Epidemiological studies suggest that nonsteroidal anti-inflammatory agents decrease the risk of colorectal cancer. This is believed to be mediated, at least in part, by inhibition of cyclooxygenase (COX) activity. There are two COX isoenzymes, namely the constitutively expressed COX-1 and the inducible COX-2. COX-2 is overexpressed in adenomas and colorectal cancers, and COX-2-specific inhibito...

Considerable evidence exists to support the use of vitamin D to prevent and/or treat colorectal cancer. However, the routine use of bioactive vitamin D, 1,25-dihydroxyvitamin D3, is limited by the side effect of toxic hypercalcemia. Recent studies, however, suggest that colonic epithelial cells express 25-hydroxyvitamin D3-1alpha-hydroxylase, an enzyme that converts nontoxic pro-vitamin D, 25-h...

AIM To identify the prevalence, and clinical and pathologic characteristic of colonic polyps among Iranian patients undergoing a comprehensive colonoscopy, and determine the polyp detection rate (PDR) and adenoma detection rate (ADR). METHODS In this cross-sectional study, demographics and epidemiologic characteristics of 531 persons who underwent colonoscopies between 2014 and 2015 at Mehrad...

BACKGROUND Familial adenomatous polyposis usually results in colonic polyposis with hundreds to thousands of polyps, congenital hypertrophy of the retinal pigment epithelium (CHRPE), and variable extracolonic features. Recent reports indicate that patients with distal mutations between codons 1445 and 1578 do not express CHRPE and have a high incidence of desmoid tumours. PATIENTS The family ...

The hamartomatous polyps in Peutz-Jeghers syndrome may have malignant potential. To differentiate between hamartomatous and adenomas polyps, vascular characterization can be assessed using noninvasive procedures, such as contrast-enhanced ultrasound (CEUS). The neo-angiogenic characteristics of colorectal adenomas and carcinomas are expressed as an anarchic vascular pattern observed on CEUS. Us...

OBJECTIVES To prospectively examine the association between human papilloma virus (HPV) colonization of the colonic mucosa and the development of colorectal polyps (CRPs), and colorectal cancer (CRC) in Saudi Arabia. METHODS A case control study was performed between January 2013 and December 2014. All eligible patients underwent standard diagnostic colonoscopy. Patients with polyps or colore...

We present a thirty five years old woman with a family history of Peutz-Jeghers syndrome (PJS) (sister, brother and father) and a four-month history of progressive and constant right iliac fossa pain accompanied by weight loss of 5 kg. The patient does not refer nausea, vomiting or fever. The abdomen was soft, painless, without other signs of peritoneal irritation or palpable masses. In the res...

BACKGROUND & AIMS Specific mutations in the adenomatous polyposis coli (APC) gene can lead to an attenuated form of familial adenomatous polyposis (AFAP). Although AFAP mutation carriers have a 69% risk of colorectal cancer by age 80, clinical recognition remains a challenge in some cases because they present with few colonic adenomas and are difficult to distinguish clinically from patients wi...

Adenomas are the precursors of most colorectal cancers. Hyperplastic polyps have been linked to the subset of colorectal cancers showing DNA microsatellite instability, but little is known of their underlying genetic etiology. Using a strategy that isolates differentially methylated sequences from hyperplastic polyps and normal mucosa, we identified a 370-bp sequence containing the 5' untransla...

PURPOSE Recent data support the hypothesis that the inducible isoform of cyclooxygenase (COX-2) plays a role in the early stages of colonic carcinogenesis and that nonsteroidal anti-inflammatory drugs (NSAIDs) retard the development of colon cancer by modulating COX-2. However, the cell types responsible for producing COX-2 in colorectal adenomas remain a subject of controversy. EXPERIMENTAL ...