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General surgery
Published in Kaji Sritharan, Jonathan Rohrer, Alexandra C Rankin, Sachi Sivananthan, Essential Notes for Medical and Surgical Finals, 2021
Kaji Sritharan, Jonathan Rohrer, Alexandra C Rankin, Sachi Sivananthan
Can be neoplastic or non-neoplastic, i.e. hyperplastic, harmartomatous polyps. Neoplastic polyps can be morphologically classified as either sessile or pedunculated; three histological types: Tubular adenoma: most common benign polyp; <5% malignant; often pedunculated; diameter usually <2.5 cm. Risk of malignant change increases with increasing sizeVillous adenoma: higher likelihood of malignant change (» 40%); usually sessile and largeTubulovillous adenoma: features of both; intermediate risk of malignant change
Colorectal Cancer
Published in Pat Price, Karol Sikora, Treatment of Cancer, 2020
Normal large-bowel epithelium has a turnover of approximately 6 days. The proliferative compartment is restricted to the lower third of the crypt. As cells divide and migrate from this zone, they differentiate and lose the ability to divide. In adenomatous lesions, the proliferative compartment enlarges, so the entire crypt and surface may be involved, which, combined with increased longevity of the cells/reduced cell death, results in crypt extension and branching, producing a tubular architecture. In lesions with mesenchymal proliferation, a villous architecture results in a tubulovillous adenoma. A polyp is a protrusion of a circumscribed lesion into a hollow viscus.
Epidemiology of colorectal cancer
Published in A. R. Genazzani, Hormone Replacement Therapy and Cancer, 2020
There is now a good deal of evidence supporting infrequent sigmoidoscopy as a potentially effective screening modality for colorectal cancer. Impressive reductions in rectal cancer and cancer of the proximal colon have been reported from demonstration studies: 85% reduction in 21 000 subjects undergoing ‘clearing’ proctosigmoidoscopy followed by annual proctosigmoidoscopy with removal of all lesions detected35; 70% reduction in risk of colorectal cancer for 10 years following sigmoidoscopy36; 80% reduction in incidence following examination performed mostly by flexible sigmoidoscopy37; and an 85% reduction of rectal cancers achieved by the removal of adenomas38. Although the initial examination may be expensive, there is an advantage that polyps may be removed at the time of the initial procedure and no follow-up visits will be required. Detection of polyps by sigmoidoscopy may indicate the need to explore the more remote and less accessible part of the colon using colonoscopy. Patients with a villous or tubulovillous adenoma in the distal colon are at increased risk of colon cancer in the proximal colon39. However, about half the patients with advanced neoplasia in the proximal part of the colon do not have distal lesions, and therefore would not benefit from screening with sigmoidoscopy40. Use of a 65-cm flexible sigmoidoscope is more effective in detecting polyps than rigid versions.
Investigate the role of PIK3CA gene expression in colorectal polyp development
Published in Egyptian Journal of Basic and Applied Sciences, 2023
Ameer Ali Imarah, Rana Ahmed Najm, Haider Ali Alnaji, Saleem Khteer Al-Hadraawy, Abbas F. Almulla, Hussein Raof Al-Gazali
The majority of histological types in this study was tubular adenoma (n = 53), and only 15 cases were tubulovillous adenoma (Figure 5). Histological type-tubular adenoma and results of PIK staining among the site of the polyp are shown in Figure 6. In the right colon, the number of cases with tubular adenoma given negative for PIK staining was significantly higher than those given positive. The positive cases were significantly higher in the left colon than the negative ones. All cases in the rectum were diagnosed as tubular adenoma, and the number of cases given positive was roughly equal to those given negative. Concerning tubulovillous, Figure 7 shows no significant differences between positive and negative cases in both the left and right colon. No cases in the rectum were diagnosed as tubulovillous adenoma, Figures 7–11.
Rapidly progressive dyspnea in gastrointestinal stromal tumor (GIST) with imatinib cardiac toxicity
Published in Journal of Community Hospital Internal Medicine Perspectives, 2018
Adnan Asif Parvez Ghias, Shahzeem Bhayani, David J. Gemmel, Sudershan K. Garg
A 73-year-old African-American male with a history of benign hypertension presented with a 3-day history of dyspnea, cough, and fever. He also complained of weight loss, malaise, cough, and fatigue. During admission, imaging showed prostatic hyperplasia, midline retroperitoneal adenopathy, multifocal hypodense hepatic lesions, periportal adenopathy, and gastric wall thickening on abdominal and pelvic CT scan (Figure 1). He underwent esophago-gastro-duodenoscopy and biopsy of a large antral mass, which returned negative for malignancy. Diagnostic laparoscopy with triplicate core biopsies returned positive for GIST with spindle cell type differentiation (Figure 2). The patient was started on neoadjuvant imatinib 400 mg daily to reduce tumor size prior to possible surgical resection. Colonoscopy also revealed pan diverticulosis and a proximal rectal polyp, which was tubulovillous adenoma and superficial adenocarcinoma on pathological report.
Endoscopic papillectomy or pancreaticoduodenectomy for ampullary lesions: a single center retrospective cohort study
Published in Scandinavian Journal of Gastroenterology, 2022
Steffen Seyfried, Georg Kähler, Sebastian Belle, Daniela Hirsch, Christoph Reißfelder, Nuh Rahbari, Julia Hardt
The histopathological examination of the specimen showed that the resected lesion was a tubulovillous adenoma in 26 patients (61.9%) in the EP cohort, whereas 37 patients (86.0%) in the PD cohort had adenocarcinomas. Lesions in the PD cohort were significantly larger than in the EP cohort. However, the completeness of resection did not differ between both cohorts and there was only one single patient with microscopic residual tumor (R1) in the EP cohort. All histopathological and tumor characteristics are shown in Table 3.