Colorectal cancer (CRC) screening programs have been established worldwide to prevent the development of CRC and to detect it early. CRC screening can be targeted at average- or high-risk... Show moreColorectal cancer (CRC) screening programs have been established worldwide to prevent the development of CRC and to detect it early. CRC screening can be targeted at average- or high-risk individuals. For average-risk individuals, the Dutch fecal immunochemical testing (FIT)-based CRC screening program was introduced in 2014, inviting all individuals aged 55-75 biennially. In Part I of this thesis, outcomes of the CRC screening program in the Netherlands are analyzed (i.e., CRC incidence, mortality, stage distribution, treatment). To optimize the balance between benefits and harms of CRC screening, risk stratification based on fecal hemoglobin concentrations after negative FIT could be the way forward. Part II describes the study protocol of a randomized controlled trail on personalized CRC screening and evaluates the information needs of the target population for personalized CRC screening strategies. For high-risk individuals, intensified CRC screening and surveillance may be needed, given these individuals have higher risk of developing CRC during their lifetime. Testicular cancer survivors treated with platinum-based chemotherapy can be considered high-risk individuals, as they have an increased risk of developing second primary gastrointestinal malignancies. Part III of this thesis explores the carcinogenesis of CRC and the yield of colonoscopy in these individuals. Show less
Ykema, B.L.M.; Bisseling, T.M.; Spaander, M.C.W.; Moons, L.M.G.; Biessen-van Beek, D. van der; Saveur, L.; ... ; Leerdam, M.E. van 2021
BackgroundTesticular cancer (TC) survivors have an increased risk of various second primary malignancies. A recent cohort study detected an increased risk of colorectal cancer (CRC) in TC survivors... Show moreBackgroundTesticular cancer (TC) survivors have an increased risk of various second primary malignancies. A recent cohort study detected an increased risk of colorectal cancer (CRC) in TC survivors treated with platinum-based chemotherapy with a hazard ratio of 3.9. CRC risk increased with higher cisplatin-dose. We know that colonoscopy surveillance in high-risk populations results in reduced incidence and mortality of CRC. TC survivors treated with platinum-based chemotherapy can potentially benefit from colonoscopy surveillance; however, to which extent is unknown. Furthermore, the pathogenesis of these secondary CRCs is unknown, and better insights into the carcinogenesis may affect surveillance decisions.MethodsThis prospective multicenter study will be performed in four Dutch hospitals. TC survivors are eligible if treated with >= 3 cycles of cisplatin before age 50. Colonoscopy will be performed >= 8 years after initial treatment (minimum and maximum ages at colonoscopy, 35 and 75 years, respectively). The primary aim of the study is the diagnostic yield of advanced neoplasia detected during colonoscopy. As secondary aim, we will evaluate the molecular profile of advanced colorectal neoplasia and will assess current platinum levels in blood and urine and correlate blood-platinum levels with prevalence of colorectal lesions. Furthermore, we will investigate effectiveness of fecal immunochemical testing (FIT) and burden of colonoscopy by two questionnaires. Demographic data, previous history, results of colonoscopy, hemoglobin level of FIT and results of molecular and platinum levels will be obtained. Yield of colonoscopy will be determined by detection rate of adenoma and serrated lesions, advanced adenoma detection rate and CRC detection rate. The MISCAN model will be used for cost-effectiveness analyses of CRC surveillance. With 234 participants undergoing colonoscopy, we can detect an absolute difference of 6% of advanced neoplasia with 80% power.DiscussionTC survivors treated with cisplatin-based chemotherapy can benefit from CRC surveillance. Evaluation of the diagnostic performance and patient acceptance of CRC surveillance is of importance to develop surveillance recommendations. Insight into the carcinogenesis of cisplatin-related advanced colorectal lesions will contribute to CRC prevention in the increasing number of TC survivors. The results may also be important for the many other cancer survivors treated with platinum-based chemotherapy.Trial registrationClinical Trials: NCT04180033, November 27, 2019, https://clinicaltrials.gov/ct2/show/NCT04180033. Show less
