Numerous biomarkers that reflect host status have been identified for patients with metastatic colorectal cancer (mCRC). However, there has been a paucity of biomarker studies that comprehensively indicate body composition, nutritional assessment, and systemic inflammation status. The advanced lung cancer inflammation index (ALI), initially introduced as a screening tool for patients with non-small-cell lung cancer in 2013, emerges as a holistic marker encompassing all body composition, nutritional status, and systemic inflammation status. The index is calculated by the simple formula: body mass index × albumin value / neutrophil-to-lymphocyte ratio. Given its accessibility in routine clinical practice, the ALI has exhibited promising clinical utility in prognosticating outcomes for patients with multiple types of cancer. In this review, we focus on the significance of host status and the clinical applicability of the ALI in the treatment and management of patients with malignancies, including mCRC. We also suggest its potential in guiding the formulation of treatment strategies against mCRC and outline future perspectives.

Objectives: The present study reviewed cases of Toxic megacolon (TM) treated in our department, summarized the timing and technique of surgery, and considered key points for surgical management.

Methods: This single-center retrospective study included the medical records of patients clinically diagnosed with TM who underwent surgery between 1985 and 2020. The diagnostic criteria and screening scores for sepsis, such as the systemic inflammatory response syndrome (SIRS) criteria, quick Sequential Organ Failure Assessment (qSOFA) score, and Modified Early Warning Score (MEWS), were validated. The preoperative clinical features and perioperative findings were also investigated.

Results: There were eight male and six female patients. Nine patients (64.3%) satisfied the criteria for toxemia proposed by Narabayashi, and 10 patients (71.4%) fulfilled the SIRS criteria. A positive qSOFA score was confirmed in 1 patient (7.1%). The MEWS was high in 2 patients (14.3%). Intestinal perforation occurred in 2 patients (14.3%), and 1 of them died from disseminated intravascular coagulation. The mortality rate of TM with perforation was 50%. Eleven patients (78.6%) underwent total colectomy with end ileostomy.

Conclusions: TM does not have well-defined diagnostic criteria, in addition to developing sometimes as borderline or fulminant cases, and must be recognized at an early stage, taking various findings into consideration. The criteria proposed by Narabayashi and the SIRS criteria, which met in a high percentage of our cases, are recommended as indicators for determining the toxicity of TM. It is also important to consider surgery in the early stages of TM, even if clinical findings do not meet all the criteria.

Objectives: Laparotomy for lower intestinal perforation is associated with a high incidence of surgical site infections. This study aimed to assess whether incisional negative pressure wound therapy (iNPWT) could reduce the incidence of these infections and wound dehiscence in patients with lower intestinal perforation.

Methods: This single-center prospective study was conducted between September 2019 and July 2022. In the therapy group, wounds were closed with subcuticular sutures, and iNPWT was applied at -120 mmHg for 5 days. A total of 10 days of iNPWT was employed. These patients were compared with a historical control group. The iNPWT group (Group A) comprised 22 patients.The historical control group (Group B) had 65 patients. Table 1 outlines patient characteristics and compares the two study groups.

Results: Patient characteristics were demographically similar. The incidence of surgical site infections was lower in the therapy group than in the control group (9.1% vs. 52.3%, p < 0.001). Wound dehiscence was not observed in the therapy group but was noted in three patients (4.6%) in the control group. In univariate and multivariate analysis, an application of the therapy device was associated with reduced incidence of surgical site infections (p < 0.001 and p = 0.002, respectively).

Conclusions: The application of iNPWT in patients with lower intestinal perforation was associated with reduced surgical site infections.

Objectives: Due to its rarity, there is insufficient evidence for managing ASCC patients with distant metastasis. Thus far, the therapeutic strategy for distant metastasis of ASCC is less standardized and requires a more individualized approach. Therefore, it is crucial to obtain information regarding treatment outcomes and prognostic factors following the development of distant metastasis to identify optimal care strategies for better patient outcomes and predict their prognosis.

Methods: In the multi-institute cohort study conducted in Japan, we retrospectively assessed 58 ASCC patients with synchronous distant metastasis and 28 ASCC patients with metachronous distant metastasis.

