Genetic assessment of IPMN for predicting concomitant pancreatic ductal adenocarcinoma.

OBJECTIVE: Krüppel-like transcription factor 4(KLF4) mutations are more frequently observed in low-grade lesions than in high-grade lesions of intraductal papillary mucinous neoplasms (IPMN) of the pancreas. However, the role of KLF4 mutations in IPMNs with concomitant pancreatic ductal adenocarcinoma (PDAC) remains unclear. This study clarified the rate and effect of KLF4 mutations in IPMN with concomitant PDAC. METHODS: DNA was extracted from 65 formalin-fixed and paraffin-embedded samples from 52 patients including 13 IPMN with concomitant PDAC and 39 IPMN alone. A comprehensive screening was performed using next-generation sequencing (NGS) for the 5 IPMNs with concomitant PDAC and 5 IPMNs alone, followed by targeted sequencing for KLF4, GNAS, and KRAS mutations. RESULTS: In NGS screening, KRAS mutations were observed in all samples except for one, GNAS mutation in two IPMNs with concomitant PDAC, and a KLF4 mutation in one IPMN with concomitant PDAC. Targeted sequence detected KLF4 mutations in 11 of the 52 IPMNs. Concomitant PDAC developed only in the non-intestinal, non-invasive, and branch duct IPMN cases, and KLF4 mutations were more frequent in this IPMN type than in the other type (36% vs. 10%, p = 0.04). For this IPMN type with KLF4 mutation, PDAC-prediction sensitivity, specificity, and accuracy were 63%, 82%, and 79%, respectively. CONCLUSION: For selected IPMNs with non-intestinal, non-invasive, and branch duct, genetic assessment might be a helpful tool for predicting the possible development of concomitant PDAC, although a prospective validation study using a larger study population is needed.

Factors Affecting Nonfunctioning Small Pancreatic Neuroendocrine Neoplasms and Proposed New Treatment Strategies.

BACKGROUND & AIMS: Despite previously reported treatment strategies for nonfunctioning small (≤20 mm) pancreatic neuroendocrine neoplasms (pNENs), uncertainties persist. We aimed to evaluate the surgically resected cases of nonfunctioning small pNENs (NF-spNENs) in a large Japanese cohort to elucidate an optimal treatment strategy for NF-spNENs. METHODS: In this Japanese multicenter study, data were retrospectively collected from patients who underwent pancreatectomy between January 1996 and December 2019, were pathologically diagnosed with pNEN, and were treated according to the World Health Organization 2019 classification. Overall, 1490 patients met the eligibility criteria, and 1014 were included in the analysis cohort. RESULTS: In the analysis cohort, 606 patients (59.8%) had NF-spNENs, with 82% classified as grade 1 (NET-G1) and 18% as grade 2 (NET-G2) or higher. The incidence of lymph node metastasis (N1) by grade was significantly higher in NET-G2 (G1: 3.1% vs G2: 15.0%). Independent factors contributing to N1 were NET-G2 or higher and tumor diameter ≥15 mm. The predictive ability of tumor size for N1 was high. Independent factors contributing to recurrence included multiple lesions, NET-G2 or higher, tumor diameter ≥15 mm, and N1. However, the independent factor contributing to survival was tumor grade (NET-G2 or higher). The appropriate timing for surgical resection of NET-G1 and NET-G2 or higher was when tumors were >20 and >10 mm, respectively. For neoplasms with unknown preoperative grades, tumor size >15 mm was considered appropriate. CONCLUSIONS: NF-spNENs are heterogeneous with varying levels of malignancy. Therefore, treatment strategies based on tumor size alone can be unreliable; personalized treatment strategies that consider tumor grading are preferable.

Clinical effectiveness of microporous polysaccharide hemospheres in mastectomy for patients with breast cancer.

