Colorectal polyps are an important albeit uncommon cause of rectal bleeding in children. Colonoscopy promotes both rapid and accurate diagnosis and the opportunity for immediate therapeutic polypectomy. A 10 year audit of polyps diagnosed and treated endoscopically has been undertaken in the children's endoscopy unit. Twenty nine polyps were diagnosed from 730 colonoscopies; 24 were juvenile, two inflammatory, two Peutz-Jeghers, and one an adenomatous polyp. All but one of the juvenile polyps were solitary. All children had bleeding per rectum as one of the major presenting features. About two thirds of the patients were under the age of 5 years; the mean age was 5.6 years. Most of the juvenile polyps were on the left side of the colon; 41% were distal to the sigmoid colon. However polyps were found throughout the colon, indicating that total colonoscopy is wise and rewarding in any child with persistent and intermittent rectal bleeding.
The clinical spectrum, histology, and endoscopic features of colonic polyps in the pediatric age group were studied to evaluate the role of colonoscopy in children suspected of having colonic polyps.
Seventy-six patients with colorectal polyps were studied. Investigations included barium enema (n=6), sigmoidoscopy (n=17), and colonoscopy (n=53) at the initial visit. Colonoscopy was also performed in 23 patients who received barium enema or sigmoidoscopy. Data related to age, gender, family history, signs, symptoms, size, location, polyp types, and associated diseases were collected and analyzed.
Among the 76 patients, juvenile polyps were detected in 58 (76.3%), potentially premalignant polyposis in 17 (22.4%), familial adenomatous polyposis in 11 (14.5%), Peutz-Jegher syndrome in 4 (5.3%), and juvenile polyposis syndrome in 2 (2.6%). Twenty-two patients (28.9%) had polyps in the upper colon. All patients with potentially malignant polyps had polyps in both the upper colon and rectosigmoid colon.
Although most of the children with colorectal polyps had juvenile polyps, a significant number of cases showed multiple premalignant and proximally located polyps. This finding emphasizes the need for a colonoscopy in such patients. Thus, the risk of malignant change, particularly in children with multiple polyps, makes surveillance colonoscopy necessary.
Children; Colonoscopy; Colonic polyps
Pre-existing polyps, especially large polyps, are known to be the major source for colorectal cancer, but there is limited available information about factors that are associated with polyp size and polyp growth. We aim to determine factors associated with polyp size in different age groups.
Colonoscopy data were prospectively collected from 67 adult gastrointestinal practice sites in the United States between 2002 and 2007 using a computer-generated endoscopic report form. Data were transmitted to and stored in a central data repository, where all asymptomatic white (n = 78352) and black (n = 4289) patients who had a polyp finding on screening colonoscopy were identified. Univariate and multivariate analysis of age, gender, performance site, race, polyp location, number of polyps, and family history as risk factors associated with the size of the largest polyp detected at colonoscopy.
In both genders, size of the largest polyp increased progressively with age in all age groups (P < .0001). In subjects ≥ 80 years the relative risk was 1.55 (95% CI, 1.35-1.79) compared to subjects in the youngest age group. With the exception of family history, all study variables were significantly associated with polyp size (P < .0001), with multiple polyps (≥ 2 versus 1) having the strongest risk: 3.41 (95% CI, 3.29-3.54).
In both genders there is a significant increase in polyp size detected during screening colonoscopy with increasing age. Important additional risk factors associated with increasing polyp size are gender, race, polyp location, and number of polyps, with polyp multiplicity being the strongest risk factor. Previous family history of bowel cancer was not a risk factor.
Colorectal; colon; polyps; colonoscopy; cancer; size
BACKGROUND: Although sulindac is known to cause regression of colorectal adenomatous polyps in familial adenomatous polyposis, less is known about the effect of sulindac on sporadic adenomas. The precise mechanisms of these effects also remain to be determined. AIMS: Sulindac was given to patients with sporadic colorectal adenomatous polyps to evaluate its effects on them, and histological analysis was performed to elucidate the mechanism of the polyp regression, as well the kind of adenomatous polys that are susceptible to the agent. SUBJECTS: 20 adenomatous polyps in 15 patients were studied. METHODS: Sulindac (300 mg daily) was given for four months, followed by colonoscopy with removal of the residual polyps. Polyp size, degree of atypia, inflammatory cell infiltration in the polyps, and immunostaining for mutant p53 product were evaluated before and after treatment. RESULTS: 13 of the 20 polyps shrank or disappeared. Patient sex, polyp location, size, degree of atypia, or p53 mutation did not affect the response, but polyps in older patients were more sensitive to sulindac. The degree of atypia or inflammatory cell infiltration was not affected by the treatment. A polyp containing a focal cancer was unresponsive. CONCLUSIONS: Sulindac can cause regression of sporadic colorectal adenomatous polyps.
