[Metformin suppresses hypoxia-inducible factor-1α expression in cancer-associated fibroblasts to block tumor-stromal cross-talk in breast cancer].

OBJECTIVE: To investigate the mechanism of metformin for regulating tumor-stromal cell cross-talk in breast cancer. METHODS: Tumor associated fibroblasts (CAFs) co-cultured with breast cancer cells were treated with metformin, and the changes in expressions of hypoxia-inducible factor-1α (HIF-1α), p-AMPK, stroma-derived factor-1 (SDF-1) and interleukin-8 (IL-8) in the CAFs were detected using ELISA, RT-qPCR or Western blotting; Transwell assay was used to evaluate the invasiveness of the tumor cells and its changes following treatment with exogenous SDF-1, IL-8 and TGF-ß1. The effects of HIF-1α shRNA or overexpression plasmid, AMPK shRNA, and treatment with OG (a proline hydroxylase inhibitor) or 2-OXO (a proline hydroxylase activator) were examined on p-AMPK, HIF-1α, SDF-1 and IL-8 expressions and invasiveness of the CAFs. RESULTS: Metformin treatment significantly increased the expression levels of p-AMPK, SDF-1 and IL-8 (P<0.05) and decreased HIF-1α expression (P<0.05) without affecting AMPK expression level (P>0.05) in the CAFs. The invasion ability of metformintreated breast cancer cells was significantly decreased (P<0.05). Exogenous SDF-1 and IL-8, HIF-1α overexpression, and OGinduced upregulation of HIF-1α all significantly attenuated the inhibitory effects of metformin on breast cancer cell invasion (P<0.05) and HIF-1α, SDF-1 and IL-8 expressions in CAFs (P<0.05). Transfection with HIF-1α shRNA or treatment with 2-OXO significantly decreased the invasiveness of breast cancer cells (P<0.05). P-AMPK knockdown significantly suppressed the inhibitory effect of metformin on HIF-1α expression in CAFs and on invasion of breast cancer cells (P<0.05). Treatment with TGF-ß1 partially decreased the inhibitory effect of metformin on HIF-1α expression in CAFs and invasiveness of the breast cancer cells (P<0.05). CONCLUSION: Metformin suppresses HIF-1α expression in CAFs to block tumor-stromal cross talk in breast cancer.

Estrogen as a guardian of auditory health: Tsp1-CD47 axis regulation and noise-induced hearing loss.

OBJECTIVES: This study aimed to analyze the role of estrogen in noise-induced hearing loss (NIHL) and uncover underlying mechanisms. METHODS: An ovariectomized Sprague-Dawley rat model (OVX) was constructed to investigate the hearing threshold and auditory latency before and after noise exposure using the auditory brainstem response (ABR) test. The morphological changes were assessed using immunofluorescence, scanning electron microscopy and transmission electron microscopy. Proteomics and bioinformatics were used to analyze the mechanism. The findings were further verified through western blot and Luminex liquid suspension chip technology. RESULTS: After noise exposure, OVX rats exhibited substantially elevated hearing thresholds. A conspicuous delay in ABR wave I latency was observed, alongside increased loss of outer hair cells, severe collapse of stereocilia and pronounced deformation of the epidermal plate. Accordingly, OVX rats with estrogen supplementation exhibited tolerance to NIHL. Additionally, a remarkable upregulation of the thrombospondin 1 (Tsp1)-CD47 axis in OVX rats was discovered and verified. CONCLUSIONS: OVX rats were more susceptible to NIHL, and the protective effect of estrogen was achieved through regulation of the Tsp1-CD47 axis. This study presents a novel mechanism through which estrogen regulates NIHL and offers a potential intervention strategy for the clinical treatment of NIHL.

Improved Measurement of the Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay.

Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

Precision Measurement of Reactor Antineutrino Oscillation at Kilometer-Scale Baselines by Daya Bay.

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3} eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3} eV^{2} for the inverted mass ordering.