Background: Microporous polysaccharide hemospheres (MPH) are hydrophilic particles administered to reduce the incidence of seroma after mastectomy, but their clinical effectiveness remains controversial. Because a previous randomized, controlled study in a small cohort could not demonstrate the effectiveness of MPH in breast surgery, we evaluated their effectiveness in surgery for breast cancer in a larger cohort. Methods: Medical records of 352 patients who underwent total mastectomy for breast cancer were retrospectively reviewed. Clinical data were compared between 126 patients who received MPH during surgery (MPH group) and 226 who did not (control group) according to surgical procedures. Patients were significantly older in the MPH group than in the control group because of selection bias, but other factors, such as body mass index and number of dissected lymph nodes, did not differ between groups. Results: When analyzed by use of axillary manipulation, the drain placement period and drainage volume were significantly less in the MPH group than in the control group for patients with mastectomy and sentinel lymph node biopsy. Only drainage volume was significantly less in the MPH group for patients with mastectomy and axillary lymph node dissection. The frequency of total postoperative complications, such as seroma requiring puncture, did not differ between groups. Conclusions: Use of MPH may decrease the postoperative drainage volume and drain placement period in mastectomy for patients with breast cancer.

A sutureless overlapped anastomosis technique using linear staplers with reinforced bioabsorbable material in robotic right colectomy with intracorporeal anastomosis.

AIM: Creation of an overlapped anastomosis using handsewn sutures for common enterotomy is very popular in robotic right colectomy (RRC) with intracorpareal anastomosis (IA). The aim of this study is to present a simple method for constructing a sutureless overlapped anastomosis using a 60 mm linear stapler with a reinforced bioabsorbable material in RRC with IA. METHOD: The distal ileum and proximal colon were put in overlapping positions. Enterotomies were created 2 cm proximal to the ileal stump and 8 cm distal to the colonic stump on the antimesenteric side. Subsequently, a 60 mm linear stapler with a reinforced bioabsorbable material was inserted into each lumen and fired. Finally, the bowel was elevated while holding the bioabsorbable material, and the common enterotomy was grasped with the robotic instrument in the middle and closed using a linear stapler with a reinforced bioabsorbable material. RESULTS: This technique was applied to 10 patients with tumours of the caecum, ascending colon, or transverse colon. The median operating time, anastomosis construction time, blood loss, and postoperative stay were 281 min (range 228-459 min), 12 min (range 11-17 min), 10 mL (range 0-110 mL), and 10 days (range 8-15 days), respectively. No adverse intraoperative events were observed. Postoperatively, one patient developed chylous ascites, but there were no other complications. CONCLUSION: The simple technique for constructing a sutureless overlapped anastomosis using a 60 mm linear stapler with a reinforced bioabsorbable material in robotic right colectomy with intracorporeal anastomosis appears to be safe and feasible.

Successful subtotal gastrectomy and hepatectomy for HER2-positive gastric cancer with liver metastasis after trastuzumab-based chemotherapy: a case report.

BACKGROUND: Conversion surgery (CS) after chemotherapy is weakly recommended as a promising tool for improving prognoses in patients with unresectable gastric cancer. Moreover, several investigators have demonstrated the clinical efficacy of subtotal gastrectomy (sTG) with a small remnant stomach for the nutritional status and surgical outcome compared with total gastrectomy. Here, we report a patient with liver metastasis from human epidermal growth factor receptor 2 (HER2)-positive gastric cancer who underwent sTG and hepatectomy after trastuzumab-based chemotherapy. CASE PRESENTATION: An 84-year-old male patient was diagnosed with HER2-positive gastric cancer with a single liver metastasis. He was treated with eight courses of trastuzumab in combination with S-1 and oxaliplatin as first-line chemotherapy. The primary tumor and liver metastasis shrank significantly. The metastatic liver lesion's reduction rate was 65%. According to the Response Evaluation Criteria in Solid Tumors, the patient had a partial response. Therefore, he underwent an sTG with D2 lymphadenectomy and partial hepatectomy of segment 2. Histopathological examination revealed a grade 3 histological response without lymph node metastases from the primary tumor. No viable cancer cells were observed in the resected liver specimens. The patient received adjuvant chemotherapy with S-1. The postoperative quality of life (QOL) evaluated using the Postgastrectomy Syndrome Assessment Scale-45 was maintained, and the patient was still alive 8 months after the CS without recurrence. CONCLUSIONS: An sTG with a small remnant stomach might be clinically useful for preventing a decline in QOL and improving prognoses in patients with stage IV gastric cancer after chemotherapy.

MicroRNA-20a in extracellular vesicles derived from duodenal fluid is a possible biomarker for pancreatic ductal adenocarcinoma.

