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An increasing burden on health care resources has resulted in a backlog of individuals requiring colonoscopy, with delays in surveillance possibly detrimental for individuals at increased risk of colorectal cancer (CRC). This study investigated the use of a 2-sample fecal immunochemical test (FIT) to establish those most likely to have advanced neoplasia (AN) and in need of prioritized surveillance colonoscopy. This was a prospective study conducted in the tertiary care setting. Participants completed a 2-sample FIT (OC-Sensor, Eiken Chemical Company) within 90 days of surveillance colonoscopy. The sensitivity of FIT for detection of AN (CRC or advanced adenoma) in moderate- and high-risk individuals was determined at fecal hemoglobin thresholds between 2 and 80 μg/g feces. A total of 766 patients were included (median age, 66.1 years [interquartile range, 58.1–72.9]; 49.9% male), with AN detected in 8.6% (66/766, including 5 CRC). For moderate-risk individuals (with prior history of adenoma or a significant family history of CRC), sensitivity of FIT for AN ranged from 73.5% at 2 μg/g feces, to 10.2% at 80 μg/g feces. For high-risk conditions (confirmed/suspected genetic syndromes or prior CRC), sensitivity of FIT was similar, ranging from 70.6% at the lowest positivity threshold of 2 μg/g feces, to 11.8% at 80 μg/g feces. Independent variables in the whole cohort for association with detection of AN at surveillance colonoscopy were age (odds ratio, 1.03; 95% confidence interval, 1.00–1.06) and FIT hemoglobin result ≥10 μg/g feces (odds ratio, 1.81; 95% confidence interval, 1.04–3.16). The use of FIT before surveillance colonoscopy provides clinicians with insights into the risk of AN. This raises the possibility of a method to triage individuals, facilitating the more efficient management of endoscopic resources. [ABSTRACT FROM AUTHOR]

In above-average-risk individuals undergoing colonoscopy-based surveillance for colorectal cancer (CRC), screening with fecal immunochemical tests (FIT) between colonoscopies might facilitate personalization of surveillance intervals. Because a negative FIT is associated with a reduced risk for CRC, we examined the relationship between number of rounds of negative FIT and risk for advanced neoplasia in individuals undergoing surveillance colonoscopy. We conducted a retrospective cohort study on 4021 surveillance intervals in 3369 individuals (50–74 years), who had completed a 2-sample FIT between colonoscopies, from 1 to 4 rounds at 1–2 yearly intervals, each with a negative result (<20 μg hemoglobin/g feces). Incidence of advanced neoplasia (CRC or advanced adenoma) was determined at the follow-up colonoscopy. Competing-risk regression was used to assess the association between multiple negative FIT results and the risk of advanced neoplasia within 2 years. The incidence of advanced neoplasia in the cohort was 9.9% and decreased with increasing numbers of rounds of negative FIT results: 11.1% after 1 negative FIT to 5.7% after 4 negative FIT. The risk of advanced neoplasia was significantly lower in participants with 3 (subdistribution hazard ratio, 0.50; 95% confidence interval, 0.24–0.97) and 4 (subdistribution hazard ratio, 0.33; 95% confidence interval, 0.15–0.73) rounds of negative FIT compared with only 1 negative FIT. There was a low risk of advanced neoplasia after multiple rounds of negative FIT in above-average-risk people undergoing surveillance with no neoplasia or nonadvanced adenoma at prior colonoscopy. This supports the use of interval FIT to personalize surveillance by lengthening colonoscopy intervals following multiple negative FIT results. [Display omitted] [ABSTRACT FROM AUTHOR]

Zinc deficiency is a major cause of childhood morbidity and mortality. The WHO/UNICEF strategy for zinc supplementation as adjunctive therapy for diarrhea is poorly implemented. A conference of experts in zinc nutrition and gastrointestinal disorders was convened to consider approaches that might complement the current recommendation and what research was needed to develop these approaches. Several key points were identified. The design of novel zinc interventions would be facilitated by a better understanding of how disturbed gut function, such as environmental (or tropical) enteropathy, affects zinc absorption, losses, and homeostasis. Because only 10% of zinc stores are able to be rapidly turned over, and appear to be rapidly depleted by acute intestinal illness, they are probably best maintained by complementary regular supplementation in a primary prevention strategy rather than secondary prevention triggered by acute diarrhea. The assessment of zinc status is challenging and complex without simple, validated measures to facilitate field testing of novel interventions. Zinc bioavailability may be a crucial factor in the success of primary prevention strategies, and a range of options, all still inadequately explored, might be valuable in improving zinc nutrition. Some therapeutic actions of zinc on diarrhea seem attributable to pharmacologic effects, whereas others are related to the reversal of deficiency (ie, nutritional). The distinction between these 2 mechanisms cannot be clarified given the insensitivity of serum zinc to identify subclinical deficiency states. Why zinc seems to be less effective than expected at all ages, and ineffective for secondary prevention of diarrhea in children <12 mo of age, remains unclear. It was concluded that a reframing of the current recommendation is warranted with consideration of how to better optimize and deliver zinc and whether to provide a complementary public health primary prevention zinc strategy. This requires careful consideration of the zinc product to be used as well as strategies for its delivery. [ABSTRACT FROM AUTHOR]

