Prioritisation of colonoscopy services in colorectal cancer screening programmes to minimise impact of COVID-19 pandemic on predicted cancer burden: A comparative modelling study

Objectives

Colorectal cancer (CRC) screening with a faecal immunochemical test (FIT) has been disrupted in many countries during the COVID-19 pandemic. Performing catch-up of missed screens while maintaining regular screening services requires additional colonoscopy capacity that may not be available. This study aimed to compare strategies that clear the screening backlog using limited colonoscopy resources.

Methods

A range of strategies were simulated using four country-specific CRC natural-history models: Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) and MIcrosimulation SCreening ANalysis for CRC (MISCAN-Colon) (both in the Netherlands), Policy1-Bowel (Australia) and OncoSim (Canada). Strategies assumed a 3-month screening disruption with varying recovery period lengths (6, 12, and 24 months) and varying FIT thresholds for diagnostic colonoscopy. Increasing the FIT threshold reduces the number of referrals to diagnostic colonoscopy. Outcomes for each strategy were colonoscopy demand and excess CRC-related deaths due to the disruption.

Results

Performing catch-up using the regular FIT threshold in 6, 12 and 24 months could prevent most excess CRC-related deaths, but required 50%, 25% and 12.5% additional colonoscopy demand, respectively. Without exceeding usual colonoscopy demand, up to 60% of excess CRC-related deaths can be prevented by increasing the FIT threshold for 12 or 24 months. Large increases in FIT threshold could lead to additional deaths rather than preventing them.

Conclusions

Clearing the screening backlog in 24 months could avert most excess CRC-related deaths due to a 3-month disruption but would require a small increase in colonoscopy demand. Increasing the FIT threshold slightly over 24 months could ease the pressure on colonoscopy resources.

Benefits and Harms of Gastric Cancer Screening and Prevention in Japan: A Microsimulation Modeling Analysis

Background: In 2016, gastric cancer is the second leading cause of cancer mortality worldwide. Globally, Japan and Korea are the only two countries implementing national screening program for gastric cancer. South Korea launched a biennial national -endoscopic screening program in 1999, which demonstrated a 47% reduction in gastric cancer mortality compared with no screening. In 2015, endoscopic screening was recommended by the Japanese Guideline for Gastric Cancer Screening. Currently, Japan's screening policy recommends endoscopic screening every 2 to 3 years for individuals aged 50 or above. Aim: This study aims to quantify the potential impacts of Japan's current national endoscopic screening policy and other alternative endoscopic screening options, and to identify a set of efficient endoscopic screening strategies for the current population of Japan. Methods: A microsimulation model of intestinal-type noncardia gastric adenocarcinoma was developed to simulate a virtual population with similar risk profile and life expectancy to the actual population of Japan. The model was calibrated and validated to the nationally-representative data from vital statistics and population-based cancer registries. The baseline scenario was modeled to project the current trend of gastric cancer. Variations among age of initiation (40, 45, 50, and 55), age of termination (75, 80, and 85), and screening interval (2, 5, 10, and 15 years) resulted in 39 unique endoscopic screening strategies for evaluation. In addition, the following three existing screening scenarios were included for analysis: the current screening program in Japan (screening every two or three years from age 50 years, with no termination) and Korea (biennial screening from age 40 years, with no termination). In total, 42 unique endoscopic screening strategies were simulated. Full adherence for all screening scenarios were assumed. Results: In comparison with baseline scenario, endoscopic screening strategies provided 43 to 203 life-years gained per 1000 individuals. The number of lifetime endoscopies per 1000 individuals ranged from 2281 to 28,635. The complications caused by screening were from 6 to 77 per 1000 individuals. The lifetime number of false-positive results ranged from 381 to 4941 per 1000 individuals. Scenarios simulating the current national endoscopic screening program in Japan and Korea fell below the efficient frontier. Under full adherence assumption, the most advantageous endoscopic screening strategy among evaluated scenarios is screening from age 40 to 80 years every 5 year. Conclusion: In this microsimulation modeling study with full adherence assumption, the findings suggest that the current national endoscopic screening program for gastric cancer in Japan might not be the most efficient screening option under benefit-to-harm consideration. The finding underpins the need for further investigation to bring up an efficient and cost-effective endoscopic screening program in Japan.

