Study of diagnostic value of congenital hypertrophy of retinal pigment epithelium in Chinese familial adenomatous polyposis patients.

BACKGROUND: Congenital hypertrophy of retinal pigment epithelium (CHRPE) is an important characteristic of familial adenomatous polyposis (FAP) patients. However, more evidence about its sensitivity, specificity, and diagnostic value for FAP is needed to determine whether CHRPE is a reliable marker. METHODS: Clinical features of FAP patients were investigated using in-person evaluations. Family members of FAP patients were evaluated with an indirect ophthalmoscope to determine whether they had CHRPE. We defined three diagnostic criteria for CHRPE (criteria A, B and C) based on their shape, quantity and size. Those with negative colonoscopy results and gene mutation results were classified as healthy controls. RESULTS: Of a total of 23 FAP families, 21 families were CHRPE-positive (91.3%). Among those 21 families, 47 individuals had CHRPE, including 33 FAP patients, 9 APC gene mutation carriers, and 5 individuals younger than 18 years who were later confirmed to have FAP. Fifty individuals had no CHRPE (5 FAP patients and 45 individuals without APC gene mutations and colorectal adenoma). The average number of CHRPE lesions per person was 5.81, and CHRPE was located mostly in the posterior pole in the eye fundus; 76.7% of individuals had CHRPE in both eyes. The sensitivity of the three CHRPE criteria ranged from 78.8 to 90.4%, with the highest sensitivity found for criterion A (90.4%), which had a specificity of 100% for healthy controls and sporadic colorectal cancer patients. CONCLUSION: CHRPE has vital diagnostic and screening value because of its high sensitivity for discovering FAP and APC gene mutation carriers.

Six years of colorectal cancer mortality surveillance in the screening population for a risk stratified screening program.

OBJECTIVE: To evaluate the impact of a colorectal cancer (CRC) risk predicting system on CRC mortality rates. METHOD: An organized population screening program targeted at all the subjects (n = 102,076) at age 40-74 in nine towns of Jiashan county, China was conducted from 2007 to 2012. All of the screening participants were first triaged into high-risk & low-risk groups by a questionnaire and two fecal immunuochemical tests, only the high-risk subjects were subject to colonocopy. The screening participants were surveyed death caused by CRC for a total of six years after the enrollment. The CRC mortality in subgroups of the screening population was analyzed. RESULTS: A total of 82,184 (80.51 % of the targeted population) screening participants were identified. CRC death were recorded for 142 subjects (28.819 per 105 person-years). The age-adjusted relative risk(RR) of CRC death in the high-risk subjects (n = 12862, 84.48 per 105 person-years) was 3.92 (95 % CI = 2.81-5.49) compared with the low-risk subjects (n = 69322, 18.52 per 105 person-years). In the high-risk group, the age-adjusted RR of CRC death for those accepted colonoscopies (51.44 per 105 person-years) compared with those refused colonoscopies (187.94 per 105 person-years, P < 0.0001) was 0.34 (95 % CI = 0.21-0.56). The first three years after screening has seen the largest difference of CRC death hazard in both comparing groups. CONCLUSION: The high-risk subjects triaged by the risk predicting system have a higher CRC mortality rate than the low-risk subjects, especially in the first three years after screening. Refusal of colonoscopy is risky behavior for the high-risk subject.

Plausibility of an extensive use of stool DNA test for screening advanced colorectal neoplasia.

