Colorectal Neuroendocrine Neoplasm Detection Rate During Colonoscopy: Results From Large-Scale Data of Colonoscopies in Japan.

INTRODUCTION: This study investigated the detection rate of colorectal neuroendocrine neoplasms (NENs) using large-scale colonoscopy data. METHODS: This cross-sectional analysis used large-scale data from a Japanese multicenter observational study of colonoscopies performed from 2010 to 2020. RESULTS: Among 82,005 colonoscopy cases, colorectal NENs were identified in 71 (67 of which were neuroendocrine tumors), with a detection rate of 0.087% (95% confidence interval: 0.069-0.109). Most were small rectal lesions, with only 4 >10 mm in size and 3 located in the colon. DISCUSSION: The detection rate of colorectal NENs during colonoscopy is substantially higher than expected.

On the origin of gastric tumours: analysis of a case with intramucosal gastric carcinoma and oxyntic gland adenoma.

Most gastric cancers develop in inflamed gastric mucosa due to Helicobacter pylori infection, typically with metaplastic changes. However, the origins of gastric cancer remain unknown. Here, we present a case of intramucosal gastric carcinoma (IGC) and oxyntic gland adenoma (OGA) derived from spasmolytic polypeptide-expressing metaplasia (SPEM). Early gastric cancer adjacent to a polyp was found in the upper corpus of a 71-year-old woman without H. pylori infection and was endoscopically resected. Histological examination showed IGC and OGA, both of which had predominant MUC6 expression. Interestingly, gastric glands with enriched MUC6-positive mucous cells, referred to as SPEM, expanded between them. Whole-exome sequencing analysis revealed a truncating KRAS(G12D) mutation in IGC, OGA, and SPEM. In addition, TP53 and CDKN2A mutations and a loss of chromosome 17p were found in the IGC, whereas a GNAS mutation was observed in the OGA. These results indicated that IGC and OGA originated from the KRAS-mutated SPEM. © 2023 The Pathological Society of Great Britain and Ireland.

Radiographical consolidation tumor size and preoperative clinical characteristics are significantly correlated with the postoperative survival of patients with part-solid and pure-solid adenocarcinomas: a propensity score-matched analysis.

PURPOSE: Patients with part-solid adenocarcinomas treated by surgery generally have more favorable outcomes than those with pure-solid adenocarcinomas. We conducted this study to understand the effects of the lepidic components and preoperative characteristics on the postoperative survival of patients with part-solid adenocarcinomas. METHODS: The subjects of this retrospective study were 313 patients with stage 1 part-solid adenocarcinomas and 634 patients with pure-solid adenocarcinomas, treated at our institution between 2006 and 2020. Propensity score matching was performed to analyze survival in an unmatched cohort (PSM0, n = 313 vs. 634); a matched cohort based on the consolidation diameter (PSM1, n = 217 each); and a matched cohort based on 11 clinical characteristics (PSM2, n = 103 each). Multivariate analysis was also performed.  RESULTS: The 5-year overall/recurrence-free survival rates for part-solid and pure-solid adenocarcinomas were 90.2%/79.3% and 80.8%/66.0% in the PSM0 cohort (P < 0.0001), 87.4%/79.2% and 76.3%/68.6% in the PSM1 cohort (P < 0.05), and 91.6%/92.1% and 76.6%/79.0% in the PSM2 cohort (P > 0.05), respectively. Multivariate analysis revealed that male sex (P = 0.04) and the carcinoembryonic antigen value (P < 0.0001) were significant factors affecting overall survival, while the carcinoembryonic antigen value (P = 0.0002) and consolidation tumor size (P = 0.002) affected recurrence-free survival. The lepidic component was not related to overall (P = 0.45) or recurrence-free (P = 0.78) survival. CONCLUSIONS: Preoperative factors are strongly associated with "consolidation size", which could be the "representative factor" indicating the malignant potential in adenocarcinomas being consistent with the current eighth edition of the TNM.

Endoscopist-related factors affecting adenoma detection during colonoscopy: Data from the J-SCOUT study.

