Preoperative factors associated with lateral lymph node metastasis in lower rectal cancer and the evaluation of the middle rectal artery.

PURPOSE: This study aimed to identify cases in which lateral lymph node (LLN) dissection (LLND) can be excluded by clarifying preoperative factors, including an evaluation of the middle rectal artery (MRA), associated with LLN metastasis. METHODS: Fifty-five consecutive patients who underwent preoperative positron emission tomography-computed tomography (PET/CT) and total mesorectal excision with LLND for rectal cancer were included. We retrospectively investigated the preoperative clinical factors associated with pathological LLN (pLLN) metastasis. We analyzed the regions of pLLN metastasis using MRA. RESULTS: pLLN metastasis occurred in 13 (23.6%) patients. According to a multivariate analysis, clinical LLN (cLLN) metastasis based on short-axis size and LLN status based on PET/CT were independent preoperative factors of pLLN metastasis. The negative predictive value (NPV) was high (97.1%) in patients evaluated as negative based on PET/CT and cLLN short-axis size. MRA was detected in 24 patients (43.6%) using contrast-enhanced CT, and there was a significant relationship between pLLN metastasis and the presence of MRA. pLLN metastasis in the internal iliac region but not in the obturator region was significantly correlated with the presence of MRA. CONCLUSION: Combined cLLN metastasis based on short-axis size and PET/CT showed a higher NPV, suggesting this to be a useful method for identifying cases in which LLND can be excluded.

Damage to the Descending Colon after Endoscopic Balloon Dilatation following a Minor Traffic Accident in a Patient with Crohn's Disease: A Case Report.

Introduction: Crohn's disease (CD) is complicated by intestinal strictures and fistula formation; however, intestinal perforation is relatively rare. Case Presentation: Following a traffic accident in the evening, a 39-year-old woman experienced abdominal pain that worsened the following morning and was taken to the emergency department. She had a 17-year history of CD and eight endoscopic balloon dilations for descending colonic strictures. She presented with a high fever of 40.0°C, along with tenderness and rebound pain throughout her abdomen, with the most substantial point being in the lower left abdomen. Computed tomography showed thickening of the descending colon wall, increased fat concentration around the wall, and a slight presence of air in the mesentery near the intestinal wall. We diagnosed the patient with generalized peritonitis due to traumatic penetration of the mesentery of the descending colon and performed emergency surgery. Intraoperative observation of the abdominal cavity with a laparoscope revealed purulent ascites but no apparent perforation or edematous mesentery, with white moss and redness in the descending colon. This prompted the decision to perform peritoneal lavage drainage and a transverse colonic double colostomy. The postoperative course was favorable, and the patient was discharged from the hospital on the postoperative day 14. Four months after discharge, colostomy closure was performed. Conclusion: Relatively minor trauma in patients with CD can result in colon injury. An injured bowel is usually accompanied by active lesions due to CD; however, caution is required, as endoscopic balloon dilatation without accompaniment may be a background factor.

Squamous cell carcinoma of the anus successfully treated with multidisciplinary therapy for metachronous metastatic and local recurrences after DCF chemotherapy: a case report.

BACKGROUND: Docetaxel, cisplatin, and 5-fluorouracil (DCF) chemotherapy is reportedly an effective treatment strategy for squamous cell carcinoma of the anus (SCCA). However, studies regarding its use in Japanese patients remain scarce. CASE PRESENTATION: Here, we present the case of an 82-year-old woman with SCCA, cStage IIIB. Chemoradiotherapy was initiated after colostomy of the anorectal mass; however, para-aortic lymph node recurrence was observed 3 months after treatment completion. Five courses of DCF chemotherapy were subsequently administered, resulting in a complete response (CR). Two years and 1 month later, the aortic lymph node was enlarged again, and the patient achieved CR again after radiotherapy. Nine months later, local recurrence was detected in the anal canal, and laparoscopic perineal rectal amputation was performed. The patient remains progression-free 5 years and 10 months after the initial treatment and 1 year and 7 months after the final treatment. CONCLUSIONS: Our findings suggest that complementary treatment after DCF chemotherapy may be efficacious in Japanese patients with SCCA and help achieve CR. Despite occasional local recurrences, this approach may help achieve long-term progression-free survival.

