Right-sided versus left-sided colorectal cancer in elderly patients: a sub-analysis of a large multicenter case-control study in Japan.

PURPOSE: This study investigated the impact of sidedness of colorectal cancer (CRC) in elderly patients on the prognosis. METHODS: In a sub-analysis of a multicenter case-control study of CRC patients who underwent surgery at ≥ 80 years old conducted in Japan between 2003 and 2007, both short- and long-term outcomes were compared between right-sided colon cancers (RCCs) and left-sided colorectal cancers (LCCs). RCCs were defined as those located from the cecum to the transverse colon. RESULTS: Among the 1680 patients who underwent curative surgery, 812 and 868 had RCCs and LCCs, respectively. RCCs were more frequent than LCCs in those who were female, had renal comorbidities, and had a history of abdominal surgery. Regarding tumor characteristics, RCCs were larger, invaded more deeply, and were diagnosed as either mucinous or signet ring-cell carcinoma more frequently than LCCs. Regarding the prognosis, patients with RCCs had a significantly longer cancer-specific survival (CS-S) and cancer-specific relapse-free survival (CS-RFS) than those with LCCs. Furthermore, sidedness was determined to be an independent prognostic factor for CS-S and CS-RFS. CONCLUSION: RCCs, which accounted for half of the cases in patients ≥ 80 years old, showed better long-term outcomes than LCCs.

Risk of Delayed Bleeding after Cold Snare Polypectomy in Patients with Antithrombotic Therapy.

BACKGROUND: Cold snare polypectomy is being increasingly adopted; however, there are few reports of cold snare polypectomy regarding antithrombotic therapy. AIMS: This study aimed to investigate the real-world safety of cold snare polypectomy during antithrombotic therapy. METHODS: We collected data from consecutive patients undergoing cold snare polypectomy in a single hospital between 2013 and 2017. Indications for cold snare polypectomy were any ≤ 10 mm polyp. The primary outcome was delayed bleeding. We compared rates of delayed bleeding between patients with and without antithrombotic therapy and analyzed risk factors for delayed bleeding using binary logistic regression model with firth procedure. RESULTS: In 2152 patients (mean age 67.6 years; male 1411), 4433 colorectal polyps (mean diameter 5.0 mm) underwent cold snare polypectomy. Clipping during the procedure was performed for 5.8%. Delayed bleeding occurred in 0.51% (11/2152) of patients and 0.25% (11/4433) of polyps, but no major delayed bleeding occurred. A total of 244 (11%) patients received antithrombotic therapy. Patients on antithrombotic therapy were older (p < 0.001), more likely male (p < 0.001) and had cold snare polypectomy in the proximal colon (p = 0.011). The rate of delayed bleeding was higher in patients on antithrombotic therapy (1.64% vs. non-antithrombotic therapy 0.37%, p = 0.009). Larger polyp size (> 5 mm), use of clips, and antithrombotic therapy were significant risk factors for delayed bleeding. There was no clear association between specific antithrombotic agents and delayed bleeding. CONCLUSIONS: Delayed bleeding after cold snare polypectomy was rare even in patients with antithrombotic therapy, and no major delayed bleeding occurred.

Prognostic factors of patients with left-sided obstructive colorectal cancer: post hoc analysis of a retrospective multicenter study by the Japan Colonic Stent Safe Procedure Research Group.

