Federated 3D multi-organ segmentation with partially labeled and unlabeled data.

PURPOSE: This paper considers a new problem setting for multi-organ segmentation based on the following observations. In reality, (1) collecting a large-scale dataset from various institutes is usually impeded due to privacy issues; (2) many images are not labeled since the slice-by-slice annotation is costly; and (3) datasets may exhibit inconsistent, partial annotations across different institutes. Learning a federated model from these distributed, partially labeled, and unlabeled samples is an unexplored problem. METHODS: To simulate this multi-organ segmentation problem, several distributed clients and a central server are maintained. The central server coordinates with clients to learn a global model using distributed private datasets, which comprise a small part of partially labeled images and a large part of unlabeled images. To address this problem, a practical framework that unifies partially supervised learning (PSL), semi-supervised learning (SSL), and federated learning (FL) paradigms with PSL, SSL, and FL modules is proposed. The PSL module manages to learn from partially labeled samples. The SSL module extracts valuable information from unlabeled data. Besides, the FL module aggregates local information from distributed clients to generate a global statistical model. With the collaboration of three modules, the presented scheme could take advantage of these distributed imperfect datasets to train a generalizable model. RESULTS: The proposed method was extensively evaluated with multiple abdominal CT datasets, achieving an average result of 84.83% in Dice and 41.62 mm in 95HD for multi-organ (liver, spleen, and stomach) segmentation. Moreover, its efficacy in transfer learning further demonstrated its good generalization ability for downstream segmentation tasks. CONCLUSION: This study considers a novel problem of multi-organ segmentation, which aims to develop a generalizable model using distributed, partially labeled, and unlabeled CT images. A practical framework is presented, which, through extensive validation, has proved to be an effective solution, demonstrating strong potential in addressing this challenging problem.

Novel Repair Technique for Oral and Anal Side Stoma Prolapse of a Loop Colostomy With the Stapled Modified Altemeier Method Using Indocyanine Green Fluorescence Imaging.

BACKGROUND/AIM: Stoma prolapse is a common complication in the late phase after stoma creation. With advances in chemotherapy, a double-orifice colostomy or ileostomy and chemotherapy are used to treat primary unresectable colorectal cancer. Preoperative therapy with a double-orifice colostomy or ileostomy is performed to aid primary colorectal cancer miniaturization. Therefore, the number of stoma prolapses will likely increase in the future. Previous reports on the repair of stoma prolapse focused on unilateral stoma prolapse of loop colostomy, and there are no reports about the bilateral stoma prolapse of loop colostomy or ileostomy. CASE REPORT: We report a novel repair technique for oral and anal side (bilateral) stoma prolapse of a loop colostomy with the stapled modified Altemeier method using indocyanine green (ICG) fluorescence imaging considering the distribution of marginal artery in preventing marginal artery injury which has considerable clinical significance. CONCLUSION: Our novel technique for the oral and anal side prolapse of a loop colostomy is considered effective and safe.

A multi-institutional prospective observational study to compare postoperative quality of life of patients who undergo total or proximal gastrectomy for early gastric cancer (CCOG1602).

BACKGROUND: Proximal gastrectomy (PG) has become an increasingly preferred procedure for treating early cancer in the upper third of the stomach. However, advantages of PG in postoperative quality of life (QOL) over total gastrectomy (TG) has not fully proven. METHODS: We conducted a multi-institutional prospective observational study (CCOG1602) of patients who undergo TG or PG for cStage I gastric cancer. We used the PGSAS-37 and EORTC-QLQ-C30 to evaluate the changes in body weight and QOL over a 3-year postoperative period. The primary endpoint was the weight loss rate 3 years after surgery. RESULTS: We enrolled 109 patients from 18 institutions and selected 65 and 19 patients for inclusion in the TG and PG groups, respectively. Mean postoperative weight loss rates were 16.0% and 11.7% for the TG and PG groups, respectively (p = 0.056, Cohen's d 0.656) during postoperative year 1% and 15.0% and 10.8% for TG and PG (p = 0.068, Cohen's d 0.543), respectively, during postoperative year 3, indicating that the PG group achieved a better trend with a moderate effect size. According to the PGSAS-37, the PG group experienced a better trend in the indigestion subscale (p < 0.001, Cohen's d -1.085) and total symptom score (p = 0.050, Cohen's d -0.59) during postoperative year 3 compared with the TG group. In contrast, the EORTC-QLQ-C30 detected no difference between the groups at any time point during 3-year postoperative period. CONCLUSIONS: This prospective study demonstrates that PG tended to be more favorable compared with TG with respect to postoperative weight loss and QOL, particularly regarding indigestion.