OBJECTIVES: Colonoscopy withdrawal times are associated with the adenoma detection rate (ADR). However, the relationship between ADR and cecal insertion time has been inadequately characterized. We aimed to evaluate endoscopist-related factors involved in the ADR, including the average individual colonoscopy insertion and withdrawal times. METHODS: This observational study used a colonoscopy database with pathology data from routine clinical practice in Japanese institutions. The odds ratios (OR) of endoscopist-related factors related to ADRs were examined using a generalized linear mixed model. RESULTS: Of the 186,293 colonoscopies performed during the study period, 47,705 colonoscopies by 189 endoscopists in four hospitals were analyzed for ADR. The overall ADR was 38.3% (95% confidence interval [CI] 37.8, 38.7). Compared to endoscopists with mean cecal insertion times of <5 min, the OR of ADR for those with mean cecal insertion times of 5-9, 10-14, and ≥15 min were 0.84 (95% CI 0.71, 0.99), 0.68 (95% CI 0.52, 0.90), and 0.45 (95% CI 0.25, 0.78), respectively. Compared to endoscopists with mean withdrawal times of <6 min, the OR of ADR for those with mean withdrawal times of 6-9, 10-14, and ≥15 min were 1.38 (95% CI 1.03, 1.85), 1.48 (95% CI 1.09, 2.02), and 1.68 (95% CI 1.04, 2.61), respectively. There were no significant differences in ADRs by endoscopist specialty, gender, or the total number of examinations performed. CONCLUSION: Individual mean colonoscopy insertion time was associated with ADR and might be considered as a colonoscopy quality indicator as well as withdrawal time.

The surgical Apgar score predicts postoperative complications and the survival in lung cancer patients.

PURPOSE: The surgical Apgar score (SAS)-calculated using the intraoperative variables estimated blood loss, lowest heart rate, and lowest mean systolic pressure-is associated with mortality in cancer surgery. We investigated the utility of the SAS in patients with lung cancer undergoing surgery. METHODS: We retrospectively analyzed the data of 691 patients who underwent surgery for primary lung cancer between 2015 and 2019 in a single institute and analyzed the impact of the SAS. RESULTS: Of the 691 patients, 138 (20%), 57 (8.2%), and 7 (1.0%) had postoperative complications of all grades, grades ≥ III, and grade V, respectively, according to the Clavien-Dindo classification. The C-index for postoperative complications of grades ≥ III was 0.605. A lower score (0-5 points) (odds ratio 3.09 against 8-10 points, P = 0.04) and a lower percentage of vital capacity (odds ratio 0.97, P = 0.04) were independent negative risk factors for major postoperative complications. Patients with a lower score (0-5 points) had poor 5-year overall and cancer-specific survival rates (60.1% and 72.3%, respectively; P < 0.05 for both). CONCLUSIONS: The surgical Apgar score predicted postoperative complications and the long-term survival. Surgeons may improve surgical results using the SAS.

"Endoscopic" adenoma detection rate as a quality indicator of colonoscopy: First report from the J-SCOUT study.

OBJECTIVES: To examine whether reasonable detection rate of endoscopically diagnosed lesions as adenoma ("endoscopic" adenoma detection rate [ADR]) could be calculated with a database generated from colonoscopy reports and whether it could be used as a surrogate colonoscopy quality indicator of "pathological" ADR. METHODS: A lesion-by-lesion database of colonoscopies performed between 2010 and 2020 at eight Japanese endoscopy centers and corresponding pathology database were integrated. Differences in numbers of detected polyps, "endoscopic" and "pathological" adenomas, and what these differences could be attributed to were examined. Polyp detection rate (PDR), "endoscopic" and "pathological" ADRs, and correlation coefficients between "pathological" ADR and PDR or "endoscopic" ADR by each endoscopist were calculated. RESULTS: Overall, 129,065 colonoscopy reports were analyzed. Among a total of 146,854 polyps, more "endoscopic" adenomas (n = 117,359) were observed than "pathological" adenomas (n = 70,076), primarily because adenomas were not resected on site, rather than because of a misdiagnosis. In all patients analyzed, PDR, "endoscopic" and "pathological" ADRs were 56.4% (95% confidence interval [CI] 56.2-56.7), 48.0% (95% CI 47.7-48.3), and 32.7% (95% CI 32.5-33.0), respectively. "Endoscopic" and "pathological" ADRs from each endoscopist showed a high correlation in hospitals where adenomas were usually resected at the time of examination. CONCLUSIONS: By appropriately describing endoscopically diagnosed lesions as "adenomas" in endoscopy reports, "endoscopic" ADR might be used as a surrogate colonoscopy quality indicator of "pathological" ADR (UMIN000040690).

[Multiple Metastatic Lung Tumors in the Left Upper Lobe Complicated with Hypoplasia and Chronic Atelectasis of the Left Lower Lobe:Report of a Case].

