of KPC mice to implement this work. The pancreatic abnormalities observed in KPC mice develop similar histological features to human beings. We created random patches from whole-slide images. Then, a convolutional autoencoder framework was used to embed these patches into an integrated latent space. We applied 'information maximization', a deep learning clustering technique to cluster the identical patches in an unsupervised manner since our dataset does not have annotation. Moreover, Uniform manifold approximation and projection, a nonlinear dimension reduction technique was utilized to visualize the embedded patches in a 2-dimensional space. Finally, we calculated a few internal cluster validation metrics to determine the optimal cluster set. Our work concentrated on patch-based anomaly detection in the whole slide histopathology images of KPC mice., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Rumman et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: In telementoring, differences in teaching methods affect local surgeons' comprehension. Because the object to be operated on is a three-dimensional (3D) structure, voice or 2D annotation may not be sufficient to convey the instructor's intention. In this study, we examined the usefulness of telementoring using 3D drawing annotations in robotic surgery., Methods: Kyushu University and Beppu Hospital are located 140 km apart, and the study was conducted using a Saroa™ surgical robot by RIVERFIELD Inc. using a commercial guarantee network on optical fiber. Twenty medical students performed vertical mattress suturing using a swine intestinal tract under surgical guidance at the Center for Advanced Medical Innovation Kyushu University. Surgical guidance was provided by Beppu Hospital using voice, 2D, and 3D drawing annotations. All robot operations were performed using 3D images, and only the annotations were independently switched between voice and 2D and 3D images. The operation time, needle movement, and performance were also evaluated., Results: The 3D annotation group tended to have a shorter working time than the control group (25.6 ± 63.2 vs. - 36.7 ± 65.4 min, P = 0.06). The 3D annotation group had fewer retries than the control group (1.3 ± 1.7 vs. - 1.1 ± 0.7, P = 0.006), and there was a tendency for fewer needle drops (0.4 ± 0.7 vs. - 0.5 ± 0.9, P = 0.06). The 3D annotation group scored significantly higher than the control group on the Global Evaluate Assessment of Robot Skills (16.8 ± 2.0 vs. 22.8 ± 2.4, P = 0.04). The 3D annotation group also scored higher than the voice (13.4 ± 1.2) and 2D annotation (16.2 ± 1.8) groups (3D vs. voice: P = 0.03, 3D vs. 2D: P = 0.03)., Conclusion: Telementoring using 3D drawing annotation was shown to provide good comprehension and a smooth operation for local surgeons., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: There are several options for the treatment of gastrointestinal stricture, including endoscopic stent placement and bypass surgery. However, a benign stricture is difficult to manage in a reconstructed gastric tube in the thoracic cavity owing to the technical difficulty of bypass surgery, and the possibility of stent migration., Case Presentation: A 78-year-old woman was admitted to our hospital for treatment for her inability to eat. She had undergone video-assisted subtotal esophagectomy with retromediastinal gastric tube reconstruction 7 years earlier. At the current admission, there was a severely dilated gastric tube in the thoracic cavity with a soft stricture immediately anterior to the spine. Conservative therapy was ineffective; therefore, endoscopic stenting was performed. However, the stent migrated to the upper side of the stricture because the stricture was mild, and the stent was not fixed in the gastric tube. Next, endoscopic stent placement followed by laparoscopic stent fixation was performed. The stent was patent and worked well, and the patient's body weight increased. However, the stent collapsed 2 years later, with recurrence of symptoms. Stent-in-stent placement with an over-the-scope clip was performed, and the second stent was also patent and worked well., Conclusions: Laparoscopic stent fixation with endoscopic stent placement could be an effective option for patients with a benign stricture in the reconstructed gastric tube., (© 2023. The Author(s).)

Background/aim: Family history of colorectal cancer (CRC) is a known risk factor for CRC. However, its prognostic value in patients with CRC remains controversial. This study aimed to clarify the prognostic impact of a family history of CRC., Patients and Methods: We retrospectively reviewed the database from 1978 to 2018 and enrolled 3,655 consecutive patients with CRC. We investigated the clinicopathological factors of patients with CRC with and without a family history. After propensity score matching, we performed a survival analysis of patients with CRC with and without a family history., Results: Patients with CRC with a family history of CRC had a young onset (63.2 and 65.9; p<0.001), were more likely to be female (54.3% and 49.7%; p=0.042), had less symptomatic disease (76.9% and 80.8%; p=0.008), were more likely to have right-sided colon cancer (27.5% and 26.1%), and had less distant metastases (11.3% and 14.9%; p=0.023) and multiple CRCs (10.2% and 7.8%) compared with those without a family history of CRC. Prior to propensity score matching, CRC-specific survival analysis showed that a family history of CRC was a good prognostic factor (p=0.022). After propensity score matching, survival curves overlapped between the two groups., Conclusion: Patients with CRC with a family history of CRC had specific clinicopathological features including younger onset, female sex, proximal colon location, fewer symptoms, smaller number of distant metastases, likelihood of multiple diseases, and earlier cancer stage. Family history of CRC in patients with CRC was not a prognostic factor., (Copyright © 2023 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background: Although radical antegrade modular pancreatosplenectomy for pancreatic ductal adenocarcinoma (PDAC) has become the gold standard procedure in open distal pancreatectomy, there has been no gold standardized procedure for PDAC in minimally invasive distal pancreatectomy (MIDP). In this study, we analyzed our novel cranial-to-caudal approach (CC approach) for patients undergoing MIDP and provide a video clip illustrating the details of the CC approach., Methods: Ninety-four patients who underwent MIDP with splenectomy between 2016 and 2021 were included in this study. The CC approach was performed in 23 (24.5%) of the 94 patients. The concept of the CC approach is easy identification of Gerota's fascia from the cranial side of the pancreas and secure tumor removal (R0 resection) wrapped by Gerota's fascia. The short- and long-term outcomes were compared between the CC and non-CC approaches., Results: The median operation time and blood loss were similar between the two groups. The ratios of grade ≥ B postoperative pancreatic fistula and Clavien-Dindo grade ≥ III complications were also comparable. All patients in the CC approach group achieved R0 resection, and the R0 ratio was similar in the two groups (p = 0.345). The 2-year survival rate in CC and non-CC approach groups was 87.5% and 83.6%, respectively (p = 0.903)., Conclusions: The details of the CC approach for MIDP were demonstrated based on an anatomical point of view. This approach has the potential to become a standardized approach for left-sided PDAC., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Pagetoid spread (PS) of anorectal cancer is relatively rare and associated with poor prognosis. While a primary tumorous lesion is usually obvious in most PS cases, we experienced two cases of nonmass-forming type anorectal cancer with PS. It remains challenging to decide strategies. In both cases, histological findings of a perianal skin biopsy showed proliferation of atypical cells that were positive for cytokeratin (CK) 7, CK20, and caudal type homeobox 2 and negative for Gross cystic disease fluid protein 15, suggesting PS. Abdominoperineal resection (APR) with extensive anal skin resection was performed in both patients. The pathological diagnosis in each was nonmass-forming type anorectal cancer with PS. Neither has experienced recurrence in postoperative courses. Even nonmass-forming type anorectal cancer with PS could have high malignant potentials. APR with lymph nodes dissection and wide skin excision and regular surveillance might be necessary., (© 2023 Asia Endosurgery Task Force and Japan Society of Endoscopic Surgery and John Wiley & Sons Australia, Ltd.)

