Prevalence and Incidence of Peutz–Jeghers Syndrome and Juvenile Polyposis Syndrome in Japan: A Nationwide Epidemiological Survey in 2022

ABSTRACT Background and Aim Peutz–Jeghers syndrome (PJS) and juvenile polyposis syndrome (JPS) are autosomal dominant diseases associated with high cancer risk. In Japan, knowledge about the prevalence and incidence of PJS and JPS is lacking despite being crucial for providing appropriate medical support. We aimed to determine the prevalence and incidence of these diseases. Methods In 2022, a nationwide questionnaire survey was conducted to determine the number of patients with PJS or JPS by sex and the number of newly confirmed cases from 2019 to 2021. The target facilities included gastroenterology, pediatrics, and pediatric surgery departments, which were stratified into seven classes on the basis of the total number of beds. We randomly selected target facilities using different extraction rates in each class, resulting in 1748/2912 facilities (extraction rate: 60%) as the final sample. We calculated the estimated number of patients using the response and extraction rates. Results A total of 1077 facilities responded to the survey. The estimated numbers of patients with PJS and JPS were 701 (95% confidence interval [CI]: 581–820) and 188 (95% CI: 147–230), respectively. The 3‐year period prevalences of PJS and JPS were 0.6/100000 and 0.15/100000, whereas the incidences in 2021 were 0.07/100000 and 0.02/100000, respectively. Male patients constituted 53.5% and 59.6% in the PJS and JPS groups, respectively. Conclusions We determined the prevalence and incidence of PJS and JPS in Japan for the first time. Further research is needed to obtain more detailed information, including the clinical differences and outcomes in Japan.