5-year follow-up results of a JCOG1104 (OPAS-1) phase III non-inferiority trial to compare 4 courses and 8 courses of S-1 adjuvant chemotherapy for pathological stage II gastric cancer.

BACKGROUND: Postoperative adjuvant chemotherapy with S-1 for 1 year (corresponding to eight courses) is the standard treatment for pathological stage II gastric cancer. The phase III trial (JCOG1104) investigating the non-inferiority of four courses of S-1 to eight courses was terminated due to futility at the first interim analysis. To confirm the primary results, we reported the results after a 5-years follow-up in JCOG1104. METHODS: Patients histologically diagnosed with stage II gastric cancer after radical gastrectomy were randomly assigned to receive S-1 for eight or four courses. In detail, 80 mg/m2/day S-1 was administered for 4 weeks followed by a 2-week rest as a single course. RESULTS: Between February 16, 2012, and March 19, 2017, 590 patients were enrolled and randomly assigned to 8-course (295 patients) and 4-course (295 patients) regimens. After a 5-years follow-up, the relapse-free survival at 3 years was 92.2% for the 8-course arm and 90.1% for the 4-course arm, and that at 5 years was 87.7% for the 8-course arm and 85.6% for the 4-course arm (hazard ratio 1.265, 95% CI 0.846-1.892). The overall survival at 3 years was 94.9% for the 8-course arm, 93.2% for the 4-course arm, and that at 5 years was 89.7% for the 8-course arm, and 88.6% for the 4-course arm (HR 1.121, 95% CI 0.719-1.749). CONCLUSIONS: The survival of the four-course arm was slightly but consistently inferior to that of the eight-course arm. Eight-course S-1 should thus remain the standard adjuvant chemotherapy for pathological stage II gastric cancer.

Endoscope Automation Framework with Hierarchical Control and Interactive Perception for Multi-Tool Tracking in Minimally Invasive Surgery.

In the context of Minimally Invasive Surgery, surgeons mainly rely on visual feedback during medical operations. In common procedures such as tissue resection, the automation of endoscopic control is crucial yet challenging, particularly due to the interactive dynamics of multi-agent operations and the necessity for real-time adaptation. This paper introduces a novel framework that unites a Hierarchical Quadratic Programming controller with an advanced interactive perception module. This integration addresses the need for adaptive visual field control and robust tool tracking in the operating scene, ensuring that surgeons and assistants have optimal viewpoint throughout the surgical task. The proposed framework handles multiple objectives within predefined thresholds, ensuring efficient tracking even amidst changes in operating backgrounds, varying lighting conditions, and partial occlusions. Empirical validations in scenarios involving single, double, and quadruple tool tracking during tissue resection tasks have underscored the system's robustness and adaptability. The positive feedback from user studies, coupled with the low cognitive and physical strain reported by surgeons and assistants, highlight the system's potential for real-world application.

Three cases of open surgical procedures on ileal conduits for the repair of benign ureteroenteric anastomotic strictures after total pelvic exenteration of rectal tumors.

Ureteroenteric anastomotic strictures (UEAS) are typical complications after creating an ileal conduit for total pelvic exenteration (TPE) of rectal tumors. We report the ileal conduit for reconstruction in three patients, in the age-range of 47-73 years. Case 1 was when a left-sided UEAS had sufficient length of ureter for anastomosis, Case 2 was a right-sided UEAS with sufficient length of ureter for anastomosis, and Case 3 was a left-sided UEAS with insufficient length of ureter for anastomosis. There were no complications after operation and no recurrence of UEAS. It is important to learn the open surgical procedures for repair of a benign UEAS after TPE of rectal cancers. This has fewer complications and is safe in the long term.

How many times can patients tolerate reoperation for the local recurrence of colorectal cancer in terms of complications?