Background: Tertiary lymphoid structures (TLSs) are associated with a favorable prognosis in several cancers. However, the correlation between TLSs and outcomes of esophageal squamous cell carcinoma (ESCC) and the impact of TLSs on the tumor immune microenvironment (TIME) remain unknown., Methods: We pathologically evaluated the significance of TLSs in ESCC focusing on TLS maturation using 180 ESCC specimens and performed single-cell RNA sequencing (scRNA-seq) using 14 ESCC tissues to investigate functional differences of immune cells according to TLS presence., Results: TLS+ cases had better recurrence-free-survival (RFS) (p < 0.0001) and overall survival (OS) (p = 0.0016) compared with TLS- cases. Additionally, mature TLS+ cases had better RFS and OS compared with immature TLS+ cases (p = 0.019 and p = 0.015) and TLS- cases (p < 0.0001 and p = 0.0002). The scRNA-seq showed that CD8 + T cells in TLS+ tumors expressed high levels of cytotoxic signatures and antigen-presentation of dendritic cells (DCs) was enhanced in TLS+ tumors. Immunohistochemistry showed that the densities of tumor-infiltrating CD8 + T cells and DCs were significantly higher in TLS+ tumors than those in TLS- tumors., Conclusions: These data suggest the prognostic and functional significance of TLSs in ESCC and provides new insights into TLSs on the TIME., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Cancer incidence is increasing annually, and the invasion of cancer into the stroma significantly affects cancer metastasis. The stroma primarily comprises an abundant extracellular matrix (ECM) that interacts closely with cancer cells. Cancer cells use the ECM as a scaffold to migrate from a tumor via mechanical actions such as pushing and pulling the fibers. The purpose of this study is to clarify the effects of elastic modulus differences on cell migration behavior based on the same ECM fiber structure. We observe temporal changes in the morphology of cancer cells and the surrounding ECM to elucidate the relationship between changes in the mechanical properties of the ECM and the invasive behavior of cancer cells. We analyze the shape and migration distance of cancer cells and the displacement field of the ECM by varying the fiber elastic modulus but fixing the ECM density. Increasing the elastic modulus results in a protruding cell shape, which indicates the maximum displacement of the ECM around the cell. Additionally, differences in cell migration speed and dispersion based on the elastic modulus are observed. The behavior of cells with increasing elasticity is classified via cluster analysis. Owing to the chemical cross-linking of the fibers, some cells cannot deform the surrounding tissue. This is attributable to the gel state of the ECM and microscopic fluctuations in the fiber density around the cells. We successfully assessed the effect of changes in the ECM modulus on cell mortality and morphology to reveal the mechanism of cancer invasion., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Intratumor bacteria modify the tumor immune microenvironment and influence outcomes of various tumors. Periodontal pathogen Fusobacterium nucleatum has been detected in pancreatic cancer tissues and is associated with poor prognosis. However, it remains unclear how F. nucleatum affects pancreatic cancer. Here, we compared clinical features with F. nucleatum colonization in pancreatic cancer tissues. F. nucleatum was detected in 15.5% (13/84) of pancreatic cancer patients. The tumor size was significantly larger in the F. nucleatum-positive group than in the negative group. To clarify the biological effect of intratumor F. nucleatum on pancreatic cancer progression, we performed migration/invasion assays and cytokine array analysis of cancer cells cocultured with F. nucleatum. F. nucleatum promoted CXCL1 secretion from pancreatic cancer cells, leading to cancer progression through autocrine signaling. Intratumor F. nucleatum suppressed tumor-infiltrating CD8 + T cells by recruiting myeloid-derived suppressor cells (MDSCs) to the tumor in an F. nucleatum-injected subcutaneous pancreatic cancer mouse model, resulting in tumor progression. Furthermore, tumor growth accelerated by F. nucleatum was suppressed by MDSC depletion or cytokine inhibitors. Intratumor F. nucleatum promoted pancreatic cancer progression through autocrine and paracrine mechanisms of the CXCL1-CXCR2 axis. Blockade of the CXCL1-CXCR2 axis may be a novel therapeutic approach for patients with intratumor F. nucleatum-positive pancreatic cancer., (© 2023 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Background: Malnutrition impacts the clinical course of Crohn's disease; however, there is little evidence of its influence on perioperative adverse events. We assessed whether nutritional indicators are associated with postoperative complications in surgical treatment of Crohn's disease., Methods: 137 patients with Crohn's disease who underwent surgical treatment between January 2011 and December 2020 were included. Skeletal muscle index was calculated by a single CT slice. We analyzed the risk factors for adverse events., Results: 37 % of patients had postoperative complications. Adverse events occurred more frequently in patients with high serum C-reactive protein, low serum albumin, prognostic nutritional index <38.3, skeletal muscle index <38.9 cm 2 /m 2 , abdominoperineal resection, long surgical duration, and mass hemorrhage. Among patients with skeletal muscle index <38.9 cm 2 /m 2 , patients who experienced adverse events had higher visceral fat index compared with those who did not (0.85 vs. 0.45, P  = 0.04). Multivariate analysis revealed that skeletal muscle index <38.9 cm 2 /m 2 and low serum albumin were the independent risk factors for postoperative complications (Odds ratio, 2.85; 95 % confidence interval, 1.13-7.16; P  = 0.03, 2.62; 1.09-6.26; P  = 0.03, respectively). Separated by sex, low serum albumin (<3.5 and <2.8 g/dL, male and female, respectively) and skeletal muscle index (<38.9 and <36.6 cm 2 /m 2 , male and female, respectively) were statistically related to postoperative complications., Conclusions: Skeletal muscle index is the most useful nutritional predictor of postoperative complications in Crohn's disease patients among other nutritional indices. We believe that these patients are at high risk of postoperative complications and need appropriate nutritional support in the perioperative period., Competing Interests: The authors have declared no conflicts of interest., (© 2023 The Authors.)

