Increased expression of a putative adenoma-associated antigen in pre-colonoscopic effluent of patients with colorectal cancer

Polyps as biomarkers for colorectal neoplasia

“…Often, in the patient with cancer, this expression was ectopic and sometimes incompatible with the patient's usual antigenic determinants as in the case of blood group antigens (6). The finding of a microscopic equivalent of an adenoma-dysplasia, the aberrant crypt focus, within normal-appearing mucosa suggested that there was a basis for a "field" theory of carcinogenesis (7) and that the study of antigens of the more easily recognizable adenomatous polyps may facilitate our understanding of colorectal cancer (CRC). *Patients with juvenile polyps are a heterogenous group, only some of those affected manifest this germ line aberration.…”

“…While a great deal of work with tissue antigens included such polyp tissues (8), surprisingly little effort was directed at raising antibodies specific to adenomas (7,9).…”

“…In 1990 we reported the generation of monoclonal antibodies against constituents of tubular adenomas in an attempt to define the earliest possible manifestation of an adenoma associated antigen (7). Part of the hybridoma screening strategy was to exclude common oncofetal and other cancer antigens.…”

Rectal Effluent as a Research Tool

“…Reactivity with a monoclonal antibody generated from mice that had had been exposed to human adenoma tissue, known as ''Adnab-9,'' has been tested in WGLF [52,53] and found to react with a significantly higher percentage of patients at high risk for colorectal cancer (CRC) than controls [54]; however, it was also elevated in the feces of untreated celiac disease patients [55] and therefore may not be specific to cancer. Hemoglobin levels are also higher in WGLF of patients with CRC, diverticulosis, and IBS than in control patient which is not unexpected [56].…”

Stool Markers for Colorectal Cancer Screening: Future Considerations

“…For nearly a century, exfoliated cells have been recovered from the gastrointestinal lu men to diagnose cancer [51,52], During the 1950s, several studies demonstrated that cy tologic examination of the colorectal effluent solution after enema lavage approached the sensitivity and specificity of colon X-ray for cancer detection [53][54][55], More recently, sev eral studies in selected patients have shown that simple cytologic inspection of effluent following enema or oral lavage purgation al lowed nearly 100% sensitivity for colorectal cancer with 95-100% specificity [56][57][58][59][60][61], Such cytologic detection was equally effective with proximal and distal cancer. While the discomfort and inconvenience of a colonic lavage and the cost of examination by a cytologist render this approach impractical for mass screening, lavage cytology has clearly demonstrated the discriminating value of ex foliated cells.…”