Two-Team Transanal Total Mesorectal Excision and En Bloc Resection of the Lateral Pelvic Lymph Nodes, Main Iliac Vessels, and Pelvic Plexus for Locally Advanced Rectal Cancer With Lateral Lymph Node Metastasis.

BACKGROUND: Here, we describe the precise surgical technique for a novel procedure involving 2-team transanal total mesorectal excision with en bloc lateral pelvic lymph node (LPLN) dissection combined with resection of the involved main internal iliac vessels and pelvic plexus. METHODS: From September 2020 to May 2023, 4 patients underwent the procedure at our hospital. RESULTS: The operation time and blood loss were 272 to 412 minutes and 10 to 124 mL, respectively. No patients required conversion to open surgery or exhibited Clavien-Dindo grade III or worse postoperative complications, although 2 developed grade II urinary dysfunction. All surgical margins were negative. CONCLUSIONS: Our novel 2-team method can facilitate safe and satisfactory surgery, even for highly advanced rectal cancer. The transanal approach offers excellent visibility and operability, even during LPLN and adjacent structure dissection. Furthermore, initial dissection of the distal branches of the iliac vessels prevents excessive lymphatic tissue congestion, facilitating easier, and clearer dissection.

Effectiveness of Combination Chemotherapy With Docetaxel, Nedaplatin, and 5-Fluorouracil for Advanced and Recurrent Esophageal Cancer.

BACKGROUND/AIM: Chemotherapy and immunotherapy have been recently developed as potentially useful first-line treatments for unresectable, advanced, or recurrent esophageal cancer. We performed a retrospective study of the therapeutic effectiveness of triplet chemotherapy with docetaxel, nedaplatin, and 5-fluorouracil therapy for advanced, recurrent, and unresectable advanced esophageal cancer at our hospital and compared the regimen's results with those of current and possible future treatment options. PATIENTS AND METHODS: The study cohort comprised 101 patients who received docetaxel, nedaplatin, and 5-fluorouracil for advanced or recurrent esophageal cancer at Gunma University from May 2008 to December 2017. We retrospectively evaluated the results of this combination chemotherapy and postulated future treatment strategies. RESULTS: The overall response and disease control rates, the latter including stable disease, for docetaxel, nedaplatin, and 5-fluorouracil were 33.6% and 61.4%, respectively. The median overall survival and progression-free survival were 12.26 months and 5.1 months, respectively. In patients with recurrence, the median overall and progression-free survivals were 14.97 months (449 days) and 5.1 months (152 days), respectively. No study patients developed acute kidney injury and there were no treatment-related deaths. However, leukopenia and neutropenia were frequent hematologic toxicities. CONCLUSION: Treatment with docetaxel, nedaplatin, and 5-fluorouracil for advanced or recurrent esophageal cancer is particularly useful for recurrent cases and has the advantage of not causing severe renal dysfunction.

Prognostic value of a modified­immune scoring system in patients with pathological T4 colorectal cancer.