Purpose: This study aimed to demonstrate the involvement of angiogenesis in cancer-associated acinar-to-ductal metaplasia (CA-ADM) lesion of invasive front pancreatic ductal adenocarcinoma (PDAC) and investigate the possible mechanism., Methods: Tissue samples from 128 patients with PDAC and 36 LSL-Kras G12D/+ ; LSL-Trp53 R172H/+ ; Pdx-1-Cre mice were analyzed. Immunohistochemical assay was performed using HE, anti-CK19 and anti-amylase to confirm the presence of CA-ADM lesions, using anti-CD34 and anti-CD31 to measure microvessel density (MVD), and using anti-CD68, anti-CD163, anti-iNOS, or anti-MMP9 to evaluate the immune microenvironment. We performed multiplex immunohistochemical assay to detect the co-expression of MMP9 and CD68 on macrophage. We examined clinical outcomes and other clinicopathological factors to determine the significance of high-level MVD of CA-ADM on survival and liver metastasis. We performed tube formation assay to evaluate the effect of macrophage on angiogenic capacity in vitro., Results: Angiogenesis was significantly abundant in CA-ADM lesions compared with that in PDAC lesions in human and mouse tissues. High-level MVD in CA-ADM lesions was an independent predictor of poor prognosis (P = 0.0047) and the recurrence of liver metastasis (P = 0.0027). More CD68-positive and CD163-positive macrophages were detected in CA-ADM lesions than in PDAC. The percentage of CD68-positive macrophages was positively correlated with MVD in CA-ADM lesions. Multiplex-immunostaining revealed that MMP9 was expressed in CD68-positive macrophages of CA-ADM lesions. In CA-ADM lesions, the percentage of macrophages was positively correlated with MMP9 expression, which positively correlated with microvessel density., Conclusion: CA-ADM related angiogenesis is a promising predictive marker for poor prognosis of PDAC and may provide an attractive therapeutic target for PDAC., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: This study evaluated the reliability, validity, and responsiveness of the Japanese version of the European Organization for Research and Treatment of Cancer (EORTC) QLQ-ELD14 and measured the health-related quality of life (HRQOL) of elderly Japanese patients with cancer aged ≥ 60 and ≥ 70 years., Methods: The study recruited elderly Japanese patients with cancer aged ≥ 60 (≥ 70) years (n = 1803 [n = 1236]). The EORTC QLQ-ELD14 was evaluated for reliability, validity, responsiveness, and correlations of changes in score between the EORTC QLQ-ELD14 and the EORTC QLQ-C30 before and after the commencement of the COVID-19 pandemic., Results: In both age groups, the proportion of missing items was low (< 3%). Cronbach's α was good at ≥ 0.70, except for two of the seven items. All the intraclass coefficient constants were good at ≥ 0.70. The concurrent validity was good but correlation with the EORTC QLQ-C30 was not strong, except for the hypothesis items. Regarding the assessment of responsiveness, only one item ("maintaining purpose") of the EORTC QLQ-ELD14 worsened (- 6.14 ± 29.20, standard response of mean > 0.2) after the commencement of the COVID-19 pandemic. The changes in score between the EORTC QLQ-ELD14 and the "global health status/QOL" and "summary score" of the EORTC QLQ-C30 had moderate-to-high negative correlations for all items, except two. Hypotheses to evaluate construct validity were accepted at 90%, while responsiveness was accepted at 80%., Conclusion: The Japanese version of the EORTC QLQ-ELD14 questionnaire appears to have acceptable reliability, validity, and responsiveness to evaluate HRQOL in elderly Japanese people with cancer., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: In recent years, the number of minimally invasive pancreatoduodenectomy (MIPD) has been increasing; however, the procedure has not been widely accepted due to its complexity and difficulty. We have developed a technique to mobilize the pancreas head using a left-sided approach with a focus on the complete dissection of the Treitz ligament., Methods: This technique focuses on the secure mobilization of the pancreas head using a left-sided approach. First, the transverse mesocolon is flipped upward and the anterior side of the mesojejunum is excised to expose the first jejunal artery (1st JA) from the distal side to its origin. During the procedure, the left sides of the SMA and Treitz ligament are exposed. The Treitz ligament is retracted to the left side and dissected anteriorly. Thereafter, the jejunum is flipped to the right side and the retroperitoneum around the origin of the jejunum and duodenum is dissected to identify the inferior vena cava (IVC). The rest of the Treitz ligament is dissected posteriorly and complete resection of the Treitz ligament releases the limitation of duodenal immobility. Thereafter, dissection proceeds along the anterior wall of the IVC, and mobilization of the pancreas head is completed from the left side., Results: A total of 75 consecutive patients underwent MIPD from April 2016 to July 2022. The median operation times of laparoscopic and robotic procedures were 528 min (356-757 min) and 739 min (492-998 min), respectively. The volume of blood loss during laparoscopic and robotic procedures was 415 g (60-4360 g) and 211 g (17-1950 g), respectively. There was no mortality in any of the cases., Conclusion: Mobilization of the pancreas head and left-sided approach using a caudal view will be a safe and useful technique for MIPD., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Although chemotherapy has been an essential treatment for cancer, the development of immune checkpoint blockade therapy was revolutionary, and a comprehensive understanding of the immunological tumor microenvironment (TME) has become crucial. Here, we investigated the impact of neoadjuvant chemotherapy (NAC) on immune cells in the TME of human esophageal squamous cell carcinoma using single cell RNA-sequencing. Analysis of 30 fresh samples revealed that CD8+/CD4+ T cells, dendritic cells (DCs), and macrophages in the TME of human esophageal squamous cell carcinoma showed higher levels of an anti-tumor immune response in the NAC(+) group than in the NAC(-) group. Furthermore, the immune cells of the NAC(+) group interacted with each other resulting in enhanced anti-tumor immune response via various cytokines, including IFNG in CD8+/CD4+ T cells, EBI3 in DCs, and NAMPT in macrophages. Our results suggest that NAC potentially enhances the anti-tumor immune response of immune cells in the TME., Competing Interests: The authors declare no competing interests., (© 2023 The Authors.)

Purpose: A diagnostic and treatment strategy for appendiceal tumors (ATs) has not been established. We aimed to evaluate our treatment strategy in ATs, including laparoscopic surgery (LS), and to identify preoperative malignancy predictors., Methods: A total of 51 patients between 2011 and 2021 were retrospectively reviewed. Data, including tumor markers and imaging findings, were compared between carcinoma and non-carcinoma patients. Validity of planned operation was evaluated based on pathological diagnosis., Results: Twenty-five patients were diagnosed with carcinoma, 13 with low-grade mucinous neoplasm, and 13 with other diseases. Symptoms were more commonly present in carcinoma patients than in non-carcinoma patients (68.0% vs. 23.1%, p = 0.001). Elevated CEA and CA19-9 were more frequently observed in carcinoma patients than in non-carcinoma patients (p < 0.01 and p = 0.04, respectively). Five carcinoma patients had malignancy on biopsy, compared with zero non-carcinoma patients. Significant differences were noted in the percentages of carcinoma and non-carcinoma patients with solid enhanced mass (41.7% vs. 0%, p < 0.001) and tumor wall irregularity (16.7% vs. 0%, p = 0.03) on imaging. Although the sensitivity was not high, the specificity and positive predictive value of these findings were 100%. Forty-two patients (82.4%) underwent LS as minimally invasive exploratory and/or radical operation, of whom 2 were converted to open surgery for invasion of adjacent organ. No patients had intraoperative complications or postoperative mortality., Conclusion: Clinical symptoms, elevated tumor markers, and worrisome features of solid enhanced mass and tumor wall irregularity on imaging can be malignancy predictors. For management of ATs, LS is feasible and useful for diagnosis and treatment., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: To determine whether N3 nodal involvement predicts outcomes and whether its prognostic implications vary with tumor location in patients with Stage III colon cancer (CC)., Methods: We defined N3 as lymph node metastases near the bases of the major feeding arteries. We retrospectively examined recurrence rates and patterns by tumor location and sites of lymph node metastases in 57 patients with N3 CC who had undergone curative resections between January 2000 and March 2019. Survival analysis was performed to compare the prognoses of patients with and without N3 lymph node metastasis., Results: Most N3 patients had large tumors (T ≥ 3); five had T2 disease. Recurrence occurred quickly in one patient with T2N3M0 disease. Multivariate survival analysis demonstrated that N3 lymph node metastasis is an independent predictor of poor prognosis in Stage III CC patients (P < 0.001). Categorizing N3 patients according to UICC-TNM staging system does not stratify risk of recurrence (P = 0.970). To investigate the impact of tumor location on recurrence risk, we classified N3 CC into two subtypes according to tumor location: metastasis at the base of the superior mesenteric artery in right-sided CC and inferior mesenteric artery in left-sided CC. The former was found to have a statistically significant poorer prognosis than the latter (P = 0.091)., Conclusion: N3 is a robust prognostic marker in CC patients. Recurrence risk varies by tumor location. N3 right-sided CCs with lymph node metastasis at the base of the superior mesenteric artery have poorer prognoses than do N3 left-sided CCs., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Mucosal incision-assisted biopsy (MIAB) is a valuable alternative to endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNAB) for sampling gastric subepithelial lesions (SELs). This study aimed to evaluate the potential risk of dissemination and impact on postoperative prognosis associated with MIAB, which has not yet been investigated., Methods: Study 1: A prospective observational study was conducted to examine the presence or absence and growth rate of tumor cells in gastric juice before and after the procedure in patients with SELs who underwent MIAB (n = 25) or EUS-FNAB (n = 22) between September 2018 and August 2021. Study 2: A retrospective study was conducted to examine the impact of MIAB on postoperative prognosis in 107 patients with gastrointestinal stromal tumors diagnosed using MIAB (n = 39) or EUS-FNAB (n = 68) who underwent surgery between January 2001 and July 2020., Results: In study 1, although no tumor cells were observed in gastric juice in MIAB before the procedure, they were observed in 64% of patients after obtaining samples (P < 0.001). In contrast, no tumor cells were observed in the gastric juice in EUS-FNAB before and after the procedure. In study 2, there was no significant difference in 5-year disease-free survival between MIAB (100%) and EUS-FNAB (97.1%) (P = 0.27)., Conclusion: MIAB is safe, with little impact on postoperative prognosis, although the procedure releases some tumor cells after damaging the SEL's pseudocapsule., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Tumour immune microenvironment is related with carcinogenesis and efficacy of immunotherapy. B cells play major roles in humoral immunity, but detailed functions of tumour-infiltrating B lymphocytes (TIL-Bs) are unknown. Therefore, our aim was to investigate the functional heterogeneity of TIL-Bs in oesophageal squamous cell carcinoma (ESCC) and lymph nodes (LNs) during chemotherapy., Methods: Single-cell transcriptome analysis was performed on 23 specimens. We also performed immunohistochemical analysis of immunoglobulin κ C (IGKC), an antibody-secreting cell (ASC) marker, in 166 ESCC samples and evaluated the implication of IGKC in 2-year recurrence free survival (RFS) and 3-year overall survival (OS)., Results: A total of 81,246 cells were grouped into 24 clusters. We extracted B cell clusters based on canonical markers and identified 12 TIL-B subtypes in ESCC. We found that several functions, such as co-stimulation and CD40 signalling, were enhanced in TIL-Bs after chemotherapy. The proportion of naive B cells (NBCs) decreased and B cell activation genes were up-regulated in NBCs after chemotherapy. The proportion of ASCs in tumours increased with the loss of migratory abilities and antibody production in ASCs was promoted after chemotherapy. Differentially expressed genes up-regulated with chemotherapy in ASCs correlated with prolonged survival with oesophageal cancer (p = .028). In a metastatic LN, the ASC proportion increased and B cell differentiation was enhanced. In immunohistochemical analysis, RFS and OS of high IGKC expression cases were significantly better than those of low IGKC expression cases (RFS: p < .0001, OS: p < .0001). And in multivariable analysis, the expression of IGKC was an independent favourable prognostic factor for RFS (hazard ratio (HR): 0.23, 95% confidence interval (CI): 0.12-0.45, p < .0001) and OS (HR: 0.20, 95% CI: 0.086-0.47, p = .0002) in ESCC., Conclusions: Our findings provide novel insights for the heterogeneity of TIL-Bs during chemotherapy and will be useful to understand the clinical importance of TIL-Bs., (© 2023 The Authors. Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.)

