Polyp Diameters Research Articles

Which Drugs are More Effective in Preventing Familial Adenomatous Polyposis Progression based on Network Meta-analysis?

Familial adenomatous polyposis (FAP) is an inherited disorder. At present, an increasing number of medications are being employed to treat FAP; however, only a few have been assessed for their efficacy and safety. Therefore, this study aimed to conduct a network meta-analysis to compare the therapeutic outcomes and adverse drug reactions of all FAP-associated medications. Six relevant databases were searched to identify pertinent randomized controlled trials (RCTs), and information on the dosage and frequency of various drugs was extracted. Additionally, data on changes in polyp counts and dimensions, as well as treatment-related adverse reactions for different medications were collected. The Bayesian method was employed to directly or indirectly compare the impact of different treatment regimens on changes in polyp numbers and diameters, and the safety of the drugs was investigated. CXB at 16 mg/kg/day significantly reduced polyp numbers. Celecoxib at 8 mg/kg/day and sulindac (150 mg twice daily) plus erlotinib (75 mg/day) were effective for tolerant FAP patients. Additionally, EPAFFA 2 g daily and sulindac (150 mg twice daily) plus erlotinib (75 mg/day) emerged as the most effective for reducing polyp size. The most effective treatment for reducing the number of colorectal polyps is celecoxib 16 mg/kg/day. On the other hand, a daily dosage of 2 g EPA-FFA demonstrates the best results in terms of decreasing colorectal polyp diameter.

Estimating the size of colorectal polyps endoscopically: random guess or systematic error?

Size of colorectal polyps reflects potential for malignancy and helps define advanced lesions. Studies measuring ability of endoscopists to estimate polyp size show significant variation. The aim of this study was to determine if there is a linear relationship between endoscopic and pathologic polyp size. Data for adenomas removed completely by snare, in one piece, were retrieved from a prospectively recorded polyp database. Endoscopic estimate of maximum diameter was compared to that on the pathology report by linear regression analysis. There were 126 polyps in 126 patients, 85 men and 41 women. Mean age was 63.2± 12.9 years. Mean endoscopic polyp size was 12.2± 9.3 mm and mean pathology size was 9.3± 6.9 mm. Endoscopically, 16 polyps were ≤ 5 mm, 62 were from 6 to 10 mm, 21 were from 11 to 15 mm, and 27 were from 16 to 55 mm. Twenty-nine polyps were right sided, 86 were left and 11 were rectal. Regression of endoscopic size against pathology size yielded a significant r2 of 0.761. Using the regression formula of endoscopic size=0.7+1.175× pathology size an endoscopic estimate of 10 mm (= advanced adenoma) means a pathologic size of 8 mm. For a pathologic size of 10 mm, an endoscopic estimate of 12 mm is needed. A large polyp is ≥20 mm; for this endoscopist a 20 mm polyp is really 16.4 mm. The relationship between endoscopic and directly measured size is linear over all polyp diameters, and likely represents a systematic error.

Phase II trial of weekly erlotinib dosing to reduce duodenal polyp burden associated with familial adenomatous polyposis

ImportancePatients with familial adenomatous polyposis (FAP) are at markedly increased risk for duodenal adenomas and cancer. Combination sulindac and erlotinib was previously shown to reduce duodenal polyp burden but was...

Terminal digit preference biases polyp size measurements at endoscopy, computed tomographic colonography, and histopathology.

Terminal digit preference bias for "pleasing" numbers has been described in many areas of medicine. The aim of this study was to determine whether endoscopists, radiologists, and pathologists exhibit such bias when measuring colorectal polyp diameters. Colorectal polyp diameters measured at endoscopy, computed tomographic colonography (CTC), and histopathology were collated from a colorectal cancer screening program and two parallel multicenter randomized trials. Smoothing models were fitted to the data to estimate the expected number of polyps at 1-mm increments, assuming no systematic measurement bias. The difference between the expected and observed numbers of polyps was calculated for each terminal digit using statistical modeling. The impact of measurement bias on per-patient detection rates of polyps ≥ 10 mm was estimated for each modality. A total of 92 124 individual polyps were measured by endoscopy (91 670 screening and 454 from trials), 2385 polyps were measured by CTC (1664 screening, 721 trials), and 79 272 were measured by histopathology (78 783 screening, 489 trials). Clustering of polyp diameter measurements at 5-mm intervals was demonstrated for all modalities, both in the screening program and the trials. The statistical models estimated that per-patient detection rates of polyps ≥ 10 mm were over-inflated by 2.4 % for endoscopy, 3.1 % for CTC, and 3.3 % for histopathology in the screening program, with similar trends in the randomized trials. Endoscopists, radiologists, and pathologists all exhibit terminal digit preference when measuring colorectal polyps. This will bias trial data, referral rates for further testing, adenoma surveillance regimens, and comparisons between tests.

