[Constructing disease-specific cohorts of less common tumors based on surgical centers: reflections on the disease-specific cohort of biliary tract cancers].

The incidence of less common tumors is intermediate between rare tumors and high-prevalence tumors,while these less common tumors such as biliary tract cancers generate a significant regional health burden. The overall incidence of less common tumors is relatively low, and thus their clinical epidemiological studies face challenges such as recruitment difficulties,poor representation,and low standardization. Surgical center-based disease-specific cohorts have the advantages of case concentration,complete samples,and well-developed data,which are uniquely valuable in clinical epidemiological studies. Taking the disease-specific cohort of biliary tract cancers as an example,the authors combed through the relevant references and summarized the thinking in the practice of constructing disease-specific cohorts of less common tumors based on surgical centers. The architecture of the disease-specific cohort construction has been generalized as follows: the hardware includes a database, a biobank, and a platform of information synchronization, and the software follows the design principle of "high cohesion and low coupling". The authors also recommend an orderly expansion of study size and implementation of quality control through all segments of cohort construction, and hope that these reflections could provide a reference for similar disease-specific cohorts.