Endoscopic Artificial Intelligence for Image Analysis in Gastrointestinal Neoplasms.

BACKGROUND: Artificial intelligence (AI) using deep learning systems has recently been utilized in various medical fields. In the field of gastroenterology, AI is primarily implemented in image recognition and utilized in the realm of gastrointestinal (GI) endoscopy. In GI endoscopy, computer-aided detection/diagnosis (CAD) systems assist endoscopists in GI neoplasm detection or differentiation of cancerous or non-cancerous lesions. Several AI systems for colorectal polyps have already been applied in colonoscopy clinical practices. In esophagogastroduodenoscopy, a few CAD systems for upper GI neoplasms have been launched in Asian countries. The usefulness of these CAD systems in GI endoscopy has been gradually elucidated. SUMMARY: In this review, we outline recent articles on several studies of endoscopic AI systems for GI neoplasms, focusing on esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAC), gastric cancer (GC), and colorectal polyps. In ESCC and EAC, computer-aided detection (CADe) systems were mainly developed, and a recent meta-analysis study showed sensitivities of 91.2% and 93.1% and specificities of 80% and 86.9%, respectively. In GC, a recent meta-analysis study on CADe systems demonstrated that their sensitivity and specificity were as high as 90%. A randomized controlled trial (RCT) also showed that the use of the CADe system reduced the miss rate. Regarding computer-aided diagnosis (CADx) systems for GC, although RCTs have not yet been conducted, most studies have demonstrated expert-level performance. In colorectal polyps, multiple RCTs have shown the usefulness of the CADe system for improving the polyp detection rate, and several CADx systems have been shown to have high accuracy in colorectal polyp differentiation. KEY MESSAGES: Most analyses of endoscopic AI systems suggested that their performance was better than that of non-expert endoscopists and equivalent to that of expert endoscopists. Thus, Endoscopic AI systems may be useful for reducing the risk of overlooking lesions and improving the diagnostic ability of endoscopists.

Indoleamine 2,3-Dioxygenase Inhibitor Suppresses Colon Cancer Cell Migration, Invasion, and Epithelial-Mesenchymal Transition.

BACKGROUND/AIM: Indoleamine 2,3-dioxygenase 1 (IDO1) is a key enzyme in tryptophan metabolism and plays an important role in immunosuppression. The effects of IDO1 on tumor invasion and metastasis have been studied in several types of malignancies. However, the role of IDO1 in these steps in colorectal cancer (CRC) has not been elucidated. Therefore, we aimed to investigate the effects of IDO1 on invasion, migration, and epithelial-mesenchymal transition (EMT) in CRC cells. MATERIALS AND METHODS: All experiments were performed using the DLD-1 colon cancer cell line that expresses IDO1. We conducted a scratch wound healing assay and Boyden chamber assay to investigate the impact of IDO1 on DLD-1 cell migration and invasion, respectively, in the presence and absence of the IDO1 inhibitor L-1-methyl-tryptophan (L-1-MT). Additionally, western blotting was performed to analyze alterations in the expression of EMT-related markers caused by L-1-MT. RESULTS: High expression of IDO1 was confirmed in the cytoplasm of DLD-1 by immunofluorescence staining. In the scratch wound healing assay, the invasion ability of DLD-1 cells decreased to 62% after treatment with L-1-MT at 1,000 µM for 24 h. In the Boyden chamber assay, the migration of DLD-1 cells was suppressed by 85% after treatment with L-1-MT at 2,500 µM for 24 h. L-1-MT treatment increased the expression level of E-cadherin and decreased the expression levels of vimentin, Snail, and Slug. CONCLUSION: IDO1 inhibition reduced the invasion and migration ability of IDO1-expressing DLD-1 colon cancer cells, which was accompanied by altered expression of EMT-related proteins. IDO1 could be a potential target for the treatment of advanced CRC.

Possible poor prognosis in younger-onset Crohn's disease-associated anorectal cancer: A subanalysis of the Nationwide Japanese study.