BACKGROUND: There are many reports on the choice of treatment for and prognosis of left-sided obstructive colorectal cancer; however, few studies have focused on the prognostic factors of left-sided obstructive colorectal cancer. Therefore, we analyzed the prognostic factors using a post hoc analysis of a retrospective multicenter study in Japan. METHODS: A total of 301 patients were enrolled in this study to investigate the prognostic factors for relapse-free survival. The relationships between sex, age, decompression for bridge to surgery, depth of invasion, lymph node metastasis, postoperative complications, adjuvant chemotherapy, carcinoembryonic antigen, carbohydrate antigen 19-9, neutrophil-to-lymphocyte ratio, and relapse-free survival were examined. RESULTS: No change in the decompression method, T3 cancer, negative postoperative complications (grades 0-1 of Clavien-Dindo classification), and adjuvant chemotherapy during Stage III indicated a significantly better prognosis in a Cox univariate analysis. Lymph node metastasis was not selected as a prognostic factor. Excluding patients with <12 harvested lymph nodes (possible stage migration), lymph node metastasis was determined as a prognostic factor. In a Cox multivariate analysis, change in the decompression method, depth of invasion, lymph node metastasis (excluding N0 cases with <12 harvested lymph nodes), and adjuvant chemotherapy were prognostic factors. CONCLUSIONS: Similar to those in nonobstructive colorectal cancer, depth of invasion and lymph node metastasis were prognostic factors in left-sided obstructive colorectal cancer, and patients with <12 dissected lymph nodes experienced stage migration. Stage migration may result in disadvantages, such as not being able to receive adjuvant chemotherapy.

[The Evaluation of Neoadjuvant Chemotherapy for Locally Advanced Rectal Cancer].

We evaluated the efficacy of neoadjuvant chemotherapy(NAC)for 38 patients with locally advanced rectal cancer (LARC). We administered mFOLFOX6 in 15, FOLFIRI in 3, CAPOX in 10, IRIS in 1 and FOLFOXIRI in 9 patients. We also used bevacizumab in 31 and panitumumab in 7 patients. There were 27 male and 11 female patients, with a median age of 64 years, and location was RS 2, Ra 9, Rb 21, and P 6. Synchronous distant metastasis was recognized in 13 patients. Nine patients had suffered adverse event of Grade 3, however all patients could complete NAC. Clinical response was CR 3, PR 31, SD 4, response rate was 91.9%, and reduction rate was 43.3(range 18.8-100)%. Clinical response of distant metastasis was CR 3, PR 9 and SD 1. Laparoscopic surgery was performed in 29 patients. Postoperative complications of Grade 2 of Clavien- Dindo classification were recognized in 14 and Grade 3 in 4 patients. Three- and five-year overall survival rate of 25 patients without distant metastasis were 79.6% and 74.9%, respectively; and 13 with distant metastasis were 61.6% and 52.6%, respectively. The efficacy, safety and postoperative outcomes of NAC for LARC are favorable, and we think that NAC will be one of the treatments for LARC.

Comparison of survival and perioperative outcome of the colonic stent and the transanal decompression tube placement and emergency surgery for left-sided obstructive colorectal cancer: a retrospective multi-center observational study "The CODOMO study".

PURPOSE: Advances in endoscopic technology have led to the reevaluation of self-expandable metallic stent (SEMS) placement as a bridge-to-surgery (BTS) in patients with obstructive colorectal cancer. In Japan, after inclusion of SEMS placement as a BTS in the medical insurance coverage in 2012, this procedure has been increasingly performed. However, a transanal decompression tube (TADT) placement has been used as a BTS. We aimed to retrospectively evaluate the optimal strategy for obstructive left-sided colorectal cancer (OLCRC) by comparing SEMS and TADT placement with emergency surgery. METHODS: We included 301 patients with stage II and III OLCRC from 27 institutions. The study patients were divided into Surgery group (emergency surgery, n = 103), SEMS group (BTS by SEMS, n = 113), and TADT group (BTS by TADT, n = 85). We compared the survival and perioperative outcomes of patients in the Surgery group as a standard treatment with those in the SEMS and TADT groups. RESULTS: The 3-year relapse-free survival rate in patients in the Surgery group was 74.8%, while that in patients in the SEMS group and TADT group were 69.0% (p = 0.39) and 55.3% (p = 0.006), respectively. The technical success rate was not statistically different, but the clinical success rate was significantly higher in the SEMS group than in the TADT group (p = 0.0040). With regard to postoperative complications after curative surgery, the SEMS group had significantly lower of complications (≥ grade 2) than the Surgery group (p = 0.022). CONCLUSION: Patients who underwent SEMS placement for OLCRC had similar oncological outcomes to patients who underwent emergency surgery.

