Effect of Real-Time Computer-Aided Polyp Detection System (ENDO-AID) on Adenoma Detection in Endoscopists-in-Training: A Randomized Trial.

BACKGROUND: The effect of computer-aided polyp detection (CADe) on adenoma detection rate (ADR) among endoscopists-in-training remains unknown. METHODS: We performed a single-blind, parallel-group, randomized controlled trial in Hong Kong between April 2021 and July 2022 (NCT04838951). Eligible subjects undergoing screening/surveillance/diagnostic colonoscopies were randomized 1:1 to receive colonoscopies with CADe (ENDO-AID[OIP-1]) or not (control) during withdrawal. Procedures were performed by endoscopists-in-training with <500 procedures and <3 years' experience. Randomization was stratified by patient age, sex, and endoscopist experience (beginner vs intermediate level, <200 vs 200-500 procedures). Image enhancement and distal attachment devices were disallowed. Subjects with incomplete colonoscopies or inadequate bowel preparation were excluded. Treatment allocation was blinded to outcome assessors. The primary outcome was ADR. Secondary outcomes were ADR for different adenoma sizes and locations, mean number of adenomas, and non-neoplastic resection rate. RESULTS: A total of 386 and 380 subjects were randomized to CADe and control groups, respectively. The overall ADR was significantly higher in the CADe group than in the control group (57.5% vs 44.5%; adjusted relative risk, 1.41; 95% CI, 1.17-1.72; P < .001). The ADRs for <5 mm (40.4% vs 25.0%) and 5- to 10-mm adenomas (36.8% vs 29.2%) were higher in the CADe group. The ADRs were higher in the CADe group in both the right colon (42.0% vs 30.8%) and left colon (34.5% vs 27.6%), but there was no significant difference in advanced ADR. The ADRs were higher in the CADe group among beginner (60.0% vs 41.9%) and intermediate-level (56.5% vs 45.5%) endoscopists. Mean number of adenomas (1.48 vs 0.86) and non-neoplastic resection rate (52.1% vs 35.0%) were higher in the CADe group. CONCLUSIONS: Among endoscopists-in-training, the use of CADe during colonoscopies was associated with increased overall ADR. (ClinicalTrials.gov, Number: NCT04838951).

Third Asia-Pacific consensus recommendations on colorectal cancer screening and postpolypectomy surveillance.

The Asia-Pacific region has the largest number of cases of colorectal cancer (CRC) and one of the highest levels of mortality due to this condition in the world. Since the publishing of two consensus recommendations in 2008 and 2015, significant advancements have been made in our knowledge of epidemiology, pathology and the natural history of the adenoma-carcinoma progression. Based on the most updated epidemiological and clinical studies in this region, considering literature from international studies, and adopting the modified Delphi process, the Asia-Pacific Working Group on Colorectal Cancer Screening has updated and revised their recommendations on (1) screening methods and preferred strategies; (2) age for starting and terminating screening for CRC; (3) screening for individuals with a family history of CRC or advanced adenoma; (4) surveillance for those with adenomas; (5) screening and surveillance for sessile serrated lesions and (6) quality assurance of screening programmes. Thirteen countries/regions in the Asia-Pacific region were represented in this exercise. International advisors from North America and Europe were invited to participate.

Orientation-aware plasma cell-free DNA fragmentation analysis in open chromatin regions informs tissue of origin.

Cell-free DNA (cfDNA) in human plasma is a class of biomarkers with many current and potential future diagnostic applications. Recent studies have shown that cfDNA molecules are not randomly fragmented and possess information related to their tissues of origin. Pathologies causing death of cells from particular tissues result in perturbations in the relative distribution of DNA from the affected tissues. Such tissue-of-origin analysis is particularly useful in the development of liquid biopsies for cancer. It is therefore of value to accurately determine the relative contributions of the tissues to the plasma DNA pool in a simultaneous manner. In this work, we report that in open chromatin regions, cfDNA molecules show characteristic fragmentation patterns reflected by sequencing coverage imbalance and differentially phased fragment end signals. The latter refers to differences in the read densities of sequences corresponding to the orientation of the upstream and downstream ends of cfDNA molecules in relation to the reference genome. Such cfDNA fragmentation patterns preferentially occur in tissue-specific open chromatin regions where the corresponding tissues contributed DNA into the plasma. Quantitative analyses of such signals allow measurement of the relative contributions of various tissues toward the plasma DNA pool. These findings were validated by plasma DNA sequencing data obtained from pregnant women, organ transplantation recipients, and cancer patients. Orientation-aware plasma DNA fragmentation analysis therefore has potential diagnostic applications in noninvasive prenatal testing, organ transplantation monitoring, and cancer liquid biopsy.

