Effect of Premedication With Pronase Before Upper Gastrointestinal Endoscopy

<bold>Objectives: </bold>This study aimed to confirm whether premedication with pronase before endoscopy improves mucosal visualization and increases precancerous lesion and cancer lesion detection rates. <bold>Materials and methods: </bold>From June 2018 to April 2019, out-patients scheduled for endoscopy from 13 hospitals were screened to be randomly allocated in a 2:1 ratio to premedication with pronase (group A) and water (group B). The primary endpoint was mucosal visibility scores, and the secondary endpoint was precancerous and cancer lesion detection rates. This trial was registered at Chinese Clinical Trial Registry, and the registration number was ChiCTR1800016853. <bold>Results: </bold>Group A showed significantly lower mucosal visibility scores (better mucosal visibility) of esophagus, stomach, and duodenum than group B, with all P -values <0.001. The overall cancer detection rates between group A and group B were 0.83 and 1.08%, and overall detection rates of precancerous and cancer lesion were 4.4 and 4.9%, both without significant difference ( P =1.000 and 0.824). In addition, the flushing volume (milliliter) of group A (10.52 +/- 23.41) was less than group B (36.30 +/- 52.11) ( P <0.001), and the flushing frequency of group A (0.46 +/- 1.01) was fewer than group B (1.62 +/- 2.12) ( P <0.001). <bold>Conclusions: </bold>Premedication with pronase could achieve better mucosal visibility and decrease flushing frequency and volume, but may not increase lesion detection rates.