PURPOSE: FIT-DNA test is supposed to be highly sensitive for advanced colorectal neoplasms and is advocated in some developed countries, but lack extensive use in developing countries. METHODS: A case control study on stool DNA test for colorectal neoplasms patients was conducted from March 2016 to October 2017 in China. We recruited CRC, colorectal neoplasms and normal controls from ambulatory patients and screening attendees in communities. The stool DNA was tested by a molecular panel similar as ColoGuard in addition to fecal immunochemical test(FIT) in a blinded manner. A risk scoring system was used to determine the positiveness of tests with histological diagnosis as its reference standard. RESULTS: Eligible subjects included 203 colorectal cancer (CRC), 49 advanced adenoma (AA), 156 non-advanced adenoma(NAA) and 431 normal controls(NC). The FIT-DNA kit detected 97.5% CRC (n = 198, 95% CI = 95.4-99.7) and 53.1% AA (n = 26, 95% CI = 39.1-67.0), with specificity of 89.1% (95% CI = 86.2-92.0) in NC and 88.1% (95% CI = 85.5-90.7) in non-advanced controls. The FIT embedded in the kit alone identified 94.6% (n = 192, 95% CI = 91.5-97.7) CRC and 36.7% AA (n = 18, 95% CI = 23.2-50.2). Consistency of KRAS mutation, BMP3 methylation, NDRG4 methylation in 26 paires stool DNA and CRC tumor DNA were 80.9%, 71.4% and 81.8%, respectively. CONCLUSION: At the sacrifice of significantly decreased specificity, a FIT-DNA kit may has better sensitivity than FIT for predicting advanced colorectal adenoma, but not for predicting colorectal cancer. More evidences are needed for the extensive use of FIT-DNA testing.

Effects of subitems in the colorectal cancer screening protocol on the Chinese colorectal cancer screening program: an analysis based on natural community screening results.

BACKGROUND: To date, no single colorectal cancer (CRC) screening strategy has been determined to be applicable worldwide. In China, a CRC screening protocol that combines double fecal immunochemical tests (FITs) and a high-risk factor questionnaire (HRFQ) as the first stage of screening and colonoscopy as the second stage of screening (scenario A) was adapted by the Chinese Ministry of Health in 2006. However, applying this CRC screening protocol nationally remains difficult because its effectiveness and convenience are controversial. This study evaluated the effects of subitems of the CRC screening protocol in China. METHODS: CRC screening results (scenario A) from Jiashan County, China, (2007-2009) were used to analyze the detection rates of CRC and advanced neoplasms as well as the cost-effectiveness of the protocol. Scenario A was divided into scenarios B-G (by selecting some items at the first stage of screening) for analysis. RESULTS: Compared with scenario A, removing the whole HRFQ (scenario F) reduced advanced neoplasm and adenoma detections by 29.8 and 41.2%, respectively, whereas the whole HRFQ accounted for 10.1% of the total screening cost. Removing FITs (scenario G) reduced CRC, advanced neoplasm and adenoma detections by 71.8, 56.9 and 47.7%, respectively, and the costs per case of CRC and advanced neoplasm were 82.0 and 19.1% higher, respectively, than those in scenario A. In scenarios B-E (deleting some high-risk factor questions on the HRFQ), the odds ratios (ORs) of the detection rates and costs per CRC, advanced neoplasm, adenoma, and neoplasm case were near 1.00. Scenarios C and D reduced the high-risk population and total screening costs by less than 6.0 and 4.1%, respectively. Scenarios E and B (FITs and a personal history of cancer or colorectal adenoma were reserved) reduced the high-risk population by 17.6 and 24.2% and the total screening costs by 11.2 and 15.4%, respectively, while the numbers of CRC cases were not missed, and advanced neoplasms detected decreased by only 5 and 11%, respectively. CONCLUSION: The results of this study demonstrate that FITs and a personal history of colorectal adenoma are the most effective items in the Chinese CRC screening protocol.

Cost-Effectiveness between Double and Single Fecal Immunochemical Test(s) in a Mass Colorectal Cancer Screening.

This study investigated the cost-effectiveness between double and single Fecal Immunochemical Test(s) (FIT) in a mass CRC screening. A two-stage sequential screening was conducted. FIT was used as a primary screening test and recommended twice by an interval of one week at the first screening stage. We defined the first-time FIT as FIT1 and the second-time FIT as FIT2. If either FIT1 or FIT2 was positive (+), then a colonoscopy was recommended at the second stage. Costs were recorded and analyzed. A total of 24,419 participants completed either FIT1 or FIT2. The detection rate of advanced neoplasm was 19.2% among both FIT1+ and FIT2+, especially high among men with age ≥55 (27.4%). About 15.4% CRC, 18.9% advanced neoplasm, and 29.9% adenoma missed by FIT1 were detected by FIT2 alone. Average cost was $2,935 for double FITs and $2,121 for FIT1 to detect each CRC and $901 for double FITs and $680 for FIT1 to detect each advanced neoplasm. Double FITs are overall more cost-effective, having significantly higher positive and detection rates with an acceptable higher cost, than single FIT. Double FITs should be encouraged for the first screening in a mass CRC screening, especially in economically and medically underserved populations/areas/countries.

