Pathologic Features of Initial Adenomas as Predictors for Metachronous Adenomas of the Rectum
04 Nov 1998-Journal of the National Cancer Institute (Oxford University Press)-Vol. 90, Iss: 21, pp 1661-1665
TL;DR: The risk of metachronous adenomas is closely related to the pathology of initial adenomatous polyps, thus allowing identification of a high-risk group of adenoma patients for close surveillance after their initial polypectomy.
Abstract: Background Colorectal cancer is the third most common cancer in the world, arising mostly from pre-existing adenomatous polyps (adenomas) of the large bowel. Patients with colorectal adenomas are at increased risk of colorectal cancer because of a high recurrence rate for adenomas. We followed a cohort of 1490 patients with rectal adenomas to determine whether recurrence might be related to pathologic characteristics of the initial adenomas. Methods The patients were identified in Haining County, China, from 1977 through 1978 by means of examination with a 15-cm rigid sigmoidoscope. They were followed by endoscopic examination at years 2, 4, 6, 11, and 16 after their initial polypectomy. New adenomas in the rectum were identified in 280 patients in these follow-up examinations. Results Statistically significant twofold to threefold elevated risks of metachronous (recurrent) adenomas were observed for patients who had more than two initial adenomas or whose most advanced initial adenoma was more than 1.0 cm in size, was of villous/tubulovillous type, or showed moderate to severe dysplasia. Much stronger associations were observed for advanced metachronous neoplasms, which are defined as cancers or adenomas with severe dysplasia, with multivariate adjusted relative risks (95% confidence interval) of 4.2 (1.8-9.9) for a large initial adenoma (>1.0 cm), 8.1 (4.2-15.6) for villous/tubulovillous architecture, and 14.4 (5.0-41.3) for severe dysplasia. In particular, patients who had a large (>1.0 cm) adenoma with severe dysplasia at baseline had a relative risk of 37 (7.8-174.7) of developing advanced metachronous neoplasms compared with patients who had small adenoma(s) with mild dysplasia. Conclusions The risk of metachronous adenomas is closely related to the pathology of initial adenomas, thus allowing identification of a high-risk group of adenoma patients for close surveillance after their initial polypectomy.
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TL;DR: It is indicated that serrated adenomas are lesions with a significant risk of metachronous serratedAdenomas and the development of cancer and the need for the proper recognition and management of serrated Adenomas is emphasized.
Abstract: Serrated adenomas are the precursors of at least 5.8% of colorectal cancers; otherwise little is known of their clinical significance in comparison with conventional adenomas and hyperplastic polyps. We compared the risk of metachronous lesions in colorectal serrated adenomas, conventional adenomas, and hyperplastic polyps. A consecutive series of patients with colorectal polyps first diagnosed from January 1978 to December 1982 and follow-up specimens to the end of 2000 was reviewed, and 239 polyps fulfilling the selection criteria were chosen as index polyps. The type of polyp seen in follow-up correlated significantly with the type of the initial lesion. Serrated adenomas were estimated to grow faster than conventional adenomas, but the incidence of colorectal cancer did not differ significantly between serrated (2/38 [5%]) and conventional adenomas (2.2%). The results indicate that serrated adenomas are lesions with a significant risk of metachronous serrated adenomas and the development of cancer. We emphasize the need for the proper recognition and management of serrated adenomas.
156 citations
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...4 (22-85) Mixed hyperplastic polyp 7 4/3 1....
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TL;DR: Follow-up colonoscopies in patients with adenomas should include careful examination of the proximal colon, and the time interval between follow-up examinations could probably be extended beyond three years in patients who have only one or two distalAdenomas.
