Impact of Circular Stapler Size on the Risk of Anastomotic Complications in Patients With Left-sided Colorectal Cancer: A Propensity Score-matched Study.

Background/Aim: The present study examined the impact of circular stapler size on anastomotic complications, including leakage and stricture in patients undergoing double-stapling technique (DST) anastomosis for left-sided colon or rectal cancer. Patients and Methods: A total of 403 patients were enrolled in this study, with circular stapler sizes  of 25, 28, and 29 mm. Results: A small circular stapler (25 mm) was used in 170 cases (42.2%), and a medium-sized circular stapler (28/29 mm) was used in 233 cases (57.8%). After propensity score matching, there was no marked difference in the incidence of anastomotic leakage/stricture between the groups (13.9% vs. 10.9%, 3.0% vs. 1.0%, respectively). Conclusion: The size of the circular stapler was not associated with the incidence of anastomotic leakage or stricture in this cohort.

The Efficacy of Chemical Bowel Preparation Against Incisional Surgical Site Infection in Colorectal Cancer Surgery: A Propensity Score Matching Study.

BACKGROUND/AIM: In colorectal cancer surgery, the risk of surgical site infection (SSI) is relatively high. The development of SSI is related to longer and costlier hospitalization and reduced quality of life; therefore, perioperative prevention of SSI is important. Chemical bowel preparation (CBP) combined with mechanical bowel preparation (MBP) may be more effective in preventing surgical site infection (SSI) compared to MBP alone. Since May 2021, we have been administering oral kanamycin and metronidazole as CBP, in addition to MBP, as a preoperative treatment for colorectal cancer surgery on the day before surgery. In this study, we investigated the clinical value of CBP in addition to MBP in colorectal cancer surgery using propensity score matching (PSM). PATIENTS AND METHODS: From January 2017 to December 2021, 136 consecutive patients underwent radical surgery for sigmoid colon and rectal cancer at the Osaka Metropolitan University Hospital. Patients were divided into two groups: CBP and N-CBP. In the N-CBP group, we performed only preoperative MBP, whereas in the CBP group, we performed preoperative CBP in addition to MBP. We retrospectively analyzed this relationship with PSM. RESULTS: Overall, 46 patients underwent preoperative CBP and MBP, 90 patients underwent preoperative MBP only. PSM was performed between the CBP and N-CBP groups based on the following ten factors: age, sex, diabetes mellitus, preoperative therapy, Glasgow Prognostic Score (GPS), operative time, blood loss, stoma, and pathological stage. After PSM, univariate and multivariate analyses of the relationship between SSI and clinicopathological factors were performed. Univariate analysis showed that age and CBP were correlated with the rate of SSI (p=0.039 and p=0.017, respectively), whereas sex was relatively correlated with the rate of SSI (p=0.066). The multivariate analysis of significant factors identified age of 75 or more and non-CBP as an independent risk factor for incisional SSI (HR=9.5; p=0.049 and HR=5.4×e-8; p=0.020). CONCLUSION: Preoperative CBP in addition to MBP was effective in preventing incisional SSI during colorectal cancer surgery.

An 8-mm port site hernia after robotic-assisted ileocecal resection: a case report.

BACKGROUND: Robotic-assisted surgery is steadily becoming more prominent. The majority of reports regarding port site hernias (PSHs) have involved laparoscopic procedures. Currently, it is common to suture the fascia at port sites that are 10 mm or larger; however, the closure of 5-mm port sites is not considered mandatory. The da Vinci® surgical system (Intuitive Surgical Inc., Sunnyvale, CA, USA) utilizes a distinctive 8-mm port. We report a case of an early-onset PSH at an 8-mm port site after robotic-assisted ileocecal resection. CASE PRESENTATION: A 74-year-old male patient with a body mass index of 19.7 kg/m2 was diagnosed with cecal cancer and underwent robotic-assisted ileocecal resection. A 3-cm midline incision was made at the umbilicus for insufflation. Under laparoscopic visualization, three ports (12 mm, 8 mm, and 8 mm) were inserted in the lower abdomen. An 8-mm port was inserted in the left subcostal region, and a 5-mm port was inserted in the left lateral abdomen. The procedure was performed without significant intraoperative complications. The fascia was closed only at the umbilicus and 12-mm port site; the fascia at the 8-mm port sites was not closed. The patient was initially discharged without complications; however, on postoperative day 11, the patient was urgently hospitalized again because of PSH incarceration. After manual reduction, the fascia was sutured closed under local anesthesia. The hernial defect was small and barely allowed the insertion of a little finger. There was no evidence of compression or significant damage to the fascia. On postoperative day 27, the patient was discharged after experiencing good recovery. CONCLUSIONS: Robotic-assisted colectomy could contribute to the risk of PSHs because of its surgical characteristics. Although routine closure of the fascia at 8-mm port sites is not mandatory, it may be beneficial in certain cases.

