After entering several patient, tumor, and treatment characteristics (age, tumor size, nodal involvement, grade, ER-/PR-status, multifocality, radiotherapy, chemotherapy, and endocrine therapy), it estimates the individual risk of developing a recurrence within the first 5 years after surgery, as well as conditional annual risks based on multivariable logistic regression models (Witteveen 2019; Witteveen 2015). This evidence concerns the gene ESR1 and neoplasm.