The frequency of resection for the recurrence of colorectal cancer has not been investigated in previous studies. Likewise, the related postoperative complications and the limit for indicating surgical resection has not been reported. Herein, we reported the complications of a highly frequent surgical approach for rectal cancer recurrence, i.e., exceeding three reoperations, based on our clinical experience. We included 15 cases exceeding two operations for the local recurrence of colorectal cancer from 2014 to 2019. We examined the postoperative complications classified as Clavien?Dindo IIIb. The positive rates of the complications were 0 (0.0%), 0 (0.0%), 2 (13.3%), 3 (37.5%), and 0 (0.0%) for the primary, 1st recurrent, 2nd recurrent, 3rd recurrent, and 4th recurrent operation group (p=0.027), respectively. It is important to exercise caution in handling cases exceeding two reoperations (exceeding three reoperations including the primary operation). J. Med. Invest. 70 : 369-376, August, 2023.

Novel Ureteral Stent Catheterization Technique for Treating Hyperchloremic Metabolic Acidosis After Total Pelvic Exenteration.

BACKGROUND/AIM: Hyperchloremic metabolic acidosis after total pelvic exenteration (TPE) is relatively rare. Urinary diversion of the ileal conduit during TPE can result in increased urine reabsorption leading to hyperchloremic metabolic acidosis. We developed a new technique for the retrograde catheterization of a ureteral stent into an ileal conduit to treat hyperchloremic metabolic acidosis. CASE REPORT: A 70-year-old man underwent TPE for locally recurrent rectal cancer. Multiple episodes of complications, such as hyperchloremia and metabolic acidosis, occurred. Effective drainage of urine from the ileal conduit is crucial. With collaboration between an endoscopist and a radiologist, we developed a novel method for retrograde catheterization of the ureteral stent into an ileal conduit for hyperchloremic metabolic acidosis after TPE. The patient's condition quickly improved after the procedure. CONCLUSION: Our novel technique of retrograde catheterization of a ureteral stent into an ileal conduit for hyperchloremic metabolic acidosis could be adopted worldwide, as it is effective and safe.

Effect of Four Main Gastrectomy Procedures for Proximal Gastric Cancer on Patient Quality of Life: A Nationwide Multi-Institutional Study.

PURPOSE: This study aimed to examine the effects of 4 main types of gastrectomy for proximal gastric cancer on postoperative symptoms, living status, and quality of life (QOL) using the Postgastrectomy Syndrome Assessment Scale-45 (PGSAS-45). MATERIALS AND METHODS: We surveyed 1,685 patients with upper one-third gastric cancer who underwent total gastrectomy (TG; n=1,020), proximal gastrectomy (PG; n=518), TG with jejunal pouch reconstruction (TGJP; n=93), or small remnant distal gastrectomy (SRDG; n=54). The 19 main outcome measures (MOMs) of the PGSAS-45 were compared using the analysis of means (ANOM), and the general QOL score was calculated for each gastrectomy type. RESULTS: Patients who underwent TG experienced the lowest postoperative QOL. ANOM showed that 10 MOMs were worse in patients with TG. Four MOMs improved in patients with PG, while 1 worsened. One MOM was improved in patients with TGJP versus 8 MOMs in patients with SRDG. The general QOL scores were as follows: SRDG (+39 points), TGJP (+6 points), PG (+3 points), and TG (-1 point). CONCLUSIONS: The TG group experienced the greatest decline in postoperative QOL. SRDG and PG, which preserve part of the stomach without compromising curability, and TGJP, which is used when TG is required, enhance the postoperative QOL of patients with proximal gastric cancer. When selecting the optimal gastrectomy method, it is essential to understand the characteristics of each and actively incorporate guidance to improve postoperative QOL.

Five-Year Survival Outcomes of Laparoscopy-Assisted vs Open Distal Gastrectomy for Advanced Gastric Cancer: The JLSSG0901 Randomized Clinical Trial.