An 80-year-old man with surgical history of colon cancer was referred to our department for surgical treatment for multiple metastatic lung tumors in the left upper lobe. The patient had been showing complete atelectasis of the left lower lung lobe one year prior to the consultation. Six months after wedge resections for the pulmonary metastases, the left lower lobe was re-expanded, showing bronchiectasis with rudimentary pulmonary artery branches. Further, the ventilation-perfusion scintigraphy showed decreased uptake in the left lower lobe. These findings indicated that the patient had the hypoplasia of the left lower lobe.

[Giant Bullae Misdiagnosed as Pneumothorax:Report of a Case].

A 46-year-old man was taken to a hospital by ambulance because of sudden onset of dyspnea, and was inserted chest drainage tube with a diagnosis of right-sided tension pneumothorax on chest X-ray. Since the chest drainage was not effective, he was transferred to our institute. Based on chest computed tomography (CT) findings, a diagnosis of giant bullae of the right lung was made, and surgical treatment was performed. Postoperatively, the improvement of respiratory function was confirmed.

[Radiofrequency Ablation for Pulmonary Metastasis of Ovarian Cancer Caused Iatrogenic Pneumothorax, Leading to Empyema].

A female patient in her 40s who underwent surgery for recurrent right lung metastasis from resected ovarian cancer was referred to our department because of the right pneumothorax due to radiofrequency ablation for multiple lung metastases. Methicillin-resistant Staphylococcus epidermidis( MRSE) was detected from the tip of the drainage catheter indicated persistent pulmonary fistula with right empyema, and surgical treatment was performed. A white coat of the whole lung surface and air leakage were observed at radiofrequency ablation (RFA) treated lesion and partial resection of the right lung, debridement, and irrigation were performed. A pathological examination revealed residual viable ovarian cancer cells and pleural fistula.

Gastric Hyperplastic Polyps Can Shrink After Discontinuation of Proton Pump Inhibitors: A Case Series Compared With Continuation of Proton Pump Inhibitors.

GOAL: This study investigated whether gastric hyperplastic polyps (GHPs) shrink after discontinuation of proton pump inhibitor (PPI) alone. BACKGROUND: Long-term use of PPIs has been reported to increase the incidence of GHPs, which sometimes bleed and cause anemia. We experienced a patient whose recurrent hemorrhagic GHPs associated with long-term use of PPIs had disappeared after discontinuation of PPIs. STUDY: This study was conducted retrospectively at Kyoto University Hospital. Patients with histologically confirmed GHPs who had been taking PPIs for >6 months and who had undergone a repeat endoscopy within 2 years were included. Polyp shrinkage was defined as the disappearance of polyps or a reduction of >50% in the long diameter of the largest polyp. RESULTS: Six patients who discontinued PPIs were compared with 17 patients who continued PPIs. Polyp shrinkage was significantly more frequent in the PPI-discontinuation group (5/6, 83%) than in the PPI continuation group (0/17, 0%) (P<0.001). In 2 patients in the PPI-discontinuation group, the polyps completely disappeared finally. CONCLUSION: These findings suggest that discontinuation of PPIs can shrink GHPs in patients using PPIs.

Thermal tissue damage caused by new endoscope model due to light absorption.

BACKGROUND AND AIM: Bright endoscopic light sources improve the visibility of the intestinal mucosa. A newly launched endoscopic system developed by Olympus Corporation (Tokyo, Japan) in 2020 required modification to prevent heat-induced tissue damage, which reportedly occurs during magnifying chromoendoscopy. We investigated the mechanism of this phenomenon by evaluating the rise in temperature of stained and unstained porcine mucosa using the new and previous endoscopic systems. METHODS: Surface temperatures of stained (India ink, 0.05% crystal violet, 0.5% methylene blue, or 0.2% indigo carmine) and unstained porcine mucosa were evaluated using infrared imaging after contact with the new endoscopic system before it was modified (system-EVIS X1; scope-GIF-EZ1500) and compared with a previous endoscopic system (system-EVIS EXERAIII; scope-GIF-H190). We performed histological analysis of the porcine mucosa stained with 0.05% crystal violet after contact with the new endoscope to evaluate the degree of tissue damage. RESULTS: Surface temperatures remained < 40°C when the new endoscope was in contact with the unstained mucosa. However, the maximum surface temperature rose to > 70°C when the new endoscope was in contact with the stained mucosa (stained other than indigo carmine). Histological analysis revealed cavity formation in porcine epithelium stained with crystal violet where the endoscope made contact for ≥ 5 s . Using the previous endoscope, the maximum surface temperature of stained mucosa remained below approximately 60°C, and the surface temperature of the unstained mucosa remained below 30°C. CONCLUSIONS: Heat transfer by light absorption could cause heat-induced tissue damage during magnifying chromoendoscopy using the new endoscope.