Background and aims: Crohn's disease (CD)-associated intestinal cancers are characterized by their high incidence, particularly at the anorectal site in the Japanese population. Accumulating evidence revealed that younger-onset sporadic colorectal cancer may exhibit unique biological features. To the best of our knowledge, few previous articles reported clinicopathological features in patients with CD-associated anorectal cancer (CDAAC). Therefore, we aimed to clarify the relationship between the younger onset of cancer and clinicopathological characteristics and prognosis, and the efficacy of cancer surveillance in patients with CDAAC. Methods: CD patients who had been diagnosed with intestinal cancers from 1983 to 2020 were collected from 39 Japanese institutions in this study. Of 316 patients with CD-associated intestinal cancers, we analyzed 211 patients with CDAAC. We divided the patients into two groups according to the median age at cancer diagnosis (45 years old). Results: Younger-onset CDAAC (YO-CDAAC) patients were significantly more likely to have a poor outcome than those with older-onset CDAAC (OO-CDAAC) in terms of both disease-free survival (DFS) (p = 0.0014) and overall survival (OS) (p = 0.023). Multivariate analysis showed that age under 45 years old at diagnosis of cancer was one of the independent factors for poor DFS and OS (hazard ratios: 2.15, 95% confidence interval: 1.09-4.26, p = 0.028, hazard ratios: 1.95, 95% confidence interval: 1.05-3.60, p = 0.033, respectively). Patients detected via surveillance showed significantly better DFS and OS rates than symptomatic patients in YO-CDAAC (p = 0.012 and 0.0031, respectively). Conclusions: YO-CDAAC may have a poorer prognosis compared with OO-CDAAC. Surveillance could be important to improve cancer prognosis, especially in young CD patients with anorectal disease.

Long-term Outcome After Surgical Resection of Paraaortic Lymph Node Metastasis of Colorectal Cancer: A Multicenter Retrospective Study.

BACKGROUND: The significance of resection of paraaortic lymph node metastasis in colorectal cancer is controversial. OBJECTIVE: To clarify the prognosis of colorectal cancer after paraaortic lymph node metastasis resection. DESIGN: Multicenter retrospective study. SETTINGS: Thirty-six institutions in Japan participated in this study. PATIENTS: Patients with resected and pathologically proven paraaortic lymph node metastasis of CRC between 2010 and 2015. DATA SOURCES: Database and medical records at each institution. MAIN OUTCOME MEASURES: Overall survival after paraaortic lymph node metastasis resection, recurrence-free survival, and recurrence patterns after R0 resection of paraaortic lymph node metastasis. RESULTS: A total of 133 patients were included in the primary analysis population in this study. The 5-year overall survival rate (95% confidence interval [CI]) was 41.0% (32.0, 49.8), and the median survival (95% CI) was 4.1 (3.4, 4.7) years. Independent prognostic factors for overall survival were the pathological T stage (pT4 vs. pT1- 3, adjusted hazard ratio [aHR]: 1.91, p = 0.006), other organ metastasis (present vs. absent, aHR: 1.98, p = 0.005), time to metastases (synchronous vs. metachronous, aHR: 2.02, p = 0.02), and number of paraaortic lymph node metastasis (≥3 vs. <3, aHR: 2.13, p = 0.001). The 5-year recurrence-free survival rate (95% CI) was 21.1% (13.5, 29.7), with a median (95% CI) of 1.2 (0.9, 1.4) years. The primary tumor location (left- vs. right-sided colon, aHR: 4.77, p = 0.01; rectum vs. right-sided colon, aHR: 5.27, p = 0.006), other organ metastasis (present vs. absent, aHR: 1.90, p = 0.03), number of paraaortic lymph node metastasis (≥3 vs. <3, aHR: 2.20, p = 0.001), and hospital volume (<10 vs. ≥10, aHR: 2.18, p = 0.02) were identified as independent prognostic factors for recurrence-free survival. Paraaortic lymph node recurrence was the most common at 33.3%. LIMITATIONS: Selection bias cannot be ruled out because of the retrospective nature of the study. CONCLUSIONS: Less than three paraaortic lymph node metastasis was a favorable prognostic factor for both overall survival and recurrence-free survival. However, paraaortic lymph node metastases were considered to be a systemic disease and the significance of resection was limited. See Video Abstract.

