Toward an easier indigocarmine chromoendoscopy

Indigocarmine chromoendoscopy has been proven to improve the detection of colonic lesions during screening colonoscopy, and is associated with increased adenoma detection rates. Furthermore, it is commonly used to help in the delineation and characterization of colorectal neoplasms. However, it usually requires the use of a spraying catheter that decreases the suction capacity of the endoscope, and is time- consuming. Herein, we report on the feasibility of indigo carmine chromoendoscopy during colonoscopy without using a spraying catheter, with the dye being administered through the air/water channel of the endoscope. Since the suction channel remains free, the air can be exsufflated and the staining then applies uniformly onto the colonic walls with the excess indigocarmine dye being immediately eliminated. In our experience with various types of colonoscopes and cap-assisted colonoscopy, this procedure makes indigocarmine chromoendoscopy much easier and quicker to perform, and might save the use of a spray catheter.     

Reduction of miss rates of colonic adenomas by zoom chromoendoscopy

Background and aims The aim of this study was to determine the detection rate of polyps using zoom chromoendoscopy (ZE) compared with standard video colonoscopy.Patients and methods End-to-end colonoscopies were performed in 50 patients by two different endoscopists blinded for each other’s results. Lesions detected during initial standard colonoscopy (C1) were biopsied or removed by snare resection. The second colonoscopy (C2) was done with a zoom colonoscope spraying the whole colon with indigocarmine (0.4%). In addition, detected mucosal lesions were documented prior to ZE and then classified according to the pit pattern classification before biopsy or removal. The retrieval time for each procedure was determined. Results: The average retrieval time for C1 was 13±9 min (9–24) and 28±11 min (16–38, p<0.05) for ZE. During C1, 56 lesions were detected in 26 of 50 patients (34 hyperplastic and 22 adenomatous). During C2, 19 additional polyps were documented prior to ZE (15% tandem miss rate), and 20 further lesions were detected with ZE (21% additional polyp detection rate compared to C1 and C2 without ZE). Of the 39 additional lesions removed during C2 after ZE, 29 were hyperplastic and 10 were adenomatous. Most adenomas detected during the second investigation were found in patients in whom adenomatous polyps had already been removed during the initial colonoscopy (9 of 26 patients vs 1 of 24 patients, p<0.02). No carcinoma was detected. The pit pattern classification allowed a correct differentiation between hyperplastic and adenomatous polyps (accuracy 93%, sensitivity 90%, specificity 97%).Conclusion Using zoom chromoendoscopy, the rate of detecting colonic polyps can be increased at the cost of a longer retrieval time.     

The use of indigocarmine spray increases the colonoscopic detection rate of adenomas

Purpose  It remains controversial whether chromocolonoscopy using indigocarmine increases the detection of colorectal polyps. We aimed to assess the impact of indigocarmine dye spray on the detection rate of adenomas and the feasibility of learning the technique in a Western practice. Methods  400 patients were prospectively allocated into 2 groups; A (n = 200): indigocarmine chromocolonoscopy was performed by a Japanese colonoscopist with expertise in chromoscopy; B (n = 200): initial 100 patients (B-1), a Western colonoscopist with no previous experience of chromoscopy performed conventional colonoscopy, but with at least 10 min observation during colonoscopy withdrawal. In the next 100 patients (B-2), he performed chromocolonoscopy. All polyps found were resected. Regression analysis was used to compare the numbers of polyps detected in groups A, B-1 and B-2, whilst controlling for gender, age, indication and history of colorectal cancer. Results  There were significant differences in the numbers of neoplastic polyps and flat adenomas between groups A and B-1 as well as between B-1 and B-2, but not between A and B-2. There was no significant difference in numbers of advanced lesions. Chromocolonoscopy (A and B-2) detected more neoplastic polyps of ≤5 mm. Conclusion  Chromocolonoscopy increases the detection of neoplastic polyps and flat adenomas, particularly diminutive polyps, but does not increase the detection of advanced lesions.     

Detection of colorectal adenomas using artificial intelligence models in patients with chronic hepatitis C

BACKGROUND Hepatitis C virus is known for its oncogenic potential,especially in hepatocellular carcinoma and non-Hodgkin lymphoma.Several studies have shown that chronic hepatitis C(CHC) has an increased risk of the development of colorectal cancer(CRC).AIM To analyze this positive relationship and develop an artificial intelligence(AI)-based tool using machine learning(ML) algorithms to stratify these patient populations into risk groups for CRC/adenoma detection.METHODS To develop the AI autom...     

