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Peutz−Jeghers Syndrome
Published in Dongyou Liu, Handbook of Tumor Syndromes, 2020
PJS polyps typically emerge within the first few years of life in the small intestine (typically jejunum followed by ileum and duodenum, 64% of cases), colon (63%), stomach (48%), and rectum (32%), but not esophagus (Figure 22.2) [9]. Sometimes, polyps may occur in the renal pelvis, urinary bladder, ureters, gallbladder, lungs, and nostrils. Showing erratic growth, PJS polyps may remain the same size for many years, and some polyps may regress or autoamputate spontaneously. While their potential for malignant transformation remains to be determined, PJS polyps are responsible for small intestinal obstruction and intussusception (42.8% of cases, due mainly to polyps of ≥1 .5 cm in diameter, usually between the ages of 6 and 18 years), abdominal pain due to infarction (23%), hematochezia (rectal bleeding) due to ulceration (13.5%), prolapse of colonic polyp (7%), nausea, vomiting, and secondary iron deficiency/anemia (typically occurring in the second and third decades of life) [10–12].
Micronutrients in Cancer Prevention
Published in Kedar N. Prasad, Micronutrients in Health and Disease, 2019
The third stage of carcinogenesis involves the induction of random mutations in the hyperplastic cells. Most of such mutations play no role in converting hyperplastic cells to cancer cells; however, when mutations occur in specific cellular genes, oncogenes, or antioncogenes, hyperplastic cells become cancerous. This is well demonstrated in colon polyps and female breast and ovarian cysts, which remain noncancerous for a long time, but if not removed, become cancerous. Because mutation occurs randomly, the colon polyp may carry defects in more than one oncogene. The multiple, heterogeneous foci of cancer cells found in the colon polyps are not necessarily clonal with respect to a given oncogene. This heterogeneity may be the reason why, in spite of extensive research in molecular carcinogenesis, it has not been possible to establish any direct relationship between the presence of one defective oncogene or other cellular genes and tumor type or tumor behavior, although some associations between oncogene or anti-oncogene and tumor behavior have been documented.
The Role of the Clinical Laboratory in Nutritional Assessment
Published in Aruna Bakhru, Nutrition and Integrative Medicine, 2018
A common cause of iron deficiency in older adults is colorectal polyps and cancer. Fecal immunochemical tests (FIT) are used to identify blood in the lower gastrointestinal tract that requires further evaluation including potentially a colonoscopy. Often there is a benign colonic polyp or cancer that is bleeding into the colon. With sufficient bleeding, the body's ability to produce enough new red blood cells falls behind the loss of blood and iron deficiency anemia may develop.
Short-term effect of a negative colonoscopy in patients with functional constipation
Published in Baylor University Medical Center Proceedings, 2019
Qi-Shan Zeng, Juliana Yang, Chun-Cheng Wu, Lian-Song Ye, Wei Liu, Hong-Ze Zeng, Shan Jiang, Yu-Hang Zhang, Xiang-Lei Yuan, Xian-Hui Zeng, Yong-Hong Luo, Bing Hu
A total of 75 patients with chronic constipation were enrolled, with written informed consent provided for all patients. Sixty-nine patients were eligible for enrollment. Six patients were ineligible; among them, two had colon cancer and four had colonic polyp/adenoma with diameter >6 mm. Unfortunately, among the 69 patients, 8 patients were lost to follow-up after their colonoscopy. Finally, 61 patients with functional constipation completed the pre- and postcolonoscopy questionnaires. Among the 61 patients, 20 patients did not take any medicines for constipation before and after colonoscopy (group 1), 16 patients took the same medicine before and after colonoscopy (group 2), 9 patients took medicine before colonoscopy but no medicine after colonoscopy (group 3), 9 patients took different medicines before and after colonoscopy (group 4), and 7 patients did not take medicine before colonoscopy but did after colonoscopy (group 5). Therefore, only 45 patients (groups 1, 2, and 3) were included in the statistical analysis. Demographic features of this patient cohort are shown in Table 1.
Development and Characterization of a Novel Congenic Rat Strain for Obesity and Cancer Research
Published in Nutrition and Cancer, 2018
Ann Marie O'Neill, Erin A. Gillaspie, Christine M. Burrington, Darin T. Lynch, Robert T. Dauchy, David E. Blask, Paul C. Tirrell, Brian A. Reis, Melissa J. Horsman, Michael W. Greene
Whilst the epidemiological evidence linking obesity and human cancer is strong, the mechanism linking obesity and cancer is not clear. The data linking rodent colon cancer with obesity has not been entirely consistent with the human epidemiological data. For example, chemically-induced colorectal carcinogenesis in high fat diet fed mice resulted in increased colon polyp formation (6) but less colorectal lesions (7) in obese mice compared to lean mice. Mixed results in murine colon cancer tumor growth have also been reported: diet-induced obesity increased growth of murine carcinoma-38 colon cancer in a mixed murine background and in C57Bl/6NCr mice (8) but not in C57Bl/6 mice (9). More recent studies have shown that colon cancer xenograft growth is enhanced in severe combined immune deficiency (SCID) and BALB/c mice fed a high fat diet (10,11). However, it is difficult to disassociate the obesity effects from the potential diet effects in these recent studies. Furthermore, although the evidence linking obesity and colon cancer is strong, the paucity of suitable rodent/animal models in which to study human colon cancer growth remains an obstacle to unraveling the underlying molecular mechanisms responsible and evaluating cancer therapeutics in the context of obesity and associated pathophysiology.
Advances in endoscopy for colorectal polyp detection and classification
Published in Baylor University Medical Center Proceedings, 2020
Vijeta Pamudurthy, Nayna Lodhia, Vani J. A. Konda
Autofluorescence spectroscopy uses the principle that certain molecules of the gastrointestinal cells called fluorophores emit light when stimulated by light. The modification in biochemical composition of dysplastic tissue can be detected by these techniques.48,49 A novel imaging technology called second harmonic generation has the ability to evaluate the amount of extracellular matrix collagen protein and its alignment. It can differentiate malignant from nonmalignant colonic polyp tissue with high sensitivity and specificity and can also distinguish high-grade dysplasia and malignant lesions in an objective, numeric fashion, which makes it a very promising technique to use for early CRC detection.50