Tumor-infiltrating immune cells, such as lymphocytes and macrophages, have been associated with tumor aggressiveness, prognosis and treatment response in colorectal cancer (CRC). An immune scoring system, Immunoscore (IS), based on tumor-infiltrating T cells in stage I-III CRC, was used to predict prognosis. An alternative immune scoring signature of immune activation (SIA) reflects the balance between anti- and pro-tumoral immune components. The present study aimed to evaluate the prognostic value of modified IS (mIS) and modified SIA (mSIA) in locally advanced pathological T4 (pT4) CRC, including stage IV CRC. Immunohistochemical staining for immune cell markers, such as CD3 (pan-T cell marker), CD8 (anti-tumoral cytotoxic T cell marker) and CD163 (tumor-supportive macrophage marker), in specimens from patients with radically resected pT4 CRC at stages II-IV was performed. mIS levels in the T4 CRC cohort were not associated with prognosis. However, low mSIA levels were associated with low survival. Furthermore, low mSIA was an independent predictor of recurrence in patients with radically resected pT4 CRC. In patients with CRC who did not receive postoperative adjuvant chemotherapy, low mSIA was a major poor prognostic factor; however, this was not observed in patients receiving adjuvant chemotherapy. Evaluation of the tumor-infiltrating immune cell population could serve as a valuable marker of recurrence and poor prognosis in patients with locally advanced CRC. mSIA assessment after radical CRC resection may be promising for identifying high-risk patients with pT4 CRC who require aggressive adjuvant chemotherapy.

Adjuvant Chemotherapy With UFT/LV Versus UFT/LV Plus PSK in Stage II/III Colorectal Cancer.

BACKGROUND/AIM: Uracil-tegafur+leucovorin (UFT/LV), an oral adjuvant therapy for stage II/III colorectal cancer, is non-inferior to standard weekly fluorouracil and folinate. Although polysaccharide K (PSK) has been evaluated as a postoperative adjuvant colorectal cancer drug, its efficacy remains unclear. This randomized phase II trial compared UFT/LV+PSK with UFT/LV as adjuvant chemotherapy. PATIENTS AND METHODS: Between April 2011 and August 2016, 186 patients who underwent radical resection randomly received 6 months of UFT/LV (Group A: 300 mg/m2/day UFT and 75 mg/day LV, every 35 days for five cycles), 6 months of UFT/LV+PSK (Group B: standard UFT/LV regimen and daily administration of 3 g/day of PSK), or 12 months of UFT/LV+PSK (Group C). The primary endpoint was the 3-year disease-free survival. RESULTS: Groups A, B, and C consisted of 37, 75, and 74 patients, of which treatment was completed by 33 (89.2%), 63 (84.9%), and 53 (70.4%) patients, respectively (p=0.0279). Adverse event incidence for all grades were 59.5%, 52.1%, and 59.2%, and for grade ≥3 were 13.5%, 9.6%, and 9.9%, respectively. The 3-year disease-free survival rates were 72.5%, 82.2%, and 74.2%, respectively, with no significant differences. The preoperative lymphocyte ratio did not significantly differ between groups. CONCLUSION: UFT/LV+PSK is comparable to UFT/LV therapy in terms of prognostic efficacy and reduced adverse effects. Thus, UFT/LV+PSK is a useful adjuvant chemotherapy option for patients with high-risk stage II/III colorectal cancer.

Retrograde drainage for duodenal stump leakage using ileal decompression tube guided by double-balloon endoscopy: a novel case report.

BACKGROUND: Duodenal stump leakage is a serious post-gastrectomy complication, and there have been no reports on endoscopic drainage. CASE PRESENTATION: We report a case of duodenal stump leakage after laparoscopic gastrectomy with Roux-en-Y reconstruction in a 68-year-old man. First-line conservative management was ineffective. Reoperation was performed because of severe abdominal pain and increased ascites. After reoperation, duodenal stump leakage recurred with bleeding from the anterior superior pancreaticoduodenal artery. Coil embolization and pigtail catheter insertion were performed. Furthermore, we retrogradely inserted an ileal tube for tube decompression near the duodenal stump using double-balloon endoscopy for effective drainage. After tube insertion, duodenal stump leakage decreased; on the 47th primary postoperative day, the patient was discharged. The primary postoperative course was uneventful after 1 year and 9 months of follow-up. CONCLUSIONS: This is the first successful case of duodenal stump leakage treated with retrograde decompression tube insertion near the duodenal stump using double-balloon endoscopy.