Comparative biometry and isotopy of three dominant pennatulacean corals in the Northwest Atlantic

AbstractSpatial and temporal shifts in biometric features were examined in three common deep‐water pennatulacean corals (sea pens) from the Northwest Atlantic: Anthoptilum grandiflorum, Halipteris finmarchica and Pennatula aculeata. These three species show different morphological characters and adaptations to their environment. Analyses of colony length, ratio of peduncle to colony length, weight/length ratio, polyp size and density as well as sclerite shape, location and abundance indicate that their phenotype is modulated by environmental factors (e.g. food availability, currents and sediment type) and antipredator strategies. Moreover, the three species had different carbon and nitrogen stable isotope signatures that could be explain primarily by their different polyp diameters and colony shapes, suggesting that they rely on slightly different food sources (varying proportions of phytodetritus and zooplankton). Finally, sclerites were found only in H. finmarchica and P. aculeata and are not known to occur in A. grandiflorum, except for minute oval bodies inside the peduncle. The Mg/Ca ratio of sclerites differed between the two species and, for P. aculeata, among types of sclerites, evoking different biomineralization pathways related to their functional roles (structural support or defence). Overall, this study provides new information on the ecology of poorly known species, which are ubiquitous and suspected to play an important ecological role in deep‐water ecosystems.

Optimal section thickness for detection of polyps at MR: resolution phantom study.

To determine (1) the sensitivity for detection of small polyps with varying MR slice thicknesses using a resolution phantom; (2) reader confidence in polyp detection; and (3) image acquisition time. A resolution phantom was created using a 3D printer. Polyp morphologies were sessile (height = diameter), flat (height = 1/2 diameter of the base), and pedunculated (stalk length = polyp diameter). Polyp diameters were 5, 7, 10, and 12 mm. Images were acquired with section thicknesses of 5, 3, and 1 mm. Images were independently reviewed by 4 board-certified radiologists who were blinded to phantom design and sequences parameters. Readers recorded maximal polyp diameter and confidence level that a polyp was present on a 1-100 point scale. Image acquisition time was also recorded. All polyps were detected by all 4 readers in the 5-mm-section thickness series. All polyps were detected by 3 readers in the 3- and 1-mm-section thickness series. The fourth reader identified 11/12 polyps in the 3- and 1-mm-section thickness series. Confidence levels were not statistically significantly different for the different section thicknesses (p = 0.28). Increasing the section thickness from 1 to 5 mm decreased image acquisition time from 3 min 54 s to 41 s. Five-millimeter-section thickness was adequate for identification of 5-12 mm polyps regardless of shape. Pending further reduction in acquisition time, this prototype sequence holds promise for segmental imaging of the colon with MR colonography.

PWE-066 Endoscopic Versus Histological Assessment Of Colonic Polyp Size

IntroductionColonic polyp size is a factor in determining management and prognosis of patients. Polyp diameters greater than 9 mm require ongoing colonoscopic surveillance.1 Accurate endoscopic estimation of polyp size can...

Method for Tracking Eye Gaze during Interpretation of Endoluminal 3D CT Colonography: Technical Description and Proposed Metrics for Analysis

To develop an eye-tracking method applicable to three-dimensional (3D) images, where the abnormality is both moving and changing in size. Research ethics committee approval was granted to record eye-tracking data from six inexperienced readers who inspected eight short (<30 seconds) endoluminal fly-through videos extracted from computed tomographic (CT) colonography examinations. Cases included true-positive and false-positive polyp detections from a previous study (polyp diameters, 5-25 mm). Eye tracking was performed with a desk-mounted tracker, and readers indicated when they saw a polyp with a mouse click. The polyp location on each video frame was quantified subsequently by using a circular mask. Gaze data related to each video frame were calculated relative to the visible polyp boundary and used to identify eye movements that pursue a polyp target as it changes size and position during fly-through. Gaze data were then related to positive polyp detections by readers. Tracking eye gaze on moving 3D images was technically feasible. Gaze was successfully classified by using pursuit analysis, and pursuit-based gaze metrics were able to help discriminate different reader search behaviors and methods of allocating visual attention during polyp identification. Of a total of 16 perceptual errors, 15 were recognition errors. There was only one visual search error. The largest polyp (25 mm) was seen but not recognized by five of six readers. Tracking a reader's gaze during endoluminal interpretation of 3D data sets is technically feasible and can be described with pursuit-based metrics. Perceptual errors can be classified into visual search errors and recognition errors. Recognition errors are more frequent in inexperienced readers.

