Can the rate and location of sessile serrated polyps be part of colorectal Cancer disparity in African Americans?

BACKGROUND: Up to 30% of colorectal cancers develop through the serrated pathway. African Americans (AAs) suffer a disproportionate burden of colorectal cancer. The aim of this study was to evaluate clinicopathological features of AA patients diagnosed with sessile serrated polyps (SSPs). METHODS: We conducted a retrospective study of all colonoscopies (n = 12,085) performed at Howard University Hospital, from January 1st, 2010 to December 31st, 2015, of which 83% were in AA patients, (n = 10,027). Among AAs, pathology reports confirmed 4070 patients with polyps including 252 with SSPs. Demographic and clinical variables (i.e. sex, age, BMI, anatomic location, clinical symptoms, polyp size, and clinical indications were collected at colonoscopy. RESULTS: In the AA population, the median age was 56 with interquartile range (IQR) of 51 to 62 years, 54% were female, and 48% had a BMI > 30. The most common reason for colonoscopy was screening (53%), whereas the prevalent reasons for diagnostic colonoscopies were changes in bowel habits (18%) and gastrointestinal bleeding (17%). The total number of SSPs among the 252 AA (diagnosed with SSPs) was 338. Of these, 9% (n = 29/338) had some degree of cytological dysplasia, primarily in the ascending colon (n = 6/42, 14%), Transverse colon (n = 2/16, 13%) and rectosigmoid (n = 19/233, 8%). About 24% of patients had more than 2 polyps. Most patients (76%) had distal SSPs (rectal and rectosigmoid), in comparison to 14% of proximal polyps and 10% of bilateral locations. Median SSA/P size for all locations was 0.6 cm. CONCLUSION: The prevalence of SSPs accounts for 6% of all polyps in AA patients and was diagnosed in 2.5% of all colonoscopies (n = 252/10,027), which is higher than Caucasians in the US. SSPs were predominantly located in the left side, as compared to published literature showing the predominance in the right side of the colon. Screening of CRC will have the chance to detect high risk SSA/P in this population.

Robotic Versus Laparoscopic Right Colectomy for Colon Cancer: Analysis of the Initial Simultaneous Learning Curve of a Surgical Fellow.

BACKGROUND: Robotic surgery was introduced to overcome laparoscopic drawbacks. This study aimed to compare the learning curve of robotic-assisted right colectomy (RRC) versus laparoscopic-assisted right colectomy (LRC) for colon cancer with respect to operative times and perioperative outcomes. In addition, the health-related costs associated with both procedures were analyzed and compared. METHODS: Between 2012 and 2015, 30 consecutive patients underwent RRC and 50 patients LRC for colon cancer. All procedures were performed by a surgical fellow novice in minimally invasive colorectal surgery. The operative time and the cumulative sum method were used to evaluate the learning curve of RRC versus LRC. RESULTS: The mean operative times were 200.5 minutes for RRC and 204.1 minutes for LRC (P = .408) and showed a significant decrease over consecutive procedures (P < .0001). The number of cases necessary to identify a drop in the operative time was 16 for RRC and 25 for LRC. RRC procedures were associated with significantly reduced blood loss (P = .012). Two patients (4%) in the LRC group were converted to laparotomy, whereas no conversion was required in the RRC group. Surgery-related costs were significantly more expensive for RRC, but when combined with the hospitalization-related costs, LRC and RRC did not differ (P = .632). CONCLUSIONS: Both robotic and laparoscopic operative times decrease rapidly with practice. However, RRC is associated with a faster learning curve than LRC. The simultaneous development of these two minimally invasive approaches appears to be safe and feasible with acceptable health-related costs.

Prophylactic clipping for the prevention of bleeding following wide-field endoscopic mucosal resection of laterally spreading colorectal lesions: an economic modeling study.