Polyp detection algorithm can detect small polyps: Ex vivo reading test compared with endoscopists.

BACKGROUND AND STUDY AIMS: Small polyps are occasionally missed during colonoscopy. This study was conducted to validate the diagnostic performance of a polyp-detection algorithm to alert endoscopists to unrecognized lesions. METHODS: A computer-aided detection (CADe) algorithm was developed based on convolutional neural networks using training data from 1991 still colonoscopy images from 283 subjects with adenomatous polyps. The CADe algorithm was evaluated on a validation dataset including 50 short videos with 1-2 polyps (3.5 ± 1.5 mm, range 2-8 mm) and 50 videos without polyps. Two expert colonoscopists and two physicians in training separately read the same videos, blinded to the presence of polyps. The CADe algorithm was also evaluated using eight full videos with polyps and seven full videos without a polyp. RESULTS: The per-video sensitivity of CADe for polyp detection was 88% and the per-frame false-positive rate was 2.8%, with a confidence level of ≥30%. The per-video sensitivity of both experts was 88%, and the sensitivities of the two physicians in training were 84% and 76%. For each reader, the frames with missed polyps appearing on short videos were significantly less than the frames with detected polyps, but no trends were observed regarding polyp size, morphology or color. For full video readings, per-polyp sensitivity was 100% with a per-frame false-positive rate of 1.7%, and per-frame specificity of 98.3%. CONCLUSIONS: The sensitivity of CADe to detect small polyps was almost equivalent to experts and superior to physicians in training. A clinical trial using CADe is warranted.

A novel volume-reduced CT colonography regimen using hypertonic laxative (polyethylene glycol with ascorbic acid): randomized controlled trial.

OBJECTIVES: The aim of this study is to investigate the feasibility of bowel preparation using a hypertonic laxative (polyethylene glycol with ascorbic acid, PEG + Asc) for CT colonography (CTC) and to examine the volume limit of laxative. METHODS: In one institution, patients who met the indications for CTC were enrolled and randomly assigned to CTC with regimen A (800 ml PEG + Asc), B (600 ml PEG + Asc), or C (400 ml PEG + Asc). Sodium diatrizoate was given orally for fecal tagging. On the previous day, patients ate low-residue meals and took the assigned lavage solution after dinner. A reader blinded to the preparation graded residual stool/fluid and fecal tagging quality in six segments of the colorectum. The primary outcome was a proportion of colon segments without stool. One hundred twenty segments in 20 patients with each regimen were needed to show a non-inferiority margin of 15%, assuming 85% of no stool. RESULTS: A total of 360 segments in 60 patients were analyzed. There were 83% of segments with no stool in regimen A, 89% in regimen B, and 88% in regimen C. Using the delta method, the 95% confidence interval of the risk difference (6.7%) between regimens A and B was - 2.2% to 15.6%, and the risk difference (5.0%) between regimens A and C was - 4.1% to 14%, both within the non-inferiority margin. Residual fluid and fecal tagging quality were also within the non-inferiority margin. No adverse events occurred. CONCLUSIONS: A novel CTC regimen using hypertonic laxative demonstrated optimal colon cleansing effectiveness even with the lowest volume of laxative (UMIN000022851). KEY POINTS: • A novel CTC regimen using a hypertonic laxative is feasible. • The lowest volume of laxative provides excellent colon imaging. • However, the lowest volume of laxative did not improve patient acceptance.

[Two Cases of Advanced Colorectal Cancer Achieving Complete Response by FOLFOXIRI plus Bevacizumab-A Case Report].

