Peter van Mourik

120 Chapter 5 ABSTRACT Introduction : Intestinal organoids show great potential as in vitro drug testing platform for personalised medicine in cystic fibrosis and oncology. Intestinal organoids can be generated by culturing adult stem cells obtained through forceps biopsy or rectal suction biopsy, but the safety of these procedures and the success rates of generating organoids at a centralized lab using these procedures has not been studied in this context. We here report the safety and success rates of both biopsy procedures and subsequent organoid generation in the international multicentre HIT-CF Organoid Study. Methods : 502 adult patients with Cystic Fibrosis from 33 different hospitals in 12 different countries were included in this study. Based on the preference of the hospital, either forceps biopsies or rectal suction biopsies were obtained and internationally shipped to a central laboratory for organoid generation. Results: No (serious) adverse events were reported for 280 forceps biopsy procedures, while 222 rectal suction biopsy procedures resulted in 2 (serious) adverse events, namely continued bleeding and a probably nonrelated gastroenteritis. The success rate of organoid generation from all biopsies was 95.0%, and the main reason for failure was insufficient sample viability (3.2%). Discussion : Our results indicate that both rectal suction and forceps biopsy procedures are safe procedures, and high success rates of organoid generation from the obtained tissue samples demonstrates the feasibility of the organoid technology for personalised in vitro testing in an international setting.