Search

Objective To investigate the risk for second primary cancer in the hypopharynx and esophagus (SPC-HE) among individuals with an initial oral/oropharyngeal cancer. Materials and methods Mass screening data from Taiwan (2004-2009) included individuals who were ≥18 years old and smoked cigarettes and/or chewed betel quid. Occurrence of SPC-HE was monitored until December 31, 2014. Results were expressed as adjusted relative risk (aRR) and 95% confidence interval (CI). Results One hundred and fifty-eight out of 4,494 subjects with oral cancer developed SPC-HE (incidence rate: 6.47 per 1,000 person-years). Relative to patients with primary cancers in the lip, the risk of an SPC-HE was higher in patients with primary cancers in oropharynx (aRR: 19.98, 95% CI: 4.72-84.55), floor of mouth (aRR: 12.13, 95% CI: 2.67-55.15), and hard palate (aRR: 7.31, 95% CI: 1.65-32.37), but not in patients with cancers in tongue (aRR: 3.67, 95% CI: 0.89-15.17) or gum (aRR: 3.99, 95% CI: 0.92-17.35). Regression analyses also showed the risk of an SPC-HE was greater in alcohol drinkers than those who did not (aRR: 1.65, 95% CI: 1.10-2.48). Conclusions Compared with the initial cancer in the lip, patients with a cancer in the oropharynx, floor of mouth, and hard palate had a higher risk for the SPC-HE.

Objectives The present study was to investigate the association between fecal hemoglobin (f-Hb) concentration and oral cancer and its precursor, oral potentially malignant disorders (OPMD). Methods We used a population-based longitudinal cohort study data based on both Taiwanese nationwide oral and colorectal cancer screening programs implemented between 2004 and 2009. The total of 235,234 smokers and/or betel-quid chewers aged 50 to 69 years free of oral cancer and OPMD at entry were followed up over time to quantify the association between baseline f-Hb concentration on newly diagnosed oral cancer and OPMD. Results The risk of OPMD increased with baseline f-Hb in a dose manner, yielding a statistically significant elevated risk of developing OPMD in parallel with the incremental concentration of f-Hb (adjusted hazard ratios = 0.99, 1,11, 1,07, 1,57, and 1,63 for f-Hb categories of 1-9, 10-19, 20-49, 50-89, and ≥90 µg Hb/g, respectively, as compared with the reference group (low and undetectable f-Hb concentrations)) However, there was lacking of a statistical significance for the corresponding association regarding the risk of oral cancer, which is possibly due to sparse cases given a shorter follow-up time. Conclusion We discovered that f-Hb concentration was positively related to the risk of OPMD. f-Hb can be used as a biomarker for early detection of OPMD.

BACKGROUND To reduce oral cancer mortality, an organized, population-based screening program for the early detection of oral premalignancy and oral cancer was designed for high-risk individuals with habits of betel quid chewing, cigarette smoking, or both. The objective of this report was to evaluate the long-term effectiveness of this program in reducing the incidence of advanced disease and deaths from oral cancer. METHODS A nationwide, population-based screening program for oral cancer has been conducted in Taiwan since 2004. Residents aged ≥ 18 years with oral habits of cigarette smoking and/or betel quid chewing were invited. The standardized mortality ratio method was used to compare the observed numbers of advanced oral cancers and deaths from oral cancer among screening attendees with the expected numbers derived from mortality among nonattendees. An intention-to-treat analysis of the relative rate of reductions in advanced-stage oral cancers and oral cancer mortality also was conducted. RESULTS The overall screening rate was 55.1%. The relative risk of death from oral cancer was 0.53 (95% confidence interval [CI], 0.51-0.56) as a result of screening compared with the expected risk of oral cancer deaths in the absence of screening. The corresponding relative risk was 0.74 (95% CI, 0.72-0.77) after adjusting for self-selection bias. The relative risk of advanced oral cancer for the screened group versus the nonscreened group was 0.62 (95% CI, 0.59-0.64), which increased to 0.79 (95% CI, 0.76-0.82) after adjustment for self-selection bias. CONCLUSIONS An organized, population-based oral cancer screening program targeting more than 2 million Taiwanese cigarette smokers and/or betel quid chewers demonstrated the effectiveness of reducing stage III or IV oral cancers and oral cancer mortality. These evidence-based findings corroborate and support the screening strategy of oral visual inspection for the prevention of oral cancer among high-risk individuals in areas with a high incidence of oral cancer. Cancer 2017;123:1597–1609. © 2017 American Cancer Society.