Purpose: Preoperative sarcopenia worsens postoperative outcomes in various cancer types including colorectal cancer. However, we often experienced postoperative anastomotic leakage in muscular male patients such as Judo players, especially in rectal cancer surgery with lower anastomosis. It is controversial whether the whole skeletal muscle mass impacts the potential for anastomotic failure in male rectal cancer patients. Thus, the purpose of this study was to clarify whether skeletal muscle mass impacts anastomotic leakage in rectal cancer in men., Methods: We reviewed the medical charts of male patients suffering from rectal cancer who underwent colo-procto anastomosis below the peritoneal reflection without a protective diverting stoma. We measured the psoas muscle area and calculated the psoas muscle index., Results: One hundred ninety-seven male rectal cancer patients were enrolled in this study. The psoas muscle index was significantly higher in patients with anastomotic leakage (P<0.001). Receiver operating characteristic curve determined the optimal cut-off value of the psoas muscle index for predicting anastomotic leakage as 812.67 cm2/m2 (sensitivity of 60% and specificity of 74.3%). Multivariate analysis revealed that high psoas muscle index (risk ratio [RR], 3.933; P<0.001; 95% confidence interval [CI], 1.917-8.070) and super low anastomosis (RR, 2.792; P=0.015; 95% CI, 1.221-6.384) were independent predictive factors of anastomotic leakage., Conclusion: This study showed that male rectal cancer patients with a large psoas muscle mass who underwent lower anastomosis had a higher rate of postoperative anastomotic leakage.

Background: Loss of E-cadherin expression is frequently observed in signet ring carcinoma (SRCC). People with germline mutations in CDH1, which encodes E-cadherin, develop diffuse gastric cancer at a higher rate. Loss of E-cadherin expression is thus assumed to trigger oncogenic development., Methods: To investigate novel therapeutic targets for gastric SRCC, we engineered an E-cadherin-deficient SRCC model in vitro using a human gastric organoid (hGO) with CDH1 knockout (KO)., Results: CDH1 KO hGO cells demonstrated distinctive morphological changes similar to SRCC and high cell motility. RNA-sequencing revealed up-regulation of matrix metalloproteinase (MMP) genes in CDH1 KO hGO cells compared to wild type. MMP inhibitors suppressed cell motility of CDH1 KO hGO cells and SRCC cell lines in vitro. Immunofluorescent analysis with 95 clinical gastric cancer tissues revealed that MMP-3 was specifically abundant in E-cadherin-aberrant SRCC. In addition, CXCR4 molecules translocated onto the cell membrane after CDH1 KO. Addition of CXCL12, a ligand of CXCR4, to the culture medium prolonged cell survival of CDH1 KO hGO cells and was abolished by the inhibitor, AMD3100. In clinical SRCC samples, CXCL12-secreting fibroblasts showed marked infiltration into the cancer area., Conclusions: E-cadherin deficient SRCCs might gain cell motility through upregulation of MMPs. CXCL12-positive cancer-associated fibroblasts could serve to maintain cancer-cell survival as a niche. MMPs and the CXCL12/CXCR4 axis represent promising candidates as novel therapeutic targets for E-cadherin-deficient SRCC., (© 2022. The Author(s) under exclusive licence to The International Gastric Cancer Association and The Japanese Gastric Cancer Association.)

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, with a 5-year survival rate of 9%. Cancer-associated fibroblasts (CAFs) have historically been considered tumor-promoting. However, multiple studies reporting that suppression of CAFs in PDAC mouse models resulted in more aggressive tumors and worse prognosis have suggested the existence of a tumor-suppressive population within CAFs, leading to further research on heterogeneity within CAFs. In recent years, the benefits of cancer immunotherapy have been reported in various carcinomas. Unfortunately, the efficacy of immunotherapies in PDAC has been limited, and the CAF-driven cancer immunosuppressive microenvironment has been suggested as the cause. Thus, clarification of heterogeneity within the tumor microenvironment, including CAFs and tumor immunity, is urgently needed to establish effective therapeutic strategies for PDAC. In this review, we report the latest findings on the heterogeneity of CAFs and the functions of each major CAF subtype, which have been revealed by single-cell RNA sequencing in recent years. We also describe reports of tumor-suppressive CAF subtypes and the existence of CAFs that maintain a differentiated PDAC phenotype and review the potential for targeted therapy.

For stage II and III esophageal squamous cell carcinoma (ESCC), neoadjuvant chemotherapy (NAC) followed by esophagectomy is recommended in the Japanese guidelines for the diagnosis and treatment of esophageal cancer. However, recurrence of ESCC is common regardless of the NAC regimen and surgical method, and NAC demonstrates limited efficacy against recurrence. Therefore, the present study was conducted to identify risk factors of recurrence of ESCC with surgery after NAC. The outcomes of 51 patients who underwent esophagectomy for ESCC after NAC from 2010 to 2017 at Kyushu University Hospital were retrospectively analyzed. A total of 52 patients with ESCC without NAC followed by esophagectomy from 2001 to 2017 were selected for comparison. Among patients who underwent NAC followed by surgery, only lymphatic invasion (LY; hazard ratio, 2.761; 95% CI, 1.86-6.43, P=0.018) was an independent factor significantly associated with 3-year recurrence-free survival in the multivariate analysis. In patients with pathologic lymph node metastasis (pN) and no LY after NAC, there was significantly less recurrence compared with patients with pN and LY (P=0.0085), whereas in patients without LY after NAC, the presence of pN was not significantly associated with recurrence (P=0.2401). There were significantly fewer LY (+) patients in the NAC (+) group (P=0.0158) compared with those in the NAC (-) group. The presence of LY was an independent risk factor for recurrence of ESCC after esophagectomy following NAC. Overall, adjuvant treatment after surgery may be required in cases with remnant LY after NAC., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Okuda et al.)