[Optic atrophy in a patient with axonal Charcot-Marie-Tooth disease 2A2A due to MFN2 gene mutations].

A 27-year-old male patient had progressive vision loss in both eyes, which was mainly manifested by impaired ganglion cells in the macular area, accompanied by systemic muscle atrophy in limbs. A complete mitochondrial exon gene detection was performed. The final diagnosis was bilateral optic atrophy and axonal Charcot-Marie-Tooth disease 2A2A caused by mutations of the MFN2 gene. There has been no effective treatment. Applications of nutrients to restore the mitochondrial function may alleviate the clinical symptoms.

[Influence of paper mixing pads thickness on the compressive strength of glass ionomer cement].

OBJECTIVE: To explore the influence of the thickness of mixed cardboard on the compressive strength of glass ionomer cement and the associated factors. METHODS: Three different types of glass ionomer cements were mixed on the top of 60, 40, 20 and 1 pieces of paper (P60, P40, P20 and P1), respectively. The compressive strength of the materials was tested after solidification, and the bubble rate was calculated with the assistance of scanning electron microscope. RESULTS: (1) Compressive strength: ① ChemFil Superior glass ionomer (CF): The average compressive strength of P1 group was the highest, which was significantly different from that of P40 and P60 groups (P values were 0.041 and 0.032 respectively); ② To Fuji IX GP glass ionomer (IX): The average compressive strength of P1 group was the highest, which was statistically different from that of P40 and P60 groups (P values were 0.042 and 0.038 respectively); ③ Glaslonomer FX-Ⅱ glass ionomer cement (FX): The average compressive strength of P1 group was the highest, which was statistically different from that of P20, P40 and P60 groups (P values were 0.031, 0.040 and 0.041 respectively), but there was no statistical difference among the other groups. All the three materials showed that the compressive strength of glass ions gradually increased with the decrease of the thickness of the blended paperboard, and the two materials had a highly linear negative correlation, the correlation coefficients of which were CF-0.927, IX-0.989, FX-0.892, respectively. (2) Scanning electron microscope: P1 group had the least bubbles among the three materials. CONCLUSION: It indicates that the thickness of mixed cardboard has a negative correlation with the compressive strength of glass ions. The thicker the mixed cardboard is, the greater the elasticity is. Excessive elasticity will accelerate the mixing speed when the grinding glass ions. Studies have shown that the faster the speed of artificial mixing is, the more bubbles is produced.The thicker ther mixed cardboard is, the more bubblesn are generated by glass ionomer cement, and the higher the compressive strength is. Using one piece of paper board to mix glass ionomer cement has the least bubbles and can obtain higher compressive strength.

First Measurement of High-Energy Reactor Antineutrinos at Daya Bay.

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{ß} isotopes in commercial reactors.

Mechanical properties of three-dimensionally printed titanium plates used in jaw reconstruction: preliminary study.

The aim of this study was to compare the mechanical properties of three-dimensionally (3D)-printed and conventional surgical plates used for the repair of maxillary or mandibular defects under the same experimental conditions, and to provide experimental evidence for the future application and clinical trial of 3D-printed individualized surgical plates. For the experimental group, two groups of surgical plates with thicknesses of 2.0 mm and 2.5 mm were designed and 3D-printed by electron beam melting, using Ti-6Al-4V as raw material. Conventional commercially available surgical plates with the same thickness were adopted as the control group. A Vickers hardness tester and universal testing machine were used to measure the mechanical properties of the plates (hardness, bending strength, tensile strength, and yield strength). The mechanical properties of 3D-printed surgical plates were significantly better than those of conventional surgical plates of the same thickness (P < 0.001). Comparing the surgical plates of different thickness, the 2.5 mm-thick plates had the highest bending strength in the experimental group (P < 0.001) and the best hardness (P < 0.001), bending strength (P = 0.001), tensile strength (P = 0.001), and yield strength (P = 0.001) in the control group. No statistical difference was found between the two kinds of plates in the experimental group in terms of hardness (P = 0.060), tensile strength (P = 0.096), and yield strength (P = 0.496). The 3D-printed surgical plates have better mechanical properties than the conventional ones.