Results: When comparing the OS between ASCC patients with synchronous distant metastasis and metachronous distant metastasis, there was no statistically significant difference between the two groups. The OS rate at five years was 37.4% for patients with synchronous distant metastasis and 27.6%; for metachronous distant metastasis. In ASCC patients with synchronous distant metastasis, patients with distant metastasis at multiple sites exhibited extremely worse OS than those at single sites (HR: 4.56, 95% CI: 1.16-18.00, P< 0.0001). In addition, in ASCC patients with metachronous distant metastasis, early recurrence was an independent factor for predicting poor OS in the multivariate analysis (HR: 4.13, 95% CI: 1.22-13.94, P = 0.022).

Conclusions: ASCC patients with distant metastasis at multiple sites were a worse prognosis. In addition, early recurrence was identified as an independent prognostic factor for OS among ASCC patients.

Objectives: We aimed to identify risk factors for postoperative recurrence (PR) after Altemeier's and Delorme's procedures for full-thickness rectal prolapse (FTRP).

Methods: We enrolled 127 patients who underwent Altemeier's and Delorme's procedures for FTRP between April 2008 and September 2021. We divided the 127 patients into recurrence and non-recurrence groups and conducted univariate and multivariate analyses. We used six independent variables: age, body mass index (BMI), history of surgical repair for FTRP, coexistence of prolapse in other organs, poor fixation of the rectum on defecography before surgery, length of the prolapsed rectum, and type of surgical procedure (Altemeier's or Delorme's procedures).

Results: PR developed in 51 (40.1%) patients during a mean follow-up period of 453 (range, 9-3616) days. Comparing the recurrence group (n=51) with the non-recurrence group (n=76), significant difference was observed regarding the coexistence of prolapse in other organs (p=0.017) in the univariate analysis. In the multivariate analysis, significant differences were observed in BMI (OR 1.18, 95% CI 1.030-1.350, p=0.020), coexistence of prolapse in other organs (OR 3.38, 95% CI 1.200-9.500, p=0.021), length of the prolapsed rectum (OR 1.030, 95% CI 1.010-1.060, p=0.015), poor fixity of the rectum on defecography (OR 0.332, 95% CI 0.129-0.852, p=0.022), and surgical procedures (OR 0.192, 95% CI 0.064-0.573, p=0.003).

Conclusions: The study suggested that increasing BMI, coexistence of prolapse in other organs, length of the prolapsed rectum, poor fixation of the rectum on defecography before surgery, and types of surgical procedure might be risk factors of PR after perineal surgery for FTRP.

Objectives: To compare patients' self-administered responses to the Fecal Incontinence Severity Index (FISI) questionnaire (A1) with their responses to physician's oral interview (A3).

Methods: Patients (n=100: mean age: 72 years; 66 women) with FI completed the FISI and the modified FISI (with written explanations) questionnaires, followed by a physician interview. To identify a threshold for the rating gap between A1 and A3, we calculated each patient's mean difference in the FISI scores.

Results: There was no significant difference in the FISI scores between A1 and A3. A rating gap existed in the FISI scores (mean difference=8.9). It occurred in 37% of the patients, making its threshold 9. Multivariate analysis revealed that older age and no history of pelvic floor surgery were independently associated with the presence of a rating gap in the FISI scores. The in-coincidence of ticked boxes to all types of leakage between the self-administered responses and those by physician's oral history was 49% (197/400). Older age was associated with the in-coincidence of a ticked box between the assessment results of gas or solid stool leakage.

Conclusions: Some non-negligible discrepancy existed between patients' self-administered responses and their responses to physician's oral interview, especially in older patients.

Objectives: This study aimed to investigate the impact of the COVID-19 pandemic on the examination and treatment of colorectal cancer (CRC) and on the behaviors of patients and practitioners.

Methods: This is a retrospective analysis of the CRC patients who presented to our department between April 2019 and March 2021 and underwent surgery. Clinical presentation of CRC and time from symptom onset to medical presentation were compared between the control (April 2019 to March 2020, n=124) and COVID-19 pandemic periods (April 2020 to March 2021, n=111).

Results: Two hundred and thirty-five patients were reviewed. The rate of positive fecal occult blood tests was significantly lower during the COVID-19 pandemic period (13.5 vs. 25.0%, P = 0.027). Among the symptomatic patients who had melena and abdominal symptoms, the time from symptom onset to medical presentation was significantly longer during the COVID-19 period (115 vs. 31 days, P < 0.001). In addition, the interval between presenting to a practitioner and being referred to our department was similar between the two periods (19 vs. 13 days, P = 0.092). There were no significant differences in the stage of cancer between the two periods. The rate of preoperative sub-obstruction was significantly higher during the COVID-19 period (41.4 vs 23.4%, P = 0.003). There was no significant difference in overall survival and recurrence-free survival between two periods.