Background: Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma in which microenvironmental (niche) factors promote PDAC progression. In mouse models, reduction of the stroma increased the proportion of poorly differentiated PDAC with a worse prognosis. Here, we aimed to clarify the effects of stroma on PDAC that may define the PDAC phenotype and induce distinct therapeutic responses., Methods: The molecular features of PDAC based on differentiation grade were clarified by genome and transcriptome analysis using PDAC organoids (PDOs). We identified the dependency on niche factors that might regulate the differentiation grade. A three-dimensional co-culture model with cancer-associated fibroblasts (CAFs) was generated to determine whether CAFs provide niche factors essential for differentiated PDAC. PDOs were subtyped based on niche factor dependency, and the therapeutic responses for each subtype were compared., Results: The expression profiles of PDOs differed depending on the differentiation grade. Consistent with the distinct profiles, well differentiated types showed high niche dependency, while poorly differentiated types showed low niche dependency. The three-dimensional co-culture model revealed that well differentiated PDOs were strongly dependent on CAFs for growth, and moderately differentiated PDOs showed plasticity to change morphology depending on CAFs. Differentiated PDOs upregulated the expression of mevalonate pathway-related genes correlated with the niche dependency and were more sensitive to simvastatin than poorly differentiated PDOs., Conclusions: Our findings suggest that CAFs maintain the differentiated PDAC phenotype through secreting niche factors and induce distinct drug responses. These results may lead to the development of novel subtype-based therapeutic strategies., (© 2022. The Author(s).)

Background/objectives: Pancreatic ductal adenocarcinoma (PDAC) is characterized by excessive desmoplasia and autophagy-dependent tumorigenic growth. Pancreatic stellate cells (PSCs) as a predominant stromal cell type play a critical role in PDAC biology. We have previously reported that autophagy facilitates PSC activation, however, the mechanism remains unknown. We investigated the mechanism of autophagy in PSC activation., Methods: We compared gene expression profiles between patient-derived PSCs from pancreatic cancer and chronic pancreatitis using a microarray. The stromal expression of target gene in specimen of PDAC patients (n = 63) was analyzed. The effect of target gene on autophagy and activation of PSCs was investigated by small interfering RNAs transfection, and the relationship between autophagy and ER stress was investigated. We analyzed the growth and fibrosis of xenografted tumor by orthotopic models., Results: In analysis of gene expression microarray, endoplasmic reticulum aminopeptidase 2 (ERAP2) upregulated in cancer-associated PSCs was identified as the target gene. High stromal ERAP2 expression is associated with a poor prognosis of PDAC patients. Knockdown of ERAP2 inhibited unfolded protein response mediated autophagy, and led to inactivation of PSCs, thereby attenuating tumor-stromal interactions by inhibiting production of IL-6 and fibronectin. In vivo, the promoting effect of PSCs on xenografted tumor growth and fibrosis was inhibited by ERAP2 knockdown., Conclusions: Our findings demonstrate a novel mechanism of PSCs activation regulated by autophagy. ERAP2 as a promising therapeutic target may provide a novel strategy for the treatment of PDAC., Competing Interests: Declaration of competing interest The authors have no conflict of interest., (Copyright © 2021 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Purpose: T1 gastric cancer (GC) with seven or more metastatic lymph nodes is extremely rare, and very few clinical studies have been conducted to evaluate the clinicopathological features of their recurrence., Methods: We retrospectively analyzed the outcomes of T1 GC and T2-4 GC patients who had multiple nodal metastases after radical surgery from 2006 to 2020. Propensity score matching was performed to compare the two groups of patients., Results: After propensity score matching, 18 of 22 patients in the T1 group and 36 of 144 patients in the T2-4 group were selected. Recurrence occurred in six patients (33.3%) in the T1 group. In the T1 group, the most common site of initial recurrence was bone (15.0%). The prevalence of bone recurrence was significantly higher in the T1 group than in the T2-4 group (P = 0.02). The median interval time between radical surgery and bone recurrence was 24 months, and the median survival time after bone recurrence was 14 months., Conclusion: Bone recurrence was more frequently identified as an initial recurrence site in T1 GC cases with multiple metastases after radical surgery compared with that in T2-4 GC cases. Careful attention should be paid to postoperative bone recurrence in the long-term postoperative course of these patients., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Pancreatic cancer cells (PCCs) are surrounded by an abundant stroma, which is produced by pancreatic stellate cells (PSCs). PSCs promote tumor cell proliferation and invasion. The objective of the current study was to identify compounds that suppress PSC activation. Gene expression profiles of cancer-derived fibroblasts and normal fibroblasts were used, and the pathway analysis suggested altered pathways that were chosen for validation. It was found that the 'neuroactive ligand-receptor interaction' pathway from the Kyoto Encyclopedia of Genes and Genomes pathway analysis was one of the altered pathways. Several compounds related with this pathway were chosen, and changes in PSC activity were investigated using fluorescence staining of lipid droplets, reverse transcription-quantitative PCR, western blotting, and invasion and migration assays. Among these candidates, duloxetine, a serotonin-noradrenaline reuptake inhibitor, was found to suppress PSC activation and disrupt tumor-stromal interaction. Thus, duloxetine may be a potential drug for suppressing PSC activation and pancreatic cancer growth., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Sagara et al.)

Pancreatic ductal adenocarcinoma (PDAC) is characterized by notorious resistance to current therapies attributed to inherent tumor heterogeneity and highly desmoplastic and immunosuppressive tumor microenvironment (TME). Unique proline isomerase Pin1 regulates multiple cancer pathways, but its role in the TME and cancer immunotherapy is unknown. Here, we find that Pin1 is overexpressed both in cancer cells and cancer-associated fibroblasts (CAFs) and correlates with poor survival in PDAC patients. Targeting Pin1 using clinically available drugs induces complete elimination or sustained remissions of aggressive PDAC by synergizing with anti-PD-1 and gemcitabine in diverse model systems. Mechanistically, Pin1 drives the desmoplastic and immunosuppressive TME by acting on CAFs and induces lysosomal degradation of the PD-1 ligand PD-L1 and the gemcitabine transporter ENT1 in cancer cells, besides activating multiple cancer pathways. Thus, Pin1 inhibition simultaneously blocks multiple cancer pathways, disrupts the desmoplastic and immunosuppressive TME, and upregulates PD-L1 and ENT1, rendering PDAC eradicable by immunochemotherapy., Competing Interests: Declaration of interests K.K., G.M.W., T.D.M., B.J.P., N.L., N.S.G., X.Z.Z., and/or K.P.L. are inventors of a number of issued patents and/or pending patent applications on Pin1, Pin1 biomarkers, Pin1 inhibitors, and Pin1 inhibitor combination to treat human diseases; X.Z.Z. and K.P.L. are inventors of cis P-tau antibody technology, which was licensed by BIDMC to the startup Pinteon Therapeutics. X.Z.Z. and K.P.L. are the scientific founders and former scientific advisors of and own equity in Pinteon. Their interests were reviewed and are managed by BIDMC in accordance with its conflict of interest policy. G.M.W. reports research funding from Glaxo Smith Kline (institutional funding). N.S.G. is a founder, science advisory board member (SAB), and equity holder in Gatekeeper, Syros, C4, Allorion, Jengu, Inception, B2S, EoCys, Larkspur, and Soltego (board member). The Gray lab receives or has received research funding from Novartis, Takeda, Astellas, Taiho, Jansen, Kinogen, Arbella, Deerfield, and Sanofi. All other authors do not have any competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Pancreatic stellate cells (PSCs) play a key role in desmoplastic stroma, which is a characteristic of pancreatic ductal adenocarcinoma (PDAC), and they also enhance the malignancy of pancreatic cancer cells. Our previous study reported chloroquine's mitigating effects on PSC activation; however, the drug is known to induce adverse effects in clinical practice. The present study aimed to reduce chloroquine doses and develop a useful pre-treatment that targets PSCs using nanoparticles. Poly lactic-co-glycolic acid (PLGA) nanoparticles were used as carriers and loaded with indocyanine green (Nano-ICG) or chloroquine (Nano-CQ). Tumor accumulation of Nano-ICG was evaluated using an in vivo imaging system. The effects of chloroquine, Nano-CQ and/or chemotherapy drug gemcitabine were investigated in an orthotopic xenograft mouse model. Nano-ICG selectively accumulated in pancreatic tumors and persisted therein for over 7 days after administration. Additionally, Nano-ICG accumulated in the peritoneal metastasized regions, but not in the liver, kidney and normal pancreatic tissues. Nano-CQ reduced the density of activated PSCs at lower chloroquine doses and significantly restrained tumor progression in combination with gemcitabine. In conclusion, the PLGA nanosystem successfully delivered the drug to pancreatic tumors. Nano-CQ efficiently reduced PSC activation and may be a promising novel pre-treatment strategy for PDAC., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Matsumoto et al.)