We report 2 cases of advanced colorectal cancer achieving complete response by FOLFOXIRI plus bevacizumab. Case 1 was a 65-year-old male diagnosed with descending colon cancer with multiple liver metastases. Six courses of FOLFOXIRI plus bevacizumab were administered after laparoscopic-assisted left hemicolectomy. Ten partial hepatectomies and 1 radiofrequency ablation were performed as the liver metastases resolved. A pathological complete response was confirmed. Adjuvant chemotherapy was not administered, and recurrence-free survival was 21 months after hepatectomy. Case 2 was a 77-yearold male diagnosed with rectal cancer invading the pelvic wall and sacral foramen with bilateral lateral lymph node metastasis. Additionally, there was a cancer embolism in the right internal iliac vein. Six courses of FOLFOXIRI plus bevacizumab were administered, and the cancer tissue was absent on subsequent CT and MRI. The cancer was scarred by colonoscopy, and the biopsy showed no malignant cells. Six courses of FOLFIRI plus panitumumab were administered as second-line chemotherapy, and the patient survived without any recurrence after 12 months from initiation of chemotherapy.

[Curative Transanal Resection after Neoadjuvant Chemotherapy for Lower Rectal Cancer-A Case Report].

A 53-year-old woman was referred to our hospital with melena. Examinations revealed advanced rectal cancer involving the anal canal with invasion of the left-sided levator ani muscle. Neoadjuvant chemotherapy was administered to preserve anal function. A first course of capecitabine and oxaliplatin(CapeOX)plus bevacizumab was administered. CapeOX plus panitumumab was administered from the 2nd to the 8th courses after confirming the absence of RAS mutation. Endoscopy and computed tomography confirmed the disappearance of the tumor after completion of the chemotherapy. A biopsy of the scar tissue revealed no cancer cells. However, diffusion weighted-magnetic resonance imaging(MRI-DWI)revealed a suspected residual tumor. To determine the subsequent treatment, a transanal resection was performed. No carcinoma was identified in the specimen. Thus, additional surgical treatment and adjuvant chemotherapy were not administered. The patient was followed-up over 2.5 years post local resection and showed no recurrence.

Histological Comparison of Cold versus Hot Snare Resections of the Colorectal Mucosa.

BACKGROUND: Delayed postpolypectomy bleeding occurs more frequently after hot resection than after cold resection. OBJECTIVE: To elucidate the underlying mechanism, we performed a histological comparison of tissue after cold and hot snare resections. DESIGN: This is a prospective study, registered in the University Hospital Medical Information Network (UMIN000020104). SETTING: This study was conducted at Aizu Medical Center, Fukushima Medical University, Japan. PATIENTS: Fifteen patients scheduled to undergo resection of colorectal cancer were enrolled. INTERVENTION: On the day before surgery, 2 mucosal resections (hot and cold) of normal mucosa were performed on each patient using the same snare without saline injection. The difference was only the application of electrocautery or not. Resection sites were placed close to the cancer to be included in the surgical specimen. MAIN OUTCOME MEASURES: The primary outcome measure was the depth of destruction. Secondary outcome measures included the width of destruction, depth of the remaining submucosa, and number of vessels remaining at the resection sites. The number and diameter of vessels in undamaged submucosa were also evaluated. RESULTS: All cold resections were limited to the shallow submucosa, whereas 60% of hot resections advanced to the deep submucosa and 20% to the muscularis propria (p < 0.001). There was no significant difference in the width of destruction. The number of remaining large vessels after hot resections trended toward fewer (p = 0.15) with a decreased depth of remaining submucosa (p = 0.007). In the deep submucosa, the vessel diameter was larger (p < 0.001) and the number of large vessels was greater (p = 0.018). LIMITATIONS: Histological assessment was not blinded to the 2 reviewers. Normal mucosa was used instead of adenomatous tissue. CONCLUSIONS: Hot resection caused damage to deeper layers involving more large vessels. This may explain the mechanism for the reduced incidence of hemorrhage after cold snare polypectomy. See Video Abstract at http://links.lww.com/DCR/A631.

Accuracy of CT Colonography for Detection of Polypoid and Nonpolypoid Neoplasia by Gastroenterologists and Radiologists: A Nationwide Multicenter Study in Japan.