Joint effect between bisphenol A and alcohol consumption on benign prostatic hyperplasia: A case-control study in Hong Kong Chinese males.

BACKGROUND: Whether bisphenol A (BPA) exposure is a contributing factor to benign prostatic hyperplasia (BPH) remains unclear. This study evaluated the association between chronic BPA exposure and BPH risk, and explored whether this association was modified by alcohol drinking. METHODS: This study included a total of 650 BPH cases and 650 controls recruited from the same hospital in Hong Kong during 2011-2016. Chronic BPA exposure level was estimated by a validated cumulative BPA exposure index (CBPAI). We performed unconditional logistic regression model to examine the association of BPH risk with potential sources of BPA exposure via oral intake and CBPAI. We further tested the interactions between CBPAI and alcohol consumption habits on BPH risk. RESULTS: A positive exposure-response relationship was observed between CBPAI and BPH risk. Frequent BPA exposure via oral intake of foods heated in a plastic box/bag (odds ratio [OR] = 3.52, 95% confidence interval [CI]: 1.51-8.22), cooling water in a plastic bottle (OR = 2.65, 95% CI: 1.33-5.27), or using a plastic cup to contain hot water (OR = 4.14, 95% CI: 1.02-16.89), was significantly associated with increased BPH risk. Compared with nonalcohol drinkers, alcohol drinkers was insignificantly associated with BPH risk (OR = 1.10, 95% CI: 0.77-1.57), but it demonstrated a more remarkable positive gradient between CBPAI exposure and BPH risk among alcohol drinkers, indicating an additive interaction between CBPAI and alcohol on BPH risk (synergy index = 4.24, 95% CI: 1.21-14.94). CONCLUSIONS: Chronic oral BPA exposure increased BPH risk with a positive exposure-response relationship among Hong Kong Chinese, and alcohol drinking amplified the effect of BPA on BPH. Hence, minimizations of containing food or water/beverage in plastic containers and drinking alcohol are recommended in the community to mitigate BPH risk. Future larger and designated studies are warranted.

Comparison between robotic natural orifice specimen extraction surgery and traditional laparoscopic low anterior resection for middle and low rectal cancer: A propensity score matching analysis.

BACKGROUND AND OBJECTIVES: This study aimed to find the advantages of robotic natural orifice specimen extraction surgery (NOSES) for middle and low rectal cancer, compared with traditional laparoscopic low anterior resection (LAR). METHODS: Patients receiving robotic NOSES or traditional laparoscopic LAR were retrospectively enrolled from 2013-10 to 2019-06, with middle and low rectal cancer, maximum diameter ≤ 5 cm, pT1-3 or ypT1-3 stage, no distant metastases. The baseline of the two groups was balanced using the propensity score matching method. Surgical quality, postoperative recovery, and long-term oncological outcomes were compared. RESULTS: Totally 137 eligible patients with robotic NOSES and 137 matched patients with traditional laparoscopic LAR were enrolled. Robotic NOSES had a significantly lower open conversion rate (0 vs. 4.4%, p = .030), less intraoperative hemorrhage (50 ml vs. 80 ml, p < .001) and longer distance from distal resection margin of low rectal cancer (1.5 cm vs. 1.0 cm, p = .030). Robotic NOSES significantly reduced the 30-day postoperative complication rate of Clavien-Dindo grade II or higher (17.5% vs. 31.4%, p = .008), promoted gastrointestinal and urinary function recovery, reduced postoperative pain and hospital stay (6.0 vs. 7.0 d, p = .022). The two groups were similar in long-term survival. CONCLUSIONS: Compared with traditional laparoscopic LAR, robotic NOSES had significant advantages in improving surgical quality and promoting postoperative recovery.

The role of metacognition and its indirect effect through cognitive attentional syndrome on fear of cancer recurrence trajectories: A longitudinal study.