Conclusions: Hesitation to seek examination and treatment for CRC was observed in patients but not in practitioners during the COVID-19 pandemic period. The prognosis did not change.

Objectives: To clarify whether self-expandable metallic stent (SEMS) placement for obstructive colorectal cancer (CRC) increases perineural invasion (PNI), thereby worsening the prognosis.

Methods: In total, 1022 patients with pathological T3 or T4 colon or rectosigmoid cancer who underwent resection were retrospectively reviewed. The study patients were divided into a no obstruction group (n=693), obstruction without stent group (n=251), and obstruction with stent group (n=78), and factors demonstrating an independent association with PNI, the difference in PNI incidence and severity between groups, and the association between PNI and the duration from SEMS placement to surgery were investigated. Survival analysis was performed for each group.

Results: On multivariate analysis, SEMS placement (hazard ratio [HR]: 2.08) was independently associated with PNI whereas SEMS placement was not.

PNI occurred in 39%, 45%, and 68% of the no obstruction, obstruction without stent, and obstruction with stent group, respectively. In the obstruction with stent group, the proportion of PNI was not associated with the duration from SEMS placement to surgery. Extramural PNI, an advanced form of PNI, demonstrated no increase with increasing interval. The five-year OS was 86.3%, 76.7%, and 73.1% in no obstruction, obstruction without stent, and obstruction with stent group, respectively. On multivariate analysis, obstruction was an independent risk factor of decreased OS (HR: 1.57) whereas SEMS placement was not.

Conclusions: The prognosis was comparable between patients with SEMS placement and those with an obstruction who did not undergo SEMS placement, thus demonstrating that SEMS is a viable, therapeutic option for BTS.

Objectives: Delayed bleeding is the most frequent adverse event associated with endoscopic mucosal resection (EMR) and hot snare polypectomy (HSP) of colorectal polyps. However, whether the incidence of delayed bleeding differs between outpatient and inpatient treatment is unknown. Therefore, in this study, we aimed to evaluate delayed bleeding rates between outpatient and inpatient endoscopic treatments and clarify the safety of outpatient treatment.

Methods: We enrolled 469 patients (1077 polyps) and 420 patients (1080 polyps) in the outpatient and inpatient groups, respectively, who underwent EMR or HSP for colorectal polyps at our institution between April 2020 and May 2023. Using propensity score matching, we evaluated the delayed bleeding rates between the two groups. Delayed bleeding was defined as a hemorrhage requiring endoscopic hemostasis occurring within 14 days of the procedure.

Results: Propensity score matching created 376 (954 polyps) matched patient pairs. The median maximum diameter of polyps removed was 10 mm in both groups. Delayed bleeding rates per patients were 1.3% (5/376) in the outpatient group and 2.9% (11/376) in the inpatient group (P=0.21). In term of per polyp, early delayed bleeding (occurring within 24 hours) rates were higher in the inpatient group than outpatient group (0.2% [2/954] vs. 1.1% [10/954], respectively; P=0.04). No severe bleeding requiring a transfusion occurred in either group.

Conclusions: Outpatient endoscopic treatment did not increase delayed bleeding compared with inpatient treatment. Outpatient treatment would be safe and common for the removal of colorectal polyps.

Objectives: Artificial intelligence (AI) with white light imaging (WLI) is not enough for detecting non-polypoid colorectal polyps and it still has high false positive rate (FPR). We developed AIs using blue laser imaging (BLI) and linked color imaging (LCI) to detect them with specific learning sets (LS).

Methods: The contents of LS were as follows, LS (WLI): 1991 WLI images of lesion of 2-10 mm, LS (IEE): 5920 WLI, BLI, and LCI images of non-polypoid and small lesions of 2-20 mm. LS (IEE) was extracted from videos and included both in-focus and out-of-focus images. We designed three AIs as follows: AI (WLI) finetuned by LS (WLI), AI (IEE) finetuned by LS (WLI)+LS (IEE), and AI (HQ) finetuned by LS (WLI)+LS (IEE) only with images in focus. Polyp detection using a test set of WLI, BLI, and LCI videos of 100 non-polypoid or non-reddish lesions of 2-20 mm and FPR using movies of 15 total colonoscopy were analyzed, compared to 2 experts and 2 trainees.