Prognostic significance of connective tissue growth factor expression in stromal cells in patients with diffuse­type gastric cancer.

Connective tissue growth factor (CTGF) is a target gene of the Hippo signaling pathway. Its differential role in the histological types of gastric cancer (GC) remains unknown; therefore, the present study aimed to confirm the clinical significance of CTGF expression in cancer and stromal cells in patients with GC depending on the histological type. The present study enrolled 589 patients with GC. Immunohistochemistry was used to analyze CTGF expression in cancer and stromal cells. CTGF mRNA expression data and the corresponding clinical information of GC samples were collected from The Cancer Genome Atlas (TCGA) database. Subsequently, the associations between CTGF expression and several clinicopathological factors were investigated. In the present study, CTGF expression was mainly observed in the cytoplasm of cancer and stromal cells. CTGF expression in stromal cells was significantly associated with CTGF expression in cancer cells (P<0.001). CTGF positivity in stromal cells was also significantly associated with intestinal type, non-scirrhous type, tumor depth (T1-2), lymph node metastasis (negative), lymphatic invasion (negative) and tumor size (<5 cm). Low CTGF expression in stromal cells was independently associated with worse overall survival (OS). Furthermore, the OS of patients with low CTGF expression in stromal cells, especially in patients with diffuse-type GC, was significantly worse than patients with high CTGF expression (P=0.022). This trend was similar to that revealed by TCGA data analysis. In conclusion, low CTGF expression was associated with a significantly worse OS in patients with diffuse-type GC. These data indicated that CTGF, and its control by the Hippo pathway, may be considered potential treatment targets in diffuse-type GC.

Effects of an artificial pancreas on postoperative inflammation in patients with esophageal cancer.

PURPOSES: Subtotal esophagectomy for esophageal cancer (EC) is associated with high morbidity rates. Tight glycemic control using an artificial pancreas (AP) is one of the promising strategies to reduce postoperative inflammation and morbidities. However, the effects of tight glycemic control using AP in patients with EC are yet to be fully elucidated. METHOD: This study reviewed 96 patients with EC who underwent subtotal esophagectomy. The postoperative inflammation parameters and morbidity rates were compared between patients who used the AP (n = 27) or not (control group, n = 69). AP is a closed-loop system that comprises a continuous glucose monitor and an insulin pump. RESULTS: The numbers of white blood cells (WBC) and Neutrophils (Neut) were noted to be lower in the AP group than in the control group, but with no significant difference. The ratio in which the number of WBC, Neut, and CRP on each postoperative day (POD) was divided by those tested preoperatively was used to standardize the results. The ratio of WBC and Neut on 1POD was significantly lower in the AP group than in the control group. The rate of surgical site infection was lower in the AP group than in the control group. CONCLUSION: AP significantly decreased WBC and Neut on 1POD; this suggests the beneficial effects of AP in alleviating postoperative inflammation.

An Improvement of Exertional Dyspnea by the Reintroduction of Anti-EGFR Antibody in Patients with Metastatic Rectal Cancer Who Developed Cancerous Lymphangiopathy: A Case Report.

Introduction: Reexposure to anti-EGFR antibodies, such as a reintroduction or rechallenge with anti-EGFR antibodies, has attracted much attention in the field of metastatic colorectal cancer. A reintroduction of anti-EGFR antibodies often shows good therapeutic outcomes, as most patients eligible for such reintroduction discontinued treatment due to adverse events despite a good treatment response during front-line treatment. We herein report a case demonstrating an improvement in exertional dyspnea after the reintroduction of anti-EGFR antibody in a patient with metastatic rectal cancer who developed cancerous lymphangiopathy. Case Presentation: A 68-year-old man who had undergone curative surgery for stage IIIB rectal cancer was diagnosed with multiple lung metastases. During the late-line treatment, respiratory failure developed because of multiple lung metastases and cancerous lymphangiopathy. Two months after the initiation of irinotecan + cetuximab, which had been discontinued due to acneiform eruptions despite a good treatment response as a first-line treatment, his dyspnea and performance status dramatically improved. Conclusion: This case indicates that the reintroduction of anti-EGFR antibody to patients who have discontinued anti-EGFR antibody due to skin toxicity despite a good treatment response is a very useful treatment option for metastatic colorectal cancer.

Optimal extent of lymph node dissection for high-risk gastric cancer stratified by a national clinical database risk calculator.