Robotic Versus Laparoscopic Abdominoperineal Resection for Locally Advanced Rectal Cancer Following Preoperative Chemoradiotherapy.

BACKGROUND/AIM: The usefulness of robotic surgery compared to laparoscopic surgery for rectal cancer has been reported; however, few reports exist on robotic abdominoperineal resection (APR). The aim of this study was to compare the outcomes of robotic and laparoscopic surgery to determine their usefulness in patients with locally advanced rectal cancer who had undergone preoperative chemoradiotherapy (CRT). PATIENTS AND METHODS: This retrospective study included 43 patients with locally advanced rectal cancer who underwent preoperative CRT and robotic (22 patients) or laparoscopic APR (21 patients) between December 2012 and September 2022. We examined the short- and long-term outcomes in the robotic and laparoscopic groups. RESULTS: The median follow-up durations were 36 and 48 months for the robotic and laparoscopic groups, respectively. No significant differences in operative time, intraoperative blood loss, or overall complication rates were observed. However, the incidence of organ/space surgical site infection (SSI) was significantly lower in the robotic surgery group than in the laparoscopic group (9.1% vs. 38.1%, p=0.034) and the 3-year overall survival rate was significantly higher in the robotic surgery group than in the laparoscopic group (95% vs. 67%, p=0.029). CONCLUSION: Robotic APR was associated with a significantly lower rate of organ/space SSIs than the laparoscopic approach, indicating the usefulness of the robotic approach.

Long-Term Outcomes of Additional Surgery After Endoscopic Resection Versus Primary Surgery for T1 Colorectal Cancer.

INTRODUCTION: There is considerable concern about whether endoscopic resection (ER) before additional surgery (AS) for T1 colorectal cancer (CRC) has oncologically potential adverse effects. Therefore, the aim of this study was to compare the long-term outcomes, including overall survival (OS), of patients treated with AS after ER vs primary surgery (PS) for T1 CRC using a propensity score-matched analysis from a large observational study. METHODS: This study investigated 6,105 patients with T1 CRC treated with either ER or surgical resection between 2009 and 2016 at 27 high-volume Japanese institutions, with those undergoing surgery alone included in the PS group and those undergoing AS after ER included in the AS group. Propensity score matching was used for long-term outcomes of mortality and recurrence analysis. RESULTS: After propensity score matching, 1,219 of 2,438 patients were identified in each group. The 5-year OS rates in the AS and PS groups were 97.1% and 96.0%, respectively (hazard ratio: 0.72, 95% confidence interval: 0.49-1.08), indicating the noninferiority of the AS group. Moreover, 32 patients (2.6%) in the AS group and 24 (2.0%) in the PS group had recurrences, with no significant difference between the 2 groups (odds ratio: 1.34, 95% confidence interval: 0.76-2.40, P = 0.344). DISCUSSION: ER before AS for T1 CRC had no adverse effect on patients' long-term outcomes, including the 5-year OS rate. ER is a viable first-line treatment option for endoscopically resectable T1 CRC.

Evaluation of output factors of different radiotherapy planning systems using Exradin W2 plastic scintillator detector.

This study aims to evaluate the output factors (OPF) of different radiation therapy planning systems (TPSs) using a plastic scintillator detector (PSD). The validation results for determining a practical field size for clinical use were verified. The implemented validation system was an Exradin W2 PSD. The focus was to validate the OPFs of the small irradiation fields of two modeled radiation TPSs using RayStation version 10.0.1 and Monaco version 5.51.10. The linear accelerator used for irradiation was a TrueBeam with three energies: 4, 6, and 10 MV. RayStation calculations showed that when the irradiation field size was reduced from 10 × 10 to 0.5 × 0.5 cm2, the results were within 2.0% of the measured values for all energies. Similarly, the values calculated using Monaco were within approximately 2.0% of the measured values for irradiation field sizes between 10 × 10 and 1.5 × 1.5 cm2 for all beam energies of interest. Thus, PSDs are effective validation tools for OPF calculations in TPS. A TPS modeled with the same source data has different minimum irradiation field sizes that can be calculated. These findings could aid in verification of equipment accuracy for treatment planning requiring highly accurate dose calculations and for third-party evaluation of OPF calculations for TPS.