OBJECTIVE: This longitudinal study mapped distinct trajectories of fear of cancer recurrence (FCR) over 12 months among patients with breast (BC) or colorectal (CRC) cancer, and examined if metacognition, indirectly via attentional bias, intrusive thoughts and avoidance (hallmarks of cognitive attentional syndrome; CAS) predicted FCR trajectory membership. METHODS: Two hundred and seventy BC (n = 163) or CRC (n = 107) patients were assessed at 8-weeks, 3-, 6-, and 12-months postsurgery on a measure of FCR (FCRI-SF). Metacognition (MCQ-30), Intrusive and Avoidant Thoughts (CIES-R) and attentional bias (dot-probe tasks) were assessed at baseline. Latent growth mixture modeling identified FCR trajectories. Fully-adjusted Multinomial Logistic Regression identified whether direct and indirect effects of metacognition through CAS determined FCR trajectory membership. RESULTS: Three distinct FCR trajectories were identified, namely, low-stable (62.4%), high-stable (29.2%), and recovery (8.3%). Negative beliefs about worry, cognitive confidence, and age predicted FCR trajectories (χ2 (6) = 38.31, P<.001). Compared with Low-stable group, Recovery FCR patients held greater Negative beliefs about worry (OR = 1.13, P = .035) and High-stable FCR patients reported poorer Cognitive confidence (OR = 1.12, P = .004). The effect of Negative beliefs about worry was partially mediated by avoidance (ß = .06, 95% CIs 0.03-0.12) and fully mediated by intrusive thoughts (ß = .14, 95% CIs 0.08-0.20). Attentional bias did not predict FCR trajectories. CONCLUSIONS: While most patients experienced low level of FCR, 3 in 10 persistently worried about cancer returning over the first 12-months postsurgery. Modifying metacognitive knowledge to interrupt maladaptive cognitive processing including intrusion and avoidance may be an effective therapeutic intervention for patients at risk of persistent FCR.

Eukaryotic elongation factor-2 kinase expression is an independent prognostic factor in colorectal cancer.

BACKGROUND: Prognostication of patients with colorectal cancer (CRC) currently relies on tumor-node-metastasis (TNM) staging but clinical outcomes of patients of the same histoclinical stage are heterogeneous. It is therefore imperative to devise novel molecular tests to stratify CRC patients. Our previous work demonstrated that eukaryotic elongation factor-2 kinase (EEF2K) is a tumor suppressor in CRC. Herein, we investigated EEF2K expression in CRC and determined its relationship with clinicopathological parameters. METHODS: Quantitative RT-PCR and Westerns blots were used to examine EEF2K expression in primary tumor and the adjacent non-tumor tissues of CRC patients (n = 20). Kaplan-Meier curves and Cox regression analysis were used to assess the association between clinical outcomes of CRC patients and EEF2K protein expression determined by immunohistochemistry on tissue microarray (n = 151). RESULTS: EEF2K was significantly downregulated at both mRNA and protein levels in tumors of CRC patients. Univariate Cox regression analysis revealed that CRC patients with high tumor grade, advanced TNM staging and low EEF2K expression were associated with worse overall survival. Multivariate analysis further demonstrated that low EEF2K expression was an independent factor for predicting poorer overall survival in CRC patients (p = 0.014; Hazard ratio = 2.951; 95% confidence interval: 1.240-7.024). The 5-year survival rate was 82.8% in the EEF2K-high-expression group versus 63.9% in the EEF2K-low-expression group (p = 0.0118). The association of overall survival with EEF2K expression in CRC patients was verified in The Cancer Genome Atlas (TCGA) cohort. CONCLUSIONS: EEF2K is downregulated in CRC and its expression can be employed as a prognostic marker for CRC patients independent of TNM staging.

Transcervical minimally invasive esophagectomy using da Vinci® SP™ Surgical System: a feasibility study in cadaveric model.

BACKGROUND: This is a preclinical cadaveric study to investigate the feasibility of transcervical esophagectomy using a novel single-port robotic surgical system. METHODS: A 40-mm cervical incision was created over left supraclavicular fossa. The novel da Vinci® SP™ Surgical System was introduced through a wound retraction port. The mobilization of esophagus was performed using da Vinci SP from cervical, thoracic to abdominal segments. Lymph nodes were dissected en bloc with esophagus. RESULTS: The transcervical esophagectomy with complete mobilization of the cervical, thoracic, and abdominal esophagus was completed in 60 min. The procedure was completed using the novel da Vinci SP Surgical System, which was introduced via the cranial side over the left cervical incision. No additional port was used for retraction and dissection, and the esophageal hiatus could be reached after complete transcervical dissection. CONCLUSION: This preclinical study demonstrated that transcervical esophagectomy is technically feasible and can be completed with the novel da Vinci SP Surgical System without additional ports or assistance. This will serve as an important step to the performance of robotic transcervical esophagectomy without the necessity of one-lung ventilation.

