Tobias Holderried ^1,2* Isabel Stasik ³ Marie-Therese Schmitz ⁴ Friederike Schmitz ^1,2 Tizian Meyer ⁵ Leonie Stauß ^6,7 Martin Kirschner ^2,8 Dirk Skowasch ⁹ Jennifer Landsberg ¹⁰ Matthias Schmid ⁴ Peter Brossart ^1,2 Prof. Dr. Dr. Martin Holderried ^11,6,7

• ¹ Department of Oncology and Hematology, Center of Integrated Oncology, University Hospital Bonn, Bonn, North Rhine-Westphalia, Germany
• ² Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), Aachen, Germany
• ³ Department of Ophthalmology, University Hospital Bonn, Bonn, North Rhine-Westphalia, Germany
• ⁴ Institute for Medical Biometry, Informatics and Epidemiology, University of Bonn, Bonn, North Rhine-Westphalia, Germany
• ⁵ Evangelische Kliniken, Waldkrankenhaus, Department for Internal Medicine, Bonn, Germany., Bonn, Germany
• ⁶ Department of Medical Development, Process- and Quality Management, Tuebingen University Hospital, Tuebingen, Germany, Tuebingen, Germany
• ⁷ Institute of Health Care & Public Management, Faculty of Business, Economics and Social Sciences, University of Hohenheim, Stuttgart, Baden-Württemberg, Germany
• ⁸ Department of Hematology, Oncology, Hemostaseology and Stem Cell Transplantation, University Hospital RWTH Aachen, Aachen, Germany
• ⁹ Department of Internal Medicine II, University Hospital Bonn, Bonn, North Rhine-Westphalia, Germany
• ¹⁰ Department of Dermatology and Allergology, University Hospital Bonn, Bonn, North Rhine-Westphalia, Germany
• ¹¹ eHealth Research Group, Department of Otolaryngology – Head and Neck Surgery, Tuebingen University Hospital, Tuebingen, Germany, Tuebingen, Germany

Background: The use of online information and communication is globally increasing in the healthcare sector. In addition to known benefits in other medical fields, possible specific potentials of eHealth lie in the monitoring of oncological patients undergoing outpatient therapy. Specifically, the treatment with immune checkpoint inhibitors (ICI) requires intensive monitoring due to various possible negative side effects. The present study explores cancer patients' perspectives on eHealth and demonstrates how eHealth applications, from the patients' point of view, can contribute to further improving outpatient immunotherapy. Methods and Findings: Our multicenter study was executed at the university hospitals in Bonn and Aachen. A structured questionnaire was distributed to patients receiving outpatient immunotherapy. Contents addressed were (1) the patients’ attitude towards eHealth applications, (2) the use of modern information and communications technologies (ICT) in (2a) everyday life and (2b) health-related information search including eHealth literacy, (3) the use of internet-enabled devices as well as (4) socio-demographic data. 164 patients were included in the study, of whom 39.0% were female and 61.0% male and the average age was 62.8 years. Overall, there was a high distribution of internet-enabled devices for everyday use and a great interest in integrating eHealth applications into outpatient immunotherapy. The assessment of eHealth potentials significantly depended on age. The younger participants demonstrated a broader use of modern ICT and a higher affinity for its use in outpatient immunotherapy. In some aspects, level of education and gender were also relevant factors influencing the patients’ view on eHealth. Conclusion: This study demonstrates the potential for further integration of eHealth applications into outpatient immunotherapy from the patients’ perspective. It indicates a dependency on age and educational level for the further integration of eHealth into patient care in oncology. Due to particular patient needs regarding age, level of education, gender and other subgroups, specific education and training as well as target-group specific digital health interventions are necessary to fully utilize the potentials of eHealth for outpatient immunotherapy. Future studies are required to specifically address target-group specific usability of eHealth applications and eHealth literacy, as well as to address information security and data protection.