Background Risk-stratified screening for prostate cancer (PCa) with prostate-specific antigen (PSA) testing incorporating genetic variants has received some attention but has been scarcely investigated. We developed a model to stratify the Finnish population by different risk profiles related to genetic variants to optimize the screening policy. Methods Data from the Finnish randomized controlled trial on screening for PCa with PSA testing were used to estimate a six-state Markov model of disease progression. Blood samples from Finnish men were used to assess the risk of PCa related to three genetic variants (rs4242382, rs138213197, and rs200331695). A risk score-based approach combined with a series of computer simulation models was applied to optimize individual screening policies. Results The 10-year risk of having progressive prostate cancer detected ranged from 43% in the top 5% risk group to approximately 11% in the bottom half of the population. Using the median group, with screening every four years beginning at 55 years-old, as the reference group, the recommended age beginning screening was approximately 47 years-old for the top 5% risk group and 55 years-old for those in the lower 60% risk group. The recommended interscreening interval has been shortened for individuals in the high risk group. The increased availability of genomic information allows the proposed multistate model to be more discriminating with respect to risk stratification and the suggested screening policy, particularly for the lowest risk groups­.­­ Conclusions A multi-state genetic variant-based model was developed for further application to population risk stratification to optimize the interscreening interval and the age at which to begin screening for PSA. A small sub-group of the population is likely to benefit from more intensive screening with early start and short interval, while half of the population is unlikely to benefit from such protocol (compared with four-year interval after age 55 years). Prostate 75:825–835, 2015. © 2015 Wiley Periodicals, Inc.

Background and purpose: To investigate the relationships of diabetic neuropathy to all-cause and diabetes-related mortality in patients with type 2 diabetes after controlling for significant correlates. Methods: We examined 326 patients diagnosed as diabetic polyneuropathy by nerve conduction study in Keelung city, Taiwan, in 2002 and followed them up to ascertain the cause and date of death until the end of 2006. The cause and date of death were recorded for the deceased patients. Information on significant correlates in association with diabetic polyneuropathy and all-cause and diabetes-related mortality was also collected. Results: With median follow-up time of 62.28 months, 44 patients with type 2 diabetes died. The cause of death related to diabetes accounted for 59% (n = 26) of the deceased. Univariate analysis shows that the presence of diabetic neuropathy confers higher risk for all-cause mortality (hazard ratio [HR] = 4.88) and mortality from diabetes (HR = 6.58). The significant finding still persisted after adjustment for age, gender, blood pressure, smoking, history of cardiovascular/cerebrovascular disease, duration of diabetes, waist circumference, fasting plasma glucose, total cholesterol, hemoglobin, and creatinine (adjusted HR = 4.44 for all-cause death and adjusted HR = 11.82 for diabetes-related mortality, respectively). Conclusions: Diabetic polyneuropathy was an independent predictor for all-cause and diabetes-related mortality. The presence of neuropathy together with other significant prognostic factors is informative to predict all-cause death and death from diabetes-related disease for patients diagnosed as type 2 diabetes.