Optimizing sampling device for the fecal immunochemical test increases colonoscopy yields in colorectal cancer screening.

The fecal immunochemical test (FIT) that quantifies hemoglobin concentration is reported to be better than qualitative FIT and the reason for its superiority has not been interpreted. To evaluate and understand the superiority of quantitative FIT, a representative randomly selected population (n=2355) in Jiashan County, China, aged 40-74 years was invited for colorectal cancer screening in 2012. Three fecal samples were collected from each participant by one optimized and two common sampling devices, and then tested by both quantitative and qualitative FITs. Colonoscopy was provided independently to all participants. The performances of five featured screening strategies were compared. A total of 1020 participants were eligible. For screening advanced neoplasia, the positive predictive value (PPV) and the specificity of the strategy that tested one sample dissolved in an optimized device by quantitative FIT [PPV=40.8%, 95% confidence interval (CI): 27.1-54.6; specificity=96.8%, 95% CI: 95.7-98.0] were significantly improved over the strategy that tested one sample dissolved in the common device by qualitative FIT (PPV=14.1%, 95% CI: 8.2-19.9; specificity=87.9%, 95% CI: 85.8-89.9), whereas the sensitivity did not differ (39.2 and 37.3%, P=0.89). Similar disparity in performance was observed between the strategies using qualitative FIT to test one sample dissolved in optimized (PPV=29.5%, 95% CI: 18.1-41.0; specificity=95.3%, 95% CI: 94.0-96.7) versus common sampling devices. High sensitivity for advanced neoplasia was observed in the strategy that tested two samples by qualitative FIT (52.9%, 95% CI: 39.2-66.6). Quantitative FIT is better than qualitative FIT for screening advanced colorectal neoplasia. However, the fecal sampling device might contribute most significantly toward the superiority of quantitative FIT.

Cost-effectiveness of colorectal cancer screening protocols in urban Chinese populations.

Colorectal cancer (CRC) takes a second and fourth position in the incidence and mortality lists respectively among all malignant tumors in urban populations in China. This study was designed to evaluate the cost-effectiveness of two different CRC screening protocols: faecal occult blood test (FOBT) alone, and FOBT plus a high-risk factor questionnaire (HRFQ) as the respective initial screens, followed by colonoscopy. We developed a Markov model to simulate the progression of a cohort of 100,000 average risk asymptomatic individuals moving through a defined series of states between the ages of 40 to 74 years. The parameters used for the modeling came from the CESP (Comparison and Evaluation of Screening Programs for Colorectal Cancer in Urban Communities in China) study and published literature. Eight CRC screening scenarios were tested in the Markov model. The cost-effectiveness of CRC screening under each scenario was measured by an incremental cost-effectiveness ratio (ICER) compared with a scenario without CRC screening. The study revealed that a combined use of FOBT and HRFQ is preferable in CRC screening programs as an initial screening instrument. Annual FOBT+HRFQ screening is recommended for those who have a negative initial result and those who have a positive result but have failed to continue to colonoscopic examination. Repeated colonoscopy (for those with a positive result in initial screening but a negative colonoscopy result) should be performed at a ten-year interval instead of one-year. Such a protocol would cost 7732 Yuan per life year saved, which is the most cost-effective option. In conclusion, the current Chinese Trial Version for CRC Screening Strategy should be revised in line with the most cost-effective protocol identified in this study.

Predictive power of quantitative and qualitative fecal immunochemical tests for hemoglobin in population screening for colorectal neoplasm.