BACKGROUND AND STUDY AIMS: Clinically significant bleeding (CSPEB) is the most common adverse event following endoscopic mucosal resection (EMR) of large sessile and laterally spreading colorectal lesions (LSLs), and is associated with morbidity and resource utilization. CSPEB occurs more frequently with proximal LSLs. Prophylactic clipping of the post-EMR defect may be beneficial in CSPEB prevention. The aim of this study was to determine the cost-effectiveness of a prophylactic clipping strategy. We hypothesized that prophylactic clipping in the proximal colon was cost-effective. PATIENTS AND METHODS: An economic model was applied to outcomes from the Australian Colonic Endoscopic Mucosal Resection (ACE) Study. Clip distances of 3, 5, 8, and 10 mm were analyzed. The cost of treating CSPEB was determined from an independent costing agency. The funds needed to spend (FNS) was the cost incurred in order to prevent one episode of CSPEB. A break-even analysis was performed to determine cost equivalence of the costs of clipping and CSPEB. RESULTS: Outcomes of 1717 LSLs (mean size 35.8 mm; 52.6 % proximal colon) that underwent EMR were analyzed. The overall rate of CSPEB was 6.4 % (proximal 8.9 %; distal 3.7 %). Endoscopic management was required in 45 % of CSPEB episodes. With a clip distance of 3 mm, the expected cost of prophylactic clipping was €â€Š1106 per lesion compared with €â€Š157 per lesion for the expected cost of CSPEB without clipping. At 100 % clipping efficacy, the FNS was €â€Š14 826 (proximal and distal lesions €â€Š9309 and €â€Š29 540, respectively). A clip price of €â€Š10.35 was required for the cost of clipping to offset the cost of CSPEB. CONCLUSIONS: A prophylactic clipping strategy is not cost-effective and at present cannot be justified for all lesions or selectively for lesions in the proximal colon. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01368289).

Assessment of tacrolimus absorption from the human intestinal tract: open-label, randomized, 4-way crossover study.

BACKGROUND: Tacrolimus is an established immunosuppressant used for the prevention and treatment of allograft rejection in solid organ transplantation. An immediate-release oral formulation of tacrolimus has been commercially available since 1994 that is administered orally BID. To improve the compliance and quality of life of transplant patients, a once-daily modified release (MR) formulation is an attractive option. However, to be successful, the drug of interest must be sufficiently well absorbed from the distal region of the gastrointestinal tract. OBJECTIVE: To facilitate the development of an MR formulation, we investigated the absorption of tacrolimus from different regions of the human gastrointestinal tract, proximal and distal small bowels, and ascending colon. METHODS: The study was performed as an open-label, randomized, 4-way crossover design in 6 healthy white male subjects. For each subject, 1 mg (2 mg/mL) of tacrolimus solution in polyethylene glycol 400 was administered to each location in the gastrointestinal tract via a site-specific radiolabeled delivery capsule, which can release tacrolimus solution at specific sites of the gastrointestinal tract. Real-time visualization of capsule location and tacrolimus release at each target site was performed by using γ-scintigraphy. Blood samples were collected to determine tacrolimus levels in the blood. The pharmacokinetic parameters Cmax, Tmax after the capsule activation, AUC0-24, and mean residence time were determined from the concentration-time profiles. RESULTS: Ten healthy male subjects underwent dosing. Six subjects completed all 4 treatments. Three adverse events (mild headache [n = 1], small amount of blood in stool [n = 1], and mild syncopal episode [n = 1]) that were possibly study drug related were reported in 3 different subjects. Tacrolimus was absorbed from not only the small intestine but also from the colonic region of the gastrointestinal tract. Although AUC0-24 values revealed some site-specific absorption tendencies, the mean AUC0-24 values obtained were similar regardless of the location of tacrolimus release from the capsule. CONCLUSIONS: Tacrolimus was absorbed from the duodenum to the colon in these male subjects, although differences were observed in the value of AUC0-24, possibly due to variation in cytochrome P450 3A4 activity in the intestine. Although this study was conducted in small group of healthy fasting men, the present results indicate that tacrolimus is suitable for MR formulation development due to a wide absorption window throughout the intestine in humans.

Adjuvant chemotherapy for stage II right-sided and left-sided colon cancer: analysis of SEER-medicare data.