Abstract: The identification of groups with a high risk of colorectal adenoma recurrence remains a controversial issue for clinicians. This study was designed to assess the predictive value of initial patient and adenoma characteristics of the three-year recurrence. The study population was composed of 552 patients with resected colorectal adenomas who completed the European Fiber-Calcium Intervention trial. At both baseline and three-year examinations, the characteristics of adenomas were recorded according to a standardized protocol. The main outcomes measured were the three-year overall recurrence, recurrence of multiple adenomas, recurrence of advanced adenomas (size ≥ 1 cm or tubulovillous/villous architecture or moderate/severe dysplasia), and proximal and distal recurrence. A three-year recurrence was observed in 122 patients (22.1 percent), and more than one-half of them had recurrent adenomas on the proximal colon. After adjustment for patient characteristics and treatment allocation, the number of adenomas and their proximal location at baseline were the main predictors of recurrence. In comparison with patients who had one or two adenomas on the distal colon, patients with three or more adenomas with at least one of them located on the proximal colon had a much higher risk of overall recurrence (5.3; 95 percent confidence interval, 2.7–10.3), proximal recurrence (8.5; 95 percent confidence interval, 4.1–18), and advanced adenoma recurrence (5.5; 95 percent confidence interval, 2.4–12.6). Follow-up colonoscopies in patients with adenomas should include careful examination of the proximal colon. The time interval between follow-up examinations could probably be extended beyond three years in patients who have only one or two distal adenomas.
139 citations
Cites background from "Pathologic Features of Initial Aden..."
...severe dysplasia and the risk of advanced adenoma recurrence after 16 years of follow-up.(22) Because colorectal carcinogenesis is a slow process, a long duration of follow-up probably increases the chance of finding predictors of advanced adenoma recurrence....
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...In a long-term, follow-up study of a Chinese population with rectal adenomas, only a borderline association was found between the number of adenomas and the risk of advanced rectal adenomas.(22) On the other hand, two American intervention studies, the Polyp Prevention Study(12) and the Wheat Bran Fiber Study,(13) failed to detect any association with advanced adenomas....
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...from the few studies that examined the recurrence of advanced adenomas.(12,13,19,22,23) Two studies did not find any associations....
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TL;DR: In this paper, the authors suggest that a recommendation from a physician is the most influential factor in determining whether a patient is screened for colorectal cancer, and suggest that evidence-based strategies can help the physician ensure that every appropriate patient leaves the office with the needed recommendation.
Abstract: A recommendation from a physician is the most influential factor in determining whether a patient is screened for colorectal cancer. While the vast majority of primary care physicians report that they screen for colorectal cancer, many patients do not receive the recommendation they need. Evidence-based strategies can help the physician ensure that every appropriate patient leaves the office with the needed recommendation. Choosing an office system that can be implemented by the physician or office staff can fuel efforts to achieve higher screening rates. Reminder systems, tracking systems, communication strategies, and policies that reinforce use of evidence-based guidelines may contribute.
133 citations
National Institutes of Health1, Kaiser Permanente2, Roswell Park Cancer Institute3, University of Arizona4, Ohio State University5, University of Pittsburgh6, Huntsman Cancer Institute7, Veterans Health Administration8, Memorial Sloan Kettering Cancer Center9, Walter Reed Army Institute of Research10
TL;DR: In this paper, the authors found that the risk for recurrence of advanced adenoma within 4 years of follow-up was greater for patients with high-risk adenomas at baseline than for those with low-risk ones at baseline.
Abstract: rence within 4 years of follow-up. The probability of advanced adenoma recurrence was 0.09 (95% CI, 0.07 to 0.11) among patients with high-risk adenomas at baseline and 0.05 (CI, 0.04 to 0.06) among those with low-risk adenomas at baseline. The relative risk for advanced adenoma recurrence for patients with high-risk adenomas versus those with low-risk adenomas at baseline was 1.68 (CI, 1.19 to 2.38) when advanced adenoma recurrence was compared with no advanced adenoma recurrence and 1.76 (CI, 1.26 to 2.46) when advanced adenoma recurrence was compared with no adenoma recurrence. The c-statistics for these 2 comparisons were 0.68 and 0.72, respectively. Limitation: Participants were self-selected and had restrictions on the degree of obesity. Conclusion: Although the risk for recurrence of advanced adenoma within 4 years is greater for patients with high-risk adenomas at baseline than for those with low-risk adenomas, the discrimination of this risk stratification scheme is relatively low.
123 citations
TL;DR: It is found that available and effective screening technologies are not consistently applied, even as new ones are developed, and further advances are emerging out of rigorous clinical testing, which remains the limiting factor in transforming ingenious concepts into useful tools for the prevention of CRC.
104 citations
Cites background from "Pathologic Features of Initial Aden..."
...Several retrospective and prospective studies have shown that adenoma size (typically defined as 1 cm or larger in diameter), villous histology, or multiplicity predict future tumor development [53–56]....