Liver- and Colon-Specific DNA Methylation Markers in Plasma for Investigation of Colorectal Cancers with or without Liver Metastases.

BACKGROUND: Measurement of DNA derived from different tissues in the circulating DNA pool can provide important information regarding the presence of many pathological conditions. However, existing methods involving genome-wide bisulfite sequencing are relatively expensive and may present challenges for large-scale analysis. METHODS: Through identifying differentially methylated regions in the liver and colon compared with other tissues, we identified 2 markers and developed corresponding droplet digital PCR assays. Plasma concentrations of liver-derived and colon-derived DNA were measured for 13 liver transplant recipients, 40 liver cancer patients, and 62 colorectal cancer (CRC) patients (27 with and 35 without liver metastases). RESULTS: In liver transplant recipients, the fractional concentration of liver-derived DNA measured using the liver-specific methylation marker and donor-specific alleles showed good correlation (Pearson R = 0.99). In liver cancer patients, the concentration of liver-derived DNA correlated positively with the maximal dimension of the tumor (Spearman R = 0.74). In CRC patients with and without liver metastasis, the plasma concentrations of colon-derived DNA (median, 138 copies/mL and 4 copies/mL, respectively) were increased compared with the 30 healthy controls (26 had undetectable concentrations). The absolute concentration of liver-derived DNA provided a better differentiation between CRC patients with and without liver metastasis compared with the fractional concentration (area under ROC curve, 0.85 vs 0.75). CONCLUSIONS: Quantitative analysis of plasma DNA with tissue-specific methylation patterns using droplet digital PCR is applicable for the investigation of cancers and assessing organ transplantation. This approach is useful for differentiating patients with and without metastases to other organs.

Plasma DNA tissue mapping by genome-wide methylation sequencing for noninvasive prenatal, cancer, and transplantation assessments.

Plasma consists of DNA released from multiple tissues within the body. Using genome-wide bisulfite sequencing of plasma DNA and deconvolution of the sequencing data with reference to methylation profiles of different tissues, we developed a general approach for studying the major tissue contributors to the circulating DNA pool. We tested this method in pregnant women, patients with hepatocellular carcinoma, and subjects following bone marrow and liver transplantation. In most subjects, white blood cells were the predominant contributors to the circulating DNA pool. The placental contributions in the plasma of pregnant women correlated with the proportional contributions as revealed by fetal-specific genetic markers. The graft-derived contributions to the plasma in the transplant recipients correlated with those determined using donor-specific genetic markers. Patients with hepatocellular carcinoma showed elevated plasma DNA contributions from the liver, which correlated with measurements made using tumor-associated copy number aberrations. In hepatocellular carcinoma patients and in pregnant women exhibiting copy number aberrations in plasma, comparison of methylation deconvolution results using genomic regions with different copy number status pinpointed the tissue type responsible for the aberrations. In a pregnant woman diagnosed as having follicular lymphoma during pregnancy, methylation deconvolution indicated a grossly elevated contribution from B cells into the plasma DNA pool and localized B cells as the origin of the copy number aberrations observed in plasma. This method may serve as a powerful tool for assessing a wide range of physiological and pathological conditions based on the identification of perturbed proportional contributions of different tissues into plasma.

Quantitation of faecal Fusobacterium improves faecal immunochemical test in detecting advanced colorectal neoplasia.