Rationale, aims and objectives Population-based randomized controlled trials (RCTs) often involve enormous costs and long-term follow-up to evaluate primary end points. Analytical decision-simulated model for sample size and effectiveness projections based on primary and surrogate end points are necessary before planning a population-based RCT. Method Based on the study design similar to two previous RCTs, transition rates were estimated using a five-state natural history model [normal, preclinical detection phase (PCDP) Dukes' A/B, PCDP Dukes' C/D, Clinical Dukes' A/B and Clinical Dukes' C/D]. The Markov cycle tree was assigned transition parameters, variables related to screening and survival rate that simulated results of 10-year follow-up in the absence of screening for a hypothetical cohort aged 45–74 years. The corresponding screened arm was to simulate the results after the introduction of population-based screening for colorectal cancer with fecal occult blood test with stop screen design. Results The natural course of mean sojourn time for five-state Markov model were estimated as 2.75 years for preclinical Dukes' A/B and 1.38 years for preclinical Dukes' C/D. The expected reductions in mortality and Dukes' C/D were 13% (95% confidence intervals: 7–19%) and 26% (95% confidence intervals: 20–32%), respectively, given a 70% acceptance rate and a 90% colonoscopy referral rate. Sample sizes required were 86 150 and 65 592 subjects for the primary end point and the surrogate end point, respectively, given an incidence rate up to 0.0020 per year. Conclusions The sample sizes required for primary and surrogate end points and the projection of effectiveness of fecal occult blood test for colorectal cancer screening were developed. Both are very important to plan a population-based RCT.

Objectives This study is to identify an optimal cut-off for two-stage breast cancer screening making allowance for variation of the baseline incidence rate and utility values between sensitivity and specificity. Methods We used data from a two-stage breast cancer screening of Taiwanese women aged 50–69 years for whom risk stratification was based on a composite risk score (conventional risk factors); subjects with a risk score greater than the cut-off score were screened using mammography. The Bayesian posterior risk for breast cancer was computed by incorporation of the baseline incidence rate and the risk score. Bayes' maximum utility decision rule was then developed to determine the optimal screening cut-off. Results With a risk score of −9 applied to the current two-stage breast cancer screening programme, we could detect one breast cancer case for every 1406 women. Given different predetermined risks, the selected cut-offs were −9 for 1:1200, −8 for 1:800, −4 for 1:600, −1 for 1:400 and 3 for 1:200 for women aged 50–59 years. When the regret utility ratio of positive predictive value to negative predictive value was set at 1:10, the specificity and sensitivity were 58.5% and 70.4%, respectively, and the optimal cut-off was −5.5. When the ratio was set at 10:1, the sensitivity and specificity were 75.5% and 57.1%, respectively, and the optimal cut-off value was −7.5. Conclusions This study demonstrates that Bayes' maximum utility decision rule can be used to determine optimal cut-off values for two-stage breast cancer screening in countries or areas with lower or intermediate incidence of breast cancer.

Background: Although the effect of betel quid chewing and smoking on oral cancer has been well documented, both influences, dose and duration during life time, on multistate progression of oral pre-malignancy are hardly addressed. Methods: By recruiting a group of male chewers from different occupation groups, we modeled the effects of both duration and quantity of betel quid chewing and smoking on annual incidence rate of developing leukoplakia and average dwelling times (ADTs) staying in leukoplakia and erythroleukoplakia. Results: The annual incidence rate (per year) of leukoplakia was estimated as 0.35% (95% CI: 0.22–0.48%). The ADTs were 24 years for leukoplakia and 7 years for erythroleukoplakia. Annual incidence rate of leukoplakia with high consumption and long duration of betel quid and smoking was higher. Both quantity and duration of smoking and betel quid chewing play minor roles in the influence of ADT. The risks of developing oral cancer after 20 years of follow-up were 42.2% for leukoplakia and 95.0% for erythroleukoplakia. Conclusion: The effects of betel quid chewing and smoking on multistate progressions between oral pre-malignancies were elucidated. These results can be applied to predict long-term risk of malignant transformation varying with different duration and quantity of betel quid and cigarette.