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References
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TL;DR: A model for the genetic basis of colorectal neoplasia that includes the following salient features is presented, which may be applicable to other common epithelial neoplasms, in which tumors of varying stage are more difficult to study.
11,576 citations
TL;DR: The results of the National Polyp Study support the view that colorectal adenomas progress to adenocarcinomas, as well as the current practice of searching for and removing adenomatous polyps to prevent coloreCTal cancer.
Abstract: Background The current practice of removing adenomatous polyps of the colon and rectum is based on the belief that this will prevent colorectal cancer. To address the hypothesis that colonoscopic polypectomy reduces the incidence of colorectal cancer, we analyzed the results of the National Polyp Study with reference to other published results. Methods The study cohort consisted of 1418 patients who had a complete colonoscopy during which one or more adenomas of the colon or rectum were removed. The patients subsequently underwent periodic colonoscopy during an average follow-up of 5.9 years, and the incidence of colorectal cancer was ascertained. The incidence rate of colorectal cancer was compared with that in three reference groups, including two cohorts in which colonic polyps were not removed and one general-population registry, after adjustment for sex, age, and polyp size. Results Ninety-seven percent of the patients were followed clinically for a total of 8401 person-years, and 80 percent returned...
4,310 citations
TL;DR: Evidence is presented which suggests that most cancers of the colon and rectum have evolved through the polyp‐cancer sequence although the majority of adenomas do not become cancerous during a normal adult life span.
Abstract: The malignant potential of adenomas of the colon and rectum varies with size, histological type and grade of epithelial atypia. The adenomatous polyp is usually small and has a low malignant potential, whereas tumors with a villous structure are usually larger and have a much higher cancer rate. Severe atypia is more common in villous adenomas than in adenomatous polyps. Evidence is presented which suggests that most cancers of the colon and rectum have evolved through the polyp-cancer sequence although the majority of adenomas do not becoma cancerous during a normal adult life span. The slow evolution of the polyp-cancer sequence is stressed. The implications of the polyp-cancer sequence for the design of cancer prevention programmes and the study of the aetiology of large bowel cancer are discussed.
1,944 citations
TL;DR: The long-term risk of colorectal cancer after rigid-instrument sigmoidoscopy and polypectomy in 1618 patients with rectosigmoid adenomas who did not undergo surveillance was assessed, finding that surveillance may not be of value because the risk of cancer is so low.
Abstract: Background and Methods Surveillance by repeated colonoscopy is currently recommended for patients with colorectal adenomas. We assessed the long-term risk of colorectal cancer after rigid-instrument sigmoidoscopy and polypectomy in 1618 patients with rectosigmoid adenomas (tumors of the rectum or distal sigmoid colon) who did not undergo surveillance. A total of 22,462 person-years of observation were accrued (mean, 14 years per patient). Results The incidence of subsequent rectal cancer in these patients was similar to that in the general population (standardized incidence ratio, 1.2; 95 percent confidence interval, 0.7 to 2.1). Most rectal cancers developed in patients whose adenomas had been inadequately removed; the risk was very low after complete removal. The risk of subsequent colon cancer depended on the histologic type, size, and number of adenomas in the rectosigmoid. Among 842 patients with a rectosigmoid adenoma that was tubulovillous, villous, or large (≥1 cm), colon cancer developed...
1,018 citations
TL;DR: Colonoscopy performed three years after colonoscopic removal of adenomatous polyps detects important colonic lesions as effectively as follow-up colonoscopy after both one and three years.
Abstract: Background The identification and removal of adenomatous polyps and post-polypectomy surveillance are considered to be important for the control of colorectal cancer. In current practice, the intervals between colonoscopies after polypectomy are variable, often a year long, and not based on data from randomized clinical trials. We sought to determine whether follow-up colonoscopy at three years would detect important colonic lesions as well as follow-up colonoscopy at both one and three years. Methods Patients were eligible if they had one or more adenomas, no previous polypectomy, and a complete colonoscopy and if all their polyps had been removed. They were randomly assigned to have follow-up colonoscopy at one and three years or at three years only. The two study end points were the detection of any adenoma, and the detection of adenomas with advanced pathological features (defined as those >1 cm in diameter and those with high-grade dysplasia or invasive cancer). Results Of 2632 eligible patients, 141...
933 citations