Comparison of multiple statistical models for the development of clinical prediction scores to detect advanced colorectal neoplasms in asymptomatic Thai patients.

ABSTRACT: A good clinical prediction score can help in the risk stratification of patients with colorectal cancer (CRC) undergoing colonoscopy screening. The aim of our study was to compare model performance of binary logistic regression (BLR), polytomous logistic regression (PLR), and classification and regression tree (CART) between the clinical prediction scores of advanced colorectal neoplasia (ACN) in asymptomatic Thai patients.We conducted a cross-sectional study of 1311 asymptomatic Thai patients to develop a clinical prediction model. The possible predictive variables included sex, age, body mass index, family history of CRC in first-degree relatives, smoking, diabetes mellitus, and the fecal immunochemical test in the univariate analysis. Variables with a P value of .1 were included in the multivariable analysis, using the BLR, CART, and PLR models. Model performance, including the area under the receiver operator characteristic curve (AUROC), was compared between the model types.ACN was diagnosed in 53 patients (4.04%). The AUROCs were not significantly different between the BLR and CART models for ACN prediction with an AUROC of 0.774 (95% confidence interval [95% CI]: 0.706-0.842) and 0.765 (95% CI: 0.698-0.832), respectively (P = .712). A significant difference was observed between the PLR and CART models in predicting average to moderate ACN risk with an AUROC of 0.767 (95% CI: 0.695-0.839 vs AUROC 0.675 [95% CI: 0.599-0.751], respectively; P = .009).The BLR and CART models yielded similar accuracies for the prediction of ACN in Thai patients. The PLR model provided higher accuracy for ACN prediction than the CART model.

Association between Low Fruit and Vegetable Consumption and Colorectal Polyps in Thailand.

OBJECTIVE: This study aimed to evaluate the association between low fruit and vegetable consumption and colorectal polyps. METHODS: A retrospective study was conducted among 1,228 participants aged 50-65 years who completed 2-time colonoscopy exams at the first and the fifth year of a colorectal screening program. Consuming less than one serving of fruit and vegetable daily was rated as low. Colorectal polyps from colonoscopy findings were recognized in 3 types: hyperplastic, low risk and high risk adenomatous polyps. RESULTS: The findings demonstrated high prevalence of low fruit (93.6%) and low vegetable (85.8%) consumption. Exercising individuals were more likely to consume both fruit (OR 2.28, 95%CI 1.42-3.65) and vegetable (OR 1.40, 95%CI 1.00-1.96), while smoking history individuals tended to consume vegetable (OR 2.08, 95%CI 1.22-3.55). Low fruit consumption was strongly associated with high risk adenomatous polyps (OR 4.39, 95%CI 2.40-8.03), while low vegetable consumption was distinctively associated with low risk (OR 6.26, 95%CI 4.11-9.55) and high risk adenomatous polyps (OR 8.64, 95%CI 5.30-14.09). CONCLUSION: This study provides additional evidence of the association between low fruit and vegetable consumption and colorectal polyps. Enhancing people fiber eating behavior may help preventing colorectal cancer risk.

Value of FDG PET/Contrast-Enhanced CT in Initial Staging of Colorectal Cancer - Comparison with Contrast-Enhanced CT.

BACKGROUND: FDG PET/CT is at an equivocal stage to recommend for staging of colorectal cancer as compared to contrast-enhanced CT (ceCT). This study was intended to evaluate the value of FDG PET/ceCT in colorectal cancer staging as compared to ceCT alone. MATERIALS AND METHODS: PET/ceCT was performed for 61 colorectal cancer patients who were prospectively enrolled in the study. Three patients were excluded due to loss to follow-up. PET/ceCT findings and ceCT results alone were read separately. The treatment planning was then determined by tumor board consensus. The criteria for T staging were determined by the findings of ceCT. Nodal positive by PET/ceCT imaging was determined by visual analysis of FDG uptake greater than regional background blood pool activity. The diagnostic accuracy of T and N staging was determined only in patients who received surgery without any neoadjuvant treatment. RESULTS: Of 58 patients, there were 40 with colon cancers including sigmoid cancers and 18 with rectal cancers. PET/ceCT in pre-operative staging detected bone metastasis and metastatic inguinal lymph nodes (M1a) that were undepicted on CT in 2 patients (3%), clearly de ned 19 equivocal lesions on ceCT in 18 patients (31%) and excluded 6 metastatic lesions diagnosed by ceCT in 6 patients (10%). These resulted in alteration of management plan in 15 out of the 58 cases (26%) i.e. changing from chemotherapy to surgery (4), changing extent of surgery (9) and avoidance of futile surgery (2). Forty four patients underwent surgery within 45 days after PET/CT. The diagnostic accuracy for N staging with PET/ceCT and ceCT alone was 66% and 48% with false positive rates of 24% (6/25) and 76% (19/25) and false negative rates of 47% (9/19) and 21% (4/19), respectively. All of the false negative lymph nodes from PET/ceCT were less than a centimeter in size and located in peri-lesional regions. The diagnostic accuracy for T staging was 82%. The sensitivity of the peri-lesional fat stranding sign in determining T3 stage was 94% and the specificity was 54%. CONCLUSIONS: Our study suggested promising roles of PET/ceCT in initial staging of colorectal cancer with better diagnostic accuracy facilitating management planning.