Association between decreasing trend in the mortality of adult T-cell leukemia/lymphoma and allogeneic hematopoietic stem cell transplants in Japan: analysis of Japanese vital statistics and Japan Society for Hematopoietic Cell Transplantation (JSHCT)

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell neoplasm with a very poor outcome. However, several studies have shown a progress in the treatment. To evaluate the effect of the progress in the treatment of ATLL in a whole patient population, we used vital statistics data and estimated age-adjusted mortality and trends in the mortality from 1995 to 2009. Since allogeneic hematopoietic stem-cell transplantation (allo-HSCT) has been introduced as a modality with curative potential during study period, we also evaluated the association of the annual number of allo-HSCT and the trend of the mortality of ATLL. Endemic (Kyushu) and non-endemic areas (others) were evaluated separately. Significance in the trend of mortality was evaluated by joinpoint regression analysis. During the study period, a total of 14 932 patients died of ATLL in Japan, and mortality decreased significantly in both areas (annual percent change (95% confidence interval (CI)): Kyushu, −3.1% (−4.3, −1.9); others, −3.4% (−5.3, −1.5)). This decreasing trend in mortality seems to be associated with an increase in the number of allo-HSCTs (Kyushu, R-squared=0.70, P=0.003; and others, R-squared=0.55, P=0.058). This study reveals that the mortality of ATLL is now significantly decreasing in Japan and this decreasing trend might be associated with allo-HSCT.

Smoking habits in relation to reproductive events among Japanese women: findings of the Japanese Nurses' Health Study

OBJECTIVE

The purposes of this study were to examine smoking habits in relation to the reproductive events of pregnancy and menopause and clarify the reasons for smoking cessation among ex-smokers.

METHOD

This is a cross-sectional study based on a baseline survey of a prospective cohort study. From 2001 to 2007, a self-administered questionnaire survey was conducted on 49,927 female nurses from all 47 prefectures in Japan. Logistic regression models were used to estimate age-adjusted odds ratios.

RESULTS

Of the respondents, 17.2% were current smokers, 11.6% were ex-smokers and 69.8% had never smoked. The prevalence of smoking during pregnancy was 7.8%. Among ex-smokers, 30.3% gave "reproductive events" as their reason for smoking cessation. Current smoking and the number of cigarettes smoked per day before menopause were significantly related to onset of menopause.

CONCLUSION

Women's smoking habits have mutual relationships with reproductive events such as pregnancy and menopause. Although "reproductive events" were an important reason for smoking cessation among women, 7.8% of women still smoked during pregnancy. Smoking was correlated with onset of menopause. Support for smoking cessation is an important healthcare issue throughout women's lifetimes.

Neural substrates for the recognition of newly learned faces: a functional MRI study

Face recognition is critical to the appreciation of our social and physical relations. Functional magnetic resonance imaging (fMRI) was used to identify brain regions involved in the recognition of newly learned faces. Two experiments were conducted. Experiment 1 contrasted a fixation control task with a face recognition task in which subjects were exposed solely to previously viewed faces (all-target). Experiment 2 compared a fixation control with another face recognition task in which subjects were presented with both novel and viewed faces (half-target). Compared to the fixation control, the all-target face recognition was associated with activation in the bilateral occipital and occipitotemporal regions, whereas the half-target face recognition produced activation in the right parietal and prefrontal regions, in addition to the occipital and occipitotemporal. The all-target minus half-target comparison revealed significant activation in the bilateral fusiform gyrus, suggesting stronger fusiform activity during the all-target than the half-target face recognition. The half-target minus all-target comparison showed significant activation in the superior and inferior parietal lobules and several regions in the right frontal lobe. These findings demonstrated that the bilateral fusiform gyrus is involved, not only in face perception, but in a certain aspect of face recognition memory and that this aspect is related to the actual recognition of previously viewed faces rather than the processing of novel ones, which results are consistent with previous lesion work. The right parietal and frontal regions, in contrast, are differentially more associated with the processes related to the detection of novel faces or retrieval effort.