AIM: To support probe-based confocal laser endomicroscopy (pCLE) diagnosis by designing software for the automated classification of colonic polyps.
METHODS: Intravenous fluorescein pCLE imaging of colorectal lesions was performed on patients undergoing screening and surveillance colonoscopies, followed by polypectomies. All resected specimens were reviewed by a reference gastrointestinal pathologist blinded to pCLE information. Histopathology was used as the criterion standard for the differentiation between neoplastic and non-neoplastic lesions. The pCLE video sequences, recorded for each polyp, were analyzed off-line by 2 expert endoscopists who were blinded to the endoscopic characteristics and histopathology. These pCLE videos, along with their histopathology diagnosis, were used to train the automated classification software which is a content-based image retrieval technique followed by k-nearest neighbor classification. The performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists was compared with that of automated pCLE software classification. All evaluations were performed using leave-one-patient-out cross-validation to avoid bias.
RESULTS: Colorectal lesions (135) were imaged in 71 patients. Based on histopathology, 93 of these 135 lesions were neoplastic and 42 were non-neoplastic. The study found no statistical significance for the difference between the performance of automated pCLE software classification (accuracy 89.6%, sensitivity 92.5%, specificity 83.3%, using leave-one-patient-out cross-validation) and the performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists (accuracy 89.6%, sensitivity 91.4%, specificity 85.7%). There was very low power (< 6%) to detect the observed differences. The 95% confidence intervals for equivalence testing were: -0.073 to 0.073 for accuracy, -0.068 to 0.089 for sensitivity and -0.18 to 0.13 for specificity. The classification software proposed in this study is not a “black box” but an informative tool based on the query by example model that produces, as intermediate results, visually similar annotated videos that are directly interpretable by the endoscopist.
CONCLUSION: The proposed software for automated classification of pCLE videos of colonic polyps achieves high performance, comparable to that of off-line diagnosis of pCLE videos established by expert endoscopists.
Colorectal neoplasia; Computer-aided diagnosis; Content-based image retrieval; Nearest neighbor classification software; Probe-based confocal laser endomicroscopy
The effectiveness of screening colonoscopy in decreasing the incidence of colorectal cancer (CRC) is largely dependent on the detection of polyps and the quality of the procedure. Several key quality measures have been proposed to improve the effectiveness of screening colonoscopies.
To evaluate quality indicators of screening colonoscopy in a tertiary hospital.
All CRC screening colonoscopies performed between 2005 and 2009 in a single tertiary center were reviewed for internationally accepted quality measures.
Of the 1545 individuals who underwent first-time screening colonoscopy 38% were male and 62% were female. The mean age of the patients was 60.4 years and the mean difference in ages was ± 10.3 years. Cecal intubation rate was 91% (1336), however ileocecal valve photo documentation was performed in only 81% (1248) colonoscopies. The quality of bowel preparation was classified as: good 76% (1171), reasonable 11% (174), and poor 13% (200). Polyp detection rate (PDR) was 33% (503). The prevalence of polyps ≥1 cm in size was 5% (82). PDR was significantly higher in men than in women (44%  vs 25% , P = 0.0001). Other factors significantly influencing PDR were quality of bowel preparation (odds ratio [OR]: 1.28, 95% confidence interval [CI]: 0.9–1.6) and age over 50 (OR: 1.9, 95% CI: 1.3–2.9). Left colonic polyps were associated with a risk ratio of 2.3 (95% CI: 1.8–2.9) of lesions in the other colonic segments compared to no polyps in the left colon. None of the colonoscopists reported withdrawal time.
Cecal intubation rate and quality of bowel preparation were suboptimal. The polyp detection rate compares favorably to accepted standards and its main determinants are male sex, age >50 years, quality of bowel preparation, and the presence of left colonic polyps.
colorectal cancer; screening colonoscopy; quality indicators
AIM: To determine whether folic acid supplementation will reduce the recurrence of colorectal adenomas, the precursors of colorectal cancer, we performed a double-blind placebo-controlled trial in patients with adenomatous polyps.