High prevalence of advanced colorectal neoplasia in the Thai population: a prospective screening colonoscopy of 1,404 cases.

BACKGROUND: Increasing morbidity and mortality from colorectal cancer is evident in recent years in the developing Asian nations. Particularly in Thailand and most neighbouring low-income countries, screening colonoscopy is not yet recommended nor implemented at the national policy level. METHODS: Screening colonoscopy was offered to 1,500 healthy volunteers aged 50-65 years old who were registered into the program between July 2009 and June 2010. Biopsy and surgery was performed depending on the identified lesions. Fecal immunochemical tests (FIT) were additionally performed for comparison with colonoscopy. RESULTS: There were 1,404 participants who underwent colonoscopy. The mean age of the cohort was 56.9 ± 4.2 years and 69.4 % were females. About 30 % (411 cases) of all colonoscopies had abnormal colonoscopic findings, and of these, 256 cases had adenomatous polyps. High risk adenomas (villous or tubulovillous or high grade dysplasia or size > 1 cm or > 3 adenomatous polyps) were found in 98 cases (7 %), low risk adenoma in 158 cases (11.3 %), and hyperplastic polyps in 119 cases (8.5 %). Eighteen cases (1.3 %) had colorectal cancer and 90 % of them (16 cases) were non-metastatic including five stage 0 cases, seven stage I cases, and four stage IIA cases. Only two cases had metastasis: one to regional lymph nodes (stage IIIB) and another to other organs (stage IVA). The most common cancer site was the distal intestine including rectum (7 cases, 38.9 %) and sigmoid colon (7 cases, 38.9 %). Ten colorectal cancer cases had positive FIT whereas 8 colorectal cancer cases were FIT-negative. The sensitivity and specificity of FIT was 55.6 % and 96.2 %, respectively, while the positive predictive value was 16.4 % and negative predictive value was 99.4 %. The overall survival of colorectal cancer cases at 5-year was 83.3 %. CONCLUSION: High prevalence of colorectal cancer and high-risk adenoma was found in the Thai population aged 50-65 years old by screening colonoscopy. FIT was not sensitive enough to detect colorectal cancer in this asymptomatic cohort. Integration of screening colonoscopy into the national cancer screening program should be implemented to detect early cases of advanced colorectal neoplasia and improve survival of colorectal cancer patients in Thailand.

Hydrocolonic sonography: a complete colorectal evaluation technique with preliminary results.

BACKGROUND: Hydrocolonic ultrasound (HUS) is a low-cost imaging modality as compared with standard colonoscopy. However, HUS is not popular in the clinical setting due to its somewhat complicated technique of examination and inability to visualize the rectum. We developed a technique to overcome these limitations. METHODS: Ten patients with cancer-suggestive symptoms and 70 asymptomatic patients were included in this study. All patients underwent HUS, with the technique described herein, before colonoscopy on the same day. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated. RESULTS: There were 30 men and 50 women with a mean age of 60.9 ± 7.3 (SD) years. Thirteen polyps with a size ≥0.6 cm (four lesions size 0.6 to 0.9 cm and nine lesions size ≥1 cm) were detected by colonoscopy. The detection rate of lesions by HUS was 25% for polyps size 0.6-0.9 cm and 89% for lesions size ≥1 cm in size. Three lesions were missed in the sigmoid colon, one in the transverse colon, and one in the rectum. CONCLUSIONS: HUS is a low-cost and noninvasive procedure for colorectal study. This technique has the potential to be used for the detection of colorectal cancer and polyps.