Background: Pancreatic ductal adenocarcinoma (PDAC) has a high mortality rate owing to its late diagnosis and aggression. In addition, there are relatively few minimally invasive screening methods for the early detection of PDAC, making the identification of biomarkers for this disease a critical priority. Recent studies have reported that microRNAs in extracellular vesicles (EV-miRs) from bodily fluids can be useful for the diagnosis of PDACs. Given this, we designed this study to evaluate the utility of cancer EVs extracted from duodenal fluid (DF) and their resident EV-miRs as potential biomarkers for the detection of PDAC. Methods: EV-miRs were evaluated and identified in the supernatants of various pancreatic cancer cell lines (Panc-1, SUIT2, and MIAPaca2), human pancreatic duct epithelial cells, and the DF from patients with PDAC and healthy controls. EVs were extracted using ultracentrifugation and the relative expression of EV-miR-20a was quantified. Results: We collected a total of 34 DF samples (27 PDAC patients and seven controls) for evaluation and our data suggest that the relative expression levels of EV-miR-20a were significantly higher in patients with PDAC than in controls (p = 0.0025). In addition, EV-miR-20a expression could discriminate PDAC from control patients regardless of the location of the tumor with an area under the curve values of 0.88 and 0.88, respectively. Conclusions: We confirmed the presence of EVs in the DF and suggest that the expression of EV-miR-20a in these samples may act as a potential diagnostic biomarker for PDAC.

Higher incidence of cholelithiasis with Roux-en-Y reconstruction compared with Billroth-I after laparoscopic distal gastrectomy for gastric cancer: a retrospective cohort study.

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/m2, 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.

International evidence-based Kyoto guidelines for the management of intraductal papillary mucinous neoplasm of the pancreas.

This study group aimed to revise the 2017 international consensus guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, and mainly focused on five topics; the revision of high-risk stigmata (HRS) and worrisome features (WF), surveillance of non-resected IPMN, surveillance after resection of IPMN, revision of pathological aspects, and investigation of molecular markers in cyst fluid. A new development from the prior guidelines is that systematic reviews were performed for each one of these topics, and published separately to provide evidence-based recommendations. One of the highlights of these new "evidence-based guidelines" is to propose a new management algorithm, and one major revision is to include into the assessment of HRS and WF the imaging findings from endoscopic ultrasound (EUS) and the results of cytological analysis from EUS-guided fine needle aspiration technique, when this is performed. Another key element of the current guidelines is to clarify whether lifetime surveillance for small IPMNs is required, and recommends two options, "stop surveillance" or "continue surveillance for possible development of concomitant pancreatic ductal adenocarcinoma", for small unchanged BD-IPMN after 5 years surveillance. Several other points are also discussed, including identifying high-risk features for recurrence in patients who underwent resection of non-invasive IPMN with negative surgical margin, summaries of the recent observations in the pathology of IPMN. In addition, the emerging role of cyst fluid markers that can aid in distinguishing IPMN from other pancreatic cysts and identify those IPMNs that harbor high-grade dysplasia or invasive carcinoma is discussed.

Comparison of the subtotal and narrow gastric conduit for cervical esophagogastrostomy after esophagectomy in esophageal cancer patients: a propensity score-matched analysis.

BACKGROUND: Several reports have compared narrow gastric conduit (NGC) with subtotal gastric conduit (SGC) for cervical esophagogastrostomy after esophagectomy; however, whether which one is more beneficial in terms of postoperative complications remains unclear. To determine the optimal gastric conduit type, we retrospectively investigated and compared the postoperative complications between NGC and SGC used in cervical circular-tapered esophagogastrostomy after esophagectomy through a propensity score-matched analysis. METHODS: Between 2008 and 2022, 577 consecutive esophageal cancer patients who underwent esophagectomy and cervical circular-stapled esophagogastrostomy were enrolled in this study. RESULTS: Of the 577 patients, 77 were included each in the SGC and NGC groups, after propensity score matching. Clinical characteristics did not differ between the two groups. The anastomotic leakage rate was significantly lower in the SGC group than in the NGC group (5% vs. 22%, p < 0.01). The anastomotic stenosis rate was significantly higher in the SGC group (16% vs. 5%, p = 0.03). Multivariate logistic analysis showed that NGC, subcutaneous route, and age were significant independent factors associated with anastomotic leakage (odds ratios, 8.58, 6.49, and 5.21; p < 0.01, < 0.01 and 0.03, respectively) and that SGC was a significant independent factor associated with anastomotic stricture (odds ratios, 4.91; p = 0.04). CONCLUSIONS: In cervical circular-stapled esophagogastrostomy after esophagectomy, SGC was superior to NGC in terms of reducing the risk of anastomotic leakage, although the risk of anastomotic stricture needs to be resolved.