The aim of this study was to evaluate the performance of qualitative and quantitative fecal immunochemical tests (FITs) in population screening for colorectal neoplasm. A total of 9000 participants aged between 40 and 74 years were enrolled in this study. Each participant received two stool sampling tubes and was asked to simultaneously submit two stool samples from the same bowel movement. The stool samples of each participant were tested using an immunogold labeling FIT dipstick (qualitative FIT) and an automated fecal blood analyzer (quantitative FIT). Colonoscopy was performed for those who test positive in either FIT. The positive predictive values and population detection rates of the FITs for predicting colorectal neoplasm were compared. A total of 6494 (72.16%) participants simultaneously submitted two stool samples. The diagnostic consistency for a positive result between quantitative and qualitative FITs was poor (κ=0.278, 95% confidence interval=0.223-0.333). The positive predictive values of the quantitative FIT were significantly higher than those of the qualitative FIT for predicting large (≥1 cm) adenomas (23 cases, 14.29% and 16 cases, 6.72%, P=0.013) and colorectal cancer (10 cases, 6.21% and 5 cases, 2.10%, P=0.034); however, the population detection rate for advanced neoplasm of the quantitative FIT was not significantly different from that of the qualitative FIT. Quantitative FIT is superior to qualitative FIT in predicting advanced colorectal neoplasm during colorectal cancer screening. Further studies are needed to elucidate the causes of the predictive superiority.

[Comparison between application of fecal occult blood quantitive testing instrument and colloidal gold strip method in colorectal cancer screening].

OBJECTIVE: To compare the performances of fecal occult blood quantitive testing instrument and colloidal gold strip method in colorectal cancer screening. METHODS: A representative random population of 9000 subjects aging between 40 and 74 years old were selected from Xuxiang, Haining city, Zhejiang province, by random cluster sampling method in year 2011. The fecal samples from each subject were separately detected by the two methods, namely fecal occult blood quantitive testing instrument and colloidal gold strip method. The positive result was standardized by hemoglobin concentration (HGB) ≥ 100 ng/ml under the application of quantitive testing instrument, or color-developing by colloidal gold strip method. The positive subjects from either method would be provided a further colonoscopy examination for pathological diagnosis. The positive rate and consistency of the two methods were compared, as well as the positive predictive value and population detecting rate of the colorectal cancer and adenoma. RESULTS: A total of 6475 (71.9%) subjects submitted their two fecal samples according to our requirement in 9000 subjects. There were separately 319 positive cases (4.9%) and 146 positive cases (2.3%) by the performances of fecal occult blood quantitive testing instrument and colloidal gold strip method, including 45 positive in both tests (Kappa = 0.168, 95%CI:0.119-0.217).184 out of the 319 positive cases (57.7%) in the test by quantitive testing instrument and 89 out of 146 positive cases (61.0%) in the test by colloidal gold strip method received the colonoscopy examination. There were no significant statistical differences between the two methods in the positive predictive value of colorectal cancer (P > 0.05) , developing adenoma and non-developing adenoma.However, the population detecting rate of the colorectal cancer and developing adenoma were higher in the test by quantitive testing instrument (26 cases, 0.402%) than it in the test by colloidal gold strip method (10 cases, 0.154%). The difference showed statistical significance (χ(2) = 7.131, P < 0.01). CONCLUSION: The performances of fecal occult blood quantitive testing instrument might be better than colloidal gold strip method in colorectal cancer screening. However, the results need to be further verified.

Diagnostic inconsistency of faecal immunochemical tests for haemoglobin in population screening of colorectal cancer.

BACKGROUND: There is currently very little data available on the consistency of quantitative and qualitative faecal immunochemical test (FIT) for colorectal cancer screening. METHODS: A representative random population (n=1889, 40-74 year olds) in Jiashan, China was invited for FIT screening in 2012. Faecal samples were collected by a single specimen collection device and simultaneously tested by a quantitative FIT (OC-SENSOR, OC) and two qualitative FITs (FIT A and FIT B with intrinsic positive haemoglobin cut-off concentrations of 20 µg Hb/g faeces and 40 µg Hb/g faeces, respectively). The observational criteria for a positive result of the qualitative FIT were set according to the density of the colour appearing in the test strip. The results produced by the quantitative and qualitative FIT for each sample were compared. κ coefficient was used to measure consistency. RESULTS: A total of 1368 (72.4%) individuals returned faecal samples. Both FIT A and FIT B precisely identified all faecal samples with haemoglobin concentration above 100 µg Hb/g faeces, but the overall consistency was poor for OC & FIT A (κ=0.32, 95% CI 0.20-0.44) and was moderate for OC & FIT B (κ=0.74, 95% CI 0.64-0.85). A more favourable consistency (κ=0.64, 95% CI 0.57-0.72) was achieved when a different positive criterion was employed for FIT A. CONCLUSIONS: The diagnostic inconsistency between quantitative and qualitative FITs mainly exists in the faecal samples with low haemoglobin concentrations. Refining the criterion for a positive result may be a feasible way to improve the accuracy of qualitative FIT.

