Endorectal formalin instillation or argon plasma coagulation for hemorrhagic radiation proctopathy therapy: a prospective and randomized clinical trial.

BACKGROUND AND AIMS: Radiotherapy may cause hemorrhagic radiation proctopathy (HRP). For conservative treatment of refractory HRP, argon plasma coagulation (APC) is the first-choice therapy. Endorectal formalin instillation (EFI), in turn, is an attractive treatment option because of its satisfactory results, great availability, and low cost. Nevertheless, comparative studies between these procedures are rather scarce. This study aims to make a prospective and randomized comparison of the outcomes in 2 HRP patient groups treated with either APC or EFI.

METHODS: Twenty-seven patients (11 women), with a mean age of 67 years (range, 36-83), were randomized to receive either APC (n = 14) or EFI (n = 13). On completion of the treatment, comparisons were made in relation to the baseline for each patient and between groups for endoscopic findings according to the Vienna score and the telangiectasia distribution pattern score (TDP); the impact of radiation proctitis on patients' lives was made according to the modified radiation toxicity score (MRTS) and hemoglobin levels. Number of sessions, duration of therapy, and adverse events were also compared between groups. The endoscopic therapeutic success (ETS) was defined by the absence or only few residual telangiectasias (TDP ≤1) on conclusion.

RESULTS: An ETS of 92.8% was achieved in patients treated with APC and 92.3% for those treated with EFI (P > .05); there was an MRTS improvement of 85.7% in APC patients and 69.2% in EFI patients (P > .05). Mild adverse events occurred, respectively, in 23% and 28.5% in the EFI and APC groups (P > .05).

CONCLUSIONS: The study showed that APC and EFI have similar efficacy and a high safety profile for HRP treatment. (Clinical trial registration number: 3.120.353.).