Evaluation of Quality of Life and Prognosis of Gastric Cancer Patients After Laparoscopic Subtotal Gastrectomy.

BACKGROUND/AIM: The clinical significance of laparoscopic subtotal gastrectomy (LsTG) with a small remnant stomach remains unclear in patients with gastric cancer, including at an advanced stage. The present study assessed postoperative quality of life (QOL) and survival after LsTG compared with laparoscopic total gastrectomy (LTG). PATIENTS AND METHODS: We retrospectively analyzed consecutive patients with gastric cancer who underwent LsTG (n=26) or LTG (n=26). Surgical outcome, postoperative nutritional status, QOL, and prognosis were compared between the LsTG and LTG groups. The Postgastrectomy Syndrome Assessment Scale was used to evaluate postoperative QOL. RESULTS: Operating time was significantly shorter (p<0.01) and postoperative morbidity was significantly lower (p=0.04) in the LsTG than in the LTG group. The reduction in body weight after surgery was significantly greater in the LTG than in the LsTG group (p<0.01). The Postgastrectomy Syndrome Assessment Scale revealed that, compared with LTG, LsTG significantly improved postoperative QOL (p<0.05). There was no significant difference in relapse-free survival and cancer-specific survival between the two groups. Three patients in the LTG group died of pneumonia and overall survival was significantly longer in the LsTG group (p=0.01). CONCLUSION: This study demonstrated the efficacy of LsTG with a small remnant stomach to prevent a decline in postoperative QOL and non-cancer-related death.

Feasibility of Surveillance for Mucinous Cystic Neoplasm of the Pancreas: A Multi-Institutional Retrospective Study of 328 Patients by the Japanese Pancreatic Society.

OBJECTIVE: We aimed to elucidate the feasibility of surveillance of patients with mucinous cystic neoplasm (MCN). METHODS: We performed a retrospective, multi-institutional study of 328 patients who underwent surgery for MCN at 18 Japanese institutions. Patients with MCN were divided into an immediate surgery group and a surveillance group, which underwent surgery after surveillance. RESULTS: The median surveillance period until surgery in the surveillance group was 27 months (range, 7-165 months). Compared with the immediate surgery group, the surveillance group showed smaller tumor diameter (46 vs 50 mm, P = 0.01), more frequent laparoscopic approach (58% vs 37%, P < 0.01), and less frequent malignancy (7% vs 15%, P = 0.03). The new appearance of mural nodules and elevation of serum tumor markers were associated with malignancy in the surveillance group. Two patients in the surveillance group experienced postoperative recurrence, although there was no significant difference in recurrence or disease-free survival between the two groups. In the surveillance group, the 1-, 5-, and 10-year cumulative incidence rates of malignant MCN were 0.8%, 5.6%, and 36.5%, respectively. CONCLUSION: As the risk of progression to malignant MCNs increases over the long term, MCNs should be resected rather than subjected to unnecessary surveillance.

Impact of antithrombotic therapy on postpancreatectomy hemorrhage in 7116 patients: A project study by the Japanese Society of Hepato-Biliary-Pancreatic Surgery.

BACKGROUND: We previously reported an association between antithrombotic therapy and an increased risk of postpancreatectomy hemorrhage (PPH). To validate our findings, we conducted a large-scale multicenter retrospective study from 63 high-volume centers in Japan. METHODS: Between 2015 and 2018, 7116 patients who underwent pancreatectomy were enrolled. The antithrombotic group consisted of 920 patients (12.9%) who received preoperative antithrombotic agents including aspirin, clopidogrel, ticlopidine, prasugrel, warfarin, and direct oral anticoagulants. RESULTS: PPH occurred in 235 (3.3%) of the patients. The incidence of PPH and mortality were significantly higher in the antithrombotic group than in the control group (5.7 vs. 3.0% and 2.2 vs. 0.9%, respectively; both p < .001). In multivariate analysis, a history of antithrombotic use was an independent risk factor for grade C PPH (p = .036). In the antithrombotic group, PPH tended to be delayed in the patients with restarting antithrombotic therapy. Notably, the occurrence of delayed PPH after restarting antithrombotic therapy was observed only when antithrombotic therapy was restarted within 10 days after pancreatectomy. CONCLUSIONS: This multicenter study demonstrated that a history of antithrombotic use was a significant risk factor for PPH and mortality. In particular, the resumption of antithrombotic therapy in the early postoperative period should be done with caution.