OBJECTIVE: There is a need for an improved biomarker for colorectal cancer (CRC) and advanced adenoma. We evaluated faecal microbial markers for clinical use in detecting CRC and advanced adenoma. DESIGN: We measured relative abundance of Fusobacterium nucleatum (Fn), Peptostreptococcus anaerobius (Pa) and Parvimonas micra (Pm) by quantitative PCR in 309 subjects, including 104 patients with CRC, 103 patients with advanced adenoma and 102 controls. We evaluated the diagnostic performance of these biomarkers with respect to faecal immunochemical test (FIT), and validated the results in an independent cohort of 181 subjects. RESULTS: The abundance was higher for all three individual markers in patients with CRC than controls (p<0.001), and for marker Fn in patients with advanced adenoma than controls (p=0.022). The marker Fn, when combined with FIT, showed superior sensitivity (92.3% vs 73.1%, p<0.001) and area under the receiver-operating characteristic curve (AUC) (0.95 vs 0.86, p<0.001) than stand-alone FIT in detecting CRC in the same patient cohort. This combined test also increased the sensitivity (38.6% vs 15.5%, p<0.001) and AUC (0.65 vs 0.57, p=0.007) for detecting advanced adenoma. The performance gain for both CRC and advanced adenoma was confirmed in the validation cohort (p=0.0014 and p=0.031, respectively). CONCLUSIONS: This study identified marker Fn as a valuable marker to improve diagnostic performance of FIT, providing a complementary role to detect lesions missed by FIT alone. This simple approach may improve the clinical utility of the current FIT, and takes one step further towards a non-invasive, potentially more accurate and affordable diagnosis of advanced colorectal neoplasia.

SLC25A22 Promotes Proliferation and Survival of Colorectal Cancer Cells With KRAS Mutations and Xenograft Tumor Progression in Mice via Intracellular Synthesis of Aspartate.

BACKGROUND & AIMS: Many colorectal cancer (CRC) cells contain mutations in KRAS. Analyses of CRC cells with mutations in APC or CTNNB1 and KRAS identified SLC25A22, which encodes mitochondrial glutamate transporter, as a synthetic lethal gene. We investigated the functions of SLC25A22 in CRC cells with mutations in KRAS. METHODS: We measured levels of SLC25A22 messenger RNA and protein in paired tumor and nontumor colon tissues collected from 130 patients in Hong Kong and 17 patients in China and compared protein levels with patient survival times. Expression of SLC25A22 was knocked down in KRAS mutant CRC cell lines (DLD1, HCT116, LOVO, SW480, SW620, and SW1116) and CRC cell lines without mutations in KRAS (CACO-2, COLO205, HT29, and SW48); cells were analyzed for colony formation, proliferation, glutaminolysis and aspartate synthesis, and apoptosis in Matrigel and polymerase chain reaction array analyses. DLD1 and HCT116 cells with SLC25A22 knockdown were grown as xenograft tumors in nude mice; tumor growth and metastasis were measured. SLC25A22 was expressed ectopically in HCT116 cells, which were analyzed in vitro and grown as xenograft tumors in nude mice. RESULTS: Levels of SLC25A22 messenger RNA and protein were increased in colorectal tumor tissues compared with matched nontumor colon tissues; increased protein levels were associated with shorter survival times of patients (P = .01). Knockdown of SLC25A22 in KRAS mutant CRC cells reduced their proliferation, migration, and invasion in vitro, and tumor formation and metastasis in mice, compared with cells without SLC25A22 knockdown. Knockdown of SLC25A22 reduced aspartate biosynthesis, leading to apoptosis, decreased cell proliferation in KRAS mutant CRC cells. Incubation of KRAS mutant CRC cells with knockdown of SLC25A22 with aspartate increased proliferation and reduced apoptosis, which required GOT1, indicating that oxaloacetate is required for cell survival. Decreased levels of oxaloacetate in cells with knockdown of SLC25A22 reduced regeneration of oxidized nicotinamide adenine dinucleotide and reduced nicotinamide adenine dinucleotide phosphate. Reduced oxidized nicotinamide adenine dinucleotide inhibited glycolysis and decreased levels of adenosine triphosphate, which inactivated mitogen-activated protein kinase kinase and extracellular signal-regulated kinase signaling via activation of AMP-activated protein kinase. An increased ratio of oxidized nicotinamide adenine dinucleotide phosphate to reduced nicotinamide adenine dinucleotide phosphate induced oxidative stress and glutathione oxidation, which suppressed cell proliferation. Asparagine synthetase mediated synthesis of asparagine from aspartate to promote cell migration. CONCLUSIONS: SLC25A22 promotes proliferation and migration of CRC cells with mutations KRAS, and formation and metastasis of CRC xenograft tumors in mice. Patients with colorectal tumors that express increased levels of SLC25A22 have shorter survival times than patients whose tumors have lower levels. SLC25A22 induces intracellular synthesis of aspartate, activation of mitogen-activated protein kinase kinase and extracellular signal-regulated kinase signaling and reduces oxidative stress.

Risk of Advanced Adenomas in Siblings of Individuals With Advanced Adenomas: A Cross-Sectional Study.