Efficacy of thoracic endovascular aortic repair for aorto-esophageal fistula due to esophageal cancer: a systematic review and meta-analysis.

Aorto-esophageal fistula (AEF) due to esophageal cancer (EC) is a life-threatening condition characterized by sudden hemorrhage, which often causes sudden death. To evaluate the efficacy and safety of thoracic endovascular aortic repair (TEVAR) for AEF due to EC, we performed a systematic review and meta-analysis. We searched the MEDLINE (PubMed) databases, the Cochrane Library databases, Ichushi-Web (the databases of the Japan Medical Abstract Society), and CiNii (Academic information search service of the National Institute of Information from Japan) from January 2000 to November 2023 for articles about TEVAR for an emergent aortic hemorrhage (salvage TEVAR [S-TEVAR]), and the prophylactic procedure (P-TEVAR). Six studies (140 cases) were eligible for meta-analysis. The 90-day mortality of S-TEVAR and P-TEVAR was 40% (95% CI 23-60, I2 = 36%) and 8% (95% CI 3-17, I2 = 0%), respectively. Post-S-TEVAR hemorrhagic and infectious complications were 17% (95% CI 3-57, I2 = 71%) and 20% (95% CI 5-57, I2 = 66%), respectively. Post-P-TEVAR hemorrhagic and infectious complications were 2% (95% CI 0-10, I2 = 0%) and 3% (95% CI 1-12, I2 = 0%), respectively. TEVAR for AEF due to EC may be a useful therapeutic option to manage or prevent hemorrhagic oncological emergencies.

A Novel Method for Thoracoscopic Overlap Esophagogastric Reconstruction With Pleural Closure following Minimally Invasive Ivor-Lewis Esophagectomy for Esophagogastric Junction Cancer.

BACKGROUND: Intrathoracic esophagogastric anastomosis following minimally invasive Ivor-Lewis esophagectomy is a technically demanding surgical technique that can result in serious intrathoracic infections when anastomotic leakage occurs. Herein, we report a novel side-overlap esophagogastric anastomosis with pleural closure for esophagogastric junction cancer. METHODS: The 3 key points of our novel technique were the following: (1) overlap esophagogastric anastomosis and closure of the entry hole were all performed using a linear stapler; (2) the pleura was closed to separate the anastomotic site from the thoracic cavity; and (3) the mediastinal drain was inserted transhiatally from the abdominal cavity. RESULTS: This modified anastomosis procedure was performed on 8 consecutive patients at our institution. The median overall/thoracoscopic operating time and estimated blood loss were 652.5/241.5 min and 89 mL, respectively. No mortality or serious postoperative complications occurred, and the median postoperative hospital stay was 22 days (range, 17 to 37 d). CONCLUSION: This novel thoracoscopic overlap esophagogastric reconstruction procedure with pleural closure is safe and feasible.

Usefulness of the preoperative inflammation-based prognostic score and the ratio of visceral fat area to psoas muscle area on predicting survival for surgically resected adenocarcinoma of the esophagogastric junction.

BACKGROUND: Sarcopenic obesity is associated with gastrointestinal cancer prognosis through systemic inflammation. However, in patients with adenocarcinoma of the esophagogastric junction (AEG), the relationship between the inflammation-based prognostic score (IBPS), muscle loss, visceral fat mass, and prognosis has not been sufficiently evaluated. We investigated the prognostic value of the preoperative IBPS and the visceral fat area ratio to the psoas muscle area (V/P ratio) in patients with AEG undergoing surgery. METHODS: We retrospectively analyzed 92 patients with AEG who underwent surgery. The prognostic value of the preoperative neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio, systemic inflammation response index, C-reactive protein-to-albumin ratio, prognostic nutritional index, modified Glasgow Prognostic Score, and V/P ratio at the third lumbar vertebra was investigated using univariate and multivariate survival analyses. RESULTS: Multivariate analysis revealed that a high pathological stage (p = 0.0065), high PLR (p = 0.0421), and low V/P ratio (p = 0.0053) were independent prognostic factors for poor overall survival (OS). When restricted to patients with body mass index (BMI) ≥ 25 kg/m2, a high V/P ratio was a poor prognostic factor (p = 0.0463) for OS. Conversely, when restricted to patients with BMI < 25 kg/m2, a low V/P ratio was a poor prognostic factor (p = 0.0021) for OS. CONCLUSIONS: Both PLR and V/P ratios may be useful prognostic biomarkers in surgical cases of AEG. V/P ratio and BMI may provide an accurate understanding of the muscle and fat mass's precise nature and may help predict AEG prognosis.