[Clinical value of radial endorectal ultrasound in the assessment of preoperative staging of rectal carcinoma].

OBJECTIVE: To evaluate the clinical value of radial endorectal ultrasound (ERUS) in the assessment of preoperative staging of rectal carcinoma. METHODS: One hundred and ten patients with rectal cancer underwent preoperative endorectal ultrasound (ERUS) examination in our hospital from February 2010 to September 2011. ERUS was performed using a Hitachi 900, Hitachi HI Vision Preirus US scanner, with a 5 - 10 MHz rigid rotating radial transducer and a focal length of 2 - 5 cm. The size, shape, echo pattern, infiltration depth, degree of circumferential involvement, extra-rectal invasion of the lesions and lymph node involvement were observed. The results of ERUS staging were compared with histopathological findings of the surgical specimens. RESULTS: The accuracy of ERUS for T staging was 91.4%. The accuracy of ERUS in diagnosing stage T1, T2, T3, T4 cancers was 92.7%, 88.2%, 88.2% and 96.4%, respectively. The sensitivity of ERUS in diagnosing stage T1, T2, T3, T4 cancers was 92.3%, 72.7%, 85.4% and 71.4%, respectively. The specificity of ERUS in diagnosing stage T1, T2, T3, T4 cancer was 92.9%, 92.0%, 90.3% and 100.0%, respectively. Comparing the consistency of preoperative T-staging and postoperative pathological results, the Kappa value was 0.75, with a considerable consistency. The sensitivity, specificity, and accuracy of ERUS in the assessment of lymph node metastasis were 74.2%, 89.9% and 85.5%, respectively. Comparing the consistency of preoperative N-staging and postoperative pathological results, the Kappa value was 0.64, with a considerable consistency. CONCLUSIONS: ERUS is a practical and accurate tool in assessment of preoperative staging of rectal tumors in regard to tumor invasion depth (T) and regional lymph node status (N), with advantages of simple operation, less pain, and high accuracy.

Serum M2-pyruvate kinase: A promising non-invasive biomarker for colorectal cancer mass screening.

AIM: To explore the value of serum M2-pyruvate kinase (M2-PK) in colorectal cancer (CRC) mass screening. METHODS: We conducted a molecular epidemiology study in Hangzhou, China, from year 2006 to year 2008. Serum samples were collected from 93 CRC, 41 advanced adenomas, 137 adenomas, 47 non-adenomatous polyps, and 158 normal participants in a community setting. Serum M2-PK and carcinoembryonic antigen (CEA) were measured using Enzyme-linked immunosorbent assay. SPSS 16.0 software was used to perform data analysis. Area under the receiver operating characteristic curve (AUC), sensitivity, and specificities were estimated for serum M2-PK in diagnosis of colorectal lesions and compared with CEA. RESULTS: Average serum M2-PK value among 158 normal people was 2.96 U/mL and not affected by gender (P = 0.47) or age (P = 0.59). Average serum M2-PK (U/mL) was 14.75 among stage III and 13.10 among stage I and II CRC patients, about 4 times higher than that among normal people. Average serum M2-PK was 8.58, 6.70, 5.13 and 2.51 U/mL among advanced adenoma, adenomas, non-adenomatous polyps, and inflammatory bowel disease patients, respectively. AUC for serum M2-PK was greater than that for CEA among all colorectal lesions. AUC for serum M2-PK was 0.89 (0.84, 0.94) (95% confidence interval), higher than that for CEA [0.70 (0.62-0.79)] in CRC stage I and II, 0.89 (0.84-0.94) vs 0.73 (0.63-0.83) in CRC stage III, 0.81 (0.74-0.86) vs 0.63 (0.53 - 0.73) in advanced adenomas, 0.69 (0.64-0.76) vs 0.54 (0.47-0.60) in adenomas, and 0.69 (0.62-0.78) vs 0.58 (0.48-0.68) in non-adenomatous polyps. The diagnostic sensitivity for all colorectal lesions increased with decrease in the cut-off value of serum M2-PK. The diagnostic sensitivity (%) of serum M2-PK was 100.00 for CRC, 95.12 advanced adenoma, 82.48 adenoma, and 82.98 non-adenomatous polyp. There were no CRC cases missed and 40.51% of unnecessary colonoscopies were avoided when the cut-off value was 2.00 U/mL. CONCLUSION: Serum M2-PK can be used as a primary screening test in CRC mass screening. It may be a promising non-invasive biomarker for CRC early detection.