Right-side shift of colorectal adenomas with aging

BACKGROUND: Although it is known that right-side colon cancers increase with aging, the location of adenomas according to age has been controversial. Adenomas found at initial colonoscopies may be a mixture of polyps that arose at various earlier ages. OBJECTIVES: To elucidate the relationship between location and age at which adenomas actually developed. DESIGN: Prospective cohort study. SETTING: A large-scale health appraisal institution in Japan. PATIENTS: A total of 23,444 consecutive, asymptomatic Japanese who underwent total colonoscopy at their annual medical health check-up. INTERVENTIONS: We analyzed newly developed adenomas after confirmation of the absence of colorectal neoplasms by two serial total colonoscopies. MAIN OUTCOME MEASUREMENTS: The results of follow-up colonoscopies in 6304 subjects with no colorectal neoplasms at 2 initial colonoscopies were analyzed. The locations were separated into right-side colon and left-side colon from the splenic flexure. The locations of new adenomas found for the first time during the follow-up term were analyzed. RESULTS: A total of 1472 subjects developed new colorectal adenomas. In 1255 cases with single adenomas, the ratios of number of cases with right-side lesions to that with left-side lesions at the ages of <40 years, 40 to 49 years, 50 to 59 years, 60 to 69 years, and > or =70 years were 1.18, 1.00, 1.29, 1.31, and 1.89, respectively. In 217 cases with multiple adenomas found concurrently, the percentage of cases with adenomas only on the right side at the ages of <40 years, 40 to 49 years, 50 to 59 years, 60 to 69 years, and > or =70 years were 0%, 25%, 34%, 37%, and 63%, respectively. LIMITATIONS: Small lesions might have been missed even by 2 serial colonoscopies. CONCLUSIONS: Adenomas on the right-side colon increased with aging.     

Detection of unrecognized liver metastases from colorectal cancers by routine use of operative ultrasonography

The importance of diagnosis and detection of liver metastases cannot be overemphasized for the treatment and prognosis of colorectal cancers. As a new diagnostic technique, operative ultrasonography has been performed during 33 operations for colorectal cancers including three operations for metachronous liver metastases. Of these, in five patients (15.2 percent) ultrasonography using 5- or 7.5-MHz instruments identified metastatic tumors that had not been diagnosed during preoperative imaging studies or at exploration. Most of these tumors were approximately 1 cm in size and nonpalpable. Cases of these five patients are presented in this report. High-resolution operative ultrasonography is considered to be a valuable method for detection of unrecognized metastatic tumors and for precise localization and spatial assessment of these hepatic lesions. Because it is safe, simple, and highly sensitive, the routine use of operative ultrasound is encouraged during surgery upon colorectal cancers for systematic screening of metastatic liver tumors.     

染色放大内镜下大肠黏膜表面微细结构改变及其临床病理意义

目的通过染色放大内镜观察不同大肠黏膜病变的Pitpattern形态,探讨其在早期大肠癌诊断中的应用价值。方法应用染色放大内镜对146例患者的大肠黏膜进行细微结构形态学观察,并与观察部位活检所得的病理组织学改变进行比较分析。结果 146例患者中放大内镜检出息肉172枚,经0.2%的靛胭脂染色放大后又发现0.1～0.5cm大小的息肉84枚,共计息肉样病变256枚。染色放大内镜可明显提高息肉病变的检出率。各种腺管开口分型的病理诊断结果构成差异有显著性,Ⅰ～Ⅴ分型与病变严重程度之间呈明显正相关。染色放大内镜对大肠肿瘤性病变诊断符合率89.5%、敏感性82.2%、特异性92.3%,放大内镜诊断符合率71.5%、敏感性61.8%、特异性77.9%,染色放大内镜对大肠肿瘤性疾病诊断与放大内镜相比差异具有统计学意义（P〈0.01）。结论染色放大内镜对大肠肿瘤的诊断优于放大内镜,能够提高大肠癌的早期诊断率,从而为大肠癌及其癌前病变的内镜下正确处理提供快速而准确的依据。     

Detection of proliferative cells in colorectal carcinomas and adenomas by monoclonal antibody to DNA polymerase alpha

DNA polymerase alpha is an endogenous DNA replication enzyme expressed in all cells in a proliferation cycle. An immunoperoxidase method and the monoclonal antibody to DNA polymerase alpha were used to identify proliferating cells in colorectal carcinomas (n = 35) and adenomas (n = 43). The labeling index (L.I.) in colorectal carcinomas was 51.6%, being significantly higher than 28.6% in adenomas. The L.I. in colorectal carcinomas correlated with clinical staging (stage I: 33.1%, stage II and III: 49.5%, stage IV and V: 66.9%). Furthermore, the L.I. had a tendency to elevate as carcinoma deeply invaded (pm: 25.8%, ss-s or a1-a2: 52.2%, si or ai: 67.5%). The L.I. in adenoma was related to the degree of atypia. The L.I. in adenomas with mild atypia, with moderate atypia, and cancer in adenoma were 18.3%, 31.5%, and 47.0%, respectively. And the L.I. of cancer in adenoma had no significant difference in advanced carcinomas (47.0% vs 51.6%). These results suggest that the L.I. is useful as a marker for evaluating the degree of biological malignancy of human colorectal carcinomas and the degree of histopathological atypia of adenomas.     