Importance of Progression-free Survival in Second-line Chemotherapy in Patients With Advanced or Recurrent Gastric Cancer.

BACKGROUND/AIM: Impact of second-line chemotherapy in unresectable advanced/recurrent gastric/esophagogastric junction cancer (AGC) remains unclear. This retrospective analysis aimed to identify factors affecting prognosis in chemotherapy for patients with AGC, including the importance of progression-free survival in second-line chemotherapy (PFS-2). PATIENTS AND METHODS: Data from a total of 109 patients with AGC that received second-line treatment were analyzed with the aim of clarifying prognostic factors. Furthermore, the correlation between PFS-2 and clinical characteristics and the association between PFS-2 and inflammation-based and/or nutritional markers were investigated. RESULTS: Multivariate analysis identified the following prognostic factors: ECOG PS ≥1, presence of peritoneal dissemination, metastasis in two or more organs, and taxane use on second-line chemotherapy. Short PFS-2 was strongly associated with prognosis in the univariate analysis [hazard ratio (HR)=3.107, 95% confidence interval (CI)=1.969-4.904, p<0.001]. The duration of PFS-2 was significantly correlated with ECOG PS (p=0.019), liver metastasis rates (p=0.035) and taxane use on second-line chemotherapy (p=0.001). In addition, weight loss rate during first-line treatment (p=0.042), white blood cell count (p=0.008), C-reactive protein (p=0.032), c-reactive protein to albumin ratio (p=0.039), prognostic index (p=0.028), and modified Glasgow prognostic score (p=0.027) were significantly associated with the duration of PFS-2. CONCLUSION: The duration of PFS-2 significantly correlated with ECOG PS, liver metastasis, and taxane use on second-line treatment, and strongly affected OS. It was suggested that the presence of malnutrition and inflammation at the start of second-line therapy had a negative impact on PFS-2 and OS.

HLA Class I Expression Is Associated with DNA Damage and Immune Cell Infiltration into Dysplastic and Neoplastic Lesions in Ulcerative Colitis.

Human leukocyte antigen class I (HLA-I) is considered a genetic pathogen for ulcerative colitis (UC). This study aimed to investigate the significance of DNA damage and HLA-I expression in infiltrating immune cells and immune checkpoint protein PD-L1 expression in dysplasia/colitic cancer (CC) and sporadic colorectal cancer (SCRC). We performed immunohistochemical staining for HLA-I, PD-L1, γH2AX (DNA damage marker), and immune cell markers such as CD8, FOXP3, CD68, and CD163 (in surgically resected specimens from 17 SCRC patients with 12 adjacent normal mucosa (NM) and 9 UC patients with 18 dysplasia/CC tumors. The ratio of membrane HLA-I-positive epithelial cells in UC and dysplasia/CC tissues was significantly higher than that in NM and SCRC. High HLA-I expression in dysplasia/CC was associated with high positivity of γH2AX and PD-L1 expression compared to SCRC. The infiltration of CD8-positive T cells and CD68-positive macrophages in HLA-I-high dysplasia/CC was significantly higher than in UC and SCRC. Dysplasia/CC specimens with DNA damage exhibited high levels of HLA-I-positive epithelial cells with high CD8- and CD68-positive immune cell infiltration compared to UC and SCRC specimens. Targeting DNA damage in UC may regulate immune cell infiltration, immune checkpoint proteins, and carcinogenesis by modulating DNA damage-induced HLA-I antigen presentation.