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a desmoplastic reaction caused by cancer-associated fibroblasts (CAFs), which provokes treatment resistance. CAFs are newly proposed to be heterogeneous populations with different functions within the PDAC microenvironment. The most direct sources of CAFs are resident tissue fibroblasts and mesenchymal stem cells, however, the origins and functions of CAF subtypes remain unclear. Here, we established allogeneic bone marrow (BM) transplantation models using spontaneous PDAC mice, and then investigated what subtype cells derived from BM modulate the tumor microenvironment and affect the behavior of pancreatic cancer cells (PCCs). BM-derived multilineage hematopoietic cells were engrafted in recipient pancreas, and accumulated at the invasive front and central lesion of PDAC. We identified BM macrophages-derived CAFs in tumors. BM-derived macrophages treated with PCC-conditioned media expressed CAF markers. BM-derived macrophages led the local invasion of PCCs in vitro and enhanced the tumor invasive growth in vivo. Our data suggest that BM-derived cells are recruited to the pancreas during carcinogenesis and that the specific subpopulation of BM-derived macrophages partially converted into CAF-like cells, acted as leading cells, and facilitated pancreatic cancer progression. The control of the conversion of BM-derived macrophages into CAF-like cells may be a novel therapeutic strategy to suppress tumor growth., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Introduction: The proportion of patients aged 75 years and over who undergo minimally invasive surgery for gastric cancer is increasing. However, the safety and feasibility of laparoscopic gastrectomy (LG) in this age group is controversial. This study aimed to evaluate whether LG is safe and effective in patients aged 75 years and over., Methods: The study included 728 patients with early and advanced gastric cancer who underwent curative LG between 2009 and 2017; 166 of these patients (22.8%) were aged 75 or over. All surgeries were performed laparoscopically. Selected clinical factors were compared between the 166 patients aged 75 years and over and the 562 patients aged under 75 years., Results: There were significant differences in presence of comorbidity, respiratory function and American Society of Anesthesiologists physical status scores between the older and younger groups. The older patients more frequently developed complications than the younger ones, particularly postoperative pneumonia. According to multivariate analyses of all participants, age, chronic obstructive pulmonary disease (COPD), and D2 lymphadenectomy were independent risk factors for postoperative pneumonia. Advanced stage and D2 lymphadenectomy were independent risk factors in the older group, whereas only COPD was an independent risk factor in the younger group., Conclusions: LG for gastric cancer can be safely performed in patients aged over 75 years with an acceptable complication rate. However, the present data suggest that care should be taken in selecting LG with D2 lymphadenectomy to treat advanced cancer in these patients because the risk of postoperative complications, especially postoperative pneumonia, increases., (© 2020 Asia Endosurgery Task Force and Japan Society of Endoscopic Surgery and John Wiley & Sons Australia, Ltd.)

Postoperative adjuvant chemotherapy for patients with stage III colon cancer (CC) is regarded as the standard treatment worldwide for outcome improvement and relapse prevention. Similarly, high-risk stage II CC requires adjuvant chemotherapy because of its high recurrence rate. Previous randomized controlled trials showed that oxaliplatin (OX), in addition to fluorinated pyrimidine-based therapy for patients with stage II/III CC, significantly improves cancer survival but it remains controversial as to which patient groups should receive OX-containing regimens. Among 1,150 consecutive patients who underwent curative resection for stage II/III CC between 2009 and 2016 at two tertiary hospitals, 349 patients treated with only peroral (PO) fluorinated pyrimidine-based chemotherapy and 149 patients who received fluorinated pyrimidine-based chemotherapy with OX as adjuvant chemotherapy were retrospectively reviewed. The primary outcome was recurrence-free survival (RFS). Clinicopathological factors were more advanced in patients treated with OX than in patients treated only with PO fluorinated pyrimidine agents. Multivariate analysis for 5-year RFS showed that T4 [hazard ratio (HR), 2.947; P=0.0001], N2 (HR, 2.704; P=0.0075), vessel or lymphatic invasion (HR, 1.675; P=0.0437) and high cancer antigen (CA)19-9 (HR 3.367, P=0.0002) levels were independent risk factors of cancer relapse. Propensity score matching analysis was performed to match clinicopathological differences between the PO and OX groups. After matching, subgroup analysis of the patients showed that greater effects of OX on cancer survival were observed in patients in the OX group with high CA19-9 levels and tended to be associated with T4 and N2 compared with the PO group. Thus, OX-containing regimens should be recommended for patients with CC with these factors in an adjuvant setting., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2020, Spandidos Publications.)

Background/objectives: Pancreatic stellate cells (PSCs) are involved in abundant desmoplasia, which promotes cancer cell aggressiveness and resistance to anti-cancer drugs. Therefore, PSCs are suggested to be a promising therapeutic target by attenuating PSC activation to inhibit tumor-stromal interactions with pancreatic cancer cells. Here, we developed a screen to identify compounds that reduce the activity of PSCs and investigated the effect of candidates on pancreatic cancer., Methods: Lipid droplet accumulation in PSCs was used to observe differences in PSC activity and a new high-throughput screening platform that quantified lipid droplets in PSCs was established. A library of 3398 Food and Drug Administration-approved drugs was screened by this platform. Validation assays were performed in vitro and in vivo., Results: Thirty-two compounds were finally selected as candidate compounds by screening. These compounds decreased α-smooth muscle actin expression and inhibited autophagic flux in PSCs in vitro. Among the candidates, three drugs selected for validation assays inhibited the proliferation and migration of PSCs and invasion of cancer cells by disrupting tumor-stromal interactions. Production of extracellular matrix molecules was also decreased significantly by this treatment. In vivo testing in xenograft models showed that dopamine antagonist zuclopenthixol suppressed tumor growth; this suppression was significantly increased when combined with gemcitabine., Conclusions: A new screening platform that focused on the morphological features of PSCs was developed. Candidate drugs from this screening suppressed PSC activation and tumor growth. This screening system may be useful to discover new compounds that attenuate PSC activation., Competing Interests: Declaration of competing interest The authors declare no potential conflicts of interest., (Copyright © 2021. Published by Elsevier B.V.)

Background: Pancreatic stellate cells (PSCs) occupy the majority of the pancreatic cancer microenvironment, contributing to aggressive behavior of pancreatic cancer cells (PCCs). Recently, anti-fibrotic agents have proven to be an effective strategy against cancer, but clinical trials have shown little efficacy, and the driving mechanism remains unknown. N-acetyl-cysteine (NAC) is often used for pulmonary cystic fibrosis. Pioglitazone, an agonist of peroxisome proliferator-activated receptor gamma, was habitually used for type II diabetes, but recently reported to inhibit metastasis of PCCs. However, few studies have focused on the effects of these two agents on cancer-stromal interactions., Method: We evaluated the expression of α-smooth muscle actin (α-SMA) and the number of lipid droplets in PSCs cultured with or without NAC. We also evaluated changes in invasiveness, viability, and oxidative level in PSCs and PCCs after NAC treatment. Using an indirect co-culture system, we investigated changes in viability, invasiveness, and migration of PSCs and PCCs. Combined treatment effects of NAC and Pioglitazone were evaluated in PSCs and PCCs. In vivo, we co-transplanted KPC-derived organoids and PSCs to evaluate the effects of NAC and Pioglitazone's combination therapy on subcutaneous tumor formation and splenic xenografted mouse models., Results: In vitro, NAC inhibited the viability, invasiveness, and migration of PSCs at a low concentration, but not those of PCCs. NAC treatment significantly reduced oxidative stress level and expression of α-SMA, collagen type I in PSCs, which apparently present a quiescent-like state with a high number of lipid droplets. Co-cultured PSCs and PCCs mutually promoted the viability, invasiveness, and migration of each other. However, these promotion effects were attenuated by NAC treatment. Pioglitazone maintained the NAC-induced quiescent-like state of PSCs, which were reactivated by PCC-supernatant, and enhanced chemosensitivity of PCCs. In vivo, NAC and Pioglitazone's combination suppressed tumor growth and liver metastasis with fewer stromal components and oxidative stress level., Conclusion: NAC suppressed activated PSCs and attenuated cancer-stromal interactions. NAC induces quiescent-like PSCs that were maintained in this state by pioglitazone treatment.

