Small early tubular adenomas and mixed colonic polyps found on screening flexible sigmoidoscopy do not predict proximal neoplasia in males

Differential Labeling by Monoclonal Antibodies Adnab-9 and Anti-?-Defensin 5 Based on the Distribution and Adenomatous Tissue Content of Colonic Polyps

“…It has also been reported that distal or left-sided adenomas appear to have a higher malignant potential than proximal or right-sided adenomas (12). Hyperplastic polyps, on the other hand, are not considered to be neoplastic but the malignant potential of mixed polyps (polyps containing both hyperplastic and adenomatous components) is yet to be definitely determined but in a selected group of male patients we found no increased malignant potential (13). We stained different types of colonic polyps with two monoclonal antibodies, Adnab-9 and anti-α-defensin 5 (AD5), to assess if these polyps differ in their staining characteristics based on their adenomatous content and their colonic distribution.…”

“…Adnab-9 binding has been shown to identify a subpopulation of cells in colonic adenomatous and normal mucosa from colons bearing CRC, but not carcinomatous tissue, some of which resemble Paneth cells (PC) (13)(14)(15)(16). The presence of Adnab-9 staining in nonneoplastic colonic epithelium has been shown to be associated with an increased risk for development of colorectal cancer (13)(14)(15)(16)(17). In addition, Adnab-9 staining has a positive correlation with multiplicity and recurrence of colonic polyps and may be a predictor of future development of dysplastic polyps with recognized malignant potential in these patients (18).…”

Risk of Proximal Colonic Neoplasms in Asymptomatic Adults Older Than 50 Years Found to Have Distal Hyperplastic Polyps on Routine Colorectal Cancer Screening

“…This finding concurs with the conclusions and outcomes of other investigators who have also reported on this topic. [12][13][14][15][16][17] In addition, this analysis demonstrated that there is a significant increase in odds of having a proximal neoplasm found on a routine screening examination if one is a Caucasian man, is a man not taking aspirin or NSAIDs, is of advancing age, has a history of cancer other than CRC, or is a woman actively taking estrogen. With the exception of the latter two variables, these factors too have been documented by other researchers to be associated with neoplasms in the large intestine.…”

“…To date, 13 trials have been conducted on the proposed topic and target population. [4][5][6][7][8][9][10][11][12][13][14][15][16][17] Although the authors of seven [5][6][7][8][9][10][11] of these studies have concluded that distal HPs do predict the presence of SPNs and necessitate colonoscopy, the authors of the remaining six [12][13][14][15][16][17] have reported that no such increased risk exists, thus nullifying the need for colonoscopy. Moreover, beyond these visible discrepancies within the published literature, there are also tangible inconsistencies among the formal recommendations made for patients with distal HPs discovered by screening FS.…”

Prevalence of Proximal Neoplasms Among Asymptomatic Patients According to Distal Colorectal Findings

“…In contrast, 11 studies have reported opposite results [11,12]. A recent study on mixed polyps found no association with proximal neoplasia [19]. In the light of practice guidelines suggesting that hyperplastic polyps are not important [20,21] and the need to consider previous findings in the process of interpreting new data [22] the importance of hyperplastic polyps remains uncertain and must be clarified by further research [12].…”