Oncogenic Targets Regulated by Tumor-Suppressive miR-30c-1-3p and miR-30c-2-3p: TRIP13 Facilitates Cancer Cell Aggressiveness in Breast Cancer.

Accumulating evidence suggests that the miR-30 family act as critical players (tumor-suppressor or oncogenic) in a wide range of human cancers. Analysis of microRNA (miRNA) expression signatures and The Cancer Genome Atlas (TCGA) database revealed that that two passenger strand miRNAs, miR-30c-1-3p and miR-30c-2-3p, were downregulated in cancer tissues, and their low expression was closely associated with worse prognosis in patients with BrCa. Functional assays showed that miR-30c-1-3p and miR-30c-2-3p overexpression significantly inhibited cancer cell aggressiveness, suggesting these two miRNAs acted as tumor-suppressors in BrCa cells. Notably, involvement of passenger strands of miRNAs is a new concept of cancer research. Further analyses showed that seven genes (TRIP13, CCNB1, RAD51, PSPH, CENPN, KPNA2, and MXRA5) were putative targets of miR-30c-1-3p and miR-30c-2-3p in BrCa cells. Expression of seven genes were upregulated in BrCa tissues and predicted a worse prognosis of the patients. Among these genes, we focused on TRIP13 and investigated the functional significance of this gene in BrCa cells. Luciferase reporter assays showed that TRIP13 was directly regulated by these two miRNAs. TRIP13 knockdown using siRNA attenuated BrCa cell aggressiveness. Inactivation of TRIP13 using a specific inhibitor prevented the malignant transformation of BrCa cells. Exploring the molecular networks controlled by miRNAs, including passenger strands, will facilitate the identification of diagnostic markers and therapeutic target molecules in BrCa.

Clinical significance of intraperitoneal paclitaxel combined with systemic chemotherapy for gastric cancer with peritoneal metastasis.

BACKGROUND: Despite investigations of intraperitoneal paclitaxel as a personalized treatment for peritoneal metastasis of gastric cancer, few studies have evaluated its prognostic impact on conversion surgery for unresectable gastric cancer with peritoneal metastasis. Our study aimed to close this gap in knowledge. METHODS: We retrospectively enrolled 128 patients who underwent chemotherapy for peritoneal metastasis from gastric cancer and assigned them into intraperitoneal (IP) (n = 36) and non-IP (n = 92) groups, based on the use of intraperitoneal paclitaxel plus systemic chemotherapy. RESULTS: Disease control rates were 94% and 69% in the IP and non-IP groups, respectively, with the former having a significantly higher tumor response rate than the latter (p < 0.01). The median survival times in the IP and non-IP groups were 665 and 359 days, respectively, with the former having significantly better prognosis than the latter (p = 0.02). Fifteen (42%) and sixteen (17%) patients underwent conversion surgery after chemotherapy in the IP and non-IP groups, respectively, with the former having a significantly higher conversion surgery induction rate than the latter (p < 0.01). Although the prognosis of the conversion surgery group was significantly better than that of the non-conversion surgery group (p < 0.01), there was no significant difference in prognosis between patients in the IP and non-IP groups who underwent conversion surgery (p = 0.22). Multivariate analysis identified performance status and conversion surgery as independent prognostic factors (all p < 0.01). CONCLUSION: Our study demonstrated that the IP chemotherapy was one of important factors for conversion surgery induction, while it was not a risk factor for prognosis.

Metal-free laparoscopic distal pancreatectomy using transpancreatic mattress suture with polyglycolic acid sheet and fibrin glue: A case report.

Laparoscopic distal pancreatectomy (LDP) is the standard surgery for malignant and premalignant tumors of the pancreatic body and tail. A stapler is commonly used to close the pancreatic stump due to its simplicity; however, the use of a stapler is associated with the risk of metal allergy and postoperative pancreatic fistula, especially in thick pancreases. Here, we present a case of LDP without metal instruments, including staplers and clips, in a 54-year-old woman with a metal allergy and a thick pancreas. The pancreatic stump was closed using the transpancreatic mattress suture method with a polyglycolic acid sheet (PGA) and fibrin glue. The postoperative course was uneventful. Metal-free LDP is useful and can be adopted regardless of the patient's background, such as a metal allergy or pancreatic thickness.