METHODS: In the current double-blind, placebo-controlled trial at this VA Medical Center, patients with colorectal adenomas were randomly assigned to receive either a daily 5 mg dose of folic acid or a matched identical placebo for 3 years. All polyps were removed at baseline colonoscopy and each patient had a follow up colonoscopy at 3 years. The primary endpoint was a reduction in the number of recurrent adenomas at 3 years.
RESULTS: Of 137 subjects, who were eligible after confirmation of polyp histology and run-in period to conform compliance, 94 completed the study; 49 in folic acid group and 45 in placebo group. Recurrence of adenomas at 3-year was compared between the two groups. The mean number of recurrent polyps at 3-year was 0.36 (SD, 0.69) for folic acid treated patients compared to 0.82 (SD, 1.17) for placebo treated subjects, resulting in a 3-fold increase in polyp recurrence in the placebo group. Patients below 70 years of age and those with left-sided colonic adenomas or advanced adenomas responded better to folic acid supplementation.
CONCLUSION: High dose folic acid supplementation is associated with a significant reduction in the recurrence of colonic adenomas suggesting that folic acid may be an effective chemopreventive agent for colorectal neoplasia.
Folic acid; Adenoma; Colorectal cancer
BACKGROUND—Anthranoid laxatives are the most commonly used purgatives in the therapy of acute and chronic constipation. Recent experimental data and a prospective cohort study provide evidence of a possible risk of anthranoid use for the development of colorectal neoplasms.
MATERIALS AND METHODS—We performed a prospective case control study at the University of Erlangen to investigate the risk of anthranoid laxative use for the development of colorectal adenomas or carcinomas. A total of 202 patients with newly diagnosed colorectal carcinomas, 114 patients with adenomatous polyps, and 238 patients (controls) with no colorectal neoplasms who had been referred for total colonoscopy were studied. The use of anthranoid preparations was assessed by standardised interview, and endoscopically visible or microscopic melanosis coli was studied by histopathological examination.
RESULTS—There was no statistically significant risk of anthranoid use for the development of colorectal adenomas (unadjusted odds ratio 1.0; 95% CI 0.5-1.9) or carcinomas (unadjusted odds ratio 1.0; 95% CI 0.6-1.8). Even after adjustment for the risk factors age, sex, and blood in the stools by logistic regression analysis the odds ratio for adenomas was 0.84 (95% CI 0.4-1.7) and for carcinomas 0.93 (95% CI 0.5-1.7). Also, there were no differences between the patient and control groups for duration of intake. Macroscopic and high grade microscopic melanosis coli were not significant risk factors for the development of adenomas or carcinomas.
CONCLUSION—Neither anthranoid laxative use, even in the long term, nor macroscopic or marked microscopic melanosis coli were associated with any significant risk for the development of colorectal adenoma or carcinoma.
Keywords: anthranoid laxatives; melanosis coli; colorectal adenoma; colorectal carcinoma
To determine the prevalence of serrated colorectal polyps in the King AbdulAziz University Hospital population and to review the current classification of colorectal serrated polyps with emphasis on morphological features.
Materials and Methods:
This retrospective study used cases diagnosed with serrated colorectal polyps at the histopathology laboratory of King AbdulAziz University Hospital during last five years (2004-2008). The slides were reexamined microscopically and the lesions were renamed according to the terminology discussed in this article.
Diagnosed hyperplastic polyps represented 12.3% of all colorectal polyps submitted to our laboratory during the study period. However, the false positive rate was found to be 42.5%. Of the truly diagnosed serrated polyps, the most common subtype is the microvesicular serrated polyps. The majority of the serrated colorectal polyps was found in males, with a wide age range.
The prevalence of serrated colorectal polyps in our geographic area seems to be similar to that in western populations.
Dysplastic serrated polyps; non-dysplastic serrated polyps; serrated colorectal polyps
Background—Malignant colorectal polyps are
defined as endoscopically removed polyps with cancerous tissue which
has invaded the submucosa. Various histological criteria exist for
managing these patients.
Aims—To determine the significance of
histological findings of patients with malignant polyps.
Methods—Five pathologists reviewed the specimens
of 85 patients initially diagnosed with malignant polyps. High risk
malignant polyps were defined as having one of the following:
incomplete polypectomy, a margin not clearly cancer-free, lymphatic or
venous invasion, or grade III carcinoma. Adverse outcome was defined as
residual cancer in a resection specimen and local or metastatic recurrence in the follow up period (mean 67months).
