			Home About us Contact

Tubular Adenoma (tubular + adenoma)

Distribution by Scientific Domains

Medical Sciences	100%

Distribution within Medical Sciences

Gastroenterology & Hepatology	30%
Surgery & Surgical Specialties	15%

Selected Abstracts

Colorectal tumors frequently express phosphorylated mitogen-activated protein kinase

APMIS, Issue 4-5 2004
SUG HYUNG LEE
Mounting evidence suggests that activation of the mitogen-activated protein (MAP) kinase pathway plays an important role in tumorigenesis. MAP kinase/ERK kinase (MEK), a crucial constituent of this pathway, is activated by phosphorylation, and the phosphorylated MEK (pMEK) in turn activates ERK kinase. The expression of pMEK has been described in some human malignancies, but not in primary human colon tumors. In this study, we analyzed the expression of pMEK in 123 colorectal tumors by immunohistochemistry. pMEK was detected either in the cytoplasm (63 cases) or nucleus (40 cases) in 93 of the 123 tumors (76%). Tubular adenomas and villous adenomas also expressed pMEK in 30% and 40% of the tumors, respectively. By contrast, the epithelial cells in the normal colonic mucosa showed no or only weak expression of pMEK in the cytoplasm. Taken together, these results indicate that MEK is frequently phosphorylated in colorectal tumors, and suggest that phosphorylation of MEK may play a role in the development of colorectal tumors. [source]

The significance of the diagnosis of atypia in breast fine-needle aspiration

DIAGNOSTIC CYTOPATHOLOGY, Issue 5 2004
Jennifer C. Lim M.D.
Abstract The diagnosis of atypia in breast fine-needle aspiration (FNA) continues to be an area of debate in cytology practice. The aim of this study was to assess the clinical significance of this term and to evaluate potential morphological criteria, which would determine the patient's outcome. A computer-based search was carried out to retrieve breast FNAs performed between 1990 and 2000 that were diagnosed as atypical. Cases followed by surgical resection were reexamined for the presence of morphological features potentially differentiating benign and malignant lesions. Out of 1,568 breast FNAs, there were 64 cases (4%) with a diagnosis of atypia. Thirty-eight cases had surgical follow-up material that revealed malignancy in 14 cases (37%) and benign lesions in 24 cases (63%). The benign diagnostic categories included fibrocystic change (12/24), fibroadenoma (3/24), tubular adenoma (2/24), and nonspecific findings (7/24). The malignant diagnoses included ductal carcinoma (9/14), lobular carcinoma (3/14), ductal carcinoma in situ (DCIS; 1/14), and tubular carcinoma (1/14). The evaluation of cytological criteria used to differentiate benign from malignant lesions (i.e., cellularity, loss of cohesion, myoepithelial cells, nuclear enlargement, nuclear overlap, prominent nucleoli) revealed significant overlap between benign and malignant cases, particularly in cases of fibroadenoma, tubular adenoma, and proliferative breast disease. The surgical follow-up of four hypocellular cases revealed lobular carcinoma in two cases and ductal carcinoma in the remaining two cases. Our study confirmed that the diagnosis of atypia is clinically significant because it is associated with a high probability of malignancy. No morphological criterion is able to reliably differentiate benign and malignant lesions in cases diagnosed with atypia. Diagnosis of atypia is particularly significant in hypocellular cases. We recommended that breast FNAs with a diagnosis of atypia be evaluated further histologically. Diagn. Cytopathol. 2004;31:285,288. © 2004 Wiley-Liss, Inc. [source]

Endoscopic factors in the diagnosis of colorectal dysplasia in chronic inflammatory bowel disease

INFLAMMATORY BOWEL DISEASES, Issue 5 2005
Murat Toruner MD
Abstract Background: Surveillance colonoscopy in inflammatory bowel diseases (IBDs) is advocated for early diagnosis of neoplasia but is imperfect because some patients develop cancer despite surveillance. We sought to determine if any endoscopic factors during surveillance colonoscopy were associated with the diagnosis of colorectal dysplasia before the development of cancer. Methods: We reviewed the Mayo Clinic endoscopic database and medical records of patients with IBD who underwent surveillance colonoscopy between January 2002 and November 2003. Associations were sought between endoscopic factors and the diagnosis of dysplasia. Among 635 IBD patients, 24 (3.8%) had flat dysplasia and 12 (1.9%) had IBD-related polypoid dysplasia. In 28 patients (4.4%), sporadic tubular adenoma was identified. Colonoscopies in which flat dysplasia was identified varied in duration from 7 to 81 minutes (median, 24.5 min) compared with 3 to 70 minutes (median, 22 min) for those in which dysplasia was not found. Results: Using logistic regression analysis, we found that every additional minute in total colonoscopy time increased the flat dysplasia diagnosis rate by 3.5% (P = 0.0157). There was a significant correlation between median surveillance colonoscopy duration per endoscopist and flat dysplasia diagnosis rate (P = 0.0066). The number of biopsies taken during the procedures with flat dysplasia ranged from 6 to 36 (median, 28) compared with 2 to 54 (median, 25) in those without flat dysplasia. There was no significant effect of biopsy number of dysplasia diagnosis. Conclusions: Our results show that the practice of surveillance colonoscopy varies greatly among endoscopists, and longer procedure duration is significantly associated with the likelihood of dysplasia diagnosis. [source]

