Intrarectal formalin treatment for haemorrhagic radiation induced proctopathy: efficacy and safety

Abstract

Background Pelvic radiotherapy is limited by a dose dependent toxicity to the surrounding organs. Total doses exceeding 60Gy are associated with a higher risk of rectal bleeding. If radiation induced chronic haemorrhagic proctopathy (RHP) is severe and/or causes iron-deficiency anaemia, treatment should be offered. Aim of this prospective study was to evaluate efficacy and safety of intrarectal formalin treatment for haemorrhagic RHP at the Royal Marsden Hospital. Methods Adult patients who received pelvic radiotherapy were enrolled. Haemoglobin was evaluated before the first and after the last formalin treatment. Antiplatelet, anticoagulation treatment and administration of transfusion (indication: RHP) were recorded. Interval between the completion of radiotherapy and the first intrarectal 5% formalin treatment was assessed; dose of radiotherapy was evaluated. Clinical assessment of frequency & amount of rectal bleeding (rectal bleeding score: 1-6) and endoscopic appearance (score: 0-3) were classified. Complications were recorded. Results Nineteen patients were enrolled: 13 males (68%) and 6 females. Mean age was 75±9 years. Median time between completion of radiotherapy and the first formalin treatment was 20 months, inter-quartile range (IQR): 15. Median dose of radiotherapy was 68Gy, IQR: 14. Thirty-two procedures were performed (1.7 per patient). In total, 9/19 (47%) patients were receiving anticoagulation and/or antiplatelet medication. Five patients (5/19, 26%) received transfusion. Mean value of haemoglobin before the first formalin treatment was 110±18g/l, after the last treatment 123±16g/l; p=0.022. Median of rectal bleeding score before the first formalin treatment was 6 (IQR: 0), after the last treatment 2 (IQR: 1-4); p˂0.001. Median of endoscopy score on the day of the first treatment was 3 (IQR: 0); on the day of the last treatment 1 (IQR: 1-2); p˂0.001. The median follow-up was 6 months (IQR: 4-16). One female patient with a persistent rectal ulcer which healed eventually (18 months of healing) developed a recto-vaginal fistula subsequently (complication rate: 1/19: 5%). Conclusions Treatment with intrarectal formalin in RHP is effective and safe.