BACKGROUND & AIMS: The risk of colorectal neoplasms among siblings of patients with advanced adenomas is not clear. We determined the prevalence of advanced adenomas in the siblings of patients with advanced adenomas and compared it with that of siblings of individuals without these lesions. METHODS: In a blinded, cross-sectional study, colonoscopies were performed (from 2010 through 2014), at 2 hospitals in Hong Kong on 200 asymptomatic siblings of patients with advanced adenomas (exposed; mean age, 58.2 ± 6.3 years; adenomas ≥10 mm, high-grade dysplasia, villous, or tubulovillous) and 400 age- and sex-matched siblings of subjects with normal findings from colonoscopies and no family history of colorectal cancer (unexposed; mean age, 58.1 ± 6 years). We recruited 1 sibling per family. The primary outcome was prevalence of advanced adenomas. RESULTS: Baseline demographics (ie, aspirin use, smoking, body mass index, and metabolic diseases) did not differ significantly between exposed and unexposed individuals. The prevalence of advanced adenoma was 11.5% among the exposed subjects and 2.5% among the unexposed subjects (matched odds ratio [mOR] = 6.05; 95% confidence interval [CI]: 2.74-13.36; P < .001). The prevalence of adenomas ≥10 mm was higher among exposed than unexposed siblings (10.5% vs 1.8%; mOR = 8.59; 95% CI: 3.44-21.45; P < .001), as was the prevalence of villous adenomas (5.5% vs 1.3% in unexposed; mOR = 6.28; 95% CI: 2.02-19.53; P = .001) and all colorectal adenomas (39.0% vs 19.0% in unexposed; mOR = 3.29; 95% CI: 2.16-5.03; P < .001). Two cancers were detected in exposed siblings and none in unexposed siblings. CONCLUSIONS: In a cross-sectional study of subjects undergoing colonoscopy in Hong Kong, siblings of individuals with at least 1 advanced adenoma had a 6-fold increased odds of advanced adenoma compared with subjects who had a sibling with a screening colonoscopy with no identified neoplasia. ClinicalTrials.gov, Number: NCT01593098.

A novel miR-203-DNMT3b-ABCG2 regulatory pathway predisposing colorectal cancer development.

Colorectal cancer (CRC) is a major cause of mortality and morbidity worldwide. The majority of studies to date focused on genetic mutations and epigenetic changes that drive the CRC carcinogenesis process. Xenobiotic transporters play an important role in safeguarding our body from external toxic substances. These transporters lining the gastrointestinal tract protect us from dietary carcinogens. This study aimed to investigate the downregulation of an efflux transporter ABCG2 in CRC versus normal colon mucosa, so as to shed light on its relevance to CRC initiation and progression. We found that ABCG2 expression is at least 50-fold lower in adenomatous polyps and colon carcinoma specimens obtained from CRC patients than in their matched pair of adjacent normal colon mucosa. The underlying mechanism(s) for ABCG2 under-expression in CRC is currently not known. To this end, aberrant promoter methylation of ABCG2 has been reported to cause its repression in a few cancer types including renal carcinoma and multiple myeloma. In this study, miR-203 was found to be downregulated in all polyps and CRC specimens, relative to adjacent normal colon mucosa. We demonstrated that the de novo DNA methyltransferase DNMT3b is a direct target of miR-203. Importantly, by relieving the repression on DNMT3b, the lower expression of miR-203 in CRC caused ABCG2 promoter methylation and remarkable lower ABCG2 expression in colon cancer cell lines and the patient CRC specimens. The restoration of ABCG2 function via modulating this new microRNA-methylation mechanism in precancerous cells may represent an attractive strategy to delay the carcinogenesis process. © 2016 Wiley Periodicals, Inc.

Early results of a safety and feasibility clinical trial of a novel single-port flexible robot for transoral robotic surgery.

The aim of this study was to describe the early results of a phase 1 safety and feasibility clinical trial of the first clinical use of a novel robot for transoral robotic surgery (TORS)-the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA). Study design of this study is prospective clinical trial. The methods used in this study are prospective innovation, development, exploration, assessment, and long-term study phase 1 clinical trial. Early results of six patients underwent TORS with the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA) demonstrate access the nasopharynx, oropharynx, larynx, and hypopharynx. There were no conversions of the robotic surgical system. There were no serious adverse events or adverse events related to the use of the robot at 30-day follow-up for all six patients. The early results of this safety and feasibility trial of the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA) clearly demonstrate that the device is safe and that it is feasible in performing TORS to access the nasopharynx, oropharynx, larynx, and hypopharynx.