BACKGROUND: For patients with gastric cancer, a well-balanced treatment that considers both oncological aspects and surgical risk is demanded. This study aimed to explore the optimal extent of lymph node dissection (LND) for patients with gastric cancer according to surgical risk, stratified by the risk calculator system produced by the Japan National Clinical Database (NCD). PATIENTS AND METHODS: We retrospectively evaluated 187 patients who underwent radical gastrectomy for gastric cancer. Using the median predicted anastomotic leak rate obtained by the NCD risk calculator as the cutoff value, we classified 97 and 90 patients as having high and low risks, respectively. RESULTS: In low-risk patients, although limited LND reduced the postoperative intraabdominal infectious complications (IAIC), multivariate analysis revealed standard LND as an independent prognostic factor that improved Relapse-free survival (RFS). In high-risk patients, the rates of postoperative IAIC and RFS were similar between standard and limited LND. Pancreatic fistula was not observed in the limited dissection group. CONCLUSION: Limited LND might be the optimal treatment strategy for patients with gastric cancer with high surgical risk.

The Effect of Bidirectional Barbed Sutures on the Duration of Common Enterotomy Closure in Intracorporeal Anastomosis.

BACKGROUND/AIM: The adoption of intracorporeal anastomosis in minimally invasive surgery for colon cancer has gradually expanded owing to its many advantages. However, intracorporeal anastomosis has the disadvantage of a longer operative time than extracorporeal anastomosis. One reason that intracorporeal anastomosis takes longer to perform is the closure of the common enterotomy. The present study evaluated the effect of bidirectional barbed sutures on the duration of common enterotomy closure in intracorporeal anastomosis for minimally invasive colectomy. MATERIALS AND METHODS: The time required for common enterotomy closure was measured with a simulator using an intestinal model. A two-layer suture with continuous full-thickness suture followed by a continuous serosal-muscular suture was adopted. The time required to close the common enterotomy using two unidirectional barbed sutures and one bidirectional barbed suture was measured five times each. RESULTS: The duration of common enterotomy closure using bidirectional barbed suture was significantly shorter than that using two conventional barbed sutures. CONCLUSION: Bidirectional barbed sutures are useful for closing the common enterotomy in intracorporeal anastomosis for minimally invasive colectomy.

Evaluation of Intraoperative Neural Monitoring During Thoracoscopic Surgery for Esophageal Cancer.

BACKGROUND/AIM: Recurrent laryngeal nerve paralysis (RLNP) induces aspiration pneumonia and reduces the patient's quality of life. To decrease the incidence of RLNP, we performed intraoperative neural monitoring (IONM) during thoracoscopic surgery for esophageal cancer and evaluated its usefulness. PATIENTS AND METHODS: A total of 737 consecutive patients who underwent thoracoscopic surgery for esophageal cancer were enrolled in this study. Between May 1995 and March 2016, thoracoscopic esophagectomies were performed using video-assisted thoracoscopic surgery (VATS) with a small incision, whereas from April to June 2023, we used positive pressure pneumothorax with port placement only [minimum invasive esophagectomy (MIE)]. A total of 110 consecutive patients who underwent thoracoscopic surgery with IONM (IONM group) were retrospectively compared with those who underwent VATS or MIE without IONM (No-IONM group). RESULTS: The incidence of RLNP [Clavien-Dindo (CD) classification of ≥1] on postoperative day (POD) 5 was 13.9% in the IONM group, which was significantly lower than that of the no-IONM group (31.2%, p<0.001). Even when comparing only patients who underwent MIE, the incidence of RLNP on POD5 was 13.9% in the IONM group, which was significantly lower than that in the no-IONM group (26.2%, p=0.035). The incidence of postoperative pneumonia (CD ≥2) was 10.9% in the IONM group, which was significantly lower than that in the no-IONM group (26.1%, p=0.005). Bilateral RLNP did not occur in any of the IONM groups. CONCLUSION: IONM is a useful tool for reducing RLNP incidence and postoperative pneumonia after thoracoscopic surgery for esophageal cancer.

Usefulness of intraoperative ultrasound examination for laparoscopic right-side colon cancer surgery: a propensity score-matched study.

Complete mesocolic excision (CME) with central vascular ligation (CVL) in laparoscopic surgery for right-sided colon cancer (RSCC) requires a precise understanding of the vascular anatomy. The efficacy of intraoperative ultrasound (IUS) in the identification of blood vessels for RSCC surgery was not evaluated. The aim of this study was to compare the intraoperative and short-term outcomes of CME with CVL with or without IUS by laparoscopic surgery for RSCC. We performed IUS on 26 patients of RSCC and compared with a total of 124 patients who underwent the surgery for RSCC at our institution. Propensity score matching (PSM) was performed to reduce the confounding effects to imbalances in the use of IUS. The IUS identified the main feeding artery and the accompanying vein in all 26 cases. After PSM, the amount of intraoperative blood loss in the IUS group was significantly lower than that in the conventional group (5 ml vs. 30 ml, p = 0.035) and no significant difference of the postoperative complications was observed. The IUS reduced the risk of bleeding in the surgery for RSCC. The IUS is a safe and feasible technique that help the surgeons for anatomical understandings under real-time condition in the laparoscopic surgery of RSCC.