Importance: Evidence of implementation of laparoscopic gastrectomy for locally advanced gastric cancer is currently insufficient, as the primary end point in previous prospective studies was evaluated at a median follow-up time of 3 years. More robust evidence is necessary to verify noninferiority of laparoscopic gastrectomy. Objective: To compare 5-year survival outcomes between laparoscopy-assisted distal gastrectomy (LADG) and open distal gastrectomy (ODG) with D2 lymph node dissection for locally advanced gastric cancer. Design, Setting, and Participants: This was a multicenter, open-label, noninferiority, prospective randomized clinical trial. Between November 26, 2009, and July 29, 2016, eligible patients with histologically proven gastric carcinoma from 37 institutes in Japan were enrolled. Two interim analyses and final analysis were performed in October 2014, May 2018, and November 2021, respectively. Interventions: Patients were randomly assigned (1:1) to either the ODG or LADG group. The procedures were performed exclusively by qualified surgeons. Main Outcomes and Measures: The primary end point was 5-year relapse-free survival, and the noninferiority margin for the hazard ratio (HR) was set at 1.31. The secondary end points were 5-year overall survival and safety. Results: A total of 502 patients were included in the full-analysis set: 254 (50.6%) in the ODG group and 248 (49.4%) in the LADG group. Patients in the ODG group had a median (IQR) age of 67 (33-80) years and included 168 males (66.1%). Patients in the LADG group had a median (IQR) age of 64 (34-80) years and included 169 males (68.1%). No significant differences were observed in severe postoperative complications between the 2 groups in the safety analysis (ODG, 4.7% [11 of 233] vs LADG, 3.5% [8 of 227]; P = .64). The median (IQR) follow-up for all patients after randomization was 67.9 (60.3-92.0) months. The 5-year relapse-free survival was 73.9% (95% CI, 68.7%-79.5%) and 75.7% (95% CI, 70.5%-81.2%) for the ODG and LADG groups, respectively, and the HR was 0.96 (90% CI, 0.72-1.26; noninferiority 1-sided P = .03). Further, no significant difference was observed in overall survival time between the 2 groups, and the HR was 0.83 (95% CI, 0.57-1.21; P = .34). The pattern of recurrence was similar between the 2 groups. Conclusions and Relevance: Results of this study show that on the basis of 5-year follow-up data, LADG with D2 lymph node dissection for locally advanced gastric cancer, when performed by qualified surgeons, was proved noninferior to ODG. This laparoscopic approach could become a standard treatment for locally advanced gastric cancer. Trial Registration: UMIN Clinical Trial Registry: UMIN000003420.

A skeleton context-aware 3D fully convolutional network for abdominal artery segmentation.

PURPOSE: This paper aims to propose a deep learning-based method for abdominal artery segmentation. Blood vessel structure information is essential to diagnosis and treatment. Accurate blood vessel segmentation is critical to preoperative planning. Although deep learning-based methods perform well on large organs, segmenting small organs such as blood vessels is challenging due to complicated branching structures and positions. We propose a 3D deep learning network from a skeleton context-aware perspective to improve segmentation accuracy. In addition, we propose a novel 3D patch generation method which could strengthen the structural diversity of a training data set. METHOD: The proposed method segments abdominal arteries from an abdominal computed tomography (CT) volume using a 3D fully convolutional network (FCN). We add two auxiliary tasks to the network to extract the skeleton context of abdominal arteries. In addition, our skeleton-based patch generation (SBPG) method further enables the FCN to segment small arteries. SBPG generates a 3D patch from a CT volume by leveraging artery skeleton information. These methods improve the segmentation accuracies of small arteries. RESULTS: We used 20 cases of abdominal CT volumes to evaluate the proposed method. The experimental results showed that our method outperformed previous segmentation accuracies. The averaged precision rate, recall rate, and F-measure were 95.5%, 91.0%, and 93.2%, respectively. Compared to a baseline method, our method improved 1.5% the averaged recall rate and 0.7% the averaged F-measure. CONCLUSIONS: We present a skeleton context-aware 3D FCN to segment abdominal arteries from an abdominal CT volume. In addition, we propose a 3D patch generation method. Our fully automated method segmented most of the abdominal artery regions. The method produced competitive segmentation performance compared to previous methods.

Database-driven patient-specific registration error compensation method for image-guided laparoscopic surgery.