Screening strategies for colorectal cancer among patients with nonalcoholic fatty liver disease and family history.

Patients with nonalcoholic fatty liver disease (NAFLD) and family history of colorectal cancer (CRC) are at higher risks but how they should be screened remains uncertain. Hence, we evaluated the cost-effectiveness of CRC screening among patients with NAFLD and family history by different strategies. A hypothetical population of 100,000 subjects aged 40-75 years receive: (i) yearly fecal immunochemical test (FIT) at 50 years; (ii) flexible sigmoidoscopy (FS) every 5 years at 50 years; (iii) colonoscopy 10 yearly at 50 years; (iv) colonoscopy 10 yearly at 50 years among those with family history/NAFLD and yearly FIT at 50 years among those without; (v) colonoscopy 10 yearly at 40 years among those with family history/NAFLD and yearly FIT at 50 years among those without and (vi) colonoscopy 10 yearly at 40 years among those with family history/NAFLD and colonoscopy 10 yearly at 50 years among those without. The incremental cost-effectiveness ratio (ICER) was studied by Markov modeling. It was found that colonoscopy, FS and FIT reduced incidence of CRC by 49.5, 26.3 and 23.6%, respectively. Using strategies 4, 5 and 6, the corresponding reduction in CRC incidence was 29.9, 30.9 and 69.3% for family history, and 33.2, 34.7 and 69.8% for NAFLD. Compared with no screening, strategies 4 (US$1,018/life-year saved) and 5 (US$7,485) for family history offered the lowest ICER, whilst strategy 4 (US$5,877) for NAFLD was the most cost-effective. These findings were robust when assessed with a wide range of deterministic sensitivity analyses around the base case. These indicated that screening patients with family history or NAFLD by colonoscopy at 50 years was economically favorable.

Association of distal hyperplastic polyps and proximal neoplastic lesions: a prospective study of 5613 subjects.

BACKGROUND AND AIMS: Current evidence of whether distal hyperplastic polyps (HPs) are markers of proximal neoplasia (PN) is mixed. We evaluated the association between distal neoplasia and synchronous PN in asymptomatic subjects. METHODS: We recruited 5819 Chinese asymptomatic screening participants 50 to 70 years of age who underwent colonoscopy in Hong Kong from 2008 to 2014, of whom 206 subjects with distal advanced neoplasia or cancer were excluded. The association between distal pathology (tubular adenomas [TAs], HPs, no polyps) and proximal pathology (PN, proximal advanced neoplasia [PAN]) was assessed by multivariate regression models, overall and stratified by the Asia Pacific Colorectal Screening scoring system (scores of 4-7, high risk; scores of 0-3, lower risk). RESULTS: The prevalence of PN in the no distal polyps group, distal HPs group, and distal TAs group was 14.8%, 19.3%, and 29.4%, respectively. The corresponding prevalence of PAN was 1.8%, 3.2%, and 3.5%. Participants with distal HPs did not have significantly higher odds of PN (adjusted odds ratio [AOR] 1.24; 95% confidence interval [CI], 0.97-1.59; P = .089), and their association with PAN was marginally significant (AOR 1.77; 95% CI, 1.00-3.13; P = .052), except in lower risk subjects for whom the odds of PAN were marginally higher in the distal HPs group than the no distal polyps group (AOR 1.97; 95% CI, 1.01-3.85; P = .048). Overall, the distal polyps group had significantly lower odds of PN than the distal TAs group (AOR 0.55; 95% CI, 0.40-0.76; P < .001). The increased risk of PN and PAN among those with distal HPs was modest. CONCLUSIONS: A direct association between distal HPs and PN is lacking, and this implies a need for a multivariate assessment of the risk of PAN. Recommending colonoscopy for every patient with distal HPs detected by screening sigmoidoscopy is not supported by this study.

Translation and validation of the traditional Chinese version of the faecal incontinence quality of life scale.

