Background: Seamless, cross-sector information flow is prerequisite for personalized oncology, spanning the full patient journey from primary care and specialist practices to molecular tumor boards (MTBs) and back into follow-up care. However, patient-centered information between clinical encounters is often insufficiently captured and integrated into routine decision-making. Objective: This paper aims to outline a pragmatic concept for integrating patient-reported outcomes (PROs) into cross-sector oncology workflows and to describe core process elements required for their routine use in clinical decision-making. Methods: We describe how PROs can be integrated via the German electronic patient record (ePA) and interoperable interfaces across primary care, specialist practices, oncology centers, and MTBs. As an operational framework, we propose a minimal four-step “action loop” consisting of (i) capture, (ii) contextualization, (iii) decision, and (iv) feedback, enabling structured use of PRO data within clinical workflows. Results: The proposed action loop addresses key implementation barriers by defining responsibilities, trigger points, and feedback mechanisms along the care pathway. This enables systematic use of PROs for longitudinal monitoring of symptom burden, functional status, and quality of life, thereby supporting continuously learning care that is patient centered. Conclusion: PROs can serve as a patient-centered compass along the oncology care pathway. The ePA has the potential to function as its cross-sector backbone—provided that capture and use of PROs is implemented in a standardized, interoperable, and workflow-integrated manner.