Yield from colonoscopic screening in people with a strong family history of common colorectal cancer

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8 2000
Damian J Dowling
Abstract Background and Aims: People with a strong family history of common (so-called ,sporadic') colorectal cancer are generally advised to undergo colonoscopic screening, but the starting age for this is unclear. An audit was performed to study the age-related yield of screening colonoscopy in this risk group. Methods: A prospective audit of the outcome of screening colonoscopy was performed on a cohort of 232 people with a strong family history of common colorectal cancer. All were registrants in a familial bowel cancer service solely because of their family medical history. They had no bowel symptoms and no prior endoscopic investigation of the large bowel. Results: Neoplastic lesions were detected by using colonoscopy in 33 participants. In 27 participants, the major lesion was a small tubular adenoma, four had an advanced adenoma and two had cancer. More neoplastic (P = 0.02) and advanced neoplastic (P = 0.03) lesions were found in those patients aged , 50 years. Only one advanced adenoma was detected in a participant below the age of 50 years. Conclusion: The yield from screening colonoscopy in young people (< 50 years) with a strong family history of common colorectal cancer is low, placing doubt on the need for colonoscopic screening before the age of 50 years. [source]

The utility of flexible sigmoidoscopy after a computerized tomographic colonography revealing only rectosigmoid lesions

ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2008
P. E. YOUNG
Summary Background, Identifying polyps by computerized tomographic colonography typically prompts colonoscopy, increasing its cost, risk and inconvenience. Many polyps are confined to the rectosigmoid and theoretically amenable to resection via flexible sigmoidoscopy. Aim, To determine the prevalence of advanced proximal colonic neoplasia when computerized tomographic colonography reveals only rectosigmoid polyps, and characterize the yield of polypectomy via flexible sigmoidoscopy in such patients. Methods, Subjects underwent computerized tomographic colonography and colonoscopy with segmental unblinding. Patients with only rectosigmoid findings by computerized tomographic colonography were identified retrospectively. Flexible sigmoidoscopy findings were estimated by including lesions distal to the descending/sigmoid colon junction during colonoscopy. Proximal lesions were also reviewed. Advanced lesions were defined as: adenocarcinoma, tubular adenoma >1 cm, ,3 tubular adenomas, tubulovillous histology or high-grade dysplasia. Results, By computerized tomographic colonography, 15% (203 of 1372) had only rectosigmoid polyps. Concomitant lesions in the proximal colon were seen in 32% (64 of 203) during colonoscopy. Advanced proximal neoplasia occurred in 2% (three of 203) with only rectosigmoid polyps on computerized tomographic colonography. Conclusions, Using flexible sigmoidoscopy to follow-up computerized tomographic colonography demonstrating only rectosigmoid polyps would eliminate 15% of subsequent colonoscopies. This strategy carries a small risk of missed proximal advanced neoplasia. This miss rate appears comparable to that of colonoscopy alone. Further study on the cost-effectiveness of this approach is warranted. [source]

