Abstract PS5-12-05: Cdk4/6 inhibitors in outpatient gynecological oncology: identification of implementation barriers and opportunities for improving their use in the practice

Abstract Background. The adjuvant therapy of breast cancer patients with cyclin-dependent kinase 4/6 inhibitors (CDKI) has been demonstrated to be remarkably efficacious, resulting in a notable enhancement in progression-free survival for patients afflicted with early-stage high-risk and locally advanced metastatic breast cancer. A notable benefit of CDKIs is their oral administration, which facilitates outpatient use. Nonetheless, the bulk of management of CDKI therapy in Germany occurs within the confines of hospitals, effectively impeding the access to treatment for a significant proportion of affected patients. The objective of this study is to ascertain the current state of knowledge and barriers to implementation, and subsequently, to develop support services that will enable an increase in the use of this class of drugs in gynecological practices. Methods. In a regional, multi-phase, anonymized, cross-sectional study, the level of knowledge, application experience, and implementation barriers of CDKI were recorded using a structured questionnaire among gynecological oncologists working in private practice in northern Germany. The data was evaluated to develop a structured practice guideline. In a subsequent survey, the impact of this practice guideline on willingness to treat was examined. In a third phase, the efficacy of structured training measures was examined using pre-post workshop evaluation with a structured questionnaire to quantify knowledge gain, self-confidence, and willingness to implement. Results. The initial survey revealed a discrepancy between the high level of interest in the use of CDKI (rather high/high: n =5 9/78; 75.6 %) and the level of knowledge regarding the subject (rather low/low: n = 63/78; 80.8 %). Despite the high level of interest, 50.1 % (no/rather no: n = 37/73) of practicing gynecologists reported a lack of confidence on using the drugs. The predominant rationale cited for the inadequate usage was a dearth of expertise in therapy management (n = 42/66; 63.6 %). To support these efforts, 69.9 % (n = 51/73) of participants indicated a preference for tailored information material. In response, a practice guide was developed for the use of CDKI, encompassing therapy management, dose adjustment in case of side effects, and practical application instructions. the findings of this study indicate that 73.0 % of gynecologists in private practice (n = 27/73) expressed a high level of confidence in independently treating their patients with CDKI, as indicated by their responses to the guide. The workshop evaluation revealed an initial low level of competence (mean overall score of 2.31 on a 5.0 scale), yet it demonstrated substantial impacts of structured training. A notable increase in interest was reported by 58.3 % (n = 7/12) of the participants, 41.7 % (n = 5/12) reported feeling better prepared for practical applications, and the overall workshop satisfaction was 3.67 on a 5.0 scale. The competence deficit was particularly pronounced in dosage management (2.09/5.0) and indication (2.15.5.0). Conclusion. The utilization of CDKI for the long-term adjuvant therapy of breast cancer presents a significant challenge in gynecological practices and is, as a result, employed only in limited capacities, despite the robust interest it has garnered. Primarily, the dearth of experience in its implementations constitutes an impediment that can be surmounted through the provision of information materials tailored to the outpatient section. The implementation of structured training measures, in conjunction with practice-oriented guidelines, has been demonstrated to be an effective intervention for enhancing competence and can measurably reduce implementation barriers, thereby contributing to the enhancement of outpatient care quality. Citation Format: M. Elessawy, N. Maass, M. Mackelenbergh, H. Le, . Cdk4/6 inhibitors in outpatient gynecological oncology: identification of implementation barriers and opportunities for improving their use in the practice [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS5-12-05.