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.     

内镜下切除结直肠高危腺瘤随访166例

目的:探讨结直肠高危腺瘤内镜下切除后的复发特点.对今后高危腺瘤患者规范筛查和合理随访提出指导.方法:收集2004-01/2009-01发现结直肠高危腺瘤并经内镜下切除的患者详细临床资料.对于腺瘤切除后继续在我院内镜随访的患者进行登记.结果:共收集结直肠高危腺瘤497例患者,其中166例腺瘤切除后继续在我院行内镜随访.随访的166例患者一般资料分布:年龄32-82(平均61.64±11.07)岁,其中年龄≥55岁患者128例(128/166,77.11%),男性94例(94/166,56.63%),高危腺瘤以便血为首发症状的患者较多见(71/166,46.38%),且腺瘤表面易形成分叶(75/166,54.82%).首次复查时间为切除后1-28mo,共102例患者(102/166,61.45%)复发.高危腺瘤切除后的复发部位特点:初发于左半结肠的腺瘤易复发于左半结肠,初发于右半结肠的腺瘤易复发于右半结肠(r=0.440,0.387,均P<0.01),将高危腺瘤切除前后的病理表现进行比较未见明显相关性.Cox模型的风险量曲线图提示随时间的延长,从6mo开始患者息肉复发的风险逐渐增大.结论:结直肠高危腺瘤切除后存在...     

Risk of developing metachronous colorectal neoplasia after the resection of proximal versus distal adenomas

BackgroundCurrent post-polypectomy guidelines do not consider adenoma location. We compared the risk of metachronous colorectal neoplasia (CRN) according to adenoma location.MethodsWe collected data from 9710 patients who underwent follow-up colonoscopy after adenoma removal. Patients were classified according to baseline adenoma location: distal only (n=4665), proximal only (n=3827), and both sides (n=1218).ResultsThe risk of metachronous CRN in patients with proximal only adenomas was higher than that in those with distal only adenomas (adjusted hazard ratio [aHR]=1.12, 95% confidence interval [CI]=1.04–1.21), while the risk of metachronous advanced CRN (ACRN) was not different between the two groups. Among patients aged <50 years, the risk of metachronous CRN in those with proximal only non-advanced adenomas (NAAs) was higher than that in those with only distal NAAs, while among patients aged ≥ 50 years, the risk in those with proximal only advanced adenomas (AAs) was higher than that in those with distal only AAs. However, the risk of metachronous ACRN did not differ based on adenoma location in patients aged < 50 and ≥ 50 years.ConclusionsProximal adenoma was associated with an increased risk of metachronous CRN, but not with an increased risk of metachronous ACRN, supporting the current guidelines recommending the same surveillance interval for distal and proximal adenoma without discrimination by adenoma location.     

Villous component as a marker for synchronous and metachronous colorectal adenomas

To determine whether patients with colorectal adenomas containing a villous component (+vc group) have a higher incidence of synchronous or metachronous colorectal adenomas, 527 consecutive cases of completely removed colorectal adenoma were used. Synchronous adenomas were detected in 22.6 percent and 19.0 percent of the patients in the +vc and –vc groups, respectively. In the analysis of metachronous adenomas, 164 patients who had been followed for 1 to 11 years (mean, 3.31 years) were included. The cumulative adenoma-free rate according to Kaplan-Meier tended to be lower in the +vc group, the difference being statistically significant 1.0 to 1.2 years after treatment of the initial adenoma and the two curves being different based on the generalized Wilcoxon test. The numbers of newly detected adenomas annually were 1.76 and 0.86, and their annual incidences were 1.09 and 0.59 times, in the +vc and –vc groups, respectively. These results suggest the importance of the villous component as a predictor of metachronous colorectal adenomas.     

高频电切术所致大肠壁损伤的组织病理学观察

目的观察大肠壁高频电切术所致的组织学损伤,阐明其组织病理学特征,为临床防治并发症提供有价值的参考资料.方法采用组织病理学方法,观察34例外科切除大肠标本上的47处内镜高频电切术切除部位和内镜切除标本.结果47处内镜切除部位的粘膜下层均有不同程度的病变,28处(59.6%)可见肌层或浆膜层的电热损伤,常表现为内肌层肌组织坏死、内外肌层间出血或纤维化及浆膜损伤.病变大多是局灶性的,与粘膜下层的病变不连续,呈现跳跃式的分布内镜切除标本的深度仅限于粘膜下层以内.内镜切除部位有肌层或浆膜病变者,内镜切除标本的平均最大径大于没有肌层或浆膜病变者(P<0.05).内镜切除标本最大径<10mm时,也可见肌层或浆膜的损伤.结论内镜切除术引起的无症状的肠壁电热损伤并不少见,其出现与内镜切除标本的大小有关,内镜切除最大径<10mm的组织也可导致电热损伤并可能引起肠壁全层坏死.     