[Primary evaluation of a mass screening program for colorectal tumor in China].

OBJECTIVE: To evaluate a colorectal cancer screening program by tumor detection rate and discussing its application values. METHOD: In total, 43 713 subjects were recruited in the screening program who were the registered people aged 40 - 74 in Xiacheng and Jiashan during year 2007 - 2009. The first screening involved questionnaire survey of colorectal cancer related risk factors and fecal occult blood test (FOBT), colonoscopy was performed when a positive result was observed in the first screening. If polyps were found during colonoscopy, biopsy and pathological diagnosis were carried out. The screening data were analyzed and the tumor detection rate was calculated according to age or sex. RESULTS: 6489 subjects (14.85%) belonged to the high risk group of colorectal cancer in the first screening, in which 4701 subjects finished complete colonoscopy. Finally, 569 colorectal neoplasm were diagnosed, the detection rate was 12.10% (95%CI: 11.17% - 13.04%). It included 52 colorectal cancer (1.11%, 95%CI: 0.81% - 1.41%), 183 advanced adenoma (3.89%, 95%CI: 3.34% - 4.45%), 334 non-advanced adenoma (7.10%, 95%CI: 6.37% - 7.84%). The highest detective rate was observed in male group that aged 70 - 74 (22.81%, 95%CI: 16.98% - 28.70%), the lowest detective rate was observed in female group aged 40 - 44 (2.49%, 95%CI: 0.79% - 4.20%). CONCLUSION: The current colorectal cancer screening program in China works well, but the revision of the program is necessary.

Performance of a colorectal cancer screening protocol in an economically and medically underserved population.

The performance of combining fecal immunochemical tests (FITs) and a high-risk factor questionnaire (HRFQ) in colorectal cancer (CRC) screening in economically and medically underserved populations is uncertain. This study investigated the performance of a CRC screening protocol of combining FITs and an HRFQ as primary screening methods in a rural Chinese population. A CRC mass screening was conducted using FITs and an HRFQ as the first and colonoscopy as the second stage of screening in Jiashan, 2007-2009. The target population was 31,963 residents in three communities. The compliance was 84.7% for HRFQ, 76.4% for FITs, and 78.7% for colonoscopy. The detected rates of cancer, adenoma, nonadenomatous polyps, and advanced neoplasm were 2.7%, 14.8%, 5.9%, and 8.9% by FITs, which were higher than those by HRFQ (0.5%, 9.2%, 4.8%, and 3.8%, respectively). There was no significant difference in detected rate for nonadenomatous polyps between FITs and HRFQ. A total of 41.2% adenomas, 53.2% nonadenomatous polyps, and 29.8% advanced neoplasms were detected by HRFQ but missed by FITs. Positive predictive value of the screening protocol of combining FITs and HRFQ for advanced neoplasm was 5.7%, which was higher than FITs alone. Men had a higher prevalence of advanced neoplasm than women. Results indicate that combining FITs and HRFQ as primary screening methods is an efficient CRC screening strategy in economically and medically underserved populations.

Performance value of high risk factors in colorectal cancer screening in China.