Nutritional Status Indicators Predict Tolerability to Adjuvant Chemotherapy in Patients with Stage II/III Rectal Cancer Undergoing Neoadjuvant Chemoradiotherapy.

INTRODUCTION: Adjuvant chemotherapy (AC) after radical surgery following preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC) is now the standard of care. The identification of risk factors for the discontinuation of AC is important for further improvements in survival. We herein examined the prognostic impact of chemotherapy compliance and its relationship with the prognostic nutritional index (PNI) before surgery. METHODS: A total of 335 stage II-III LARC patients who underwent preoperative CRT between 2003 and 2022 at the University of Tokyo Hospital were retrospectively reviewed. We excluded patients with recurrence during AC and those who had not received AC. The relationship between AC and long-term outcomes and that between PNI values and the duration of AC were examined. RESULTS: Thirty-one patients discontinued AC and 62 continued AC. Recurrence-free survival (RFS) was significantly shorter in patients who discontinued AC (p = 0.0056). The discontinuation of AC was identified as an independent risk factor for RFS (hazard ratio [HR]: 2.24, p = 0.0233). Twenty-one patients were classified as having low PNI (less than 40), which correlated with an older age, low body mass index, and incomplete AC. Low PNI was an independent risk factor for a shorter duration of AC (HR: 2.53, p = 0.0123). CONCLUSION: The discontinuation of AC was related to poor RFS in patients with LARC undergoing preoperative CRT. Furthermore, a low PNI value was identified as a risk factor for a shorter duration of AC.

Minimally invasive versus open multivisceral resection for rectal cancer clinically invading adjacent organs: a propensity score-matched analysis.

BACKGROUND: Minimally invasive surgery (MIS), such as laparoscopic and robotic surgery for rectal cancer, is performed worldwide. However, limited information is available on the advantages of MIS over open surgery for multivisceral resection for cases clinically invading adjacent organs. PATIENTS AND METHODS: This was a retrospective propensity score-matching study of consecutive clinical T4b rectal cancer patients who underwent curative intent surgery between 2006 and 2021 at the University of Tokyo Hospital. RESULTS: Sixty-nine patients who underwent multivisceral resection were analyzed. Thirty-three patients underwent MIS (the MIS group), while 36 underwent open surgery (the open group). Twenty-three patients were matched to each group. Conversion was required in 2 patients who underwent MIS (8.7%). R0 resection was achieved in 87.0% and 91.3% of patients in the MIS and open groups, respectively. The MIS group had significantly less blood loss (170 vs. 1130 mL; p < 0.0001), fewer Clavien-Dindo grade ≥ 2 postoperative complications (30.4% vs. 65.2%; p = 0.0170), and a shorter postoperative hospital stay (20 vs. 26 days; p = 0.0269) than the open group. The 3-year cancer-specific survival rate, relapse-free survival rate, and cumulative incidence of local recurrence were 75.7, 35.9, and 13.9%, respectively, in the MIS group and 84.5, 45.4, and 27.1%, respectively, in the open group, which were not significantly different (p = 0.8462, 0.4344, and 0.2976, respectively). CONCLUSION: MIS had several short-term advantages over open surgery, such as lower complication rates, faster recovery, and a shorter hospital stay, in rectal cancer patients who underwent multivisceral resection.

Evaluation of anorectal function using real-time tissue elastography before and after preoperative chemoradiotherapy.