BACKGROUND: Survival benefit from adjuvant chemotherapy is established for stage III colon cancer; however, uncertainty exists for stage II patients. Tumor heterogeneity, specifically microsatellite instability (MSI), which is more common in right-sided cancers, may be the reason for this observation. We examined the relationship between adjuvant chemotherapy and overall 5-year mortality for stage II colon cancer by location (right- vs left-side) as a surrogate for MSI. METHODS: Using Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we identified Medicare beneficiaries from 1992 to 2005 with AJCC stage II (n = 23,578) and III (n = 17,148) primary adenocarcinoma of the colon who underwent surgery for curative intent. Overall 5-year mortality was examined with Kaplan-Meier survival analysis and Cox proportional hazards regression with propensity score weighting. RESULTS: It was found that 18 % of stage II patients (n = 2941) with right-sided cancer and 22 % (n = 1693) with left-sided cancer received adjuvant chemotherapy. After adjustment, overall 5-year survival benefit from chemotherapy was observed only for stage III patients (right-sided: hazard ratio [HR], 0.64; 95 % CI, 0.59-0.68; p < .001 and left-sided: HR, 0.61; 95 % CI, 0.56-0.68; p < .001). No survival benefit was observed for stage II patients with either right-sided (HR, 0.97; 95 % CI, 0.87-1.09; p = .64) or left-sided cancer (HR, 0.97; 95 % CI, 0.84-1.12; p = .68). CONCLUSIONS: Among Medicare patients with stage II colon cancer, a substantial number receive adjuvant chemotherapy. Adjuvant chemotherapy did not improve overall 5-year survival for either right- or left-sided colon cancers. Our results reinforce existing guidelines and should be considered in treatment algorithms for older adults with stage II colon cancer.

Proximal and distal colorectal cancer resection rates in the United States since widespread screening by colonoscopy.

BACKGROUND & AIMS: Screening decreases colorectal cancer (CRC) incidence and mortality. Colonoscopy has become the most common CRC screening test in the United States, but the degree to which it protects against CRC of the proximal colon is unclear. We examined US trends in rates of resection for proximal vs distal CRC, which reflect CRC incidence, in the context of national CRC screening data, before and since Medicare's 2001 decision to pay for screening colonoscopy. METHODS: We used the Nationwide Inpatient Sample, the largest US all-payer inpatient database, to estimate age-adjusted rates of resection for distal and proximal CRC, from 1993 to 2009, in adults. Temporal trends were analyzed using Joinpoint regression analysis. RESULTS: The rate of resection for distal CRC decreased from 38.7 per 100,000 persons (95% confidence interval [CI], 35.4-42.0) to 23.2 per 100,000 persons (95% CI, 20.9-25.5) from 1993 to 2009, with annual decreases of 1.2% (95% CI, 0.1%-2.3%) from 1993 to 1999, followed by larger annual decreases of 3.8% (95% CI, 3.3%-4.3%) from 1999 to 2009 (P < .001). In contrast, the rate of resection for proximal CRC decreased from 30.0 per 100,000 persons (95% CI, 27.4-32.5) to 22.7 per 100,000 persons (95% CI, 20.6-24.7) from 1993 to 2009, but significant annual decreases of 3.1% (95% CI, 2.3%-4.0%) occurred only after 2002 (P < .001). Rates of resection for CRC decreased for adults ages 50 years and older, but increased for younger adults. CONCLUSIONS: These findings support the hypothesis that population-level decreases in rates of resection for distal CRC are associated with screening, in general, and that implementation of screening colonoscopy, specifically, might be an important factor that contributes to population-level decreases in rates of resection for proximal CRC.

Assessment of levetiracetam bioavailability from targeted sites in the human intestine using remotely activated capsules and gamma scintigraphy: Open-label, single-dose, randomized, four-way crossover study in healthy male volunteers.

