Abstract 5438: Establishment of an academic tissue microarray platform as an efficient tool for soft tissue sarcoma research
Authors: Lee Che-Jui , Wozniak Agnieszka , van Cann Thomas , Wellens Jasmien , Zlobec Inti , Christian Britschgi , Bovée Judith V.M.G , Sciot Raf , Schöffski Patrick 
Published: September 2020

Abstract
Objective: Soft tissue sarcoma (STS) is a rare and heterogeneous family of mesenchymal tumors, characterized by morphological and genetic diversity. Histopathology and molecular profiling is used in both clinical routine and in sarcoma research, then primarily relying on the availability of archival material. Tissue microarrays (TMAs) from sarcoma tissue blocks have potential advantages over conventional tissue analysis from individual patients in terms of efficiency and cost-effectiveness. Since 2015 we have built TMAs in the Laboratory of Experimental Oncology at KU Leuven (Leuven, Belgium), using left-over archival material available from STS patients.
Methods: For the TMA construction, donor blocks were selected according to the following criteria: blocks with sufficient tumor tissue and height at least 3 mm from STS patients diagnosed at the University Hospitals Leuven, Leuven, Belgium; Leiden University Medical Center, Leiden, The Netherlands and University Hospital Zürich, Zürich, Switzerland, as well as STS patients enrolled in EORTC phase 2 trial 90101 “CREATE”. Cases included in the TMAs are well annotated in terms of pathological diagnosis, treatment and clinical follow-up. Each TMA block contains duplicate or triplicate 1.0-1.5 mm tissue cores from representative areas selected by reference sarcoma pathologists. The construction of TMAs was performed with TMA Grand Master (3DHistech) at the Translational Research Unit at University of Bern, Switzerland or in Leiden, The Netherlands.
Result: At present we have created TMAs from the following STS subtypes: clear cell sarcoma (CCSA, 22 and 32 cases per TMA block), alveolar soft part sarcoma (ASPS, 12 and 47), inflammatory myofibroblastic tumor (IMFT, 12 and 21), alveolar rhabdomyosarcoma (24) and leiomyosarcoma (55). For CCSA, ASPS and IMFT we have separate TMAs from local clinical cases and from EORTC 90101 “CREATE”. For drug- and target-screening purposes in a broader range of STS we also made TMAs representing multiple, most common subtypes: angiosarcoma, dedifferentiated, pleomorphic and myxoid liposarcoma, leiomyosarcoma, malignant peripheral nerve sheath tumor, myxofibrosarcoma, rhabdomyosarcoma, synovial sarcoma and undifferentiated pleomorphic sarcoma, with 7-11 individual cases per tumor type. TMA construction is still ongoing in other relevant sarcoma subtypes.
Conclusion: We have built and are currently expanding a ready to use TMA platform representing the broad heterogeneity of STS. TMAs are available for rapid and cost-effective morphological, immunohistochemical and molecular characterization and identification of novel diagnostic markers as well as drug targets. The platform is readily available to academic partners for collaboration.
Citation Format: Che-Jui Lee, Agnieszka Wozniak, Thomas van Cann, Jasmien Wellens, Inti Zlobec, Britschgi Christian, Judith V.M.G Bovée, Raf Sciot, Patrick Schöffski. Establishment of an academic tissue microarray platform as an efficient tool for soft tissue sarcoma research [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5438.