PURPOSE: This study aimed to clarify the relationship between changes in elasticity and anorectal function before and after chemoradiotherapy. METHODS: This is a single-center prospective cohort study (Department of Surgical Oncology, The University of Tokyo). We established a technique to quantify internal anal sphincter hardness as elasticity using transanal ultrasonography with real-time tissue elastography. Twenty-seven patients with post-chemoradiotherapy rectal cancer during 2019-2022 were included. Real-time tissue elastography with transanal ultrasonography was performed before and after chemoradiotherapy to measure internal anal sphincter hardness as "elasticity" (hardest (0) to softest (255); decreased elasticity indicated sclerotic changes). The relationship between the increase or decrease in elasticity pre- and post-chemoradiotherapy and the maximum resting pressure, maximum squeeze pressure, and Wexner score were the outcome measures. RESULTS: A decrease in elasticity was observed in 16/27 (59.3%) patients after chemoradiotherapy. Patients with and without elasticity decrease after chemoradiotherapy comprised the internal anal sphincter sclerosis and non-sclerosis groups, respectively. The maximum resting pressure post-chemoradiotherapy was significantly high in the internal anal sphincter sclerosis group (63.0 mmHg vs. 47.0 mmHg), and a majority had a worsening Wexner score (60.0% vs. 18.2%) compared with that of the non-sclerosis group. Decreasing elasticity (internal anal sphincter sclerosis) correlated with a higher maximum resting pressure (r = 0.36); no correlation was observed between the degree of elasticity change and maximum squeeze pressure. CONCLUSION: Internal anal sphincter sclerosis due to chemoradiotherapy may correlate to anorectal dysfunction.

Modified neoadjuvant rectal score as a novel prognostic model for rectal cancer patients who underwent chemoradiotherapy.

BACKGROUND: The neoadjuvant rectal score (NAR score) has recently been proposed as a better prognostic model than the conventional TNM classification for rectal cancer patients that have undergone neoadjuvant chemoradiotherapy. We recently developed an apoptosis-detection technique for assessing the viability of residual tumors in resected specimens after chemoradiotherapy. This study aimed to establish an improved prognostic classification by combining the NAR score and the assessment of the apoptosis of residual cancer cells. METHODS: We retrospectively enrolled 319 rectal cancer patients who underwent chemoradiotherapy followed by radical surgery. The recurrence-free survival and overall survival of the four models were compared: TNM stage, NAR score, modified TNM stage by re-staging according to cancer cell viability, and modified NAR score also by re-staging. RESULTS: Downstaging of the ypT stage was observed in 15.5% of cases, whereas only 4.5% showed downstaging of ypN stage. C-index was highest for the modified NAR score (0.715), followed by the modified TNM, TNM, and NAR score. Similarly, Akaike's information criterion was smallest in the modified NAR score (926.2), followed by modified TNM, TNM, and NAR score, suggesting that the modified NAR score was the best among these four models. The overall survival results were similar: C-index was the highest (0.767) and Akaike's information criterion was the smallest (383.9) for the modified NAR score among the four models tested. CONCLUSION: We established a novel prognostic model, for rectal cancer patients that have undergone neoadjuvant chemoradiotherapy, using a combination of apoptosis-detecting immunohistochemistry and neoadjuvant rectal scores.

Differences in the Difficulty of Accessing Various 3-Dimensional Locations Under Mirror-Image Conditions During Laparoscopic Surgery.

BACKGROUND: Laparoscopic colon surgery frequently requires performing maneuvers under mirror-images conditions; the complexity differs depending on the surgical site location in the abdominal cavity. However, no previous reports have examined this. METHODS: Eleven surgeons participated in this study. Operations were performed on 25 points placed at the bottom and sides of a laparoscopic training box under mirror-image conditions. The mean time-point required to operate at each point and variation between surgeons were evaluated. RESULTS: When the right hand was used, time-points to touch the right side-superficial ends were 0.50 to 0.58 and 0.27 to 0.45 for the other sites. With the left hand, time-points to touch the left side-superficial ends were 0.58 to 0.63 and 0.28 to 0.51 for the other sites, indicating that the most difficult manipulation was at the proximal site of the surgical port. The variation in the difficulty according to the spots increased with a decrease in the surgeon's experience (right hand, r =-0.248; left hand, r =-0.491). CONCLUSIONS: In performing laparoscopic surgery under mirror-image conditions, the technical difficulty varies by location, and operating in locations close to the forceps port is the most difficult.

