The Study Of Colorectal Cancer Screening Policies Based On The Personalized Characteristic

Colorectal cancer(CRC)is a common malignancy.It’s morbidity and mortality rank fourth and second in the developed country,respectively.With the change of diet structure,the morbidity and mortality of CRC are increasing year by year in our country.Cancer screening not only can reduce the life time risk of colorectal cancer,but also can make colorectal cancer to be detected at earlier stage.The screening policy of current guideline is based on the population’s analysis,they do not consider the characteristics of the patient.If the characteristic of the patient are considered in the screening policy,the accuracy of the test will be improved.In this paper,we propose finite-horizon,partially observable Markov decision process models to optimize the CRC screening program that combines both fecal occult blood test(FOBT)and colonoscopy for the average risk patient and colonoscopy for the high risk pa-tient.Our model incorporates information from prior screening history and individual risk factors,including age,body condition,life-style,etc.Compared to the existing guidelines,the proposed screening protocol increases expected total quality-adjusted life years and re-duces lifetime risk of developing CRC.Our analysis suggests more active screening between age 60 and 70.Some physicians suggest that average risk patient should use colonoscopy alone for CRC screening.Based on this suggestion,this paper builds partially observable Markov de-cision process(POMDP)model and optimizes the CRC screening which uses colonoscopy alone.Compared to the screening protocol that uses a combination of FOBT and colonoscopy,we demonstrate that when FOBT sensitivity is high,adding annual FOBTs can help identify CRC in a timely manner and increase expected total quality-adjusted life years(TQALYs)by reducing the number of colonoscopies required.This result has guiding significance in practice.The patient compliance is a serious problem in cancer screening.Many methods are used to improve the compliance rate,such as email,phone call,etc.However,the result is not ideal.We consider how to go through the colorectal cancer screening if the compliance rate is given.The simulation results illustrate that the patient whose compliance rate is low should be recommended more active colonoscopy.