Purpose: The aim of this study was to investigate the genetic mutation profiles of Japanese pancreatic ductal adenocarcinoma (PDAC) patients., Methods: Next-generation sequencing was performed using FoundationOne® CDx on 17 PDAC patients who were treated by surgical resection at Kyushu University Hospital between February 2016 and January 2019. The tumor mutational burden and microsatellite instability status were also assessed., Results: There were 16 patients (94%) with KRAS mutations, 13 (76%) with TP53 mutations, three (18%) with SMAD4 mutations, and one (6%) with a CDKN2A mutation. All patients had at least one pathogenic variant or a likely pathogenic variant. No patient had targeted therapies that matched with any clinical benefit according to FoundationOne® CDx. An unresectable PDAC patient with BRCA2-mutant disease was successfully treated by conversion surgery using platinum-based neoadjuvant chemotherapy., Conclusions: Currently, FoundationOne® CDx might be difficult to use on PDAC patients, although further investigations with larger study populations are called for.

Introduction: Pancreatic adenocarcinoma (PAAD) is an aggressive malignancy, with a major mortality resulting from the rapid progression of metastasis. Unfortunately, no effective treatment strategy has been developed for PAAD metastasis to date. Thus, unraveling the mechanisms involved in PAAD metastatic phenotype may facilitate the treatment for PAAD patients., Objectives: PIK3CB is an oncogene implicated in cancer development and progression but less is known about whether PIK3CB participates in PAAD metastasis. Therefore, the objective of this study is to explore the mechanism(s) of PIK3CB in PAAD metastasis., Methods: In our study, we examined the PIK3CB expression pattern using bioinformatic analysis and clinical material derived from patients with PAAD. Subsequently, a series of biochemical experiments were conducted to investigate the role of PIK3CB as potential mechanism(s) underlying PAAD metastasis in vivo using nude mice and in vitro using cell lines., Results: We observed that PIK3CB was involved in PAAD progression. Notably, we identified that PIK3CB was involved in PAAD metastasis. Downregulation of PIK3CB significantly reduced PAAD metastatic potential in vivo. Furthermore, a series of bioinformatic analyses showed that PIK3CB was involved in cell adhesion in PAAD. Notably, PIK3CB depletion inhibited invasion potential specifically via suppressing cell adhesion to collagen I in PAAD cells., Conclusion: Collectively, our findings indicate that PIK3CB is involved in PAAD metastasis through cell-matrix adhesion. We proposed that PIK3CB is a potential therapeutic target for PAAD therapy., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors. Published by Elsevier B.V. on behalf of Cairo University. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

Robotic surgery is expanding in the minimally invasive treatment of gastrointestinal cancer. In the field of gastrointestinal cancer, robotic surgery is performed using a robot-assisted surgery system. In this system, the robot does not operate automatically but is controlled by the surgeon. The surgery assistant robot currently used in clinical practice worldwide is the leader-follower type, including the da Vinci® Surgical System (Intuitive Surgical). This review describes the current state of robotic surgery in the treatment of gastrointestinal cancer and discusses the future development of robotic systems in gastrointestinal surgery., Competing Interests: Kenoki Ohuchida has no conflict of interest or financial ties to disclose., (Copyright © 2020 Kenoki Ohuchida.)

Background: Metastatic cancer to the stomach is relatively rare. Prostate-specific antigen (PSA) is a reliable biomarker used in the screening and management of patients with prostate cancer. However, it is difficult to definitively diagnose a PSA-negative metastatic gastric tumor of prostate cancer because the cancer sometimes resembles primary gastric cancer in clinical images. It is also difficult to distinguish metastatic cancer from primary cancer even in the pathological examination of biopsy samples when the lesion is poorly differentiated adenocarcinoma. There is a possibility that the characteristics of the cancer are changed during treatment such as chemotherapy or radiation therapy. Therefore, careful consideration is required for surgical indication., Case Presentation: A 60-year-old male underwent radical prostatectomy and subsequent radiation therapy for advanced prostate cancer (pT3N1M0) 10 years previously, and hormone therapy was started for metachronous multiple bone metastasis 10 months before. Upper gastrointestinal endoscopy revealed an irregular depressed lesion with a convergence of folds at the greater curvature of the upper gastric body. Biopsy showed poorly differentiated adenocarcinoma that was negative for PSA upon immunohistochemistry. He had high serum carcinoembryonic antigen (CEA) (946.1 ng/ml) and carbohydrate antigen 19-9 (CA19-9) (465.1 U/ml) levels with no elevation of PSA (0.152 ng/ml). The tumor was diagnosed as primary gastric cancer based on the clinical imaging and pathological examination of the biopsy sample including the PSA staining. Based on the diagnosis, laparoscopic proximal gastrectomy with lymphadenectomy was performed. However, pathological examination of the resected specimen revealed poorly differentiated adenocarcinoma that was positive for other prostate markers such as androgen receptor. Thus, the patient was diagnosed with metastasized prostate cancer to the stomach., Conclusions: We report a case of metastatic gastric cancer of prostate cancer 10 years after radical prostatectomy. In the present case, it was difficult to diagnose a metastatic gastric tumor of prostate cancer preoperatively, because of its resemblance to primary gastric cancer without PSA expression and no serum PSA elevation. Although a rare case entity, it is important to consider the possibility of a metastatic gastric tumor when the surgical indication is determined in cases with another co-existing cancer.

Purpose: To identify the incidence of extraction site incisional hernia following gastrectomy for gastric cancer and its significant risk factors, including the subcutaneous fat area., Methods: We reviewed data gathered prospectively on patients with gastric cancer, who underwent gastrectomy between 2008 and 2012 at Kyushu University Hospital, Fukuoka, Japan. The subcutaneous fat area (SFA) and visceral fat area (VFA) were measured using axial computed tomography at the level of the L4 and L3 transverse processes, and the L2-L3 intervertebral disc. The primary endpoint of the rate of extraction site incisional hernia was based on the computed tomography and clinical data including hospital follow-up reports., Results: After applying the inclusion and exclusion criteria, 320 patients were included in this retrospective analysis: 3.1% (10/320) had extraction site incisional hernias after a mean follow-up of 11 months. Multivariate analysis revealed that age and the SFA were independent risk factors (age ≥ 70.5 years: P = .013, odds ratio: 9.116, 95% confidence interval 1.581-52.553; L4 SFA ≥ 124 cm 2 : P = .004, odds ratio: 13.752, 95% confidence interval 2.290-82.582)., Conclusion: Age and the SFA were independent risk factors for extraction site incisional hernia in patients undergoing gastrectomy for gastric cancer.

Recently, several scholars have demonstrated the efficacy of carbon ion radiotherapy (CIRT). To treat abdominal or pelvic tumors by CIRT, it is necessary to separate the tumor from the adjacent organs. Surgical placement of a GORE-TEX sheet as a spacer has been reported as a separation method. Usually, surgical spacer placement is done by open surgery. Here, we report a case of surgical spacer placement undertaken by a "pure" laparoscopic procedure. A 47-year-old man with recurrent sacral chordoma was referred for surgical spacer placement before CIRT. Laparoscopic dissection of the rectum and placement of a GORE-TEX sheet as a spacer were successfully performed. Surgical spacer placement by a pure laparoscopic procedure was safe and effective, and it seems to play an important part before CIRT., (© 2020 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.)