Local excision versus radical surgery for anal squamous cell carcinoma: a multicenter study in Japan.

BACKGROUND: The standard treatment for anal squamous cell carcinoma is chemoradiation therapy (CRT), but there is a possibility of over-treatment for early-stage disease. cTisN0 and cT1N0 disease is currently indicated for local excision, but it is unclear whether the indication of local excision can be expanded to cT2N0 disease. METHODS: 126 patients with cTis-T2N0 anal cancer treated at 47 centers in Japan between 1991 and 2015 were included. Patients were first classified into the CRT group and surgical therapy group according to the initial therapy, and the latter was further divided into local excision (LE) and radical surgery (RS) groups. We compared prognoses among the groups, and analyzed risk factors for recurrence after local excision. RESULTS: The CRT group (n = 87) and surgical therapy group (n = 39) showed no difference in relapse-free survival (p = 0.29) and overall survival (p = 0.94). Relapse-free survival curves in the LE (n = 23) and RS groups (n = 16) overlapped for the initial 3 years, but the curve for the LE group went lower beyond (p = 0.33). By contrast, there was no difference in overall survival between the two groups (p = 0.98). In the LE group, the majority of recurrences distributed in locoregional areas, which could be managed by salvage treatments. Muscular invasion was associated with recurrence after local excision (hazard ratio: 22.91, p = 0.011). CONCLUSION: LE may be applied to selected patients with anal cancer of cTis-T2N0 stage. Given the high risk of recurrence in cases with muscular invasion, it may be important to consider close surveillance and additional treatment in such patients.

Treatment Decision for Locally Resected T1 Colorectal Carcinoma-Verification of the Japanese Guideline Criteria for Additional Surgery Based on Long-Term Clinical Outcomes.

INTRODUCTION: To verify the value of the pathological criteria for additional treatment in locally resected pT1 colorectal carcinoma (CRC) which have been used in the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines since 2009. METHODS: We enrolled 4,719 patients with pT1 CRC treated at 27 institutions between July 2009 and December 2016 (1,259 patients with local resection alone [group A], 1,508 patients with additional surgery after local resection [group B], and 1,952 patients with surgery alone [group C]). All 5 factors of the JSCCR guidelines (submucosal resection margin, tumor histologic grade, submucosal invasion depth, lymphovascular invasion, and tumor budding) for lymph node metastasis (LNM) had been diagnosed prospectively. RESULTS: Any of the risk factors were present in 3,801 patients. The LNM incidence was 10.3% (95% confidence interval 9.3-11.4) in group B/C patients with risk factors, whereas it was 1.8% (95% confidence interval 0.4-5.2) in those without risk factors ( P < 0.01). In group A, the incidence of recurrence was 3.4% in patients with risk factors, but it was only 0.1% in patients without risk factors ( P < 0.01). The disease-free survival rate of group A patients classified as risk positive was significantly worse than those of groups B and C patients. However, the 5-year disease-free survival rate in group A patients with no risk was 99.2%. DISCUSSION: Our large-scale real-world multicenter study demonstrated the validity of the JSCCR criteria for pT1 CRC after local resection, especially regarding favorable outcomes in patients with low risk of LNM.

Exploratory Biomarker Analysis Using Plasma Angiogenesis-Related Factors and Cell-Free DNA in the TRUSTY Study: A Randomized, Phase II/III Study of Trifluridine/Tipiracil Plus Bevacizumab as Second-Line Treatment for Metastatic Colorectal Cancer.

