Application of 4% formaldehyde under electronic colonoscope as a minimally invasive treatment of chronic hemorrhagic radiation proctitis.

To investigate the effectiveness of topical application of 4% formaldehyde as a minimally invasive treatment of rectal bleeding due to chronic radiation proctitis (CRP) under direct vision of electronic colonoscope.The clinical data of 13 CRP patients complicated with ≥ grade II bleeding admitted to our hospital between January 2003 and December 2018 were retrospectively analyzed. Under the guidance of electronic colonoscope, 4% formaldehyde combined with 5-aminosalicylic acid (5-ASA) suppositories was topically applied. Patients were followed up for two months after treatment, and the therapeutic effectiveness was observed and analyzed.The rectal bleeding due to CRP was markedly reduced after topical application of 4% formaldehyde under colonoscope in all 13 patients. The bleeding stopped after one treatment session in 11 patients and after the second session in 2 patients. 5-ASA was also applied along with the use of 4% formaldehyde. The therapeutic effectiveness was satisfactory during the 1- and 2-month follow-up period.Topical application of 4% formaldehyde under the direct vision of colonoscope as a minimally invasive treatment for CRB-induced bleeding is a simple, effective, affordable, and repeatable technique without obvious complications, which deserves further exploration and promotion.