OBJECTIVES: The objective of this study was to assess prospectively the diagnostic accuracy of computer-assisted computed tomographic colonography (CTC) in the detection of polypoid (pedunculated or sessile) and nonpolypoid neoplasms and compare the accuracy between gastroenterologists and radiologists. METHODS: This nationwide multicenter prospective controlled trial recruited 1,257 participants with average or high risk of colorectal cancer at 14 Japanese institutions. Participants had CTC and colonoscopy on the same day. CTC images were interpreted independently by trained gastroenterologists and radiologists. The main outcome was the accuracy of CTC in the detection of neoplasms ≥6 mm in diameter, with colonoscopy results as the reference standard. Detection sensitivities of polypoid vs. nonpolypoid lesions were also evaluated. RESULTS: Of the 1,257 participants, 1,177 were included in the final analysis: 42 (3.6%) were at average risk of colorectal cancer, 456 (38.7%) were at elevated risk, and 679 (57.7%) had recent positive immunochemical fecal occult blood tests. The overall per-participant sensitivity, specificity, and positive and negative predictive values for neoplasms ≥6 mm in diameter were 0.90, 0.93, 0.83, and 0.96, respectively, among gastroenterologists and 0.86, 0.90, 0.76, and 0.95 among radiologists (P<0.05 for gastroenterologists vs. radiologists). The sensitivity and specificity for neoplasms ≥10 mm in diameter were 0.93 and 0.99 among gastroenterologists and 0.91 and 0.98 among radiologists (not significant for gastroenterologists vs. radiologists). The CTC interpretation time by radiologists was shorter than that by gastroenterologists (9.97 vs. 15.8 min, P<0.05). Sensitivities for pedunculated and sessile lesions exceeded those for flat elevated lesions ≥10 mm in diameter in both groups (gastroenterologists 0.95, 0.92, and 0.68; radiologists: 0.94, 0.87, and 0.61; P<0.05 for polypoid vs. nonpolypoid), although not significant (P>0.05) for gastroenterologists vs. radiologists. CONCLUSIONS: CTC interpretation by gastroenterologists and radiologists was accurate for detection of polypoid neoplasms, but less so for nonpolypoid neoplasms. Gastroenterologists had a higher accuracy in the detection of neoplasms ≥6 mm than did radiologists, although their interpretation time was longer than that of radiologists.

Adverse events during CT colonography for screening, diagnosis and preoperative staging of colorectal cancer: a Japanese national survey.

OBJECTIVES: To retrospectively evaluate the frequencies and magnitudes of adverse events associated with computed tomographic colonography (CTC) for screening, diagnosis and preoperative staging of colorectal cancer. METHODS: A Japanese national survey on CTC was administered by use of an online survey tool in the form of a questionnaire. The questions covered mortality, colorectal perforation, vasovagal reaction, total number of examinations, and examination procedures. The survey data was collated and raw frequencies were determined. Fisher's exact test was used to determine differences in event rates between groups. RESULTS: At 431 institutions, 147,439 CTC examinations were performed. No deaths were reported. Colorectal perforations occurred in 0.014% (21/147,439): 0.003% (1/29,823) in screening, 0.014% (13/91,007) in diagnosis and 0.028% (7/25,330) in preoperative staging. The perforation risk was significantly lower in screening than in preoperative staging CTC procedures (p = 0.028). Eighty-one per cent of perforation cases (17/21) did not require emergency surgery. Vasovagal reaction occurred in 0.081% (120/147,439): 0.111% (33/29,823) in screening, 0.088% (80/91,007) in diagnosis and 0.028% (7/25,330) in preoperative staging. CONCLUSIONS: The risk of colorectal perforation and vasovagal reaction in CTC is low. The frequency of colorectal perforation associated with CTC is least in the screening group and greatest in the preoperative-staging group. KEY POINTS: • The colorectal perforation rate during preoperative-staging CTC was 0.028 %. • The perforation rates for screening and diagnosis were 0.003 % and 0.014 %, respectively. • The perforation risk is significantly lower in screening than in preoperative staging. • Eighty-one per cent of perforation cases did not require emergency surgery. • Use of an automatic colon insufflator can reduce the risk of bowel perforation.