Worldwide prevalence of suicidal ideation and suicide plan among people with schizophrenia: a meta-analysis and systematic review of epidemiological surveys.

Schizophrenia is a severe psychiatric disorder with high premature mortality rates. This is a meta-analysis and systematic review of the prevalence of suicidal ideation (SI) and suicide plan (SP) among people with schizophrenia. PubMed, Web of Science, Embase, and PsycINFO were systematically searched from their respective inception to October 10, 2020. Data on prevalence of SI and/or SP were synthesized using the random effects model. Twenty-six studies covering 5079 people with schizophrenia were included for meta-analysis. The lifetime and point prevalence of SI were 34.5% (95% CI: 28.2-40.9%), and 29.9% (95% CI: 24.2-35.6%), respectively. The lifetime prevalence of SP was 44.3% and the point prevalence of SP ranged between 6.4 and 13%. Subgroup and meta-regression analyses revealed that source of patients, survey countries, and sample size were significantly associated with the point prevalence of SI, while male proportion and quality assessment scores were significantly associated with the lifetime and point prevalence of SI. Survey time and mean age were significantly associated with lifetime prevalence of SI. Both SI and SP are common in people living with schizophrenia, especially in males and inpatients. Routine screening and effective interventions for SI and SP should be implemented in this population.

Impact of age and menopausal stage on serum anti-Müllerian hormone levels in middle-aged women.

OBJECTIVE: This study aimed to evaluate the association between age, menopausal stage and serum anti-Müllerian hormone (AMH) levels in middle-aged women. METHODS: In this cross-sectional study, the serum AMH levels of 288 healthy women aged 40-55 years (divided into age groups: 40-44, 45-49 and 50-55 years) were evaluated. Stages of Reproductive Aging Workshop + 10 criteria were used to categorize these women into menopausal stages: late reproductive, menopausal transition and early postmenopausal stages. The impact of age, menopausal stage and hormone replacement therapy on serum AMH levels was analyzed using multi-factor analysis of variance. Effects of body mass index, smoking status and oral contraceptive use were simultaneously considered. RESULTS: The median AMH level was 0.140 ng/ml. Log-AMH levels varied according to age group (variance = 20.113, F = 88.538, p < 0.001) and menopausal stage (variance = 5.543, F = 24.501, p < 0.001). An exponential model defined as AMH = 227,421.757 × e(-0.301 × age) was fit to describe the decline in AMH level with age. The 5th-95th percentiles of the AMH levels ranged from less than 0.020 to 3.150, less than 0.020 to 1.944 and less than 0.020 to 0.030 ng/ml in the aforementioned menopausal stages, respectively. CONCLUSION: Age and menopausal stage were associated with AMH levels; age had a greater impact on AMH than menopausal stage in middle-aged women.

[The 488th case: chronic diarrhea and abnormal liver function].

A 56-year-old female was admitted to Department of Gastroenterology at Peking Union Medical College Hospital with diarrhea for seven months, and abnormal liver function for six months. She had a history of type 1 diabetes. The main clinical manifestations were recurrent fatty diarrhea and abnormal liver function, accompanied by abdominal and retroperitoneal lymphadenopathy, elevated CA19-9 and CEA. Progressive impairment of hepatic synthetic function and shrinkage of liver developed in a short period of time. The pathology of liver biopsy suggested that nodular regeneration of hepatocytes was followed by hyperplasia of thin bile ducts after submassive necrosis. Intestinal mucosa biopsies were performed twice. The pathology showed that the intestinal villi were completely blunt, accompanied with crypt hyperplasia. Goblet cells disappeared with reduced mucin. Paneth cells were barely seen without intraepithelial infiltration of lymphocytes. Rifaximin was not effective, while glucocorticoids improved clinical situation. The diagnosis of autoimmune enteropathy was finally confirmed by multidisciplinary team including departments of gastroenterology, pathology, endocrinology, hematology, infectious diseases, and rheumatology. With the administration of glucocorticoid and sirolimus, diarrhea relieved and liver function returned to normal.

