Efficient Establishment of Bile-Derived Organoids From Biliary Cancer Patients.

Patient-derived tumor organoids have considerable potential as an in vitro diagnostic tool for drug susceptibility testing. In the present study, we investigated whether bile collected for diagnostic purposes could be a potential source for the establishment of biliary cancer organoids. Among 68 cases of biliary cancer, we successfully generated 60 bile-derived organoids (BDOs) from individual patients. Consistent with previous reports that described biliary cancer organoids from surgical tissues, the BDOs showed diverse morphologies such as simple cysts, multiloculated cysts, thick capsulated cysts, and solid masses. They also harbored mutations in KRAS and TP53 at frequencies of 15% and 55%, respectively. To enrich the cancer organoids by removing contaminated noncancerous components of BDOs, we attempted to verify the effectiveness of 3 different procedures, including repeat passage, xenografting, and selection with an MDM2 inhibitor for TP53 mutation-harboring BDOs. By monitoring the sequence and expression of mutated TP53, we found that all these procedures successfully enriched the cancer organoids. Our data suggest that BDOs can be established with minimal invasiveness from almost all patients with biliary cancers, including inoperable cases. Thus, despite some limitations with respect to the characterization of BDOs and methods for the enrichment of cancer cell-derived organoids, our data suggest that BDOs could have potential applications in personalized medicine.

Rectal varix treated with endoscopic cyanoacrylate injection therapy.

There is no established treatment for rectal varices. Although endoscopic cyanoacrylate (N-butyl 2-cyanoacrylate) injection therapy is the standard treatment for gastric varices, there are few reports of its use for rectal varices. We present a case of rectal varix that was successfully treated with endoscopic cyanoacrylate injection therapy. An 80-year-old man with cirrhosis was treated for rectal varices with interventional radiology 2 years earlier. At his current presentation, he underwent colonoscopy for hematochezia and anemia, which showed recurrence of rectal varix. We performed endoscopic cyanoacrylate injection therapy for the lesion. However, since we observed bleeding from the treated varix the next day, additional cyanoacrylate was injected. Thereafter, there was no re-bleeding and no recurrence was observed at the 3-year follow-up. According to the previous reports, interventional radiology (IVR), endoscopic sclerotherapy (EIS), and endoscopic variceal ligation (EVL) have been mainly used to treat rectal varices; however, there are few reports of endoscopic cyanoacrylate injection therapy. Our case suggests that endoscopic cyanoacrylate injection therapy might be a useful and safe treatment option for rectal varices.