结直肠息肉切除后并发出血的研究进展

随着我国经济社会的发展,结直肠癌的发病率和死亡率在我国呈现出逐年上升的趋势,目前是我国发病率第四位的肿瘤。结直肠镜检查及内镜下息肉切除术是降低结直肠癌发病率和死亡率的重要手段]。出血、术后电凝综合征、穿孔和腹部不适是内镜下结直肠息肉切除术的主要并发症,其中以出血最常见。结直肠息肉切除后出血会引起一系列不良事件,包括：病人急诊观察、再次入院、重复内镜检查、内镜下止血、输血、血管造影栓塞甚至外科手术结直肠切除,对医院及患者而言均是较大的负担,本文对结直肠息肉切除后并发出血的研究进展做一综述,重点讨论结肠息肉切除后出血的流行病学、出血相关危险因素、出血后处置方法及预防出血措施,以期加深临床医师对此种并发症的认识,从而更好的指导临床工作。     

Follow-up after colorectal polypectomy. II. Repeated examinations of the colon every 6 months after removal of sessile adenomas and adenomas with the highest degrees of dysplasia

Fifty-five patients with colorectal sessile adenomas and adenomas with the severest dysplasia were followed up every 6 months with colonoscopy and/or double-contrast enema during 4 years, after a clean colon had been obtained, by repeated colonoscopy within 3 months after piecemeal polypectomy. The repetition at 3 months resulted in detection of two cancers. An overlooked cancer was detected at 1 year, and another cancer was diagnosed between examinations. Risk of new adenomas (19 patients) was related to original size, number, and glandular structure of the polyps. Twelve of the 19 patients had new polyps above the rectum. The 336 colonoscopies were complicated by 3 laparotomies, made necessary by perforation and bleeding. The results suggest that intervals between examinations of patients with the present type of adenomas may be prolonged, and patients are now allocated at random to colorectal follow-up examination every 6 and 12 months.     

Risk of metachronous neoplasia on surveillance colonoscopy among young and older patients after polypectomy

Background and aimsFew reports address the appropriate colonoscopy surveillance interval for individuals <50-years-old. We compared the risk of metachronous neoplasia among young (<50 years), adult (50–74 years) and older (≥75 y) age groups.MethodsThis was a single center retrospective cohort study. Eligible subjects underwent their first colonoscopy with polypectomy between 2005 and 2014 and had at least one surveillance colonoscopy 3–5 years later. Patients (N = 495) were stratified at baseline into low-risk adenoma (LRA) and advanced adenoma groups. Study outcomes were overall and high-risk neoplasia at surveillance colonoscopy.ResultsIn the baseline LRA-group (N = 201), the 5-year risk of metachronous high-risk neoplasia was 12.5%, 15.2% and 22.5% (P = 0.426) in the young, adult and older age groups, respectively. In the baseline advanced adenoma group (N = 294), the 3-year risk of metachronous high-risk neoplasia was 13.3%, 14.8% and 25.3% (P = 0.041), respectively. In multivariate analysis, the only risk factor for metachronous high-risk neoplasia was older age (OR 1.876, CI 1.087–3.238; P = 0.024).ConclusionsConsidering the comparable risk of metachronous high-risk neoplasia in young and adult patients, surveillance recommendations after polypectomy should not differ. Since this risk is higher among older people, more frequent surveillance schedule can be considered for this age group but should be individualized.     

Patterns of metachronous adenoma after colorectal cancer surgery]

BACKGROUND/AIMS: After colorectal cancer surgery, colonoscopic surveillance should be done for prevention and early detection of secondary cancer. This study aimed to identify the group with high risk of developing colorectal adenoma after curative surgery of colorectal cancer. METHODS: We retrospectively investigated the medical records of the subjects of 130 patients who had been examined using colonoscopy before and after the curative surgery. RESULTS: The average age was 59.4 years. Synchronous adenomas were in 42 patients (32.3%). The occurrence rate was significantly high in men (38.8%) than women (22.0%). After the operation, the mean interval of examining colonoscopy was 11.6 months (3-24 months) and metachronous adenomas were detected in 26 patients (20.0%). The patients who have both metachronous and synchronous adenomas were observed in 13/42 (30.9%) and the patients of metachronous adenomas without synchronous adenomas were observed in 13/88 (14.8%). The occurrence rate of metachronous adenomas with synchronous adenomas was significantly high. The frequency of synchronous adenomas didn't increase with age. However, the frequency of metachronous adenomas increased with age: 0/9 (0%) under 40 years, 7/49 (14.3%) in 41-61 years and 19/72 (26.4%) over 61 years. The occurrence rate was higher in men (26.3%) than women (10.0%). CONCLUSIONS: The occurrence rate of metachronous adenomas after colorectal cancer surgery was higher in the patients with synchronous adenomas, male gender and old aged patients.     