Results—Malignant polyps were confirmed in
70 cases. In the 32 low risk malignant polyps, no adverse outcomes
occurred; 16(42%) of the 38 patients with high risk polyps had
adverse outcomes (p<0.001). Independent adverse risk factors were
incomplete polypectomy and a resected margin not clearly cancer-free;
all other risk factors were only associated with adverse outcome when
Conclusion—As no patients with low risk malignant
polyps had adverse outcomes, polypectomy alone seems sufficient for
these cases. In the high risk group, surgery is recommended when either of the two independent risk factors, incomplete polypectomy or a
resection margin not clearly cancer-free, is present or if there is a
combination of other risk factors. As lymphatic or venous invasion or
grade III cancer did not have an adverse outcome when the sole risk
factor, operations in such cases should be individually assessed on the
basis of surgical risk.
malignant polyps; colon cancer; colonoscopy; polypectomy; histology
AIM: To estimate the prevalence of colorectal cancer (CRC) in patients with long lasting colonic symptoms undergoing total colonoscopy; and to establish clinical features predicting its occurrence.
METHODS: This prospective study was carried out in Imam Hospital, Tabriz University of medical sciences, Iran. Continuous patients with long lasting lower gastrointestinal tract symptoms who had the criteria of a colonoscopy were included. The endoscopist visualized the caecum documented by a photo and/or a specimen from terminal ileum.
RESULTS: Four hundred and eighty consecutive symptomatic patients [mean age (SD): 42.73 (16.21)] were included. The prevalence of colorectal neoplasia was 15.3% (34 subjects) and 37.7% (181 subjects) had a completely normal colon. Adenomatous polyps were detected in 56 (11.7%) patients, in 12.3% of men and 10.9% of women. The mean age of the patients with a polyp was significantly higher than the others (49.53 ± 14.16 vs 41.85 ± 16.26, P = 0.001). Most of the adenomatous polyps were left sided and tubular; only 22.5% of polyps were more than 10 mm. Cancer was detected in 16 (3.6%) of our study population, which was mostly right sided (57.2%). The mean age of patients with cancer was significantly higher than the others (60.25 ± 8.26 vs 42.13 ± 16.08, P < 0.005) and higher than patients with polyps [60.25 (8.26) vs 49.53 (1.91) (P < 0.0005)]. None of the symptoms (diarrhea, abdominal pain, rectal bleeding, constipation, altering diarrhea and constipation, history of cancer, known irritable bowel disease, history of polyp and fissure or family history of cancer) were predictors for cancer or polyps, but the age of the patient and unexplained anemia independently predicted cancer.
CONCLUSION: Less advanced patterns and smaller sizes of adenomas in Iran is compatible with other data from Asia and the Middle East, but in contrast to western countries. Prevalence of colonic neoplasia in our community seems to be lower than that in western population. Colonic symptoms are not predictors for polyps or cancer but unexplained anemia and elder age can predict CRC.
Colorectal cancer; Adenomatous polyp; Colonic symptom; Prevalence; Iran
AIM: To investigate the rates of polyp detection in a mixed risk population using standard definition (SDC) vs high definition colonoscopes (HDC).
METHODS: This was a retrospective cohort comparative study of 3 colonoscopists who each consecutively performed 150 SDC (307, 200 pixel) and 150 HDC (792, 576 pixels) in a community teaching hospital.
RESULTS: A total of 900 colonoscopies were evaluated (mean age 56, 46.8% men), 450 with each resolution. Polyps of any type were detected in 46.0% of patients using SDC and 43.3% with HDC (P = 0.42). There was no significant difference between the overall number of polyps, HDC (397) and SDC (410), detected among all patients examined, (P = 0.73). One or more adenomatous polyps were detected in 24.2% of patients with HDC and 24.9% of patients with SDC colonoscopy (P = 0.82). There was no significant difference between HDC (M = 0.41) and SDC (M = 0.42) regarding adenomatous polyp (P = 0.88) or advanced adenoma (P = 0.56) detection rate among all patients examined.
CONCLUSION: HDC did not improve yield of adenomatous polyp, advanced adenoma or overall polyp detection in a population of individuals with mixed risk for colorectal cancer.
