Time to subsequent therapy (TTST) as an endpoint in clinical studies: development of standardized documentation of subsequent therapy through systematic literature review, expert interviews, and Delphi survey - Bianca Biedenweg; Thorsten Ruppert; Thomas Kohlmann; Martin Danner; Anja Mehnert-Theuerkauf; Diana Lüftner; Ulrike Filippig; Janine Ziemann; Ulrike Osowski; Peter Kaskel (Journal of Cancer Research and Clinical Oncology, 2026)