Transanal Total Mesorectal Excision Considering the Embryology Along the Fascia in Rectal Cancer Patients.

BACKGROUND/AIM: Transanal total mesorectal excision (TaTME) remains a challenging technique for rectal dissection. This study aimed to evaluate the clinical and oncological outcomes of TaTME, compared to those of the laparoscopic TME (LaTME) in rectal cancer. PATIENTS AND METHODS: Using propensity score-matched analyses, we analyzed retrospective data from 134 consecutive patients with rectal cancer who underwent TaTME or LaTME from January 2011 to June 2020 in our hospital. Clinical and oncological outcomes were evaluated. The primary endpoint was the 2-year local recurrence rate. RESULTS: Before data analysis, significant group-dependent differences were observed only in the tumor height (p<0.01). After analysis, preoperative patient demographics were similar between the TaTME and LaTME groups. The operative time was significantly shorter in the TaTME group (p=0.02), and the rates of hand-sewn anastomosis and protective loop ileostomy were significantly higher (p<0.01). The TaTME group showed a null conversion to open surgery compared to the LaTME group (5.9%). The postoperative complications, including anastomotic leak, were comparable between the two groups. However, the rate of Clavien-Dindo grade III tended to be lower in the TaTME group (p=0.07). There were no statistically significant differences in terms of pathological findings, and the 2-year local recurrence rate was similar between the two groups (both 5.9%). CONCLUSION: TaTME based on embryology along the fascia is feasible and seems a safe alternative to LaTME in selected patients with rectal cancer when considering the conversion rate and the operative time.

Modified pull-through coloanal anastomosis to avoid permanent stomas and reduce postoperative complications for lower rectal tumors.

BACKGROUND: We performed pull-through hand-sewn coloanal anastomosis immediately after sphincter-preserving ultralow anterior resection (ULAR) [pull-through ultra (PTU)] to avoid permanent stoma and reduce postoperative complications of lower rectal tumors. This study aimed to compare the clinical outcomes of PTU versus non-PTU (stapled or hand-sewn coloanal anastomosis with diverting stoma) after sphincter-preserving ULAR for lower rectal tumors. METHODS: This retrospective cohort study analyzed prospectively maintained data from 100 consecutive patients who underwent PTU (n = 29) or non-PTU (n = 71) after sphincter-preserving ULAR for rectal tumors between January 2011 and March 2023. In PTU, hand-sewn coloanal anastomosis was immediately performed using 16 stitches of 4-0 monofilament suture during primary surgery. The clinical outcomes were assessed. The primary outcomes were rates of permanent stomas and overall postoperative complications. RESULTS: The PTU group was significantly less likely to require a permanent stoma than the non-PTU group (P < 0.01). None of the patients in the PTU group required permanent stoma and the rate of overall complications was significantly lower in the PTU group (P = 0.01). The median operative time was comparable between the two groups (P = 0.33) but the median operative time during the second stage was significantly shorter in the PTU group (P < 0.01). The rates of anastomotic leakage and complications of Clavien-Dindo grade III were comparable between the two groups. Diverting ileostomy was performed in two patients with an anastomotic leak in the PTU group. The PTU group was significantly less likely to require a diverting ileostomy than those in the non-PTU group (P < 0.01). The composite length of hospital stay was significantly shorter in the PTU group (P < 0.01). CONCLUSIONS: PTU via immediate coloanal anastomosis for lower rectal tumors is a safe alternative to the current sphincter-preserving ULAR with diverting ileostomy for patients who wish to avoid a stoma.

Clinical Significance of Recurrence Risk Score for Conversion Surgery in Patients With Advanced Gastric Cancer.