High definition colonoscopy; Colon cancer screening; Adenomatous polyps
Previous studies on life style for colorectal cancer risk suggest that serum lipids and glucose might be related to adenomatous polyps as well as to colorectal carcinogenesis. This case-control study was conducted to investigate the associations between serum lipids, blood glucose, and other factors and the risk of colorectal adenomatous polyp. Male cases with colorectal adenomatous polyp, histologically confirmed by colonoscopy (n=134), and the same number of male controls matched by age for men were selected in hospitals in Seoul, Korea between January 1997 and October 1998. Serum lipids and glucose levels were tested after the subjects had fasted for at least 12 hr. Conditional logistic regression showed that there was a significant trend of increasing adenomatous polyp risk with the rise in serum cholesterol level (Ptrend=0.07). Increasing trend for the risk with triglyceride was also seen (Ptrend=0.01). HDL-cholesterol and LDL-cholesterol had increasing trends for the risk, which were not significant. In particular, it was noted that higher fasting blood glucose level reduced the adenomatous polyp risk for men (Ptrend=0.001). This study concluded that both serum cholesterol and triglyceride were positively related to the increased risk for colorectal adenomatous polyp in Korea. Findings on an inverse relationship between serum glucose and the risk should be pursued in further studies.
AIM: To compare the endotics system (ES), a set of new medical equipment for diagnostic colonoscopy, with video-colonoscopy in the detection of polyps.
METHODS: Patients with clinical or familial risk of colonic polyps/carcinomas were eligible for this study. After a standard colonic cleaning, detection of polyps by the ES and by video-colonoscopy was performed in each patient on the same day. In each single patient, the assessment of the presence of polyps was performed by two independent endoscopists, who were randomly assigned to evaluate, in a blind fashion, the presence of polyps either by ES or by standard colonoscopy. The frequency of successful procedures (i.e. reaching to the cecum), the time for endoscopy, and the need for sedation were recorded. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the ES were also calculated.
RESULTS: A total of 71 patients (40 men, mean age 51.9 ± 12.0 years) were enrolled. The cecum was reached in 81.6% of ES examinations and in 94.3% of colonoscopies (P = 0.03). The average time of endoscopy was 45.1 ± 18.5 and 23.7 ± 7.2 min for the ES and traditional colonoscopy, respectively (P < 0.0001). No patient required sedation during ES examination, compared with 19.7% of patients undergoing colonoscopy (P < 0.0001). The sensitivity and specificity of ES for detecting polyps were 93.3% (95% CI: 68-98) and 100% (95% CI: 76.8-100), respectively. PPV was 100% (95% CI: 76.8-100) and NPV was 97.7% (95% CI: 88-99.9).
CONCLUSION: The ES allows the visualization of the entire colonic mucosa in most patients, with good sensitivity/specificity for the detection of lesions and without requiring sedation.
Colonoscopy; Diagnosis; Endotics system; Polyps; Sedation
Attenuated familial adenomatous polyposis (AFAP) is a variant of familial adenomatous polyposis with fewer than one hundred colorectal polyps and a later age of onset of the cancer. Here, we report two cases of AFAP within family members. Each patient demonstrated the same novel germ line mutation in exon 15 of the adenomatous polyposis coli (APC) gene and was successfully managed with sulindac after refusal to perform colectomy: a 23-year-old man with incidentally diagnosed gastric adenoma and fundic gland polyps underwent colonoscopy, and fewer than 100 colorectal polyps were found; a 48-year-old woman who happened to be the mother of the 23-year-old man also showed fewer than 100 colorectal polyps on colonoscopy. Genetic analysis revealed a novel frameshift mutation in exon 15 of the APC gene. The deletion of adenine-guanine with the insertion of thymine in c.3833-3834 resulted in the formation of stop codon 1,287 in both patients. The patients were treated with sulindac due to their refusal to undergo colectomy. The annual follow-up upper endoscopy and colonoscopy in the following 2 years revealed significant regression of the colorectal polyps in both patients.
Attenuated familial adenomatous polyposis; Mutation; APC; Exon 15
Background & Aims
Conventional colonoscopy misses some neoplastic lesions. We compared the sensitivity of chromoendoscopy and colonoscopy with intensive inspection for detecting adenomatous polyps missed by conventional colonoscopy.
Fifty subjects with a history of colorectal cancer or adenomas underwent tandem colonoscopies at one of 5 centers of the Great-Lakes New England Clinical Epidemiology and Validation Center of the Early Detection Research Network. The first exam was a conventional colonoscopy with removal of all visualized polyps. The second exam was randomly assigned as either pan-colonic indigocarmine chromoendoscopy or standard colonoscopy with intensive inspection lasting ≥20 minutes. Size, histology, and numbers of polyps detected on each exam were recorded.