Surgical Techniques and Stoma-related Complications Associated With Emergency Stoma Creation.

BACKGROUND/AIM: Determination of risk factors for stoma-related complications associated with emergency stoma creation may impact on reducing complications and improving the quality of life of ostomy patients; however, there are only few reports on stoma-related complications associated with emergency stoma creation. Our study aimed to identify risk factors associated with stoma-related complications after emergency surgery, and evaluate surgical techniques for good stoma creation in the emergency setting. PATIENTS AND METHODS: A retrospective analysis of patient and surgical characteristics was performed in 104 consecutive patients who underwent ileostomy or colostomy as emergency surgery between January 2020 and December 2022 at the Gunma University Hospital. RESULTS: Preoperative stoma site marking was performed in 70 (67.3%) patients. Colostomies and ileostomies were performed in 78 (75.0%) and 26 (25.0%) patients, respectively. The skin bridge technique was used in 13 (12.5%) patients. Stoma-related complications were diagnosed in 62 (59.6 %) patients, with peristomal skin disorders (47.1%) as the most common complication, followed by mucocutaneous separation (31.7%), and stoma retraction (19.2%). In the multivariate analysis, body mass index (BMI) [odds ratio (OR)=5.570, 95% confidence interval (CI)=1.233-25.167, p=0.026], skin bridge technique (OR=0.144, 95% CI=0.031-0.670, p=0.014), and stoma height (OR=0.134, 95% CI=0.038-0.469, p=0.002) were independent risk factors for stoma-related complications after emergency stoma creation. CONCLUSION: In emergency stoma creation, higher BMI and lower stoma height are associated with stoma-related complications. Using the skin bridge technique could reduce the risk of stoma-related complications after emergency stoma creation.

Significance of Lipopolysaccharides in Gastric Cancer and Their Potential as a Biomarker for Nivolumab Sensitivity.

Lipopolysaccharides are a type of polysaccharide mainly present in the bacterial outer membrane of Gram-negative bacteria. Recent studies have revealed that lipopolysaccharides contribute to the immune response of the host by functioning as a cancer antigen. We retrospectively recruited 198 patients with gastric cancer who underwent surgery. The presence of lipopolysaccharides was determined using immunohistochemical staining, with the intensity score indicating positivity. The relationship between lipopolysaccharides and CD8, PD-L1, TGFBI (a representative downstream gene of TGF-ß signaling), wnt3a, and E-cadherin (epithelial-mesenchymal transition marker) was also investigated. Thereafter, we identified 20 patients with advanced gastric cancer receiving nivolumab and investigated the relationship between lipopolysaccharides and nivolumab sensitivity. After staining for lipopolysaccharides in the nucleus of cancer cells, 150 negative (75.8%) and 48 positive cases (24.2%) were found. The lipopolysaccharide-positive group showed increased cancer stromal TGFBI expression (p < 0.0001) and PD-L1 expression in cancer cells (p = 0.0029). Lipopolysaccharide positivity was significantly correlated with increased wnt3a signaling (p = 0.0028) and decreased E-cadherin expression (p = 0.0055); however, no significant correlation was found between lipopolysaccharide expression and overall survival rate (p = 0.71). In contrast, high TGFBI expression in the presence of LPS was associated with a worse prognosis than that in the absence of LPS (p = 0.049). Among cases receiving nivolumab, the lipopolysaccharide-negative and -positive groups had disease control rates of 66.7% and 11.8%, respectively (p = 0.088). Lipopolysaccharide positivity was associated with wnt3a, TGF-ß signaling, and epithelial-mesenchymal transition and was considered to tend to promote therapeutic resistance to nivolumab.