AIM: To analyze the performance value of high risk factors in population-based colorectal cancer (CRC) screening in China. METHODS: We compared the performance value of the immunochemical fecal occult blood test (iFOBT) and other high risk factors questionnaire in a population sample of 13 214 community residents who completed both the iFOBT and questionnaire investigation. Patients with either a positive iFOBT and/or questionnaire were regarded as a high risk population and those eligible were asked to undergo colonoscopy. RESULTS: The iFOBT had the highest positive predictive value and negative predictive value in screening for advanced neoplasia. The iFOBT had the highest sensitivity, lowest number of extra false positive results associated with the detection of one extra abnormality for screening advanced neoplasias and adenomas. A history of chronic cholecystitis or cholecystectomy, chronic appendicitis or appendectomy, and chronic diarrhea also had a higher sensitivity than a history of adenomatous polyps in screening for advanced neoplasias and adenomas. The sensitivity of a history of chronic cholecystitis or cholecystectomy was highest among the 10 high risk factors in screening for non-adenomatous polyps. A history of chronic appendicitis or appendectomy, chronic constipation, chronic diarrhea, mucous and bloody stool, CRC in first degree relatives, malignant tumor and a positive iFOBT also had higher sensitivities than a history of adenomas polyps in screening for non-adenomatous polyps. Except for a history of malignant tumor in screening for non-adenomatous polyps, the gain in sensitivity was associated with an increase in extra false positive results associated with the detection of one extra abnormality. CONCLUSION: The iFOBT may be the best marker for screening for advanced neoplasias and adenomas. Some unique high risk factors may play an important role in CRC screening in China.

Barrier-focused intervention to increase colonoscopy attendance among nonadherent high-risk populations.

AIM: To increase attendance for colonoscopy among nonadherent high-risk individuals for colorectal cancer (CRC) screening in China. METHODS: During the first 12 mo without intervention, only 428 of the 2398 high-risk subjects attended a scheduled colonoscopy examination. The 1970 subjects who did not attend for CRC screening were enrolled in the present study. Prior barrier investigation was performed to ascertain the reasons for nonadherence. A barrier-focused intervention program was then established and implemented among eligible nonadherent subjects by telephone interviews and on-site consultations. The completion rates of colonoscopy during the first 12 mo without intervention and the second 12 mo with intervention were compared. Variations in the effect of the intervention on some high-risk factors and barrier characteristics were analyzed using logistic regression. RESULTS: 540 subjects who were not eligible were excluded from the study. The colonoscopy attendance rate was 23.04% (428/1858) during the first 12 mo without intervention, and 37.69% (539/1430) during the second 12 mo with intervention (P < 0.001). Logistic regression analysis showed that the intervention was more effective among subjects with only objective barriers (OR: 34.590, 95% CI: 23.204-51.563) or subjects with some specific high-risk characteristics: first-degree relatives diagnosed with CRC (OR: 1.778, 95% CI: 1.010-3.131), personal history of intestinal polyps (OR: 3.815, 95% CI: 1.994-7.300) and positive result for immunochemical fecal occult blood testing (OR: 2.718, 95% CI: 1.479-4.996). CONCLUSION: The barrier-focused telephone or on-site consultation intervention appears to be a feasible means to improve colonoscopy attendance among nonadherent high-risk subjects for CRC screening in China.

[Application of serum protein markers to distinguish familial adenomatous polyposis (FAP) and sporadic colorectal adenomas].

OBJECTIVE: To screen out specifically-expressed serum protein markers in familial adenomatous polyposis (FAP) and to establish a serum protein fingerprint diagnostic model for distinguishing FAP from sporadic colorectal adenomas. METHODS: Serum samples were collected from 19 FAP cases and 16 sporadic colorectal adenomas with informed consent. Serum protein fingerprint profiles were detected by SELDI-TOF-MS with CM 10 protein chip to screen out FAP adenoma-related serum protein markers, and support vector machine (SVG) technique was used to establish the diagnostic model to distinguish FAP from sporadic colorectal adenomas. RESULTS: Six differently-expressed protein peaks (P < 0.01) were detected. Among them proteins of 5640, 3160, 4180 and 4290 m/z were highly expressed in FAP adenomas, and proteins of 3940 and 3400 m/z were highly expressed in sporadic colorectal adenomas. The accuracy of diagnostic model established with SVG to distinguish FAP adenomas and sporadic colorectal adenomas was 94.7% and 93.7%, respectively. CONCLUSION: SELDI-TOF-MS can be effectively used to screen out the differentially expressed serum protein markers in FAP adenomas and sporadic colorectal adenomas, and a diagnostic model build by SVG to distinguish them has been successfully established. Therefore, a useful breakthrough point for research on molecular mechanisms of FAP pathogenesis is provided.

