Abstract PS5-08-12: Start of SerMa - EUBREAST 5 (Seroma of the Mammary Gland) study (NCT05899387)

Abstract Background: The standard local therapy for breast cancer is surgery. Postoperative seroma formation is one of the most common and serious complications after breast surgery for primary breast cancer, especially in patients undergoing mastectomy with or without implant-based breast reconstruction. Seromas may lead to infections and wound dehiscence, which can result in loss of reconstruction, ugly scars and poor cosmetic outcome.. To date, the cause of seroma development has not yet been clarified. Trial Design: The main objective of the multicenter SerMa study is to identify a subgroup of patients with an increased risk of developing seromas based on immunological or inflammatory markers in a planned cohort of 2200 subjects. The study is designed as international, prospective cohort study in cooperation with the EUBREAST Network (European Breast Cancer Research Association of Surgical Trialists). articipating study groups are AGO-B, AWOgyn and OPBC. Patients with primary breast cancer or ductal carcinoma in situ (DCIS) planned for mastectomy with or without reconstruction can participate in this study (study group 1 and 2). Study group 3 includes patients at high risk for breast cancer planned for risk-reducing subcutaneous mastectomy and implant-based reconstruction. Study group 4 includes healthy women with implant insertion for exclusively cosmetic reasons. Currently, the logistics phase with 50 patients has been completed, which was carried out to optimize the preservation of blood samples and seroma fluid. Primary endpoints: To achieve the primary endpoint - the identification of a patient group with an elevated risk of developing a seroma - it is planned to examine the groups with and without postoperative seroma formation regarding immunological markers in seroma fluid as well as in blood samples. In addition, local microbiome analyses, as well as tumor analyses with focus on microenvironment will be performed to differentiate possible carcinoma-specific immunological processes. Secondary endpoints: To answer the question whether differences are caused by immunological or cancer-related reasons, groups with and without postoperative seroma formation as well as groups with or without breast cancer are compared. Current status of the study: Following the current finalization of the logistics phase the study is open for recruitment, The study is currently expanding worldwide. Target accrual: 2200 participants in total. Citation Format: N. Ditsch, M. Koepke, N. Pochert, U. Jeschke, M. Schneider, M. Reiger, C. Traidl-Hoffmann, Y. Masannat, A. Mattmer, S. Hunstiger, J. Sagasser, C. Dannecker, M. Wild, C. Hinske, M. Hauptmann, S. Hartmann, H. Kahl, D. Krug, N. Krawczyk, K. Stemmer, D. Rezek, A. Raue, M. Gasparri, R. Reitsamer, J. Jelinska, G. Cakmak, E. Bonci, R. Wuerstlein, V. Fink, V. Bjelic-Radisic, M. Thill, C. Heitmann, W. Weber, E. Stickeler, A. Lebeau, P. A. Fasching, H. Kolberg, T. Reimer, L. Bauer, U. Beckmann, B. Aktas, S. Hasmueller, U. Schlembach, R. Di Micco, J. De Boniface, O. Gentilini, M. Untch, T. Kühn, M. Banys-Paluchowski. Start of SerMa - EUBREAST 5 (Seroma of the Mammary Gland) study (NCT05899387) [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 PS5-08-12.