592 TNF-α Treatment Induces Directional IL-8 Secretion in Polarized Caco-2 Cells

Purpose : The arachidonic acid pathway enzymes, cyclooxygenase and 5-lipoxygenase (5LO), have both been shown to modulate cell growth. Many studies have investigated the effects of cyclooxygenase inhibition on human colorectal cancer, but the role of 5LO in colon carcinogenesis has not been well studied. Interestingly, 5LO is a majormediator of hematopoietic immune function. However, its role in relation to tumorigenic myeloid-derived suppressor cells (MDSC) is unknown. The aim of this study was to evaluate if 5LO deficiency suppresses intestinal polyp formation and if this suppression is mediated through the hematopoietic system, namely MDSC's. Methods : We examined the effects of 5LO gene knockouts on ApcΔ468 knockout mice, a model of human familial adenomatous polyposis. APCΔ468/ 5LO-/mice were sacrificed and evaluated at 16 weeks. Age-matched APCΔ468/5LO+/+ mice served as controls. Polyp counts and diameters were measured in both groups. MDSC's were quantified from intestines, mesenteric lymph nodes, and spleens also from both groups, using flow cytometry. To evaluate which compartment's 5LO deficiency was responsible for polyposis suppression, APCΔ468 mice were lethally irradiated and reconstituted with bone marrow from healthy 5LO+/+ mice (wt BM) or 5LO-/mice (5LO-/BM). Polyp counts and MDSC's were also quantified in both reconstitution groups. Results : 5LO null mutation led to a dramatic reduction in the number and size of intestinal polyps. The APCΔ468/ 5LO+/+ group developed 79 + 4 polyps with a median polyp diameter of 2.7mm. In contrast, APCΔ468/5LO-/mice had 46 + 6 polyps with a median diameter of 1.2mm, an approximately 40% and 44% reduction, respectively (P < 0.005). In even greater contrast, the 5LO-/BM group had a 95% reduction in polyp counts compared to the wt BM group (5 + 1 vs 111 + 14, respectively, P < 0.005). MDSC's were reduced in the intestines, mesenteric lymph nodes, and spleens of the APCΔ468/5LO-/and 5LO-/BM groups compared to their respective controls (P < 0.005). Conclusions : These findings provide direct genetic evidence that hematopoietic 5LO has an important role in tumorigenesis which is partially mediated through MDSC expansion. Our data points to 5LO-selective inhibitors as a potential, novel class of therapeutic agents for colorectal polyposis and cancer.

Eicosapentaenoic acid reduces rectal polyp number and size in familial adenomatous polyposis

ObjectiveThe omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) has anticolorectal cancer activity in vitro and in preclinical models. The present study tested whether a novel, enteric-coated formulation of EPA, as...

Does a selective cyclooxygenase-2 inhibitor (tiracoxib) induce clinically sufficient suppression of adenomas in patients with familial adenomatous polyposis? A randomized double-blind placebo-controlled clinical trial

There have been few placebo-controlled randomized double-blind studies of the clinical effects of selective cyclooxygenase-2 (COX-2) inhibitors on the regression of colorectal tumors. This study was designed to examine the regressive effect of a selective COX-2 inhibitor, tiracoxib (JTE-522), on colorectal polyps in patients with familial adenomatous polyposis (FAP), and its safety. Sixty-one patients with FAP diagnosed by Japanese criteria were assigned randomly to receive placebo or JTE-522, at either 150 mg or 200 mg, once daily orally for 26 weeks. Prior to and at the end of the medication period, endoscopy was performed. Adenomas located near an india-ink tattoo injected at the first colonoscopy were identified and measured. The response variables were the percent changes from the baseline in polyp numbers and in specified polyp diameters. Any adverse events that appeared in at least four persons were taken into consideration and compared between the JTE-522 treatment groups and the placebo group. No change in polyp number (median, 0) was observed in any of the three groups. There were no differences between the placebo group and the two treatment groups in the change in polyp size. JTE-522 was well tolerated. Our findings, in keeping with other reports on COX-2 inhibitors, indicated that the inhibition of a COX-2 with a moderate dose of a selective COX-2 inhibitor did not induce clinically sufficient regression of adenomas in patients with FAP in a limited (6-month) medication period.