Ultrathin versus pediatric instruments for colonoscopy in older female patients: A randomized trial.

BACKGROUND AND AIM: Small-caliber endoscopes such as gastroscopes or pediatric colonoscopes are occasionally required to negotiate fixed or angulated colons. However, the use of a new ultrathin instrument (diameter 7.0 mm) narrower than other conventional colonoscopes has not been evaluated. The aim of the present study was to compare the use compare the use of an ultrathin colonoscope (UTC) with a pediatric colonoscope (PDC) for colonoscopy in older female patients. METHODS: A prospective, randomized, controlled trial was conducted in a single academic endoscopy unit. A total of 77 female patients aged ≥70 years undergoing unsedated colonoscopy were randomized to colonoscopy with a UTC (n = 39) or PDC (n = 38). Primary outcome measurement was the degree of pain using a numerical rating scale, and secondary outcomes were cecal intubation rate, ileal intubation rate, time to cecum and adenoma detection rate. RESULTS: There was a significant difference in reported pain using the numerical rating scale (median, UTC 1 vs PDC 4, P < 0.0001). Cecal intubation rates were 97.4% in UTC and 92.1% in PDC (P = 0.36), and ileal intubation rates were 82.0% and 89.4% (P = 0.76), respectively. However, median times to cecum were significantly longer using UTC compared with PDC (15.2 min vs 11.1 min, P = 0.022). Adenoma detection rates were 30.7% in UTC and 26.3% in PDC (P = 0.80). CONCLUSIONS: Colonoscopy using UTC was almost equivalent to that of PDC in older female patients, with significantly less pain compared with PDC. UTC may be an alternative to PDC for the difficult colon.

Positive detection of exfoliated colon cancer cells on linear stapler cartridges was associated with depth of tumor invasion and preoperative bowel preparation in colon cancer.

BACKGROUND: The aim of this study was to investigate exfoliated cancer cells (ECCs) on linear stapler cartridges used for anastomotic sites in colon cancer. METHODS: We prospectively analyzed ECCs on linear stapler cartridges used for anastomosis in 100 colon cancer patients who underwent colectomy. Having completed the functional end-to-end anastomosis, the linear stapler cartridges were irrigated with saline, which was collected for cytological examination and cytological diagnoses were made by board-certified pathologists based on Papanicolaou staining. RESULTS: The detection rate of ECCs on the linear stapler cartridges was 20 %. Positive detection of ECCs was significantly associated with depth of tumor invasion (p = 0.012) and preoperative bowel preparation (p = 0.003). There were no marked differences between ECC-positive and ECC-negative groups in terms of the operation methods, tumor location, histopathological classification, and surgical margins. CONCLUSIONS: Since ECCs were identified on the cartridge of the linear stapler used for anastomosis, preoperative mechanical bowel preparation using polyethylene glycol solution and cleansing at anastomotic sites using tumoricidal agents before anastomosis may be necessary to decrease ECCs in advanced colon cancer.

[A Case of Stage IV Colon Cancer Relapsed 10 Years after Curative Resection with Adjuvant Chemotherapy Using Long-Term, Low-Dose Leucovorin and 5-Fluorouracil(LV/5-FU)].

A 57-year-old woman had been diagnosed with sigmoid colon cancer at surgery for ovarian cancer, and underwent simultaneous radical resection. Because of the pathological diagnosis of sigmoid cancer with ovarian metastasis, adjuvant chemotherapy was scheduled, with Leucovorin(LV)25 mg. This was immediately followed with 5-fluorouracil(5-FU)500 mg, via a 2-hour systemic intravenous infusion daily for 5 consecutive days, with courses repeated at 5 weeks, followed by maintenance once every 1 or 2 weeks for 2 years. There had been no evidence of recurrence for 10 years after surgery; however, peritoneal recurrence and a thyroid tumor were found using computed tomography(CT)at the 10-yearsur veillance. Chemotherapy with mFOLFOX6+bevacizumab was initiated because the peritoneal recurrence was determined to be unresectable and because of the metastasis to the thyroid. Chemotherapy was maintained, except for oxaliplatin(L-OHP)due to toxicity, with shrinkage of the peritoneal tumor; however, it was difficult to maintain the chemotherapy due to toxicity. Eleven months after initiation of chemotherapy, lung and bone metastases were detected, and she subsequently died.

