RT Journal Article SR Electronic T1 Standardized Methods Using EUS-guided Fine-needle Biopsy and a Minimal Medium Creates Three Pancreatic Cancer Organoids JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 4103 OP 4109 DO 10.21873/anticanres.15908 VO 42 IS 8 A1 ISHIDA, YUSUKE A1 TSUNODA, TOSHIYUKI A1 HAMADA, YOSHIHIRO A1 TSUCHIYA, NAOAKI A1 KOGA, TAKEHIKO A1 KITAGUCHI, TAKANORI A1 MATSUMOTO, KEISUKE A1 MATSUMOTO, SHINJI A1 SASAKI, TAKAHIDE A1 NAKASHIMA, RYO A1 ISHII, FUMINORI A1 KAJIWARA, MASATOSHI A1 SHIRASAWA, SENJI A1 HASEGAWA, SUGURU A1 HIRAI, FUMIHITO YR 2022 UL http://ar.iiarjournals.org/content/42/8/4103.abstract AB Background/Aim: Recently, endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) has been conducted for diagnosing pancreatic ductal adenocarcinoma (PDAC), after which obtained samples were used in organoid cultures. However, no standardized method for PDAC organoid cultures exists. Therefore, to standardize or simplify sample collection and culture methods for PDAC organoids, we performed a floating culture using non-minced specimens obtained by EUS-FNB in a minimal medium, lacking growth factors or inhibitors for pancreatic organoids. Patients and Methods: A total of 38 patients with clinically diagnosed PDAC were enrolled in the study. First, EUS-FNB was conducted using a 22- or 25-gauge biopsy needle. Then, a surplus of samples was collected for organoid formation after rapid on-site cytological evaluations of sample adequacy. Subsequently, the established organoids were compared with clinical data and pathological diagnosis, following periodic observations and evaluations for morphology. Results: PDAC organoids were successfully created in 24 of the 38 cases (63.2%), including four cases with pathologically inconclusive EUS-FNB results. Afterward, PDAC organoid morphology was classified into ductal, dormant, and adhesive small cluster (ASC) types. Although the ductal and ASC types were seen separately, they were also seen together in other cases, which we named “mixed type”. Conclusion: We propose a feasible and straightforward method for establishing organoids, especially for diagnosing PDAC, particularly when the result of EUS-FNB is pathologically inconclusive. Furthermore, PDAC organoids are morphologically classified into three types reported for the first time.