Is histological investigation of polyps always necessary?

To assess whether polyp histological type can be predicted by patient characteristics and endoscopic polyp findings. 1681 polyps in 494 patients were categorized as advanced adenomas (villous component or severe dysplasia or early cancer) or insignificant polyps. Chi-squared tests were used to analyze whether polyp histological type could be predicted based on patient age (< 60 vs. > or = 60 years), gender, family history of colon polyps or cancer, presence of anemia, polyp size (< or = 5 mm vs. > 10 mm), and location (left- vs. right-sided). Insignificant polyp histology (n = 1337) correlated with patient age < 60 years (P = 0.0026), lack of anemia (P< 0.0001), polyp size < or = 5 mm (P < 0.0001), and right-sided location (P= 0.0058). Stepwise inclusion of these parameters demonstrated that the association of a < or = 5 mm right-sided polyp in a patient < 60 years yielded the highest combined predictive value (96.2%) for an insignificant polyp. Conversely, age > or = 60 years, presence of anemia, polyp size > 10 mm, or left-sided location, as single or combined parameters, demonstrated a maximum predictive value of only 75.4% for an advanced adenoma. A small right-sided polyp in a young patient is associated with a small risk (3.8 %) for advanced adenomatous tissue, indicating that histological investigation of such a polyp might not always be necessary. However, the recent recognition of flat adenomas and "mini" de novo colon carcinomas in the European population also may limit the usefulness of small polyp diameters in the exclusion of severe polyp histology.

Reproductive Strategies of Modular Organisms: Comparative Studies of Reef‐ Building Corals

The fecundity of clonal animals and plants is determined by the number of gravid modules (polyps, zooids, shoots, ramets) and their reproductive output. We examined the fecundity of modules (polyps) and colonies of six reef—building corals (Acropora hyacinthus, A. nana, A. gemmifera, A. millepora, Goniastrea retiformis, and Stylophora postillata) to explore how modularity influences reproductive strategies and the evolution of life histories in clonal animals. In unitary, aclonal organisms, fecundity often reaches a plateau or declines in old age. In contrast, we found that fecundity of colonies was indeterminate because vegetative growth can lead to an indefinite number of repeated, reproductive modules. However, colony fecundity was not a simple linear function of the number of modules. The species ranking of polyp fecundities (G. retiformis &gt; the Acropora species &gt; S. pistillata) was very different from the ranks of size—specific colony fecundities (A. hyacinthus, A. millepora, A. gemmifera &gt; A. nana and G. retiformis). Colony fecundity for small S. pistillata was the lowest of all, but large colonies were more fecund than any of the other species at a comparable colony size (despite Stylophora having the lowest polyp fecundity). This contrast highlights clearly the effects of modularity on the reproductive biology and life histories of clonal organisms. The volume of eggs and testes, and the number of eggs and testes per polyp varied greatly among species (20—, 13—, 17—, and 3—fold, respectively). Egg volume was smallest for S. pistillata (the only brooder in the study) and for G. retiformis (which also had the most eggs per polyp, indicating a trade—off between egg size and number). The total reproductive volume per polyp (egg and testes combined) varied three—fold among the six species, and was correlated with a similar range of polyp diameters. In some cases, components of polyp fecundity depended on colony size; egg size in A. hyacinthus and A. nana and the number of planulae per polyp in S. pistillata increased by two— to fourfold with a one to two order of magnitude change in colony size. However, egg size was constant for the other species. Similarly, colony size had no effect on egg or testes number per polyp or testes volume per polyp for any species. We also found striking differences in sex allocation, which may relate to the fertilization biology of these hermaphroditic species. The ratio of total egg volume to testes volume per polyp varied fivefold, and was lowest for S. pistillata (a brooder) and G. retiformis (which produced the most and smallest eggs). The ratio increased with colony size for all species, especially A. hyacinthus. An early investment predominantly in testes allows sex to commence without the initial expense of egg production, perhaps so that colony growth can continue to a larger, safer size. All species had a characteristic colony size at maturation, which varied ninefold among taxa, corresponding to a minimum puberty age of 1—3 yr. This is the first comparative study to simultaneously measure male and female function in a range of clonal animals.