BACKGROUND: The TRUSTY study evaluated the efficacy of second-line trifluridine/tipiracil (FTD/TPI) plus bevacizumab in metastatic colorectal cancer (mCRC). OBJECTIVE: This exploratory biomarker analysis of TRUSTY investigated the relationship between baseline plasma concentrations of angiogenesis-related factors and cell-free DNA (cfDNA), and the efficacy of FTD/TPI plus bevacizumab in patients with mCRC. PATIENTS AND METHODS: The disease control rate (DCR) and progression-free survival (PFS) were compared between baseline plasma samples of patients with high and low plasma concentrations (based on the median value) of angiogenesis-related factors. Correlations between cfDNA concentrations and PFS were assessed. RESULTS: Baseline characteristics (n = 65) were as follows: male/female, 35/30; median age, 64 (range 25-84) years; and RAS status wild-type/mutant, 29/36. Patients in the hepatocyte growth factor (HGF)-low and interleukin (IL)-8-low groups had a significantly higher DCR (risk ratio [95% confidence intervals {CIs}]) than patients in the HGF-high (1.83 [1.12-2.98]) and IL-8-high (1.70 [1.02-2.82]) groups. PFS (hazard ratio {HR} [95% CI]) was significantly longer in patients in the HGF-low (0.33 [0.14-0.79]), IL-8-low (0.31 [0.14-0.70]), IL-6-low (0.19 [0.07-0.50]), osteopontin-low (0.39 [0.17-0.88]), thrombospondin-2-low (0.42 [0.18-0.98]), and tissue inhibitor of metalloproteinase-1-low (0.26 [0.10-0.67]) groups versus those having corresponding high plasma concentrations of these angiogenesis-related factors. No correlation was observed between cfDNA concentration and PFS. CONCLUSION: Low baseline plasma concentrations of HGF and IL-8 may predict better DCR and PFS in patients with mCRC receiving FTD/TPI plus bevacizumab, however further studies are warranted. CLINICAL TRIAL REGISTRATION NUMBER: jRCTs031180122.

Risk of gastric adenoma and adenocarcinoma in patients with familial adenomatous polyposis in Japan: a nationwide multicenter study.

BACKGROUND: Patients with familial adenomatous polyposis (FAP) have an increased risk of developing gastric neoplasms. However, the clinical course of FAP with these gastric lesions has not yet been fully clarified. The present study aimed to clarify the changes in the incidence risk of developing gastric adenoma or gastric cancer during the lifespan of patients with FAP. METHODS: Four hundred forty-three patients with data regarding gastric adenoma and gastric cancer retrospectively registered in a nationwide Japanese multicenter study were enrolled. The cumulative incidences and hazard rates (HRs) of gastric neoplasms were evaluated. RESULTS: The cumulative incidence rates in 50-year-old patients with FAP were 22.8% for gastric adenoma and 7.6% for gastric cancer, respectively. No significant association was found between gastric neoplasms and the colonic phenotype. The peak age for the HR of gastric adenoma was 65 years, with the highest HR (0.043). Regarding the incidence of gastric cancer, the HR increased moderately up to the age of 40 years, but the increase accelerated from the age of 50 years (HR = 0.0067). CONCLUSION: Careful surveillance of the upper gastrointestinal tract in elderly patients with FAP, such as shortening the interval of follow-up according to age, may be helpful for early diagnosis of gastric cancer.

Histological differentiation between sporadic and colitis-associated intestinal cancer in a nationwide study: A propensity-score-matched analysis.

