The ''Hamburg Life After Cancer Program'': Development, Implementation and Evaluation of a Structured Survivorship Program - Study Protocol of a Hybrid Effectiveness-Implementation Study

Background: Advances in multimodal oncological treatment have improved survival, resulting in a growing population of cancer survivors. Yet, many survivors experience physical and psychosocial late and long-term effects after completing active cancer treatment, highlighting the need for follow-up care that extends beyond tumor surveillance. However, structured survivorship programs addressing survivors' broader needs and evidence on their effectiveness and implementation remain limited. Methods: This prospective, single-center, single-arm intervention study with an external control cohort aims to develop, implement, and systematically evaluate the Hamburg Life After Cancer Program. Applying a hybrid type 2 effectiveness-implementation design, the primary aim is to improve health-related quality of life (HRQoL) among program participants (n = 500), namely cancer survivors aged 18-65 years who completed primary treatment. Secondary objectives include improvements in various bio-psycho-social outcomes, as well as an exploratory comparison of HRQoL with an external control cohort receiving usual care (n = 250). Outcomes are assessed at baseline, 26 weeks and 52 weeks. Implementation is evaluated following a mixed-methods approach. The intervention comprises patient navigation, multidimensional assessment, survivorship consultations, an interdisciplinary survivorship board, individualized care plans, a survivorship handbook, educational sessions and peer-support. All study phases are guided by a participatory research approach involving patients and experts. Discussion: Findings will contribute to the development of needs-based, feasible survivorship care models, improving HRQoL and providing holistic support for cancer survivors. The study design enables timely translation of the program into clinical practice and robust assessment of its effectiveness and implementation. However, the non-randomized design may limit causal inference and cannot fully exclude residual confounding or selection bias despite statistical adjustment. If shown to be effective and feasible, the program may serve as a standardized model for structured survivorship care in Germany. Trial Registration: Clinical trial registration number: DRKS00035126, German Clinical Trial Register (date of registration: 27 August 2025). Keywords: cancer survivorship; follow-up care; hybrid effectiveness-implementation design; HRQoL; patient navigation; survivorship program, real-world implementation.