Twenty-seven subjects were randomized to a second exam with chromoendoscopy and 23 underwent intensive inspection. Forty adenomas were identified on the first standard colonoscopies. The second colonoscopies detected 24 additional adenomas; 19 were found using chromoendoscopy and 5 using intensive inspection. Chromoendoscopy found additional adenomas in more subjects than intensive inspection (44% vs. 17%) and identified significantly more missed adenomas per subject (0.7 vs 0.2, p<0.01). Adenomas detected with chromoendoscopy were significantly smaller (mean size 2.66±0.97mm) and were more often right-sided. Chromoendoscopy was associated with more normal tissue biopsies and longer procedure times than intensive inspection. After controlling for procedure time, chromoendoscopy detected more adenomas and hyperplastic polyps compared with colonoscopy using intensive inspection alone.
Chromoendoscopy detected more polyps missed by standard colonoscopy than did intensive inspection. The clinical significance of these small missed lesions warrants further study.
AIM: To compare the site, age and gender of cases of colorectal cancer (CRC) and polyps in a single referral center in Rome, Italy, during two periods.
METHODS: CRC data were collected from surgery/pathology registers, and polyp data from colonoscopy reports. Patients who met the criteria for familial adenomatous polyposis, hereditary non-polyposis colorectal cancer syndrome or inflammatory bowel disease were excluded from the study. Overlap of patients between the two groups (cancers and polyps) was carefully avoided. The χ2 statistical test and a regression analysis were performed.
RESULTS: Data from a total of 768 patients (352 and 416 patients, respectively, in periods A and B) who underwent surgery for cancer were collected. During the same time periods, a total of 1693 polyps were analyzed from 978 patients with complete colonoscopies (428 polyps from 273 patients during period A and 1265 polyps from 705 patients during period B). A proximal shift in cancer occurred during the latter years for both sexes, but particularly in males. Proximal cancer increased > 3-fold in period B compared to period A in males [odds ratio (OR) 3.31, 95%CI: 2.00-5.47; P < 0.0001). A similar proximal shift was observed for polyps, particularly in males (OR 1.87, 95%CI: 1.23-2.87; P < 0.0038), but also in females (OR 1.62, 95%CI: 0.96-2.73; P < 0.07).
CONCLUSION: The prevalence of proximal proliferative colonic lesions seems to have increased over the last decade, particularly in males.
Colorectal cancer; Polyp; Location; Colonoscopy; Surgery
Most colorectal cancers develop from adenomatous polyps. National guidelines recommend surveillance colonoscopy within 5 years after such polyps are removed.
To determine whether surveillance colonoscopy can be increased among overdue patients by reminders to their primary physicians.
Randomized, controlled trial of patient-specific reminders mailed to 141 physicians in 2 Massachusetts primary care networks during April, 2006.
Seven hundred seventeen patients who had colorectal adenomas removed during 1995 through 2000 and no follow-up colonoscopy identified via automated review of electronic records through March, 2006.
Measurements and Main Results
The use of colonoscopy and detection of new adenomas or cancer were assessed at 6 months by a blinded medical record review in all patients. Among 358 patients whose physicians received reminders, 33 (9.2%) patients underwent colonoscopy within 6 months, compared with 16 (4.5%) of 359 patients whose physicians did not receive reminders (P = 0.009). In prespecified subgroups, this effect did not differ statistically between 2 primary care networks, elderly and nonelderly patients, or women and men (all P > 0.60 by Breslow–Day test). New adenomas or cancer were detected in 14 (3.9%) intervention patients and 6 (1.7%) control patients (P = 0.06), representing 42.4% and 37.5% of patients who underwent colonoscopy in each group, respectively. Despite using advanced electronic health records to identify eligible patients, 22.5% of enrolled patients had a prior follow-up colonoscopy ascertained only by visual record review, and physicians reported 27.9% of intervention patients were no longer active in their practice.
Among patients with prior colorectal adenomas, physician reminders increased the use of surveillance colonoscopy, but better systems are needed to identify eligible patients (ClinicalTrials.gov ID number NCT00397969).