Correlation between CT and anatomopathological staging of kidney cancer.

Our Moroccan context is experiencing an increase in the frequency of renal tumors. This trend can be explained by the generalization of the use of imaging, in particular abdominal ultrasound, which has become almost systematic among general practitioners (Godley and Ataga, 2000 [1]). The specificity of kidney cancer is anatomopathological heterogenicity: histological type, nuclear grade, tumor stage, these elements constitute the most important prognostic factors. Renal biopsy appears to be a safe and reliable solution with a low risk of tumor seeding and complications, however it cannot provide all the detailed histological information needed. Hence the interest in the abdominal scanner. The abdominal scanner is the reference examination for the evaluation of renal tumors, it diagnoses the tumor, specifies these characteristics, it assesses the loco regional, venous extension. The objective of our study is to correlate pathological and CT findings of 70 kidney cancer in order to determine the reliability of CT in kidney cancer and its extension.

The correlation between the gleason score of the biopsy and that of the prostatectomy patch.

Since the advent of massive dosage of prostate specific antigen (PSA), prostate cancer has become a major public health problem. It is currently the most common cancer and the second leading cause of cancer death in men (after lung cancer). More than 670,000 new cases are diagnosed annually worldwide. This is a retrospective study including all patients treated for prostate cancer by radical prostatectomy at the Ibn Rochde University Hospital in Casablanca between January 2017 and December 2020, i.e. a period of 4 years. At the end of our study, we identified 18 cases of radical prostatectomy.

[A Meta-analysis on association between statins and colorectal cancer].

Objective: To explore the association between statins and colorectal cancer and provide evidence for the prevention of colorectal cancer. Methods: Literatures about statins and colorectal cancer published from January 2000 to January 2020 were retrieved from CNKI, Wanfang data, PubMed and Cochrane Library database. The literatures which met the inclusion criteria were collected, and the Newcastle-Ottawa Scale and Jadad score were used to assess the studies. Meta-analysis was performed with statistical software Revman 5.0 and Stata 12.1. Results: A total of 31 studies, involving more than 1.62 million subjects, were included in the analysis. The case-control study (RR=0.93, 95%CI: 0.88-0.98), the cohort study (RR=0.75, 95%CI: 0.63-0.88) and the randomized controlled trial (RR=0.79, 95%CI: 0.65-0.97) showed moderate protective effect of statins. Using statin <5 years (RR=0.86, 95%CI: 0.76-0.96), average daily dosage ≥34 mg (RR=0.81, 95%CI: 0.66-0.98) and lipid-soluble statins (RR=0.86, 95%CI: 0.74-0.99) also had preventive effect on colorectal cancer; while lovastatin (RR=1.07, 95%CI: 1.00-1.14) increased the risk of colorectal cancer. Conclusion: Statins have protective effect on colorectal cancer.

Retrocaval ureter: A case report and review of the literature.

Retrocaval ureter is a rare malformation. We report a case of right retrocaval ureter of type 1. The usual clinical manifestation being lumbar pain due to obstruction of the upper urinary tract, asymptomatic forms can also be encountered. Since the diagnosis was based on the CT-scan, the treatment was uncrossing with uretero-ureteral anastomosis by lumbotomy, with a satisfactory long-term result.

Post-traumatic adrenal hematoma: A case report and revue of literature.

Post-traumatic adrenal hematoma, which has rare but severe complications, is a difficult to diagnose condition. Only computed tomography, which is often performed systematically during lesional assessments of violent thoraco-abdominal trauma, can confirm the diagnosis. Symptoms are often masked by associated visceral or parietal lesions. Standard biological examinations are generally not very helpful. We will describe the case of a 47-year-old man who presented with a right adrenal hemorrhage following a road accident, for only associated lesion, a fracture of the middle arch of the first and 8th ribs, and the transverse process L1.