Results: The sensitivity for LCI in AI (IEE) (83%) was compared to that for WLI in AI (IEE) (76%: p=0.02), WLI in AI (WLI) (57%: p<0.01), BLI in AI (IEE) (78%: p=0.14), and LCI in trainees (74%: p<0.01). The sensitivity for LCI in AI (IEE) (83%) was significantly higher than that in AI (HQ) (78%: p<0.01). The FPR for LCI (6.5%) in AI (IEE) were significantly lower than that in AI (HQ) (17.3%: p<0.01).

Conclusions: AI finetuned by appropriate LS detected non-reddish and non-polypoid polyps under LCI.

Objectives: Excisional hemorrhoidectomy (EH) is sometimes same-day surgery under local anesthesia (LA); however, the LA injection can be painful. We conducted an open-label, crossover, randomised controlled trial to evaluate the efficacy and safety of pre-cooling in reducing pain associated with LA injection.

Methods: Patients aged ≥ 20 years undergoing bilateral EH were randomly assigned to 1 of 2 pre-cooling sequences: a cooling-first sequence and a cooling-second sequence. In the first intervention phase, 2 minutes of pre-cooling was applied before LA injection in patients randomized to the cooling-first sequence; patients in the cooling-second sequence were asked to wait for 2 minutes (without pre-cooling) before LA injection. The pre-cooling sequences and the perianal sides targeted for injection were reversed in the second intervention phase. The primary outcome was the visual analogue scale (VAS) rating for pain from LA injection, which was obtained twice for each patient. Adverse events due to pre-cooling (e.g., skin disorders) were documented.

Results: Of 114 screened patients, 51 were randomized to the cooling-first (n = 26; analyzed: n = 26) or cooling-second sequence (n = 25; analyzed: n = 25). The 2-minute pre-cooling was completed by 48 patients (94%). VAS scores for LA injection pain decreased significantly with pre-cooling compared to without (difference estimate, −1.71; 95% confidence interval, −2.12 to −1.31; p< 0.001). No adverse events were reported.

Conclusions: Two minutes of skin pre-cooling effectively and safely reduces LA injection pain in patients undergoing EH.

Objectives: Hand-assisted laparoscopic surgery (HALS) combines the benefits of laparoscopic surgery with the tactile feedback from open surgery. In the current era of laparoscopic surgery, the significance of HALS as a technical transition has diminished. This study clarified the usefulness of HALS in restorative proctocolectomy (RPC) for ulcerative colitis (UC) in the era of laparoscopic surgery.

Methods: The 212 patients who underwent RPC with ileal pouch-anal anastomosis between 2007 and 2023 were included in this study. The patients were divided into three groups, open surgery (OS), HALS, and conventional laparoscopic surgery (LAP), and their characteristics, surgical outcomes, surgical complications, and functional outcomes were compared.

Results: The number of surgical techniques was OS in 21 cases, HALS in 184 cases, and LAP in 7 cases. The number of surgeons was two for OS and HALS, and four for LAP, with OS and HALS having fewer surgeons than LAP. The length of the skin incision was 13, 7, and 3 cm for OS, HALS, and LAP, respectively, and the operation times was 250, 286, and 576 minutes for OS, HALS, and LAP, respectively, with LAP having the longest operation time. The postoperative complications and function did not differ markedly among the three groups.

Conclusions: In RPC for UC, HALS involved fewer surgeons and a shorter operative time than LAP. Even in the era of laparoscopic surgery, HALS remains a useful option, especially when a shorter operation time is required or when the number of available surgeons is insufficient.

Objectives: The aim of this study was to identify the microbiota whose decrease in tumor area was associated with the metastatic process of distal colorectal cancer (CRC).

Methods: Twenty-eight consecutive patients with distal CRC undergoing surgical resection in our hospital were enrolled. Microbiota in 28 specimens from surgically resected colorectal cancers were analyzed using 16S ribosomal ribonucleic acid gene amplicon sequencing and the relative abundance (RA) of microbiota was evaluated. The densities of tumor-infiltrating lymphocytes (TIL) and tumor associated macrophages (TAM) in the colorectal cancers were immunohistochemically evaluated.