PURPOSE: A surgical navigation system helps surgeons understand anatomical structures in the operative field during surgery. Patient-to-image registration, which aligns coordinate systems between the CT volume and a positional tracker, is vital for accurate surgical navigation. Although a point-based rigid registration method using fiducials on the body surface is often utilized for laparoscopic surgery navigation, precise registration is difficult due to such factors as soft tissue deformation. We propose a method that compensates a transformation matrix computed using fiducials on the body surface based on the analysis of positional information in the database. METHODS: We built our database by measuring the positional information of the fiducials and the guidance targets in both the CT volume and positional tracker coordinate systems through previous surgeries. We computed two transformation matrices: using only the fiducials and using only the guidance targets in all the data in the database. We calculated the differences between the two transformation matrices in each piece of data. The compensation transformation matrix was computed by averaging these difference matrices. In this step, we selected the data from the database based on the similarity of the fiducials and the configuration of the guidance targets. RESULTS: We evaluated our proposed method using 20 pieces of data acquired during laparoscopic gastrectomy for gastric cancer. The locations of blood vessels were used as guidance targets for computing target registration error. The mean target registration errors significantly decreased from 33.0 to 17.1 mm before and after the compensation. CONCLUSION: This paper described a registration error compensation method using a database for image-guided laparoscopic surgery. Since our proposed method reduced registration error without additional intraoperative measurements during surgery, it increases the accuracy of surgical navigation for laparoscopic surgery.

Total Pelvic Exenteration Combined With Sacral Resection for Rectal Cancer.

BACKGROUND: This retrospective study aimed to demonstrate surgical operative approach of total pelvic exenteration combined with sacral resection with rectal cancer and elucidate the relationships between the level of sacral resection and short-term outcomes. METHODS: Twenty cases were selected. Data regarding sex, age, body mass index, neoadjuvant therapy, location of sacral resection ("Upper" or "Lower" relative to the level between the 3rd and 4th sacral segment), operative time, bleeding, and curability (R0/R1) were collected and compared to determine their association with complications exhibiting a Clavien-Dindo grade III. RESULTS: The complication rate was significantly higher for recurrent cancers (n = 10, 76.9%) than for primary cancers (n = 1, 14.3%) (P = .007), and for "Upper" resection (n = 8, 72.7%) than for "Lower" resection (n = 3, 33.3%) (P = .078). Significant differences were observed when complication rates for "Lower" and primary cancer resection (n = 3, .0%) were compared between "Upper" and recurrent cancers (n = 8, 100.0%) (P = .007). CONCLUSION: In patients with recurrent rectal cancer, "Upper" sacral resection during total pelvic exenteration is associated with a high complication rate, highlighting the need for careful monitoring.

Impact of tumor-related factors and inter-institutional heterogeneity on preoperative T staging for gastric cancer.

Background: To improve the diagnostic accuracy of preoperative T staging in gastric cancer, the authors evaluated tumor-related factors that might affect the diagnosis. Materials & methods: The authors analyzed the data of cT2-4b gastric cancer patients enrolled in the prospective, multicenter JCOG1302A study. They used contrast-enhanced computed tomography to analyze the association between tumor-related factors and the diagnostic accuracy of T3-4b staging for gastric cancer. Results: Among 876 cT3-4b tumors, the diagnostic accuracy was relatively low in the lower third of the stomach compared with those in the upper or middle. A multivariable analysis revealed that accuracy was higher in the lesser curvature or entire circumference region than in other areas (p < 0.001), in macroscopic types 3/5 than in types 0/1/2 (p = 0.003) and in the undifferentiated histological type than in the differentiated type (p = 0.011). Conclusion: The authors found tumor-related factors affecting preoperative T staging by enhanced computed tomography.

Additional chemotherapy before surgery is expected to have potentially beneficial effects on prognosis compared with chemotherapy only after surgery for advanced gastric cancer. The consideration of chemotherapy before surgery depends on preoperative diagnosis of the depth of tumor invasion in the stomach wall. Overdiagnosis of the depth of tumor invasion may lead to unnecessary administration of chemotherapy that is harmful to the patient. Tumor-related factors such as tumor location, macroscopic type and histological type may affect the diagnosis. Therefore, these factors should be considered with special care for the diagnosis, which may lead to higher accuracy in diagnosing the depth of tumor invasion in gastric cancer.