[Evaluation of the tolerance of the ureteral catheter JJ by the use of the USSQ self-questionnaire]. / Évaluation de la tolérance de la sonde JJ par l'utilisation de l'auto-questionnaire USSQ.

OBJECTIVE: Evaluation of the quality of life patients with a ureteral catheter JJ (US). METHOD: This study was conducted from 01/2016 to 15/02/2017, including all patients operated on a rise of US. The USSQ questionnaire (Ureteral Stent Symptom Questionnaire) validated in French in 2010 was filled during the perioperative period with SU in place (S1), 4 weeks after putting the US (S2) and 4 weeks after removal of the US (S3), it is grouped into 6 sections: urinary symptoms, body pain, general condition, professional impact, sexuality, other problems. The Wilcoxon test was used to compare the statistical averages. RESULTS: We identified 150 patients including 89 women (59.3%) and 61 men (40.7%). The average age of our patients is 49.5 years. The quality of life appeared to be significantly altered in all areas explored by the questionnaire: urinary symptoms had a mean score one week after the US rise (S1) was 29.5 versus 25.3 at four weeks after ablation (S3) of US at P<0.0001), pain persisted at four weeks after US ablation at an average S3 score of 10.6 versus 14.5 at S1 at P=0.003. The patients' EG was also altered after the placement of the SU: S1 of 16.6 versus S2 18.5 (P<0.0001), the presence of a US did not have a great impact on the activity professional active patients: active (S1 of 14.9 versus S3 of 13.3 P=0.6). But it was a sexual disability of the sexuality carrier: average score of 5.3 in S1 vs. 5.2 in S3 for a value=0.122. There is no significant difference if the US is raised urgently or in a scheduled manner. CONCLUSION: US appears to have a significant impact on the quality of life of patients. LEVEL OF EVIDENCE: 3.

[Decision regret analysis among Chinese patients receiving penile girth enhancement with acellular dermal matrix].

OBJECTIVE: To evaluate decision regret among patients receiving penile girth enhancement with acellular dermal matrix (PGE with ADM) and to investigate the potential indicators for decisional regret so as to facilitate the decision-making process for this special group. METHODS: In the study, 78 patients receiving PGE with ADM from Jun. 2016 to Jan. 2019 at Peking University People's Hospital and cooperative hospitals were eligible. Penile girth was taken by only one surgeon 1 week before surgery. Hospital anxiety and depression scale (HAD), international index of erectile function (IIEF) and a 10 cm long visual analogue scale named visualized penile image (VPI) were applied to measure psychological burden, erectile function and satisfaction with penile image respectively at the same time. All the patients were followed up for 3 months. Decision regret scale (DRS) was adopted for measuring decisional regret. Multivariate analysis of variance was applied to investigate the potential indicators for regret. Data analysis process was conducted with SPSS (version 24.0; SPSS, Chicago, IL, USA). RESULTS: Mean penile girth recorded before intervention was (8.29±0.30) cm and increased to (9.46±0.29) cm post surgery (t=76.28, P < 0.01). As for both subscales of HAD measuring psychological burden, a signi-ficant reduction in the mean score was seen, that is, 2.8±1.3 (t=19.28, P < 0.05) for anxiety and 3.0±1.2 (t=20.67, P < 0.05) for depression, respectively. The average score of VPI increased by 3.7±1.1 (t=30.63, P < 0.05). There was no significant change in the average score of IIEF measuring erectile satisfaction (t=1.60, P=0.11). Twenty-nine (38.2%) patients expressed regret to some degree, and the mean DRS score was 23.4±14.8. The scores of DRS correlated negatively with scores of visualized penis image (r=-0.348, P < 0.01), and positively with scores of anxiety (r=0.760, P < 0.01) and depression subscale (r=0.471, P < 0.01). The scores of DRS was irrelevant to those of IIEF (r=0.02, P=0.867). The patients with high annual income (> 120 000 yuan) and education level above undergraduate were more prone to experience decision regret after intervention (P < 0.01). CONCLUSION: PGE with ADM did augment penile girth and lower psychological burden, the regret rate of which was acceptably low among the patients. High income and good education might indicate more post-operative regret. Additional decision-making aids should be offered to patients with high income and education level above high school.