BACKGROUND AND AIM: Colitis-associated intestinal cancer (CAC) can develop in patients with inflammatory bowel disease; however, the malignant grade of CAC may differ from that of sporadic colorectal cancer (CRC). Therefore, we compared histological findings distinct from cancer stage between CAC and sporadic CRC to evaluate the features of CAC. METHODS: We reviewed the clinical and histological data collected from a nationwide database in Japan between 1983 and 2020. Patient characteristics were compared to distinguish ulcerative colitis (UC), Crohn's disease (CD), and sporadic CRC. Comparisons were performed by using all collected data and propensity score-matched data. RESULTS: A total of 1077 patients with UC-CAC, 297 with CD-CAC, and 136 927 with sporadic CRC were included. Although the prevalence of well or moderately differentiated adenocarcinoma (Tub1 and Tub2) decreased according to tumor progression for all diseases (P < 0.01), the prevalence of other histological findings, including signet ring cell carcinoma, mucinous carcinoma, poorly differentiated adenocarcinoma, or squamous cell carcinoma, was significantly higher in CAC than in sporadic CRC. Based on propensity score-matched data for 982 patients with UC and 268 with CD, the prevalence of histological findings other than Tub1 and Tub2 was also significantly higher in those with CAC. At pT4, mucinous carcinoma occurred at a significantly higher rate in patients with CD (45/86 [52.3%]) than in those with sporadic CRC (13/88 [14.8%]) (P < 0.01). CONCLUSION: CAC, including early-stage CAC, has a higher malignant grade than sporadic CRC, and this difference increases in significance with tumor progression.

How Does Omitting Additional Surgery After Local Excision Affect the Prognostic Outcome of Patients With High-risk T1 Colorectal Cancer?

OBJECTIVE: To investigate how omitting additional surgery after local excision (LE) affects patient outcomes in high-risk T1 colorectal cancer (CRC). BACKGROUND: It is debatable whether additional surgery should be performed for all patients with high-risk T1 CRC regardless of the tolerability of invasive procedures. METHODS: Patients who had received LE for T1 CRC at the Japanese Society for Cancer of the Colon and Rectum institutions between 2009 and 2016 were analyzed. Those who had received additional surgical resection and those who did not were matched one-on-one by the propensity score-matching method. A total of 401 propensity score-matched pairs were extracted from 1975 patients at 27 Japanese Society for Cancer of the Colon and Rectum institutions and were compared. RESULTS: Regional lymph node metastasis was observed in 31 (7.7%) patients in the LE + surgery group. Comparatively, the incidence of oncologic adverse events was low in the LE-alone group, such as the 5-year cumulative risk of local recurrence (4.1%) or overall recurrence (5.5%). In addition, the difference in the 5-year cancer-specific survival between the LE + surgery and LE-alone groups was only 1.8% (99.7% and 97.9%, respectively), whereas the 5-year overall survival was significantly lower in the LE-alone group than in the LE + surgery group [88.5% vs 94.5%, respectively ( P = 0.002)]. CONCLUSIONS: Those who had decided to omit additional surgery at the dedicated center for CRC treatment presented a small number of oncologic events and a satisfactory cancer-specific survival, which may suggest an important role of risk assessment regarding nononcologic adverse events to achieve a best practice for each individual with high-risk T1 tumors.

Preoperative stoma site marking reduces postoperative stoma-related complications in emergency surgery: A single center retrospective cohort study.

BACKGROUND AND OBJECTIVE: Stoma site marking is an important factor in reducing stoma-related complications, thereby influencing the long-term quality of life in the elective setting. The impact of preoperative stoma site marking in emergency stoma creation is largely unknown. We aimed to determine whether preoperative stoma site marking in emergency stoma creation reduces stoma-related complications. METHODS: Patients who underwent emergency stoma creation at our hospital between 2009 and 2022 were examined by reviewing our prospective database and retrospective chart review. Subjects were classified into the "marking (+)" or "marking (-)" group according to stoma site marking (194 and 151 patients, respectively). The changes in the frequency of stoma marking over time and the effects of stoma marking on stoma-related complications were analyzed. RESULTS: The overall frequency of grade 2 or higher stoma-related complications was lower in the marking (+) group than in the marking (-) group (24% versus 36%, p = 0.010). Stoma site marking was associated with fewer soma site bleeding (2% versus 10%, p < 0.001), and the frequency of peristomal dermatitis was also lower (10%) in the marking (+) group (versus 18%, p = 0.042). Moreover, the lack of stoma site marking was an independent risk factor for overall stoma-related complications (adjusted odds ratio: 1.69, p = 0.034). CONCLUSIONS: Preoperative stoma site marking was associated with stoma-related complications in emergency surgery. The clinical significance of our attempt is worth validating with prospective studies.