Robotic-assisted single-incision laparoscopic partial cecectomy

THE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 3 2010
Madhu Ragupathi
Abstract Background Single-incision laparoscopic surgery is an emerging approach in the field of minimally invasive colon and rectal surgery. This modality utilizes a ,scarless' incision concealed within the umbilicus, and results in improved cosmesis with the potential for reduced trauma, pain and length of hospital stay. However, unique technical challenges have curbed its adaptation. Robotic-assisted technique may help overcome these limitations when applied to the single-incision approach. Methods A robotic-assisted single-incision laparoscopic partial cecectomy was performed using the da Vinci® robot and the GelPOINTÔ access device. Modifications of the robotic set-up were utilized to optimize the technique. The robotic instruments were crossed below the abdominal wall to minimize internal conflict and maximize range of motion. Control of the robotic arms was reassigned on the robotic console to create a more intuitive surgical approach. The robotic camera was rotated and positioned vertically to reduce external conflict and enhance visualization. Results Robotic-assisted single-incision laparoscopic partial cecectomy was performed in a 53 year-old male without complication or need for conversion. The procedure required 120 min with an estimated blood loss of < 50 ml. Pathology revealed a sessile tubular adenoma of the cecum. The length of hospital stay was 2 days and no complications were encountered. The patient returned with a well-healed 2.5 cm incision and no postoperative complications at 6 weeks follow-up. Conclusions With appropriate modifications, robotic-assisted single-incision laparoscopic surgery may be applicable as a minimally invasive modality for partial colectomy. Further studies are warranted to establish the safety, efficacy, benefits, and limits of this technique. Copyright © 2010 John Wiley & Sons, Ltd. [source]

Surgical management of benign duodenal tumours,

ANZ JOURNAL OF SURGERY, Issue 7-8 2010
Ji-Qi Yan
Abstract Background:, While benign duodenal tumours are rare compared with malignant tumours, they comprise a wide variety of pathologies. Despite their diagnostic challenge, the optimal management of benign duodenal tumours remains undefined. We aimed to review the diagnosis and surgical treatment of benign duodenal tumours. Methods:, Records of all patients with post-operative pathological diagnosis of benign duodenal tumour were retrieved. Information on clinical presentations, diagnostic methods, tumour locations, surgical approaches, pathological results and patient outcomes were analysed. Results:, The operative spectrum included local resection in 8 cases, segmental duodenectomy in 1 case, subtotal gastrectomy in 1 case, papilla resection with sphincteroplasty in 3 cases and pancreaticoduodenectomy in 5 cases. The post-operative pathology results indicated 5 cases of adenoma, 2 cases of tubular adenoma, 2 cases of villous adenoma, 2 cases of tubulovillous adenoma, 2 cases of hamartoma and 1 case each of hamartomatous polyp, Brunner's adenoma, adenomyoma, fibromatosis and ectopic pancreas. Post-operatively, one patient died of unrelated disease, one case was lost in follow-up and the remaining patients survived recurrence-free with a good quality of life. Conclusion:, The presentation of benign duodenal tumours is non-specific, with upper abdominal discomfort and upper gastrointestinal bleeding as common symptoms. Surgical resection is the preferable therapeutic choice with satisfactory prognosis. [source]

p16Ink4a is Overexpressed in H. pylori -Associated Gastritis and is Correlated with Increased Epithelial Apoptosis

HELICOBACTER, Issue 1 2003
Haim Shirin
ABSTRACT Background. Cell cycle regulatory proteins may be critical targets during carcinogenesis. We have previously shown that chronic H. pylori infection is associated with decreased expression of the cyclin dependent kinase inhibitor (CDI) p27kip1. Loss of p27kip1 and p16Ink4a (p16) expression, another CDI, has been reported during the progression of gastric tubular adenomas to advanced gastric cancer. The aim of the current study was to examine whether H. pylori infection also affects the expression of p16 in the gastric mucosa of H. pylori- infected patients. Methods. p16 expression was evaluated in gastric antral biopsies by immunohistochemistry in 50 patients with nonulcer dyspepsia (n = 18 uninfected, n = 32 H. pylori infected, 24 by cagA+ strains). Adjacent sections were stained for proliferating epithelial cells (by Ki67) and for apoptotic cells (by TUNEL assay). Results. Both in H. pylori infected and uninfected patients the expression of p16 was higher in the neck and base of the gland than in the foveolar region. Epithelial staining for p16 was increased with H. pylori infection (31.3% vs. 11.1% in the foveolar region, 68.8% vs. 27.8% in the neck and 75% vs. 50% in the glandular base). There was no correlation between the expression of 16 and proliferation but there was a significant positive correlation between apoptosis and 16 immunostaining. Conclusions. The tumor suppressor gene 16 is over expressed in gastric epithelial cells of H. pylori infected patients and this is associated with an increase in apoptosis. These findings suggest a possible role for this cell cycle regulator in the increase in gastric cell turnover that is associated with H. pylori infection. [source]

Advanced colorectal polyps with the molecular and morphological features of serrated polyps and adenomas: concept of a ,fusion' pathway to colorectal cancer