Validation study of a skill assessment tool for education and outcome prediction of laparoscopic distal gastrectomy.

BACKGROUND: The Japanese operative-rating scale for laparoscopic distal gastrectomy (JORS-LDG) was developed through cognitive task analysis together with the Delphi method to measure intraoperative performance during laparoscopic distal gastrectomy. This study aimed to investigate the value of this rating scale as an educational tool and a surgical outcome predictor in laparoscopic distal gastrectomy. METHODS: The surgical performance of laparoscopic distal gastrectomy was assessed by the first assistant, through self-evaluation in the operating room and by video raters blind to the case. We evaluated inter-rater reliability, internal consistency, and correlations between the JORS-LDG scores and the evaluation methods, patient characteristics, and surgical outcomes. RESULTS: Fifty-four laparoscopic distal gastrectomy procedures performed by 40 surgeons at 16 institutions were evaluated in the operating room and with video recordings using the proposed rating scale. The video inter-rater reliability was > 0.8. Participating surgeons were divided into the low, intermediate, and high groups based on their total scores. The number of laparoscopic surgeries and laparoscopic gastrectomy procedures performed differed significantly among the groups according to laparoscopic distal gastrectomy skill levels. The low, intermediate, and high groups also differed in terms of median operating times (311, 266, and 229 min, respectively, P < 0.001), intraoperative complication rates (27.8, 11.8, and 0%, respectively, P = 0.01), and postoperative complication rates (22.2, 0, and 0%, respectively, P = 0.002). CONCLUSIONS: The JORS-LDG is a reliable and valid measure for laparoscopic distal gastrectomy training and could be useful in predicting surgical outcomes.

Prognostic Significance of Intraoperative Peritoneal Lavage Cytology in Patients with Pancreatic Ductal Adenocarcinoma: A Single-Center Experience and Systematic Review of the Literature.

BACKGROUND: The prognostic significance of peritoneal lavage cytology (PLC) in patients with pancreatic ductal adenocarcinoma (PDAC) remains controversial. The purpose of this study was to evaluate the prognostic impact of PLC status in PDAC patients. METHODS: Patients intending to undergo resection for PDAC between 2007 and 2020 were included. Survival was compared among patients who underwent resection with negative or positive PLC status and those who did not undergo resection. Univariable and multivariable analyses were conducted to evaluate the prognostic impact of positive PLC status. A systematic literature review was performed to evaluate the correlation between prognosis and the positive PLC rate. RESULTS: A total of 480 patients formed the study cohort and were divided as follows: 438 in the negative PLC group, 18 in the positive PLC group, and 24 in the no resection group. Although the median survival time significantly differed between the negative and positive PLC groups (35.7 vs. 13.6 months, P < 0.001), it did not significantly differ between the positive PLC and no resection groups (13.6 vs. 12.2 months, P = 0.605). Multivariable analyses demonstrated that positive PLC status (hazard ratio = 3.54, 95% confidence interval = 1.97-6.38, P < 0.001) was the strongest poor prognostic factor. Based on statistical analyses for the systematic review, the prognostic impact of positive PLC status weakened significantly as the institutional positive PLC rate increased (P = 0.044). CONCLUSIONS: Resection did not improve the prognosis of patients with positive PLC status in our cohort. The institutional positive PLC rate may be a good reference for surgical indication in these patients.

A new option for laparoscopic spleen-preserving distal pancreatectomy: three cases with splenic artery preservation and resection of the splenic vein.

There are two techniques for a spleen-preserving distal pancreatectomy (SPDP): SPDP with splenic vessel preservation, and SPDP with splenic vessel resection. In some cases, although the splenic artery (SpA) can be preserved, the splenic vein (SpV) must be resected. We report the short- and long-term outcomes of three patients who underwent a new technique of laparoscopic SPDP with SpA preservation and SpV resection (SPDP-VRes). A grade B pancreatic fistula, which occurred in two patients, was successfully treated with drainage tube management. In all cases, the omental branches of the left gastroepiploic vein functioned as a drainage vein, and there was no splenomegaly, thrombocytopenia, or varix formation during the follow-up period (19 months to 5 years). Patients undergoing laparoscopic SPDP-VRes had no severe complications during the follow-up period; preserving the left omental branch is a key to this procedure. Laparoscopic SPDP-VRes might be a useful treatment option for patients undergoing SPDP.

