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.

Protocol of a pilot randomized clinical trial to evaluate nutritional support and rehabilitation on prevention of skeletal muscle mass loss during neoadjuvant chemotherapy in patients with esophageal cancer.

BACKGROUND: Subtotal esophagectomy with lymph node dissection followed by neoadjuvant chemotherapy (NAC) is the standard treatment for stage II-III esophageal cancer. Esophagectomy is still associated with high morbidity rates, and reducing these rates remains challenging. Among several complications, postoperative pneumonia (PP) is sometimes fatal, which has been reportedly caused by sarcopenia. Thus, nutritional support and rehabilitation may be promising for preventing skeletal muscle mass loss and reduce the incidence of PP. METHODS: This single-center, randomized, open-label, pilot trial will randomize a total of 40 patients with esophageal cancer in a 1:1 ratio either to ISOCAL Clear + rehabilitation arm or only rehabilitation arm. Although all patients will be educated about rehabilitation by a specialized physician and will be asked to undergo the prespecified rehabilitation program, patients treated with ISOCAL Clear + rehabilitation arm will be supplemented by 400 mL of ISOCAL Clear (Nestlé Japan Ltd, Tokyo, Japan) per day during two courses of NAC with docetaxel, cisplatin, and fluorouracil. Body composition will be assessed using Inbody (Inbody Co., Ltd., Tokyo, Japan) just before starting NAC and surgery. The primary endpoint is the change of skeletal muscle index (SMI) during NAC. Secondary endpoints include (i) body weight, total skeletal muscle mass, appendicular skeletal muscle mass, and lean body mass index changes; (ii) the percentage of ISOCAL Clear continuation; (iii) appetite evaluation; (iv) the percentage of targeted calorie achievement; (v) adverse events of NAC; (vi) postoperative complication rates; and (vii) postoperative hospital stay. DISCUSSION: This prospective trial assesses the efficacy of nutritional support in addition to rehabilitation during NAC for patients with esophageal cancer. The results will be utilized in assessing whether the effects of nutritional support by ISOCAL Clear are promising or not and in planning future larger clinical trials.

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.

Involvement of CX3CR1+ cells appearing in the abdominal cavity in the immunosuppressive environment immediately after gastric cancer surgery.

BACKGROUND: Gastric cancer is primarily treated by surgery; however, little is known about the changes in the intraperitoneal immune environment and the prognostic impact of surgery. Surgical stress and cancer-associated inflammation cause immune cells to mobilize into the abdominal cavity via numerous cytokines. One such cytokine, CX3CR1, has various immune-related functions that remain to be fully explained. We characterized the intraperitoneal immune environment by investigating CX3CR1+ cells in intraperitoneal lavage fluid during gastric cancer surgery. METHODS: Lavage fluid samples were obtained from a total of 41 patients who underwent gastrectomy. The relative expression of various genes was analyzed using quantitative real-time PCR. The association of each gene expression with clinicopathological features and surgical outcomes was examined. The fraction of CX3CR1+ cells was analyzed by flow cytometry. Cytokine profiles in lavage fluid samples were investigated using a cytometric beads array. RESULTS: CX3CR1high patients exhibited higher levels of perioperative inflammation in blood tests and more recurrences than CX3CR1low patients. CX3CR1high patients tended to exhibit higher pathological T and N stage than CX3CR1low patients. CX3CR1 was primarily expressed on myeloid-derived suppressor cells and tumor-associated macrophages. In particular, polymorphonuclear myeloid-derived suppressor cells were associated with perioperative inflammation, pathological N, and recurrences. These immunosuppressive cells were associated with a trend toward unfavorable prognosis. Moreover, CX3CR1 expression was correlated with programmed death-1 expression. CONCLUSIONS: Our results suggest that CX3CR1+ cells are associated with an acute inflammatory response, tumor-promotion, and recurrence. CX3CR1 expression could be taken advantage of as a beneficial therapeutic target for improving immunosuppressive state in the future. In addition, analysis of intra-abdominal CX3CR1+ cells could be useful for characterizing the immune environment after gastric cancer surgery.

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.

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.

[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.