Infiltration of Gastric Cancer Stroma by Tumor-Infiltrating Lymphocytes Correlates with Mechanistic Target of Rapamycin Signaling.

INTRODUCTION: We investigated whether the infiltration of tumor-infiltrating lymphocytes (TILs) in gastric cancer (GC), as evaluated by hematoxylin and eosin (H&E) staining, could be a prognostic marker. We also explored on the relationship between TILs and mechanistic target of rapamycin (mTOR) and how it regulates immune effector responses in GC. METHODS: A total of 183 patients with available data on TIL were included. TIL infiltration was evaluated using H&E staining. We also conducted immunohistochemistry to determine mTOR expression. RESULTS: Positive TIL infiltration was defined as TILs ≥20%. There were 72 (39.3%) and 111 (60.7%) positive and negative cases, respectively. TILs positivity significantly correlated with both absence of lymph node metastasis (p = 0.037) and negative p-mTOR expression (p = 0.040). TIL infiltration correlated with a significantly better overall (p = 0.046) and disease-free (p = 0.020) survival. CONCLUSION: mTOR possibly suppresses TIL infiltration in GC. H&E staining is an effective tool for evaluating the immune status of GC patients. H&E staining may be used in clinical practice to monitor treatment response in GC.

Two-team Total Mesorectal Excision and Lateral Pelvic Lymph Node Dissection Using Transanal Approach for Rectal Cancer: A Retrospective Study.

BACKGROUND/AIM: Lateral lymph node dissection is a locally advanced rectal cancer treatment option. Despite its complexities, such as prolonged operative time and increased blood loss, a transanal approach with an abdominal approach may help mitigate these drawbacks. PATIENTS AND METHODS: Between July 2013 and June 2022, 40 patients underwent radical laparoscopic surgery with lateral lymph node dissection for rectal cancer. Among them, 29 and 11 patients underwent total mesorectal excision and lateral lymph node dissection without transanal approach (conventional surgery) and with transanal approach (two-team surgery), respectively. The clinical findings, surgical outcomes, pathology results, and prognoses of conventional and two-team surgeries were retrospectively compared. RESULTS: Compared to conventional surgery, two-team surgery involves increased organ and nerve resections, shorter operation time (286 vs. 548 min, p<0.001), and less blood loss (20 vs. 158 ml, p<0.001). Although postoperative complications were similar between groups, the two-team surgery group had a shorter hospital stay (p=0.006). Pathologically, all patients who underwent two-team surgery had a distal resection margin of at least 20 mm, and no recurrence was observed. With conventional surgery, 63.6% of patients had a 10-19 mm margin, and 36.4% had a margin of ≥20 mm, except for abdominoperineal resection. CONCLUSION: Total mesorectal excision and lateral lymph node dissection with the transanal approach as a two-team surgery are safe and feasible. Two-team surgery resulted in better outcomes than conventional surgery regarding operative time, blood loss, shorter postoperative hospital stay, and adequate distal resection margin.

Sigmoid colon schwannoma difficult to distinguish from peritoneal dissemination 13 years after pancreatic neuroendocrine tumor surgery.

