Endoscopic flushing with pronase improves the quantity and quality of gastric biopsy: A prospective study

Background and study aims: Pronase, a proteolytic enzyme, is known to improve mucosal visibility during esophagogastroduodenoscopy (EGD), but little is known about its effects on gastric biopsy. This study assessed whether endoscopic flushing with pronase improves the quality of gastric biopsy. Patients and methods: Consecutive patients who underwent EGD were randomly assigned to either the control group or the pronase group in a prospective setting. The first biopsy of the identified lesion was performed during endoscopy. Endoscopic flushing with either 50mL of water and dimethylpolysiloxane (DMPS; control group) or 50mL of water, pronase, sodium bicarbonate, and DMPS (pronase group) was then applied to the lesion. After 5 minutes, the second biopsy was performed 2-3mm away from the first biopsy site. The thickness of mucus, depth of the specimen, overall diagnostic adequacy, anatomical orientation, and crush artifact were measured to assess the quality of the biopsy. Results: Of the 208 patients, 10 were not analyzed due to the absence of an identifiable lesion. Compared with the control group, the pronase group showed significantly decreased thickness of mucus (P<0.001), increased depth of biopsy (P<0.001), improved anatomical orientation (P=0.010), and improved overall diagnostic assessment (P=0.011) in the second biopsied specimen following endoscopic flushing. The crush artifact and hemorrhage did not differ between the groups. Conclusions: Endoscopic flushing with pronase not only improved the depth of biopsy but also the anatomical orientation and overall diagnostic adequacy. Pronase can be recommended for flushing during EGD to improve the quantity and quality of biopsy.