Factors associated with inaccurate size estimation of colorectal polyps: A multicenter cross-sectional study.

BACKGROUND AND AIM: Accurate polyp size estimation is essential in deciding the therapeutic strategy of colorectal polyps and endoscopic surveillance intervals. However, many endoscopists frequently make incorrect size estimations without being aware of their errors. This cross-sectional study aimed to clarify the characteristics of endoscopists associated with inaccurate estimation. METHODS: We previously conducted a web trial involving 261 endoscopists in 51 institutions in Japan to assess their ability to estimate polyp size. Participants answered questions about polyp size using visual estimates in a test involving images of 30 polyps. Here, we investigated the relationships between inaccurate size estimation and the backgrounds of participants. The rates of overestimation and underestimation of polyp size were also compared to clarify any trends in the answers of participants with low accuracy (< 50%). RESULTS: Multivariable logistic regression analysis revealed that the number of colonoscopic procedures in the past year was the only factor associated with a low accuracy of polyp size estimation (odds ratio 0.750, 95% confidence interval 0.609-0.925; P = 0.007). Endoscopists with low accuracy had a greater tendency to overestimate polyp size (42.3% overestimation and 21.2% underestimation, P < 0.001) compared with other endoscopists (16.6% overestimation and 17.9% underestimation, P = 0.951). CONCLUSIONS: Endoscopists with limited experience of colonoscopy in the past year were more likely to make frequent errors in size estimation. Furthermore, endoscopists making inaccurate size estimations had a propensity to overestimate polyp size.

Spontaneous regression of mismatch repair-deficient colorectal cancers: Case series.

Spontaneous regression (SR) has been reported in various malignant tumors. However, SR in colorectal cancer (CRC) is particularly rare and the mechanism remains unclear. We here report three cases of CRCs displaying SR, which were experienced at two institutions. Intriguingly, all of these cases displayed the common endoscopic characteristics; superficial elevated lesion accompanied by a central depression (0-IIa + IIc, in the Paris classification), with a nonpolypoid growth, located in the ascending colon. Furthermore, immunohistology of biopsy specimens revealed the lack of DNA mismatch repair proteins within the CRC lesions, suggesting that these were mismatch repair-deficient (dMMR) CRCs. One of the major features of dMMR cancers is an increase in the number of tumor-infiltrating lymphocytes. Thus, the dMMR phenotype might be associated with SR of CRCs through the activation of anti-tumor host immune responses.

[Pulmonary Nontuberculous Mycobacteriosis Difficult to Differentiate from Local Recurrence of the Metastatic Lung Tumor of the Uterine Cervix Cancer at the Staple-line:Report of a Case].

A 70-year-old woman underwent right S6 segmentectomy and left S6 partial resection for lung metastasis of uterine cervix cancer. Although she received adjuvant chemotherapy, chest computed tomography revealed a new pulmonary nodule on the staple stump of the right lung. We diagnosed the tumor as local recurrence at the stump and planned to continue chemotherapy. However, the size of the tumor increased, and we performed right middle and lower lobectomy. Based on the pathological and bacteriological examinations, an epithelioid cell granuloma infected by Mycobacterium avium was established.

Clinical importance of cold polypectomy during the insertion phase in the left side of the colon and rectum: a multicenter randomized controlled trial (PRESECT study).

BACKGROUND AND AIMS: Colorectal polyps are often detected during the insertion phase of colonoscopy but are commonly removed during the withdrawal phase. We aimed to investigate the clinical advantages of instant removal of colorectal polyps during the insertion phase to determine the appropriate strategy for polyps detected on insertion. METHODS: This prospective, multicenter, randomized trial targeted patients with at least 1 left-sided polyp <10 mm in size detected unintentionally on endoscope insertion from April 2018 to March 2019. Patients were allocated to the following 2 groups: study group, consisting of patients who had polyp removal instantly on insertion, and control group, comprising patients who had the endoscope inserted to the cecum first and polyps removed subsequently on withdrawal. Carbon dioxide gas insufflation and cold polypectomy were applied to minimize the influences of polypectomy on endoscope insertion. Twenty advanced endoscopists from 7 community-based institutions participated in this trial. RESULTS: Of 1451 patients enrolled, 220 patients were eligible for full assessment. Mean total procedure time was significantly shorter in the study group (18.9 vs 22.3 minutes, P < .001). Mean pure cecal intubation time and number of polyps per patient were similar between the 2 groups. In the control group, among 107 polyps found during insertion, 48 (45.8%) required reinspection and 7 (6.5%) were completely missed, with an average reinspection time of approximately 3 minutes. CONCLUSIONS: Polypectomy during the insertion phase in the colon and rectum significantly shortens the total procedure time and eliminates all missed polyps without experiencing any disadvantages.