BACKGROUND: Schwannoma, which clinicians sometimes struggle to diagnose, is a tumor arising from Schwann cells of peripheral nerves, often in the soft tissues and rarely in the gastrointestinal tract. Pancreatic neuroendocrine tumor (PNET) is rare among pancreatic tumors, and recurrence can occur long after resection. Here, we were presented with a case where a sigmoid colon schwannoma was difficult to distinguish from a postoperative recurrence of PNET and was diagnosed after laparoscopic resection. CASE PRESENTATION: A 51-year-old man was diagnosed with PNET (NET G2) after a distal pancreatectomy (DP) 13 years ago. The patient underwent hepatectomy due to liver metastasis 12 years after initial radical surgery. The follow-up magnetic resonance imaging (MRI) after hepatectomy showed pelvic nodules, and laparoscopic surgery was performed for both diagnosis and treatment because peritoneal dissemination of PNET could not be ruled out. Since the tumor was in the sigmoid colon, a partial colon resection was performed. The histopathological diagnosis was a schwannoma, and the patient was discharged on the seventh postoperative day. CONCLUSIONS: We experienced a case of sigmoid colon schwannoma that was difficult to differentiate from peritoneal dissemination of PNET and was later diagnosed after laparoscopic resection. In addition, this case involved a long-term postoperative recurrence of PNET that was amenable to radical resection, further establishing the importance of long-term imaging follow-up.

Retroperitoneal urothelial carcinoma arising after bladder diverticulectomy: a case report.

BACKGROUND: Urothelial carcinoma arises from the inner urothelial membrane of the renal pelvis, ureter, and bladder and often causes macrohematuria. Here, we report a rare case in which the patient developed non-symptomatic urothelial carcinoma anatomically outside the bladder wall 17 years after bladder diverticulectomy. CASE PRESENTATION: An 82-year-old male patient previously underwent gastrectomy for stomach cancer and partial hepatectomy for intrahepatic cholangiocarcinoma. Follow-up computed tomography revealed a tumor in the retroperitoneal space, where a bladder diverticulum was removed 17 years earlier. Multiparametric magnetic resonance imaging suggested that the tumor was malignant with rectal invasion. Subsequent computed tomography-guided percutaneous biopsy revealed that the tumor was urothelial carcinoma. The patient underwent two courses of neoadjuvant chemotherapy followed by pelvic exenteration with pelvic lymph node dissection. He is currently receiving adjuvant therapy with an immune checkpoint inhibitor and has had no recurrence for 3 months. CONCLUSIONS: Multiparametric magnetic resonance imaging is a helpful tool for predicting both tumor malignancy and invasion before a pathologically confirmed diagnosis. Although this case is rare, urologists should be aware of the occurrence of urothelial carcinoma after bladder diverticulectomy in cases of incomplete resection of the diverticulum.

Albumin-derived Neutrophil-to-Lymphocyte Ratio Score as a Marker of Nivolumab Treatment Sensitivity in Gastric Cancer: A Multicenter Study.

BACKGROUND/AIM: Establishment of powerful and easy-to-evaluate biomarkers that can predict immune checkpoint inhibitor sensitivity in patients with gastric cancer (GC) would be highly useful. The albumin-derived neutrophil-to-lymphocyte ratio (Alb-dNLR) score reportedly is an excellent measure of both immunity and nutritional status. However, the association between nivolumab treatment sensitivity and Alb-dNLR in GC has also not been adequately investigated. This multicenter retrospective study was designed to evaluate the association of Alb-dNLR with therapeutic sensitivity of nivolumab in GC patients. PATIENTS AND METHODS: This was a retrospective multicenter study with patients from five sites. The data from 58 patients who received nivolumab for postoperative recurrent or unresectable advanced GC between October 2017 and December 2018 were analyzed. Blood tests had been performed before nivolumab administration. We analyzed the correlation between the Alb-dNLR score and clinicopathological factors, including best overall response. RESULTS: Of the 58 patients, 21 (36.2%) comprised the disease control (DC) group and 37 (63.8%) comprised the progressive disease (PD) group. The nivolumab treatment responses were subjected to receiver operating characteristic analysis. The cutoff value was set to 2.90 g/dl for Alb and to 3.55 for dNLR. All eight patients in the high Alb-dNLR group had PD (p=0.0049). The low Alb-dNLR group had significantly better overall survival (p=0.0023) and progression-free survival rates (p<0.0001). CONCLUSION: The Alb-dNLR score was a very simple and sensitive predictor of nivolumab therapeutic sensitivity and has very good biomarker properties.