BACKGROUND/AIM: To develop a recurrence risk score for determining the clinical indication for adjuvant chemotherapy in patients with initially unresectable advanced gastric cancer who underwent conversion surgery after chemotherapy. PATIENTS AND METHODS: A total of 65 patients with stage IV gastric cancer who underwent conversion surgery after chemotherapy were retrospectively enrolled. We established a risk score based on clinicopathological factors related to recurrence after conversion surgery. RESULTS: Out of 65 patients, 40 (62%) had recurrence after conversion surgery. The 5-year overall survival rates in patients with and without recurrence were 14.4% and 87.1%, respectively (p<0.01). Multivariate logistic regression analysis identified the depth of tumor invasion (pT2-4) and histological tumor response (grade 0-1a) as an independent risk factor for disease recurrence (p=0.033 and p=0.048, respectively). A scoring system determined by these two factors was created; total score ranged from 0 to 2 points, and patients were categorized into three groups (scores of 0 vs. 1 vs. 2 points). This scoring system showed that 12 (18%), 15 (23%), and 38 (58%) patients had recurrence risk scores of 0, 1, and 2 points, respectively. There was a close relationship between a high score and the presence of tumor recurrence (p<0.01). Moreover, our model system had a high sensitivity for the prediction of recurrence, compared with the pathological stage. CONCLUSION: Recurrence risk score is a promising tool for assessing the need for adjuvant chemotherapy in patients with initially unresectable advanced gastric cancer after conversion surgery.

Application of Machine Learning Analyses Using Clinical and [18F]-FDG-PET/CT Radiomic Characteristics to Predict Recurrence in Patients with Breast Cancer.

PURPOSE: To develop and identify machine learning (ML) models using pretreatment clinical and 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography ([18F]-FDG-PET)-based radiomic characteristics to predict disease recurrences in patients with breast cancers who underwent surgery. PROCEDURES: This retrospective study included 112 patients with 118 breast cancer lesions who underwent [18F]-FDG-PET/ X-ray computed tomography (CT) preoperatively, and these lesions were assigned to training (n=95) and testing (n=23) cohorts. A total of 12 clinical and 40 [18F]-FDG-PET-based radiomic characteristics were used to predict recurrences using 7 different ML algorithms, namely, decision tree, random forest (RF), neural network, k-nearest neighbors, naive Bayes, logistic regression, and support vector machine (SVM) with a 10-fold cross-validation and synthetic minority over-sampling technique. Three different ML models were created using clinical characteristics (clinical ML models), radiomic characteristics (radiomic ML models), and both clinical and radiomic characteristics (combined ML models). Each ML model was constructed using the top ten characteristics ranked by the decrease in Gini impurity. The areas under ROC curves (AUCs) and accuracies were used to compare predictive performances. RESULTS: In training cohorts, all 7 ML algorithms except for logistic regression algorithm in the radiomics ML model (AUC = 0.760) achieved AUC values of >0.80 for predicting recurrences with clinical (range, 0.892-0.999), radiomic (range, 0.809-0.984), and combined (range, 0.897-0.999) ML models. In testing cohorts, the RF algorithm of combined ML model achieved the highest AUC and accuracy (95.7% (22/23)) with similar classification performance between training and testing cohorts (AUC: training cohort, 0.999; testing cohort, 0.992). The important characteristics for modeling process of this RF algorithm were radiomic GLZLM_ZLNU and AJCC stage. CONCLUSIONS: ML analyses using both clinical and [18F]-FDG-PET-based radiomic characteristics may be useful for predicting recurrence in patients with breast cancers who underwent surgery.

Mucosectomy of the anal canal via transanal minimally invasive surgery combined with transanal total mesorectal excision for familial adenomatous polyposis: A technical note.

AIM: Total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the standard surgical treatment modality for familial adenomatous polyposis (FAP). It is challenging to perform proctectomy and preserve anal sphincter function. In this video, precise mucosectomy of the anal canal via transanal minimally invasive surgery (MAC-TAMIS) is reported. METHODS: An asymptomatic 35-year-old man was found to have a positive faecal occult blood test in routine screening examination and was diagnosed with FAP on colonoscopic examination. The patient was scheduled for total proctocolectomy with IPAA using the TAMIS approach combined with transanal total mesorectal excision. MAC-TAMIS was performed to preserve the internal anal sphincter during laparoscopy. RESULTS: The total duration of surgery was 543 min, blood loss was minimal, and the postoperative course was uneventful. The postoperative hospital stay was 12 days. The pathological findings demonstrated no evidence of malignancy. Gastrographic imaging from the ileostomy showed sufficient size of the J pouch and good tonus of the anus at 6 months after surgery. The Wexner scores at 1, 3 and 6 months after ileostomy closure were 5, 3 and 0, respectively. CONCLUSION: The MAC-TAMIS technique is safe and feasible during total proctocolectomy with IPAA in patients with FAP. This technique allows us to precisely preserve the internal anal sphincter using a laparoscopic approach.