Short educational video to improve the accuracy of colorectal polyp size estimation: Multicenter prospective study.

BACKGROUND AND AIM: Accurate polyp size estimation is necessary for appropriate management of colorectal polyps. Polyp size is often determined by subjective visual estimation in clinical situations; however, it is inaccurate, especially for beginner endoscopists. We aimed to clarify the usefulness of our short training video, available on the Internet, for accurate polyp size estimation. METHODS: We conducted a multicenter prospective controlled study in Japan. After completing a pretest composed of near and far images of 30 polyps, participants received the educational video lecture (<10 min long). The educational content included the knowledge of strategies based on polyp size and criteria for size estimation including the endoscopic equipment size and videos of polyps in vivo. After one month, the participants undertook a posttest. The primary outcome was a change in the accuracy of polyp size visual estimation between the pretest and posttest in beginners. RESULTS: Participants including 111 beginners, 52 intermediates, and 97 experts from 51 institutions completed both tests. Accuracy of polyp size estimation in the beginners showed a significant increase after the video lecture [54.1% (51.3-57.0%) to 59.0% (56.5-61.5%), P = 0.003]. Multivariable logistic regression analysis showed that the category of beginners and a low score on pretest (P = 0.020 and <0.001, respectively) were the factors that contributed to an increase of ≥10% in the accuracy. CONCLUSION: Our educational video led to an improvement in polyp size estimation in beginners. Furthermore, this video may be useful for non-beginners with insufficient polyp size estimation accuracy.

[Pulmonary Benign Metastasizing Leiomyoma Found as Multiple Bilateral Lung Nodules 11 Years after Hysterectomy;Report of a Case].

Pulmonary benign metastasizing leiomyoma (PBML) is a rare entity. We herein report a case of PBML found as multiple bilateral lung nodules 11 years after total hysterectomy. The patient was a 53-year-old woman with past surgical history of abdominal total hysterectomy for a uterine leiomyoma at the age of 42. She was referred to our department for further evaluation of multiple pulmonary nodules detected by a chest radiography. A chest computed tomography revealed multiple bilateral small lung nodules less than 10 mm in diameter. 18-fluorodeoxyglucose (FDG) positron emission tomography showed no significant FDG accumulation to these nodules. The patient finally underwent video assisted thoracoscopic wedge resection of the lower lobe of the right lung for surgical biopsy. The final pathological diagnosis was PBML, based on the comparative evaluation of the surgical specimens from the lung and the uterus. No evidence of enlargement in the remaining pulmonary nodules was noted for 9 months after surgical lung biopsy.

Standards of diagnostic colonoscopy for early-stage neoplasia: Recommendations by an Asian private group.

BACKGROUND AND AIM: In recent years, the incidence of colorectal cancer has been increasing, and it is now becoming the major cause of cancer death in Asian countries. The aim of the present study was to develop Asian expert-based consensus to standardize the preparation, detection and characterization for the diagnosis of early-stage colorectal neoplasia. METHODS: A professional group was formed by 36 experts of the Asian Novel Bio-Imaging and Intervention Group (ANBI2 G) members. Representatives from 12 Asia-Pacific countries participated in the meeting. The group organized three consensus meetings focusing on diagnostic endoscopy for gastrointestinal neoplasia. The Delphi method was used to develop the consensus statements. RESULTS: Through the three consensus meetings with debating, reviewing the literature and regional data, a consensus was reached at third meeting in 2016. The consensus was reached on a total of 10 statements. Summary of statements is as follows: (i) Adequate bowel preparation for high-quality colonoscopy; (ii) Antispasmodic agents for lesion detection; (iii) Image-enhanced endoscopy (IEE) for polyp detection; (iv) Adenoma detection rate for quality indicators; (v) Good documentation of colonoscopy findings; (vi) Complication rates; (vii) Cecal intubation rate; (viii) Cap-assisted colonoscopy (CAC) for polyp detection; (ix) Macroscopic classification using indigocarmine spray for characterization of colorectal lesions; and (x) IEE and/or magnifying endoscopy for prediction of histology. CONCLUSION: This consensus provides guidance for carrying out endoscopic diagnosis and characterization for early-stage colorectal neoplasia based on the evidence. This will enhance the quality of endoscopic diagnosis and improve detection of early-stage colorectal neoplasia.