BACKGROUND: Levetiracetam is a broad-spectrum antiepileptic drug that binds to synaptic vesicle protein SV2A. Levetiracetam is indicated in the adjunctive treatment of partial-onset seizures, myoclonic seizures, and generalized tonic-clonic seizures. It is also approved in Europe as monotherapy for newly diagnosed partial-onset seizures. A Phase I clinical pharmacology trial was conducted during preregistration clinical development to better understand the regional gastrointestinal (GI) absorption of levetiracetam. OBJECTIVE: This study evaluated the relative bioavailability of levetiracetam in various regions of the GI tract using a noninvasive, remote-controlled capsule device providing targeted drug delivery, relative to that after oral administration, and explored the drug's absorption characteristics in healthy volunteers. METHODS: Pharmacokinetic data were obtained from healthy men aged 18 to 65 years in an open-label, single-dose, randomized, 4-way crossover study. Treatments included levetiracetam 250 mg administered as an immediate-release tablet and capsule delivery of 250 mg drug substance (levetiracetam powder without excipients) to the proximal small bowel, distal small bowel, and ascending colon. The location of the capsule in the GI tract was monitored using γ-scintigraphic imaging. Blood samples for plasma levetiracetam concentration were collected before dosing; at 10, 20, 30, and 45 minutes; and at 1, 1.5, 2, 3, 6, 9, 12, 16, 20, and 24 hours after tablet intake or after capsule activation. Pharmacokinetic parameters C(max), T(max), AUC0₋(last), AUC0₋(∞) and t(½) were calculated using noncompartmental methods. Tolerability was determined using clinical assessment, monitoring of vital signs, laboratory analysis, and interviews with the volunteers regarding adverse events. RESULTS: Nine healthy men, 7 whites and 2 Asians, were enrolled (mean [SD] age, 31 [14] years; weight, 77 [5] kg; height, 176 [6] cm). Six volunteers completed all 4 treatments. Seven adverse events (headache [3], lethargy [2], tachycardia [1], and contusion [1]) were reported in 5 volunteers, but only 2 (headache and lethargy) were judged by the investigator to be possibly drug related. The geometric mean (%CV) AUC(0-last) values of levetiracetam delivered in the proximal small bowel, distal small bowel, ascending colon, and stomach (oral tablet) were 58.2 (9.3%), 59.6 (8.9%), 51.5 (12.0%), and 59.0 (7.4%) µg · h/mL, respectively. Values for bioavailability in the proximal small bowel, distal small bowel, and ascending colon relative to the tablet were 98.5% (95% CI, 89.7%-108.2%), 100.8% (95% CI, 91.4%-111.1%), and 87.1% (95% CI, 77.9%-97.5%). CONCLUSION: After delivery in the proximal small bowel, distal small bowel, or ascending colon, the systemic bioavailability of levetiracetam (AUC), but not C(max) and T(max), appeared comparable to that after oral administration and thus appeared site independent in this small group of healthy fasting men.

Assessment of lumiracoxib bioavailability from targeted sites in the human intestine using remotely activated capsules and gamma scintigraphy.

PURPOSE: To determine the bioavailability and pharmacokinetic profile of lumiracoxib from different sites in the gastrointestinal tract. METHODS: Subjects (11 healthy adult males) were randomized to receive a 100 mg lumiracoxib dose, via a site-specific radiolabeled delivery capsule, to the stomach (internal reference), proximal small bowel, distal small bowel, or ascending colon. Gamma scintigraphy was used for real-time visualization of capsule location, and a radiofrequency signal was used to activate capsules at target site. RESULTS: Ten subjects completed the study. The mean capsule activation times for the stomach, proximal small bowel, distal small bowel, and ascending colon were 0.22, 1.52, 3.43, and 11.46 h post dose, respectively. Lumiracoxib was well absorbed from the proximal and distal small bowel, with AUC(0-infinity) ratios 104% (86, 127)% and 110% (89, 136)%, respectively. The highest Cmax (2413 ng/ml) and AUC(0-infinity) for lumiracoxib were in the distal small bowel (6842 ng x h/ml). Effective absorption was observed from the ascending colon, with an AUC(0-infinity) ratio of 85% (69, 104)% vs. the reference. CONCLUSIONS: Lumiracoxib is rapidly and efficiently absorbed throughout the gastrointestinal tract.