Primary cystic duct carcinoma is a rare tumor. The curative treatment of cystic duct carcinoma is complete surgical resection, for which the evaluation of local extension is important. We herein report two cases of cystic duct carcinoma in which a preoperative examination was performed using per-oral cholangioscopy (POCS). Both patients underwent POCS due to suspicion of cystic duct carcinoma based on imaging findings. A visual analysis and biopsy were performed to evaluate local extension, which led to surgery. These cases suggest that POCS is useful for the preoperative assessment of local extension in advanced cystic duct carcinoma.

Background and Aim The use of proton pump inhibitors (PPIs) has been repeatedly reported as a trigger of Clostridioides difficile infection (CDI), a leading cause of nosocomial diarrhea. However, only a few studies have reported on the association between vonoprazan, a novel potassium‐competitive acid blocker providing potent acid suppression, and CDI, with no studies having been conducted in a clinical setting. We therefore evaluated the association between various classes of acid suppressants and CDI with special attention paid to differences in the magnitudes of association between PPIs and vonoprazan. Methods A retrospective hospital‐based cohort from a secondary‐care hospital in Japan (n = 25 821) was collected, wherein eligible CDI cases were defined as hospital‐onset cases (n = 91). A multivariable adjusted logistic regression analysis for the entire cohort and propensity analyses for subgroups consisting of PPI and/or vonoprazan users at various doses (n = 10 306) were performed. Results The overall CDI incidence rate was 1.42/10 000 patient‐days, which was comparable with previous reports. A multivariable analysis showed that both PPIs and vonoprazan were positively associated with CDI (odds ratios [95% confidence intervals]: 3.15 [1.67–5.96] and 2.63 [1.01–6.88], respectively). In addition, matched subgroup analyses showed that PPIs and vonoprazan had equivalent magnitudes of association with CDI. Conclusions We found that both PPIs and vonoprazan were associated with CDI, and the magnitude of the association was comparable. Because vonoprazan is widely available in Asian countries, further studies on the association of its usage with CDI are warranted.

We herein report a case of recurrence of epithelial ovarian carcinoma 41 years after the primary surgery that was diagnosed by an endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). The differential diagnosis based on the imaging findings was difficult. We performed an EUS-FNB and compared the EUS-FNB specimen to the surgical specimen that had been resected in the primary surgery for ovarian carcinoma 41 years earlier, including immunohistochemical staining. Finally, we made a definitive diagnosis of extremely late recurrence of ovarian carcinoma of the retroperitoneum. An EUS-FNB enables an accurate histological diagnosis by obtaining a sample that is large enough to perform immunohistochemical staining.

Splenic sarcoidosis is often diagnosed by splenectomy or an ultrasound-guided splenic biopsy. However, splenectomy is invasive and costly, and a percutaneous biopsy is sometimes difficult. We herein report a case of splenic sarcoidosis diagnosed with endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). A 71-year-old man was referred to our hospital for abnormal shadows on a chest roentgenogram. Computed tomography showed multiple lesions in the spleen and pulmonary consolidations. Bronchoscopy revealed no definitive diagnosis. We therefore performed EUS-FNA for a splenic lesion that led to the diagnosis. This case suggests that EUS-FNA is useful in confirming the diagnosis of sarcoidosis with suspected splenic lesions.