colorectal neoplasms; adenomatous polyps; colonic polyps; colonoscopy; quality of health care; primary health care; randomized controlled trials; Massachusetts
Colorectal cancer (CRC) screening rates are currently suboptimal. Blood-based screening could improve rates of earlier detection for CRC and adenomatous colorectal polyps. In this study, we evaluated the feasibility of plasma-based detection of early CRC and adenomatous polyps using array-mediated analysis methylation profiling of 56 genes implicated in carcinogenesis. Methylation of 56 genes in patients with stage I and II CRC (N=30) and those with adenomatous polyps (N=30) were compared to individuals who underwent colonoscopy and were found to have neither adenomatous changes nor CRC. Composite biomarkers were developed for adenomatous polyps and CRC, and their sensitivity and specificity was estimated using five-fold cross validation. Six promoters (CYCD2, HIC1, PAX 5, RASSF1A, RB1, and SRBC) were selected for the biomarker, which differentiated CRC patients and controls with 84% sensitivity and 68% specificity. Three promoters (HIC1, MDG1, and RASSF1A) were selected for the biomarker, which differentiated patients with adenomatous polyps and controls with sensitivity of 55% and specificity of 65%. Methylation profiling of plasma DNA can detect early CRC with significant accuracy and shows promise as a methodology to develop biomarkers for CRC screening.
cell-free; plasma; methylation; colorectal; polyp; cancer
Background—Virtual colonoscopy is a potentially
powerful tool for non-invasive colorectal evaluation. In vitro studies
have established its accuracy in simulated polyp detection but little data exist regarding its use in clinical practice.
Aims—To evaluate the ability of virtual
colonoscopy to detect colorectal cancers and polyps in patients with
endoscopically proven colorectal neoplasms and to correlate the
findings of virtual colonoscopy with those of conventional colonoscopy,
surgery, and histopathology.
Patients—Thirty eight patients with endoscopic
findings suggestive of colorectal carcinoma.
Methods—Virtual colonoscopy was performed using
thin section helical computed tomography (CT) of the abdomen and pelvis
after rectal insufflation of room air. Commercially available software was used to generate endoscopic "fly through" examinations of the
colon from the CT data. Results were correlated with the findings of
conventional colonoscopy and with the surgical and histopathological outcome in each case.
Results—Thirty eight pathologically proven
colorectal cancers and 23 adenomatous polyps were present. On virtual
colonoscopy, all cancers and all polyps measuring greater than 6 mm in
size were identified; there were two false positive reports of polyps. On conventional colonoscopy, there was one false positive report of a
malignant sigmoid stricture; four subcentimetre polyps were overlooked.
Virtual colonoscopy enabled visualisation of the entire colon in 35 patients; conventional colonoscopy was incomplete in 14 patients.
Virtual colonoscopy correctly localised all 38cancers, compared with
32 using conventional colonoscopy.
Conclusion—Virtual colonoscopy is a feasible
method for evaluating the colon; it may have role in diagnosis of
colorectal cancer and polyps.
colonic neoplasms; computed tomography; computer
BACKGROUND AND AIMS: Most colorectal cancers (CRC) arise in colorectal adenomas. A case-control study was conducted to see whether a family history of CRC is associated with a higher prevalence of colorectal adenomas. SUBJECTS: Subjects were drawn from all patients who underwent colonoscopy at the Royal Brisbane Hospital between 1980-1982 and 1985, and included 141 cases with colorectal adenomas diagnosed at colonoscopy and 882 controls who were free of polyps at colonoscopy. METHODS: The prevalence of family history of CRC was compared between patients with adenomas and negative colonoscopy controls. RESULTS: Overall, patients with one first degree relative with CRC were at no greater risk for adenomas at colonoscopy than patients with no family history (odds ratio (OR) = 0.8, 95% confidence intervals (CI) = 0.4, 1.5). Patients with two or more affected first degree relatives had a more than doubled risk for adenomas (OR = 2.3, 95% CI = 0.5, 8.2), and were also more likely to carry moderately or severely dysplastic adenomas (OR = 14.1, 95% CI = 2.0, 62.9). CONCLUSIONS: These findings are consistent with the hypothesis that some families, in addition to those with familial adenomatous polyposis, have an increased susceptibility to develop colorectal adenomas, and that adenomas in such families may have a greater tendency to undergo malignant transformation.
In the National Polyp Study (NPS), colorectal cancer was prevented by colonoscopic removal of adenomatous polyps. We evaluated the long-term effect of colonoscopic polypectomy in a study on mortality from colorectal cancer.
We included in this analysis all patients prospectively referred for initial colonoscopy (between 1980 and 1990) at NPS clinical centers who had polyps (adenomas and nonadenomas). The National Death Index was used to identify deaths and to determine the cause of death; follow-up time was as long as 23 years. Mortality from colorectal cancer among patients with adenomas removed was compared with the expected incidence-based mortality from colorectal cancer in the general population, as estimated from the Surveillance Epidemiology and End Results (SEER) Program, and with the observed mortality from colorectal cancer among patients with non-adenomatous polyps (internal control group).