Malignant peritoneal mesothelioma with lymph node metastasis that originated in the transverse colon.

BACKGROUND: We report an extremely rare case of resection of localized biphasic malignant peritoneal mesothelioma of the transverse colon. CASE REPORT: Computed tomography and magnetic resonance imaging in a 72-year-old man showed a tumor with enhanced borders consistent with the transverse colon. Colonoscopy showed ulcerative lesions in the transverse colon, but histological examination showed no malignancy. A gastrointestinal stromal tumor was strongly suspected, so an extended right hemicolectomy was performed. Histopathological examination showed that the tumor was a localized malignant peritoneal mesothelioma of the transverse colon. The patient did not receive postoperative chemotherapy and died 18 months after surgery. CONCLUSIONS: The number of patients with malignant mesotheliomas is predicted to increase in the future both in Japan and in western countries. We report this case due to its probable usefulness in future studies pertaining to the diagnosis and treatment of malignant mesotheliomas.

[A case of severe enteritis induced by adjuvant chemotherapy for colon cancer].

A 77-year-old man underwent surgery for sigmoid colon cancer. He was diagnosed with Stage IIIa colon cancer; there- fore, we initiated oral administration of adjuvant chemotherapy comprising uracil/tegafur(UFT)plus Leucovorin(LV). However, chemotherapy was stopped after 21 days because of fatigue and diarrhea. He recovered after 3 weeks, and we administered the same regimen with a dose reduction. However, he again experienced fatigue and diarrhea after 20 days; therefore, chemotherapy was discontinued. Subsequently, he was hospitalized 8 times for conditions such as diarrhea, hypoalbuminemia, and fever. Computed tomography revealed thickening of the transverse colonic wall and colonoscopy revealed colitis, which we believe was induced by UFT plus LV. Twelve months after the last chemotherapy session, he was diagnosed with Clostridium difficile colitis. Therefore, we initiated the oral administration of vancomycin, which resulted in rapid recovery from colitis. However, he developed liver metastasis and died 29 months after the initiation of chemotherapy. We believe that this severe case of intractable colitis was caused by UFT plus LV. Therefore, we report this case with a review of the literature on enteritis induced by fluorouracil-based anticancer agents in Japan.

Acceptance and Preference of Computed Tomographic Colonography and Colonoscopy: Results of a Nationwide Multicenter Comparative Questionnaire Survey in Japan.

Objectives: To investigate patient acceptance and preference for computed tomographic colonography (CTC) over colonoscopy. Methods: Participants were recruited from a nationwide multicenter trial in Japan to assess the accuracy of CTC detection. They were scheduled to undergo colonoscopy after CTC with common bowel preparation on the same day. Some were administered sedative drugs during colonoscopy, depending on the referring clinician and participant's preferences. The participants were requested to complete a questionnaire to evaluate the acceptability of bowel preparation, examinations, and preference for future examinations. Results: Of the 1,257 enrolled participants, 1,180 (mean age: 60.6 years; women: 43.3%) completed the questionnaire. Sedative drugs were not administered in 687 participants (unsedated colonoscopy group) and were administered intravenously during colonoscopy in 493 participants (sedated colonoscopy group). Before propensity score matching, the mean participants' age, percentages of asymptomatic participants, insufflation of gas during colonoscopy, and number of participants with a history of abdominal/pelvic operation significantly differed between the groups. After propensity score matching, 912 participants from each group were included in the analysis. In the unsedated colonoscopy group, CTC was answered as significantly easier than colonoscopy (p<0.001). Conversely, CTC was significantly more difficult than colonoscopy in the sedated colonoscopy group (p<0.001). In the unsedated colonoscopy group, 48% preferred CTC and 22% preferred colonoscopy for future examinations, whereas in the sedated colonoscopy group, 26% preferred CTC and 38% preferred colonoscopy (p<0.001). Conclusions: CTC has superior participant acceptability compared with unsedated colonoscopy. However, our study did not observe the advantages of CTC acceptance over sedative colonoscopy.