Risk and cause of interval colorectal cancer after colonoscopic polypectomy

Background: To investigate the cause and risk of interval colorectal cancer (ICC) in patients undergoing surveillance colonoscopy within 5 years after colonoscopic polypectomy. Patients and Methods: We retrospectively analyzed data (endoscopy, pathology, demography) of patients who received surveillance colonoscopy within 5 years after colonoscopic polypectomy. Results: Among 1,794 patients undergoing surveillance colonoscopy within 5 years after colonoscopic polypectomy, 14 suffered from ICC. The mean follow-up time was 2.67 years and the incidence density of ICC was 2.9 cases per 1,000 person-years. 50% of ICCs were found in patients in whom adenomas had been incompletely removed by endoscopic therapy, 36% were missed cancers, and 14% were new cancers. Age >60 years (OR 2.97, 95% CI 2.31-3.82) was significantly associated with interval cancer on the surveillance colonoscopy as were advanced adenoma (OR 1.28, 95% CI 1.01-1.62), the presence of villous (HR 1.38, 95% CI 1.03-1.85) and high-grade dysplasia (OR 1.61, 95% CI 1.07-2.42). Conclusions: Among patients undergoing surveillance colonoscopy within 5 years after polypectomy, the incidence density of ICC was 2.9 cases per 1,000 person-years. The majority of interval cancers originated from incomplete resection of advanced adenomas and missed cancers, which can be prevented by improving endoscopic techniques and selecting an appropriate follow-up time interval.     

大肠息肉电切前活检与电切后的临床病理比较

目的　比较大肠息肉电切前活检与电切后息肉组织的临床病理状况。方法　回顾 5年间在我院接受大肠息肉电切的病例 ,对比分析每一病例电切前、后的临床报告及病理诊断 ,要求 :①电切前后的病理来源于同一息肉 ;②对多次电切病例只取第一次进入病例分析 ;③多发息肉患者取第一枚电切息肉入组 ,其余排除 ;④去除电切前活检已有癌变的病例。结果　在 2 2 0例中符合要求的共 12 0例 ,年龄 5 9 8± 13 3岁 ,其中男性占 65 8% ;活检和电切病理诊断不符合率为 3 3 3 % (4 0 / 12 0 ) (P <0 0 1) ;活检和电切分别诊断腺瘤性息肉 88例 (73 3 % )和 10 0例 (83 3 % ) ,其中不典型增生分别有 2 9例 (3 3 0 % )和 46例 (4 6 0 % ) (P <0 1) ;电切后发现 5例腺瘤性息肉癌变 ,占 5 % (5 / 10 0 ) ,全部来源于 2 7例绒毛状腺瘤 (占其中 18 5 % ) ;活检诊为炎性的息肉和增生性息肉的病例 ,电切后分别有 60 % (15 / 2 5 )和 4/ 7被诊断为其它息肉类型 ;电切后发现活检未曾诊断的幼年性息肉 2例、间质瘤 2例、平滑肌瘤 1例 :绒毛状腺瘤的直径较大 ,为 1 43± 0 5 8cm ,其余各型息肉直径均在 1cm左右 ;癌变息肉直径最大 ,达 1 8± 0 5 7cm ,其最小直径是 1cm。结论　大肠息肉电切前后的临床病理存在较大差异 ,活检     

Number of advanced adenomas on index colonoscopy: Important risk factor for metachronous advanced colorectal neoplasia