Virus shedding dynamics in asymptomatic and mildly symptomatic patients infected with SARS-CoV-2.

OBJECTIVES: Asymptomatic patients, together with those with mild symptoms of coronavirus disease 2019 (COVID-19), may play an important role in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission. However, the dynamics of virus shedding during the various phases of the clinical course of COVID-19 remains unclear at this stage. METHODS: A total of 18 patients found to be positive for SARS-CoV-2 infection by real-time reverse transcription PCR (RT-PCR) assay and admitted to Chongqing University Central Hospital between 29 January and 5 February 2020 were enrolled into this study. Medical data, pulmonary computed tomographic (CT) scan images and RT-PCR results were periodically collected during the patients' hospital stay. All participants were actively followed up for 2 weeks after discharge. RESULTS: A total of nine (50%) asymptomatic patients and nine (50%) patients with mild symptoms of COVID-19 were identified at admission. Six patients (66.7%) who were asymptomatic at admission developed subjective symptoms during hospitalization and were recategorized as being presymptomatic. The median duration of virus shedding was 11.5, 28 and 31 days for presymptomatic, asymptomatic and mildly symptomatic patients, separately. Seven patients (38.9%) continued to shed virus after hospital discharge. During the convalescent phase, detectable antibodies to SARS-CoV-2 and RNA were simultaneously observed in five patients (27.8%). CONCLUSIONS: Long-term virus shedding was documented in patients with mild symptoms and in asymptomatic patients. Specific antibody production to SARS-CoV-2 may not guarantee virus clearance after discharge. These observations should be considered when making decisions regarding clinical and public health, and when considering strategies for the prevention and control of SARS-CoV-2 infection.

Diagnostic accuracy of computed tomography colonography in patients at high risk for colorectal cancer: a meta-analysis.

AIM: The aim was to explore the diagnostic value of computed tomographic colonography (CTC) compared with conventional colonoscopy in individuals at high risk for colorectal cancer. METHOD: PubMed, Embase, the Cochrane Library and the Web of Science were searched by two independent reviewers for potentially eligible studies published up to 31 October 2018 that were based on a per-patient analysis. stata, meta-disc and revman were used to perform this meta-analysis. A random-effect model was used, and a subgroup analysis was conducted to explore the sources of heterogeneity. RESULTS: A total of 14 full-text articles, involving 3578 patients, were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and the area under the summary receiver operating characteristic curve of CTC for detecting polyps ≥ 6 mm were 0.87 (95% CI 0.83-0.90), 0.90 (95% CI 0.86-0.93), 9.08 (95% CI 6.28-13.13), 0.14 (95% CI 0.11-0.18) and 0.94 (95% CI 0.92-0.96), respectively. For polyps ≥ 10 mm, the pooled sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of CTC were 0.91 (95% CI 0.86-0.94), 0.98 (95% CI 0.95-0.99), 40.36 (95% CI 19.16-85.03), 0.90 (95% CI 0.06-0.14) and 0.98 (95% CI 0.96-0.99), respectively. CONCLUSION: In this meta-analysis, CTC had high diagnostic accuracy for detecting polyps ≥ 6 mm and ≥ 10 mm in patients at high risk of developing colorectal cancer and it had a higher sensitivity and specificity for detecting polyps ≥ 10 mm than polyps ≥ 6 mm. However, the results should be used cautiously due to the significant heterogeneity.