PURPOSE: Psychometric evaluation with tools such as the faecal incontinence quality of life scale is an essential component of clinical assessment. Currently, there is no translated Traditional Chinese version of the scale. A validated translated version may help to improve the quality of healthcare received in countries with Chinese minorities (0.5, 1.2 and 4.0% of the UK, USA and Australian population, respectively) as well as local population of Hong Kong. The purpose of this study is to validate the Traditional Chinese version of the faecal incontinence quality of life scale (FIQL). METHODS: The FIQL questionnaire was translated into Traditional Chinese Language followed by linguistic validation. It was then tested on 55 patients with faecal incontinence and 93 controls in the colorectal outpatients clinic. Faecal incontinence severity index was also used for the assessment of disease severity. RESULTS: Internal consistency was good/excellent for all scales (Cronbach's alpha >0.70, between 0.71 and 0.93). The intra-class correlation indicated a high stability over time with coefficients ranging between 0.78 and 0.90. Test and retest of all four scales found no significant differences of mean scores between baseline and retest. The mean faecal incontinence quality of life scale scores of all four domains improved significantly after treatment of 10 patients whose faecal incontinence severity index scores decreased by 50 % of their pre-treatment scores, hence indicating good sensitivity. CONCLUSIONS: This study demonstrates the linguistic and psychometric validity of the traditional Chinese version of the faecal incontinence quality of life scale.

Exploiting a novel miR-519c-HuR-ABCG2 regulatory pathway to overcome chemoresistance in colorectal cancer.

Colorectal cancer (CRC) is a major cause of mortality and morbidity worldwide. While surgery remains the mainstay of treatment for early stage CRC, adjuvant chemotherapy is usually given to reduce the risk of recurrence after colectomy. Overexpression of a multidrug resistance (MDR) transporter ABCG2 in vitro has been shown to cause resistance to 5-fluorouracil (5-FU) and irinotecan, components of the most commonly adopted regimens for treating CRC. Both anticancer drugs are known ABCG2 substrates. An effective way to predict drug response may provide guidance for better cancer treatment. We investigated the effect of ABCG2 dysregulation on cancer cell sensitivity to chemotherapy using pairs of snap-frozen paraffin-embedded archival blocks of human colorectal cancer tissues and their matched non-cancerous colon tissues from CRC patients. In CRC patients responding to chemotherapy, the tumors were found to have remarkable lower ABCG2 expression than the adjacent normal colon tissues. On the contrary, the tumors from patients not responding to 5-FU-based chemotherapy have higher ABCG2 level than the adjacent normal tissues. The high ABCG2 expression in the tumor is associated with the concomitant overexpression of the mRNA binding protein HuR but a low expression of miR-519c because miR-519c is known to target both ABCG2 and HuR. Further investigation in CRC cell lines revealed that the ABCG2 overexpression was caused by an interplay between miR-519c, HuR and the length of the 3' untranslated region (UTR) of ABCG2. These parameters may be further developed as useful biomarkers to predict patient response to adjuvant chemotherapy. Besides being predictive biomarkers, the microRNAs and mRNA binding protein identified may also be potential drug targets for modulating ABCG2 to combat resistance in CRC chemotherapy.

Noninvasive detection of cancer-associated genome-wide hypomethylation and copy number aberrations by plasma DNA bisulfite sequencing.

We explored the detection of genome-wide hypomethylation in plasma using shotgun massively parallel bisulfite sequencing as a marker for cancer. Tumor-associated copy number aberrations (CNAs) could also be observed from the bisulfite DNA sequencing data. Hypomethylation and CNAs were detected in the plasma DNA of patients with hepatocellular carcinoma, breast cancer, lung cancer, nasopharyngeal cancer, smooth muscle sarcoma, and neuroendocrine tumor. For the detection of nonmetastatic cancer cases, plasma hypomethylation gave a sensitivity and specificity of 74% and 94%, respectively, when a mean of 93 million reads per case were obtained. Reducing the sequencing depth to 10 million reads per case was found to have no adverse effect on the sensitivity and specificity for cancer detection, giving respective figures of 68% and 94%. This characteristic thus indicates that analysis of plasma hypomethylation by this sequencing-based method may be a relatively cost-effective approach for cancer detection. We also demonstrated that plasma hypomethylation had utility for monitoring hepatocellular carcinoma patients following tumor resection and for detecting residual disease. Plasma hypomethylation can be combined with plasma CNA analysis for further enhancement of the detection sensitivity or specificity using different diagnostic algorithms. Using the detection of at least one type of aberration to define an abnormality, a sensitivity of 87% could be achieved with a specificity of 88%. These developments have thus expanded the applications of plasma DNA analysis for cancer detection and monitoring.