Negative impact of intraoperative blood loss on long-term outcome after curative gastrectomy for advanced gastric cancer: exploratory analysis of the JCOG1001 phase III trial.

BACKGROUND: Recent retrospective studies have shown that increased intraoperative blood loss (IBL) during curative gastrectomy for patients with advanced gastric cancer is a negative prognostic indicator for recurrence. However, there are no reliable reports assessing this with a large-scale prospective cohort. This study aimed to evaluate the impact of IBL on long-term outcomes using data from the JCOG1001 phase III trial, which was designed to determine if bursectomy led to improved survival vs. nonbursectomy in patients with cT3/4a gastric cancer. METHODS: This study included 1203 of the 1204 patients enrolled in the JCOG1001. From the tertiles of IBL (196 ml, 400 ml), we divided the patients into three groups: IBL < 200 ml representing small blood loss (SBL, n = 404), 200 ml ≤ IBL < 400 ml representing medium blood loss (MBL, n = 393), and IBL ≥ 400 ml representing large blood loss (LBL, n = 406). The impact of IBL on relapse-free survival (RFS) was evaluated with univariable comparisons and multivariable Cox regression analyses. RESULTS: Three-year RFS after SBL, MBL, and LBL was 81.7%, 74.8%, and 70.6%, respectively. Multivariable analysis identified IBL, Eastern Cooperative Oncology Group performance status, pT, pN, and postoperative adjuvant chemotherapy as independent predictors of RFS. Compared with SBL as a reference, the hazard ratios of MBL and LBL were 1.461 (P = 0.012) and 1.520 (P = 0.009), respectively. CONCLUSIONS: Based on the analysis of data from a large-scale prospective study, an IBL of ≥ 200 ml after curative surgery for patients with cT3/4a gastric cancer was an independent predictor of reduced RFS.

Repair of antegrade anastomosis between ileal segment and amputated ureter for recurrent rectal cancer.

We describe a case of repair of the antegrade anastomosis between the "ileal segment" and amputated ureter for recurrent rectal cancer, in which some postoperative complications occurred but eventually resolved. If the length of the ureter is inadequate for end-to-end anastomosis, an ileal segment can be used as a conduit. This surgical technique is not difficult because an ileal conduit is typically created during total pelvic exenteration of rectal cancers. Therefore, anastomosing the ureter to an "ileal segment" is easy and feasible. Hence, we consider that knowledge of this technique would be beneficial for surgical oncologists who perform colorectal surgeries.

Aggressive and frequent resection of recurrences in retroperitoneal sarcoma contributes to long-term survival.

PURPOSE: Retroperitoneal sarcoma (RPS) is a rare tumor with a poor prognosis and is often undetected until it is significantly enlarged. While surgical resection remains the primary treatment, there is little research on its benefits, especially that concerning the reoperation of recurrent disease. This study investigated the impact of surgical procedures, especially reoperation of recurrent RPS, on prognosis. METHODS: This retrospective study included 51 patients who underwent radical resection surgery (R0 status) for primary or recurrent RPS without distant metastasis. Patient outcomes and prognosis were defined in terms of the clinicopathologic factors and surgical techniques performed. RESULTS: In all cases, the 5-year disease-free survival (DFS) rate was 28.2%, 5-year overall survival rate was 89.9%, and 5-year no residual liposarcoma rate was 54.3% after operation and re-reoperation. There was a statistically significant difference between the 5-year DFS rate and 5-year no residual liposarcoma rate due to frequent re-reoperation (p = 0.011). On univariate analysis of primary and recurrent lesions, the histological type and the number of organs involved were identified as statistically significant prognostic factors. Patients with well-differentiated liposarcomas had a statistically better prognosis than those with other cancer types (primary RPS, p = 0.028; recurrence, p = 0.024). CONCLUSIONS: Aggressive and frequent resection of recurrent RPS with combined resection of adjacent organs contributes to long-term survival. The establishment of a surgical strategy for RPS will require a prospective study.