Risk Factors and Predictive Biomarkers for Anastomotic Leakage after Colorectal Cancer Surgery with the Double Stapling Technique.

Objectives: Anastomotic leakage (AL) is a serious complication associated with morbidity, mortality, and poor prognosis. This study aimed to identify the risk factors and predictive biomarkers for AL after colorectal surgery with double stapling technique (DST) anastomosis. Methods: We retrospectively analyzed 331 patients who underwent elective colorectal cancer surgery with DST anastomosis between April 2012 and July 2021. Patient-, tumor-, and surgery-related variables were examined using univariate and multivariate analyses to identify the risk factors for AL. Postoperative inflammatory biomarkers were also analyzed to identify the predictive factors for AL. Results: AL occurred in 28 (8.5%) patients. In multivariate analysis, male sex, a history of diabetes mellitus and high ligation of inferior mesenteric artery (IMA) were significant risk factors for AL. Serum C-reactive protein (CRP) levels on postoperative day (POD) 3 and 7 were significantly correlated with AL (OR; 95% CI, 1.134; 1.044-1.232, p = 0.003, and 1.154; 1.036-1.286, p = 0.009, respectively). The cut-off value of CRP on POD 3 was 10.91 mg/dL (sensitivity 0.714, specificity 0.835, positive predictive value [PPV] 0.290, and negative predictive value [NPV] 0.969). The cut-off value of CRP on POD 7 was 4.58 mg/dL (sensitivity 0.821, specificity 0.872, PPV 0.377, and NPV 0.981). Conclusions: Male sex, a history of diabetes mellitus and high ligation of IMA were risk factors for AL in colorectal cancer surgery with DST anastomosis. The predictive biomarkers for cases without AL were CRP levels on POD 3 and 7.

Short-term outcomes of patients undergoing endoscopic submucosal dissection for colorectal lesions.

Objectives: Endoscopic submucosal dissection (ESD) of colorectal lesions was invented in Japan, but postoperative management including hospital stay has not been reconsidered due to the Japanese insurance system. To explore appropriate postoperative management after colorectal ESD, we reviewed short-term outcomes after ESD in non-selected consecutive patients. Methods: Patients who underwent colorectal ESD from April 2013 to September 2020 in one institution were reviewed. The primary outcome measure was the occurrence of adverse events stratified by the Clavien-Dindo classification with five grades. A logistic regression model with the Firth procedure was applied to investigate predictors of severe (grade III or greater) adverse events. Results: A total of 330 patients (female 40%, male 60%; median 72 years; IQR 65-80 years) with colorectal lesions (median 30 mm, IQR 23-40 mm; colon 77%, rectum 23%; serrated lesion 4%, adenoma 47%, mucosal cancer 30%, invasive cancer 18%) was evaluated. The en bloc resection rate was 97%. The median dissection time was 58 min (IQR: 38-86). Intraprocedural perforation occurred in 3%, all successfully treated by endoscopic clipping. No delayed perforations occurred. Postprocedural bleeding occurred in 3% on days 1-10 (median day 2); all were controlled endoscopically. Severe adverse events included only delayed bleeding. In analyzing severe adverse events in a multivariate logistic regression model with the Firth procedure, antithrombotic agent use (p = 0.016) and rectal lesions (p = 0.0010) were both significant predictors. Conclusions: No serious adverse events occurred in this series. Four days of hospitalization may be too long for the majority of patients after ESD.