Background & Aims: Rapidly progressing or missed lesions can reduce the effectiveness of colonoscopy-based colorectal cancer surveillance programs. We investigated whether giving fecal immunochemical tests (FITs) for hemoglobin between surveillance colonoscopies resulted in earlier detection of neoplasia. Methods: The study included 1736 patients with a family history or past neoplasia; they received at least 2 colonoscopy examinations and were followed for a total of 8863 years. Patients were excluded from the study if they had genetic syndromes, colorectal surgery, or inflammatory bowel disease. An FIT was offered yearly, in the interval between colonoscopies; if results were positive, the colonoscopy was performed earlier than scheduled. Results: Among the 1071 asymptomatic subjects (61%) who received at least 1 FIT, the test detected 12 of 14 cancers (86% sensitivity) and 60 of 96 (63%) advanced adenomas. In patients with positive results from the FIT, the diagnosis of cancer was made 25 months (median) earlier and diagnosis of advanced adenoma 24 months earlier. Patients who had repeated negative results from FIT had an almost 2-fold decrease in risk for cancer and advanced adenoma compared with patients who were not tested (5.5% vs 10.1%, respectively, P = .0004). The most advanced stages of neoplasia, observed across the continuum from nonadvanced adenoma to late-stage cancer, were associated with age (increased with age), sex (increased in males), and FIT result. The probability of most advanced neoplastic stage was lowest among those with a negative result from the FIT (odds ratio, 0.68; P < .001). Conclusions: Interval examinations using the FIT detected neoplasias sooner than scheduled surveillances. Subjects with negative results from the FIT had the lowest risk for the most advanced stage of neoplasia. Interval FIT analyses can be used to detect missed or rapidly developing lesions in surveillance programs. [ABSTRACT FROM AUTHOR]

Recent reports suggest that combinations of prebiotics and probiotics may be protective against colorectal cancer. We examined in rats the effects of probiotic bacteria, resistant starch (RS), and their interaction on luminal and epithelial events of relevance to the development of colorectal cancer. Lyophilized cultures (1 × 1010 cfu/g) of Lactobacillus acidophilus and/or Bifidobacterium lactis were added at a concentration of 1% by weight to a semipurified diet containing either low-RS (no supplemented RS) or moderate-RS (10% Hi-maize®) and fed to male Sprague­Dawley rats for 4 wk. Experimental end-points included cecal bacterial enumeration, fecal and cecal pH, SCFA levels, cell proliferation, and the acute apoptotic response to a genotoxic carcinogen (AARGC; measured 6 h after a single azoxymethane injection). A significant interaction between dietary RS and supplemental bacteria was observed for the AARGC in the colon and fecal pH (P < 0.01). Rats fed the moderate-RS diet in combination with B. lactis had a significantly greater AARGC in the colon than those fed that diet without B. lactis. Fecal pH was elevated in the moderate-RS fed rats supplemented with bacteria. The moderate-RS diet increased cell proliferation and crypt column height (P < 0.001) compared with the low-RS diet. SCFA levels and numbers of bifidobacteria and lactobacilli species were also increased (P < 0.001) by the moderate-RS diet, whereas pH levels and total coliforms were lowered (P < 0.001). The synbiotic combination of RS and B. lactis significantly facilitated the apoptotic response to a genotoxic carcinogen in the distal colon of rats. It appears likely that ingested RS acts as a metabolic substrate, thus creating the right conditions for B. lactis to exert its proapoptotic action. Because the synbiotic combination of these agents facilitates the apoptotic response to DNA damage by a cancer initiator in the colon of rats, it warrants further study for its capacity to protect against colorectal cancer. [ABSTRACT FROM AUTHOR]