Barriers to colorectal cancer screening: a case-control study.

AIM: To investigate barriers to colorectal cancer (CRC) screening in a community population. METHODS: We conducted a community-based case-control study in an urban Chinese population by questionnaire. Cases were selected from those completing both a fecal occult blood test (FOBT) case and colonoscopy in a CRC screening program in 2004. Control groups were matched by gender, age group and community. Control 1 included those having a positive FOBT but refusing a colonoscopy. Control 2 included those who refused both an FOBT and colonoscopy. RESULTS: The impact of occupation on willingness to attend a colorectal screening program differed by gender. P for heterogeneity was 0.009 for case vs control group 1, 0.01 for case versus control group 2, and 0.80 for control group 1 vs 2. Poor awareness of CRC and its screening program, characteristics of screening tests, and lack of time affected the screening rate. Financial support, fear of pain and bowel preparation were barriers to a colonoscopy as a screening test. Eighty-two percent of control group 1 and 87.1% of control group 2 were willing attend if the colonoscopy was free, but only 56.3% and 53.1%, respectively, if it was self-paid. Multivariate odds ratios for case vs control group 1 were 0.10 among those unwilling to attend a free colonoscopy and 0.50 among those unwilling to attend a self-paid colonoscopy. CONCLUSION: Raising the public awareness of CRC and its screening, integrating CRC screening into the health care system, and using a painless colonoscopy would increase its screening rate.

[Effect of microRNA143 expression on cell proliferation in colonic carcinoma].

OBJECTIVE: To investigate the effect of microRNA143 on cell proliferation and K-ras expression in colorectal carcinoma. METHODS: Northern blot was used to examine the expression of miR-143 in colorectal carcinoma and adjacent normal tissues. A miR-143 expression vector was constructed and transfected into a human colon adenocarcinoma cell line SW480. Cell proliferation was evaluated by MTT assay. RT-PCR and Western blot were used to examine the expression of K-ras oncogene in transfected cells. RESULTS: The level of mature miR-143 was lower in tumors compared with adjacent normal tissues in 81% of colorectal carcinoma specimens. In transfected cells, the increased accumulation of miR-143 inhibited the cell proliferation, and resulted in approximately 40.3% decrease of K-ras protein levels, but had no effect on level of K-ras mRNA. CONCLUSION: The increased accumulation of miR-143 inhibits the proliferation of transfected cells, and results in down-regulation of K-ras protein in colorectal carcinoma.

[Detection of adenomatous polyposis coli gene mutations in 31 familial adenomatous polyposis families by using denaturing high performance liquid chromatography].

OBJECTIVE: To analyze the adenomatous polyposis coli (APC) gene mutations in familial adenomatous polyposis (FAP) in Chinese. METHODS: DNA was extracted from blood samples taken from 31 FAP families, and all exons of the APC gene were amplified with touch-down PCR. APC gene mutations were screened by denaturing high performance liquid chromatography followed by sequencing if abnormal profile was detected. RESULTS: Twelve categories of APC gene mutations were found in 15 FAP families (48.39%) including 4 novel mutations in coding region and 3 mutations in introns. The 4 novel mutations in coding region were frameshift mutations and located in codons 255, 677, 1192 and 1403 respectively. Most mutations were clustered in exon 15 of APC gene leading to frameshift and accounted for 86.67%. Others were nonsense mutations (13.33%). CONCLUSION: The mutation rate of the APC gene in this group of Chinese FAP families was about 48.39%, and 4 novel mutations were detected. Frameshift mutation was the major mutation type in Chinese FAP and mainly located in exon 15.