Purpose: There is no definite evidence of the feasibility and safety of laparoscopic distal gastrectomy (LDG) for patients who have undergone incomplete endoscopic resection (ER). We investigated the influence of ER prior to LDG by a propensity score matching analysis., Methods: We retrospectively analyzed the outcomes of gastric cancer patients who underwent LDG with or without prior ER from 2000 to 2014. Propensity score matching was performed to compare the two groups of patients., Results: After matching, 47 patients in the ER group and 94 patients in the non-ER group were selected from a total of 365 patients. A residual tumor was observed in 10 of 47 patients (21.3%). The mean number of dissected lymph nodes in the non-ER group (39.4 ± 14.5) was higher than that in the ER group (31.7 ± 13.5) (P = 0.003). However, other perioperative data, such as the operation time and blood loss volume were similar. The complication rate of the ER group (17.0%) and the non-ER group (9.6%) did not differ to a statistically significant extent (P = 0.2). Among these patients, 6 died during the 5-year follow-up period, but no patients showed signs of recurrence., Conclusion: ER prior to surgical resection showed no significant influence on postoperative complications or mortality. LDG can be safely performed to achieve radical resection after incomplete ER.

Rationale: Pancreatic cancer is one of the most difficult cancers to manage and its poor prognosis stems from the lack of a reliable early disease biomarker coupled with its highly metastatic potential. Liver metastasis accounts for the high mortality rate in pancreatic cancer. Therefore, a better understanding of the mechanism(s) underlying the acquisition of the metastatic potential in pancreatic cancer is highly desirable. Methods: Microarray analysis in wild-type and highly liver metastatic human pancreatic cancer cell lines was performed to identify gene expression signatures that underlie the metastatic process. We validated our findings in patient samples, nude mice, cell lines and database analysis. Results: We identified a metastasis-related gene, laminin subunit alpha 4 ( LAMA4 ), that was upregulated in highly liver metastatic human pancreatic cancer cell lines. Downregulation of LAMA4 reduced the liver metastatic ability of pancreatic cancer cells in vivo . Furthermore, LAMA4 expression was positively correlated with tumor severity and in silico analyses revealed that LAMA4 was associated with altered tumor microenvironment. In particular, our in vitro and i n vivo results showed that LAMA4 expression was highly correlated with cancer-associated fibroblasts (CAFs) level which may contribute to pancreatic cancer metastasis. We further found that LAMA4 had a positive effect on the recruitment and activity of CAFs. Conclusions: These data provide evidence for LAMA4 as a possible biomarker of disease progression and poor prognosis in pancreatic cancer. Our findings indicate that LAMA4 may contribute to pancreatic cancer metastasis via recruitment or activation of CAFs., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Progress in diagnostic modalities, surgical procedures, and multidisciplinary treatment for pancreatic diseases has increased the number of long-term survivors after pancreatic resection. Several reports have focused on high-risk lesions (HRLs), including high-grade pancreatic intraepithelial neoplasia (PanIN), pancreatic ductal adenocarcinoma, high-grade intraductal papillary mucinous neoplasm (IPMN), and IPMN with an associated invasive carcinoma, in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The etiology of HRLs in the remnant pancreas is thought to be either isolated local recurrence of the initial lesion in the remnant pancreas or a newly developed primary lesion. Although it is difficult to distinguish between local recurrence and a new primary lesion, comparison of genetic alterations between two lesions may help with this distinction. Early detection of HRLs in the remnant pancreas may improve the prognosis of patients, and several investigators have proposed predictive factors for HRLs in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The reported short- and long-term outcomes of surgical resection of HRLs in the remnant pancreas are relatively favorable. Life-long surveillance of the remnant pancreas is recommended after partial pancreatic resection for pancreatic cancer or IPMN.

Background: The standard surgical method for symptomatic submucosal tumors (SMTs) or tumors with unclear biological behavior is enucleation. Minimally invasive approaches are usually considered appropriate for surgical enucleation; thus, thoracoscopic and laparoscopic enucleation is performed widely and safely. However, it is sometimes difficult to enucleate large and complicated esophageal tumors using thoracoscopic surgery, and even if rare, there is the risk of requiring thoracotomy or esophagectomy. In the present case, we enucleated a large and complicated leiomyoma safely using a new combined method with endoscopic and thoracoscopic procedures., Case Presentation: A 42-year-old woman presented to our hospital for a detailed examination of an abnormal finding in her health check-up chest X-ray images. She complained of upper abdominal pain after eating, and computed tomography revealed an esophageal tumor measuring 60 mm in length surrounding her lower thoracic esophagus. Esophagogastroduodenoscopy revealed a huge complicated SMT at the esophagogastric junction. Cytological examination with endoscopic ultrasound-guided fine-needle aspiration showed that the tumor was a leiomyoma. To enucleate this large and complicated esophageal SMT safely and without damaging the esophageal mucosa, we performed endoscopic and thoracoscopic procedures. We created a submucosal tunnel, endoscopically, and then performed thoracoscopic surgery to enucleate the tumor completely from the esophageal muscularis. Using these combined procedures, we were able to easily mobilize even a complicated tumor of this size from the mucosa and completed the surgery thoracoscopically without difficulty. As a result, the tumor was dissected safely with a minimal defect in the muscularis and without damaging the mucosa. Finally, we closed the defect in the esophageal muscularis with continuous sutures, thoracoscopically, and closed the entry of the submucosal tunnel using clips, endoscopically., Conclusions: Using these combined procedures, we safely enucleated a huge complicated esophageal SMT. The increased mobility of the tumor after creating the submucosal tunnel contributed to the minimal defect in the muscular layer and prevented injury to the esophageal mucosa, possibly leading to fewer postoperative complications such as esophageal stenosis and local infection.

Pancreatic ductal adenocarcinoma (PDAC) is resistant to immunotherapy. As a factor of resistance, the dense fibrosis of this cancer acts as a barrier to inhibit immune cell infiltration into a tumor. We examined the influence of a Hedgehog signal inhibitor, Patched 1-interacting peptide, on fibrosis, infiltration of immune cells, and immunotherapeutic effects on PDAC. We found that this peptide inhibited proliferation and migration of cancer-associated fibroblasts and cancer cells. Furthermore, this peptide reduced the production of extracellular matrix and transforming growth factor β1 in cancer-associated fibroblasts and induced expression of HLA-ABC in PDAC cells and interferon-γ in lymphocytes. In vivo, the peptide suppressed fibrosis of PDAC and increased immune cell infiltration into tumors. The combination of this peptide and an anti-programmed death-1 antibody augmented the antitumor effect, and this combination showed the same effect in experiments using cancer cells and autologous lymphocytes. These results indicate that, in addition to the direct effect of tumor suppression, the Patched 1-interacting peptide increases the infiltration of immune cells by reducing fibrosis of PDAC and consequently enhances the effect of immunotherapy. Therefore, treatment with this peptide may be a novel therapy with 2 different mechanisms: direct tumor suppression and enhancing the immune response against PDAC.

Cancer‑associated fibroblasts (CAFs) promote the progression of pancreatic ductal adenocarcinoma (PDAC) via tumor‑stromal interactions. Neutrophil extracellular traps (NETs) are extracellular DNA meshworks released from neutrophils together with proteolytic enzymes against foreign pathogens. Emerging studies suggest their contribution to liver metastasis in several types of cancer. Herein, in order to investigate the role of NETs in liver metastasis in PDAC, the effects of NET inhibitors on spontaneous PDAC mouse models were evaluated. It was demonstrated that DNase I, a NET inhibitor, suppressed liver metastasis. For further investigation, further attention was paid to liver micrometastasis and an experimental liver metastasis mouse model was used that was generated by intrasplenic tumor injection. Furthermore, DNase I also suppressed liver micrometastasis and notably, CAFs accumulated in metastatic foci were significantly decreased in number. In vitro experiments revealed that pancreatic cancer cells induced NET formation and consequently NETs enhanced the migration of hepatic stellate cells, which was the possible origin of CAFs in liver metastasis. On the whole, these results suggest that NETs promote liver micrometastasis in PDAC via the activation of CAFs.