Background/AimsAlthough the patients with multiple advanced adenomas (AA) in index colonoscopy may have an increased risk for subsequent advanced colorectal neoplasia (CRN), the current guidelines do not consider this factor. We aimed to compare the risk of metachronous advanced CRN according to the number of AAs.MethodsA total of 2250 patients with ≥1 adenoma at index colonoscopy were included. The patients were divided according to the number of AAs (1, 2 and ≥3 AAs). The relative and 3-year absolute risk of metachronous advanced CRN was compared between the AA groups.ResultsThe relative risk of metachronous advanced CRN was higher in the patients with ≥3 AAs than in the patients with one AA (16.7% vs. 6.8%, p = 0.004). The 3-year absolute risk of metachronous advanced CRN was higher in the patients with ≥3 AAs than in the patients with 1–2 AA (19.4% vs. 6.9%, p = 0.04). Having ≥3 AAs (odds ratio, 5.42; 95% confidence interval 1.75–16.83) was a significant risk factor for developing advanced CRN.ConclusionsThe risk of metachronous advanced CRN in the patients with ≥3 AAs was higher than that in the patients with one or two AAs. More intensive surveillances might be needed for these patient groups.     

Indications for colorectal resection for adenoma before and after polypectomy

Adenomas presenting in colon and rectum require different strategies. Those in the rectum are accessible to local endoanal excision while those in the colon can be removed by endoscopic polypectomy. Essentially the decision in both cases centres around the risk of malignancy. Does the tumour itself contain a focus of malignancy? Where invasion has been demonstrated in the tumour, are the regional lymph nodes involved? Rectal adenomas can be assessed by clinical examination, rectal ultrasound and magnetic resonance imaging. Colonic adenomas on the other hand, are assessed by endoscopic appearances amplified by chromo- and zoom-endoscopy techniques and by endoscopic endosonography. In both locations the decision for surgical resection may be necessary in two clinical circumstances: the preoperative assessment of invasion and following the histopathology report where invasion has been demonstrated. With any adenoma with malignant change, a surgical opinion should be obtained. The decision for surgery depends on the risk of failure of the local excision balanced by the risk of morbidity and mortality following major surgery. Patients' wishes in the light of discussion of clinical and pathological prognostic factors are crucial in making the decision. Surgery is more frequently applied for early colonic than rectal cancers. This is due to two main factors: resective colonic surgery has less complications and mortality than anterior resection and transanal local excision may be more radical than endoscopic colonic polypectomy because it excises the full-thickness rectal wall.     

Prognostic factors in colorectal carcinomas arising in adenomas: implications for lesions removed by endoscopic polypectomy

Endoscopic polypectomy has become the preferred technique for the removal of most colorectal adenomas. Whether polypectomy alone or segmental colectomy is the appropriate management of the patient whose adenoma contains carcinoma is a controversial issue. We studied 129 colorectal carcinomas that arose in adenomas and in which invasion was no deeper than the submucosa of the underlying colonic wall. The following factors were evaluated: location; gross appearance (sessile versus pedunculated); histologic type of adenoma (tubular, villous, mixed); grade of carcinoma; level of invasion (0--carcinoma confined to the mucosa, 1--head, 2--neck, 3--stalk, 4--submucosa of underlying colonic wall); vascular invasion; and adequacy of excisional margins. Patients were divided into two groups with respect to outcome: adverse (dead from colorectal carcinoma, alive with colorectal carcinoma or positive nodes on colectomy), and favorable (absence of above). Sixty-three patients were treated by polypectomy alone and 66 by colectomy (21 preceded by polypectomy); there were no operative deaths. Mean follow-up was 81 mo. None of 65 patients with carcinoma confined to the mucosa had an adverse outcome, but 8 of 64 patients with invasive carcinoma did. Level 4 invasion (p less than 0.001) and rectal location (p = 0.025) were the only statistically significant adverse prognostic factors. Seven of 28 level 4 lesions and six of 42 rectal lesions had an adverse outcome; level 4 lesions were overrepresented in the rectum (14 of 42; p = 0.032). We conclude that the level of invasion should be the major factor in determining prognosis for the management of carcinoma arising in an adenoma.     

内镜下注射肾上腺素-盐水溶液分块摘除结直肠无蒂大息肉

目的探讨安全有效地在内镜下摘除结、直肠扁平无蒂大息肉。方法先在病变的基底部粘膜下层分点注射肾上腺素-盐水溶液,使病变部隆起,然后再在肠镜下用圈套分块电凝摘除。结果本院内镜室用此法治疗结直肠扁平无蒂息肉24例,所有病变直径均大于2cm,其中2～3cm17例,3.1～4cm6例,＞5cm1例。术后病理为腺瘤21例,早期大肠癌3例,均经内镜根治,经随访3例大肠癌均无复发。本组未出现出血或穿孔等并发症。结论结肠镜下注射肾上腺素-盐水溶液后,分块摘除扁平及无蒂的息肉是较安全、有效的o