Among 2602 patients who had adenomas removed during participation in the study, after a median of 15.8 years, 1246 patients had died from any cause and 12 had died from colorectal cancer. Given an estimated 25.4 expected deaths from colorectal cancer in the general population, the standardized incidence-based mortality ratio was 0.47 (95% confidence interval [CI], 0.26 to 0.80) with colonoscopic polypectomy, suggesting a 53% reduction in mortality. Mortality from colorectal cancer was similar among patients with adenomas and those with nonadenomatous polyps during the first 10 years after polypectomy (relative risk, 1.2; 95% CI, 0.1 to 10.6).
These findings support the hypothesis that colonoscopic removal of adenomatous polyps prevents death from colorectal cancer. (Funded by the National Cancer Institute and others.)
We tested the correlation between diabetes and aggressiveness of colorectal polyps in diabetic patients and matched non-diabetic controls. We retrospectively studied 3,505 type 2 diabetes (T2DM) patients without gastrointestinal symptoms who underwent colonoscopy for colorectal cancer at Samsung Medical Center, Seoul, Korea from August 1995 to August 2009. We matched 495 non-diabetic subjects with colon polyps to the diabetic patients in whom polyps were detected by year of colonoscopy, age, sex and body mass index (BMI). Among the 3,505 T2DM patients screened, 509 were found to have 1,136 colon polyps. Those with diabetes had a greater proportion of adenomatous polyps (62.8% vs 53.6%) compared to the control. Multivariate logistic regression analysis identified DM, male gender, age and BMI as independent risk factors for multiple polyps (more than three polyps). Polyp multiplicity in diabetic patients was significantly associated with male gender (OR 2.360, P = 0.005), age (OR 1.033, P = 0.005) and BMI (OR 1.077, P = 0.028). Neither aspirin nor metformin use affected either size or number of polyps in diabetic patients. Male patients older than 65 yr with T2DM and BMI greater than 25 have increased risk for multiple adenomatous polyps and should be screened with colonoscopy to prevent colorectal cancer.
Diabetes Mellitus; Colonic Polyps; Colorectal Neoplasms
In recent years, the incidence of early-stage colorectal cancer (CRC) has markedly increased in the population within the Republic of Korea. The aim of this study was to evaluate the clinicopathologic features of adenomatous polyps in TNM stage I CRC patients and in the general population.
Between March 2003 and September 2009, 168 patients with stage I CRC were enrolled in this study. In addition, the records of 4,315 members of the general population without CRC, as determined by colonoscopy during a health check-up, were reviewed.
Of the 168 patients with stage I CRC, 68 (40.5%) had coexisting colorectal adenomatous polyps and of the 4,315 members of the general population, 1,112 (26.0%) had coexisting adenomatous polyps (P = 0.006). The prevalences of adenomatous polyp multiplicity in early CRC and in the general population were 32% and 15%, respectively (P = 0.023). Patients with coexisting adenomatous polyps had a higher frequency of tubulovillous or villous adenomas than members of the general population with polyps (7.5% vs. 2.0%, P = 0.037). Furthermore, a subgroup analysis showed that the occurrence (44% vs. 34%, P = 0.006) and the multiplicity (32% vs. 15%, P = 0.023) of adenomatous polyps were greater for T2 than T1 cancer.
The prevalence and the multiplicity of adenomatous polyps in TNM stage I CRC is higher than it is in the general population. The findings of this study suggest that depth of invasion of early stage CRC affects the prevalence and the number of adenomatous polyps in the remaining colon and rectum.
Colorectal carcinoma; Adenomatous polyp; Stage I; Colonoscopy
Patients presenting to a district general hospital (DGH) with colorectal neoplasms have been studied before and after the introduction of a colonoscopy service, in order to investigate the diagnostic, therapeutic and economic benefits of performing colonoscopy in preference to sigmoidoscopy and double contrast barium enema (DCBE). Colonoscopy led to a 3-fold increase in the incidence of colonic polyps, and 22% of all adenomas showed worrying features. Severe dysplasia and malignancy was seen most frequently in large adenomas (greater than 2 cm), and in those with a villous component. Laparotomy was avoided in 31 patients with proximal polyps, giving colonoscopy an added therapeutic and economic advantage over sigmoidoscopy and DCBE. Colonoscopy was used less frequently to detect colonic carcinomas, as over half of these were rectal, or presented as emergencies. These findings confirm the value of performing colonoscopy in patients who present with colorectal symptoms.