[A Case of Advanced Recurrent Rectal Cancer Successfully Treated by Rechallenge Therapy with an Anti-Epidermal Growth Factor Receptor(EGFR)Drug].

The patient was a 75-year-old man who had undergone potentially curative surgery for Stage Ⅲb rectal cancer followed by resection of liver metastases. Two years after the resection of liver metastases, lung and remnant liver metastases were found. He received chemotherapy for unresectable metastatic tumors. Based on the findings of molecular and pathological examinations(RAS: wild type; BRAF: wild type; MSI: negative; HER2: negative), the following chemotherapy regimens were administered: first-line, FOLFIRI plus panitumumab(PANI); second-line, mFOLFOX6; third-line, trifluridine/tipiracil; fourth- line, regorafenib. After fourth-line treatment, he was judged to have disease progression due to the increase in his lung and liver metastases and the elevation of tumor markers. All standard regimens were refractory, but the Eastern Cooperative Oncology Group performance status was zero and a liquid biopsy for RAS still showed wild type. Therefore, rechallenge therapy with anti-epidermal growth factor receptor(EGFR)drugs, cetuximab(CET)and irinotecan(IRI), was administered 13 months after the final course of FOLFIRI plus PANI treatment. After 4 courses of CET plus IRI, the size of the 2 metastatic tumors markedly decreased and his tumor marker levels normalized.

[A Case of Robot-Assisted Abdominoperineal Resection Alongside En Bloc Prostatectomy and Vesico-Urethral Anastomosis for Local Recurrence].

A 66-year-old man presenting with cStage Ⅲc rectal cancer underwent laparoscopic low anterior resection(D3 lymph node dissection and R0 resection)following neoadjuvant chemoradiotherapy(capecitabine, 45 Gy/25 Fr)and received adjuvant chemotherapy(CAPOX). A year after surgery, abdominal contrast-enhanced computed tomography revealed recurrence near the rectal anastomosis with prostate invasion. The patient underwent robot-assisted abdominoperineal resection alongside en bloc prostatectomy and vesico-urethral anastomosis after 12 courses of neoadjuvant chemotherapy(FOLFIRI and panitumumab). He exhibited a good postoperative course and was discharged on the 12th postoperative day. After 7 months of surgery, no recurrence was observe; and urinary incontinence seen immediately after surgery gradually improved.

[A Case of Late Recurrence of Anal Canal Carcinoma after Surgery, Discovered following the Diagnosis of a Subcutaneous Tumor in the Perineal Region].

We present an 82-year-old male patient who underwent laparoscopic abdominal perineal rectal amputation and D3 lymph node dissection, including left inguinal lymph node dissection for anal canal carcinoma. Left inguinal lymph node metastasis was positive, and pT1bN2aM0, pStage Ⅲa was the final pathological diagnosis. He underwent 8 courses of capecitabine plus oxaliplatin therapy as adjuvant chemotherapy. He was examined without recurrence for 5 years postoperatively. However, he awared a perineal subcutaneous tumor and was transferred to our hospital for further examination and treatment 6 years postoperatively. Recurrence after anal canal carcinoma surgery was diagnosed based on a needle biopsy, and perineal subcutaneous tumor resection was performed. This is a rare case of late postoperative recurrence of anal canal carcinoma, which was detected due to a perineal subcutaneous tumor 6 years after surgery for anal canal carcinoma.

[A Case of Sigmoid Colon Cancer with Simultaneous Solitary Adrenal Metastasis Refractory to Preoperative Diagnosis].

A 72-year-old man was referred to our urology department due to a giant adrenal tumor detected by computed tomography( CT). Endocrine screening showed that cortisol, renin, aldosterone, adrenaline, and noradrenaline levels were all normal, and there was no evidence of adrenal hyperfunction. The adrenal tumor was so large that we suspected malignancy. Contrast-enhanced CT of the abdomen was performed for qualitative diagnostic purposes, and showed wall thickening of the sigmoid colon extending for approximately 6 cm. Lower gastrointestinal endoscopy was performed and revealed a full circumferential type 2 tumor in the sigmoid colon. Biopsy results showed intermediate differentiated ductal adenocarcinoma. Tumor markers were as follows: CEA 23.1 ng/mL, CA19-9 962 U/mL. The adrenal tumor was suspected of being malignant due to its size, but imaging examinations did not lead to a diagnosis of primary or metastatic disease. There were no tumors other than those in the sigmoid colon and adrenal glands. Since complete resection was deemed possible, sigmoid colon resection and combined left adrenalectomy were performed for both a diagnosis and treatment. A histopathological examination revealed that the histology of the adrenal tumor resembled that of colorectal cancer, leading to a diagnosis of left adrenal metastasis from sigmoid colon cancer.