Mandibular osteomas in colorectal adenomas

Orthopantomography of the mandible was carried out on 50 patients with colorectal adenoma(s) without carcinoma or any known familial disposition. Four patients (8%) had osteomas, and we advance the hypothesis that individuals with both osteomas and adenomas represent a separate type of adenoma patient. Further studies are needed to evaluate the prognostic value of the association of adenomas and mandibular osteomas.     

Improved detection of colorectal neoplasms with selective use of chromoendoscopy in 2005 consecutive patients

Background Colorectal cancer mortality is decreased by endoscopic polypectomy, but conventional colonoscopy may be inadequate for detecting subtle colonic lesions. Methods We selectively performed chromoendoscopy in all patients undergoing colonoscopy between January 1999 and December 2005 at the International Health Union of Rome. Patients with a history of colorectal polyps, inflammatory bowel disease, colorectal surgery or coagulopathy and those with poor bowel preparation were excluded from this analysis. Whenever colonoscopy revealed suspicious mucosal areas, dye-spraying with 0.2% indigo carmine solution was also performed. Findings from conventional and dyespraying views were classified morphologically, and specimens were analyzed histologically. Non-adenomatous lesions were classified as negative findings. Results A total of 2005 patients underwent conventional colonoscopy and in 305 cases (15%) chromoendoscopy was also performed. Conventional colonoscopy identified 508 neoplasms in 381 patients (19%). Selective chromoendoscopy found an additional 244 neoplasms in 212 patients (11%). Thus, chromoendoscopy was positive in 212 (70%) of 305 patients in whom the examination was performed. Overall, 56 large, ulcerated, advanced cancers and 696 non-advanced neoplasms were found. Of the 696 nonadvanced neoplasms, 448 (65%) were polypoid and 248 (35%) were non-polypoid. All but 4 non-polypoid lesions were only detected with chromoendoscopy. Of the 248 non-polypoid lesions, 12 (5%) were depressed and 236 (95%) were flat. Advanced histology was present in 39 non-polypoid lesions (15%) and was more common in depressed lesions than in flat ones (58% vs. 13%; p<0.001). Conclusions Our study confirms the existence of flat and depressed neoplasms in an Italian population. The vast majority of non-polypoid lesions were only detected by chromoendoscopy, and many lesions with advanced histology were missed by conventional colonoscopy. We therefore recommend selectively performing chromoendoscopy when conventional colonoscopy provides clues for non-polypoid lesions. Therefore, endoscopists should be trained in the detection of these subtle mucosal clues, as well as in the use of chromoendoscopy to enhance their detection. An erratum to this article is available at .     

Androgen receptors in colorectal adenomas

Summary To evaluate the potential effect of androgens on the development and growth of human colorectal adenomas, the prevalence and concentration of cytosolic androgen receptors (AR) were analysed in 26 adenomas and 19 samples of normal colonic mucosa by a hybrid ligand receptor-binding assay. AR were detected in 7 of the adenomas (26.9%), and in 6 of the normal mucosa samples (31.6%). In the adenomas, AR levels demonstrated were low, ranging from 6 to 31 fmol/mg cytosol protein, and dissociation constants (Kds) ranged from 0.17–2.7x10^-9 M. Of 13 adenomas excised from men, 6 (46%) had positive receptor activity, whereas only 1 of 13 (7.7%) from women was positive (P=0.03, Fisher's exact test). There was no correlation between AR titre and patient age, or between adenoma size and histological type or degree of dysplasia. In normal mucosa, AR levels ranged from 7 to 33 fmol/mg and Kds ranges from 0.24–3.1x10^-9 M. There was no significant difference between either AR prevalence or levels in the adenomas and normal mucosa. The sex difference was exclusive to the adenoma. Endogenous androgen may play a role in adenoma development early in the promotional process.     

Squamous differentiation in colorectal adenomas

Patterns of stratified squamous epithelium have been recognized recently in colorectal adenomas. Light microscopic and keratin immunohistochemical analysis of four cases in the present report suggested origin from large intestinal reserve cells, with impaired and disorderly maturation in the squamous foci. One case had an invasive adenocarcinoma separately in the same polyp, bringing the reported incidence of malignant transformation in these adenomas to seven of 48 (15 percent). Evidence is presented to support the notion that squamous differentiation may be an inherently neoplastic phenomenon in colorectal adenomas, which may be added to the list of markers for colorectal polyps at higher risk for malignant transformation.