PCN124 - Individual Risk Profiling For Breast Cancer Recurrence: Towards Tailored Follow-Up Schemes

Abstract

Current international guidelines for breast cancer follow-up are not specific to individual risk of local regional recurrences. Instead, for personalised follow-up it is required to have more precise estimates of local regional recurrence probability as a function of time. The objective of this study is to identify prognostic factors, and to quantify individualized and time dependent local regional recurrence risk rates. Prognostic factors for local regional recurrence of breast cancer were identified due to a three-step funnel approach, including: scoping literature review, expert consultation and stepwise multivariate regression analysis. Quantification of the prognostic value of each risk factor was performed with a regression model based on a five-year dataset of women diagnosed with breast cancer in the Netherlands in 2005 or 2006 (n=17762). Six-month interval risk probabilities were derived from regression estimates by calculating coefficients of the prognostic factors. Eight prognostic factors were identified, including: age, tumour size, multifocality, gradation, adjuvant chemo-, adjuvant radiation-, hormonal therapy and triple negative status. Expected inter-patient variability was elucidated by average, and high risk example patient types with local regional, non-uniform distributed, recurrence risks of 5.2% and 12% over a five-year period. It is concluded that local regional recurrence risks are not distributed uniformly, and time depended, over the five-year follow-up period. The calculated prognostic value of the factors enables quantification of risks for local regional recurrences on six-month time intervals for the individual patient. Implicating improved allocation of hospital capacities and resources, local regional recurrence risk profiling is a first step towards tailored follow-up in breast cancer care.