Results: Phocaeicola was the most abundant microbiota in normal mucosa. The RA of Phocaeicola in tumor tissues tended to be lower than that in normal mucosa although the difference was not significant (p=0.0732). The RA of Phocaeicola at tumor sites did not correlate either with depth of tumor invasion (pT-stage) or tumor size, however they were significantly reduced in patients with nodal metastases (p<0.05) and those with distant metastases (p<0.001). The RA of Phocaeicola at tumor sites showed positive correlation with the densities of CD3(+) or CD8(+) TIL. Since P. vulgatus was the most dominant species (47%) of the Phocaeicola, the RA of P. vulgatus and CRC metastasis and its association with TIL and TAM were also investigated. P. vulgatus showed a similar trend to genus Phocaeicola but was not statistically significant.

Conclusions: A relative reduction of Phocaeicola attenuates the local anti-tumor immune response in distal CRC, which may facilitate metastatic spread.

Background: The survival benefit of adjuvant chemotherapy after surgical resection of oligometastases from colorectal cancer (CRC) remains unclear. The prognostic role of circulating-tumor DNA (ctDNA) was reported recently and a risk stratification strategy based on monitoring minimal/molecular residual disease (MRD) has been proposed, however, which drug regimen is most effective for ctDNA-positive patients is unknown.

Methods/Design: Oligometastatic CRC patients planning to undergo surgery were registered in this study. After metastasectomy, the registered patients were enrolled in the treatment arm, in which 8 courses of modified-FOLFOXIRI (mFOLFOXIRI; irinotecan 150 mg/m², oxaliplatin 85 mg/m², l-leucovorin (l-LV) 200 mg/m², and 46-h continuous infusion of 5-fluorouracil (5-FU) 2400 mg/m² every 2 weeks) followed by 4 courses of 5-FU/l-LV are administered. The patients who did not meet the eligibility criteria for the treatment arm or did not consent to mFOLFOXIRI enrolled in the observation arm in which standard of care treatment is provided. Prospective blood collections for retrospective ctDNA analysis are scheduled pre-surgery, and at 28 days, 4 and 7 months after surgery. The primary endpoint is treatment compliance at 8 courses of mFOLFOXIRI and the key secondary endpoints are the ctDNA-positivity rate and survival outcomes in ctDNA-positive and -negative groups. A total of 85 patients will be enrolled from 11 institutions. First patient-in was on July 2020. Accrual completed in February 2024.

Discussion: This study will potentially identify a better treatment strategy for patients with resectable oligometastatic CRC having postsurgical ctDNA positivity, compared to the current standard of care approaches.

In Japan, the hinotori™ Surgical Robot System obtained pharmaceutical approval for use in colorectal cancer surgery in October 2022. This system has an operating arm with eight axes, adjustable arm base, and flexible three-dimensional viewer, which are expected to be advantageous in colorectal cancer surgery. A 55-year-old man presented to our hospital with melena and was diagnosed with cStage IIA (cT3N0M0) rectal cancer. The patient underwent intersphincteric resection using hinotori™ Surgical Robot System. Appropriate port placement was available for rectal manipulation, lymph node dissection, and arm base angle adjustment. Herein, we report the world's first rectal cancer surgery using the hinotori™ Surgical Robot System with TaTME by two teams.

Lateral lymph node (LLN) metastasis in T1 rectal cancer has an incidence of less than 1%. However, its clinical features are largely uncharted. We report a case of LLN metastasis in T1 rectal cancer and review the relevant literature. A 56-year-old female underwent rectal resection for lower rectal cancer 2 years previously (pT1bN0M0). During follow-up, an elevated tumor marker CA19-9 was documented. Enhanced CT and MRI showed a round shape nodule 2 cm in size on the left side of pelvic wall. PET-CT showed high accumulation of FDG in the same lesion, leading to a diagnosis of isolated LLN recurrence. Because no other site of recurrence was detected, surgical resection of the LLN was performed. Microscopic findings were consistent with metastatic lymph node originating from the recent rectal cancer. Adjuvant chemotherapy for six months was given, and patient remains free of recurrent disease seven months after LLN resection. Although LLN recurrence after surgery for T1 rectal cancer is rare, post-surgical follow-up should not be omitted. When LLN metastasis is suspected on CT, MRI and/or PET-CT will be recommended. Surgical resection of LLN metastasis in patients with T1 rectal cancer may lead to favorable outcomes, when recurrence in other areas is not observed.