HISTOPATHOLOGY, Issue 2 2006
J R Jass
Aim :,To establish and explain the pattern of molecular signatures across colorectal polyps. Methods and results :,Thirty-two sessile serrated adenomas (SSA), 10 mixed polyps (MP), 15 traditional serrated adenomas (SA), 49 hyperplastic polyps (HP) and 84 adenomas were assessed for mutation of KRAS and BRAF and aberrant expression of p53. The findings were correlated with loss of expression of O-6-methylguanine DNA methyltransferase (MGMT). KRAS mutation occurred more frequently (26.5%) than BRAF mutation (4.8%) in adenomas (P < 0.001) and particularly in adenomas with villous architecture (50%). Loss of expression of MGMT correlated with KRAS mutation in small tubular adenomas (P < 0.04). BRAF mutation was frequent in HPs (67%) and SSAs (81%), while KRAS mutation was infrequent (4% and 3%, respectively). Of MPs and SAs, 72% had either BRAF or KRAS mutation. Aberrant expression of p53 was uncommon overall, but occurred more frequently in MPs and SAs (12%) than adenomas (1%) (P < 0.04) and there was concordant loss of expression of MGMT. Conclusions :,Molecular alterations that are characteristic of the serrated pathway and adenoma,carcinoma sequence can co-occur in a minority of advanced colorectal polyps that then show morphological features of both pathways. These lesions account for only 2% of colorectal polyps, but may be relatively aggressive. [source]

Distinct CpG island methylation profiles and BRAF mutation status in serrated and adenomatous colorectal polyps

INTERNATIONAL JOURNAL OF CANCER, Issue 11 2008
Yong Ho Kim
Abstract A subset of colorectal cancers with CpG island methylator phenotype-high (CIMP-H) is frequently associated with MSI and BRAF V600E mutation. Since limited data are available on different histological types of colorectal polyps, we compared the pattern and the frequency of promoter methylation, CIMP-H, MSI, KRAS and BRAF V600E mutations and the relationship among these molecular parameters and the clinicopathologic characteristics in 110 serrated polyps (48 hyperplastic polyps, 32 sessile serrated adenomas and 30 serrated adenomas) and 32 tubular adenomas using 7 commonly used tumor-associated gene loci. No significant difference in the frequency of overall methylation frequency (86% vs. 100%) and CIMP-H (39% vs. 28%) between serrated polyps and tubular adenomas was observed, but proximally located serrated polyps showed more frequent methylation at 5 of 7 loci examined, and were more likely to be CIMP-H (62% vs. 22%). MGMT methylation was more common in tubular adenomas while MLH1 and HIC1 were more frequently methylated in serrated polyps. BRAF mutation was frequently present in all types of serrated polyps (80%), but was absent in tubular adenomas and was not associated with CIMP or MSI status. These results show comparable frequencies of promoter methylation of tumor-associated genes and CIMP-H, but distinct differences in gene-specific or colonic site-specific methylation profiles occur in serrated polyps and tubular adenomas. BRAF mutation occurs independently of CIMP and MSI in all types of serrated polyps and may serve as a marker of serrated pathway of colorectal carcinogenesis. © 2008 Wiley-Liss, Inc. [source]

The utility of flexible sigmoidoscopy after a computerized tomographic colonography revealing only rectosigmoid lesions

Bottom-up cell proliferation with cyclin A and p27Kip1 expression in ulcerative colitis-associated dysplasia

PATHOLOGY INTERNATIONAL, Issue 1 2006
Tetuo Mikami
To analyze the cell kinetics of ulcerative colitis (UC)-associated dysplasia, cyclin A, cyclin D1, cyclin E, cdk2, cdk4, p21Waf1, and p27Kip1 were immunohistochemically examined, in comparison with sporadic tubular adenomas. Immunohistochemical labeling indices for each marker in formalin-fixed paraffin-embedded tissue sections were assessed in a total of 23 low-grade dysplasias, 27 high-grade dysplasias, and 14 invasive adenocarcinomas associated with UC. For comparison, 21 sporadic tubular adenomas with low-grade dysplasia, 33 with high-grade dysplasia, and 21 invasive adenocarcinomas were also examined. In UC-associated dysplasias, cyclin A and p27Kip1 were located in the lower parts of the crypts and p21Waf1 in the upper regions. In tubular adenomas, cyclin A, cdk4, p27Kip1, and p21Waf1 were all expressed in the upper parts of the crypts. The expression levels of cyclin D1, cyclin E, and cdk2 were low. The cell proliferation zone in UC-associated dysplasia is located towards the bases of the crypts with the strong expression of cyclin A and p27Kip1, in contrast to tubular adenomas, which have their cell proliferation zone in the upper parts of neoplastic crypts. It is considered that tumorigenesis with UC-associated dysplasia is of the bottom-up type, related to altered expression of cyclin A and p27Kip1. [source]