The Comparison of Acute Clinical Outcome between 30 and 40 Sessions of Hyperbaric Oxygen Therapy for Management of Visible Hematuria from Radiation-Induced Hemorrhagic Cystitis

Background: Radiotherapy is one of the most popular treatments for pelvic malignancy, which causes patients suffering from the adverse effect such as cystitis, hematuria, proctitis, hematochezia and distal ureteric stricture. The hematuria condition from radiation-induced hemorrhagic cystitis is the most common adverse event suffering the patients, losing properties, wasting time, and deteriorating quality of life. One of the most effective treatments for radiation-induced hemorrhagic cystitis is the hyperbaric oxygen therapy with no necessity for patients to be hospitalized, no need of anesthesia use, and also non-invasion. However, it requires that patients spend 90 - 120 minutes a day for 40 days administered out-patient treatment session. The transportation cost as well as the accommodation one will greatly burden the self-pay health care patients. In addition, there is still no definite standardized number of HBOT treatment session assignment at present. Objectives: To compare the treatment outcome (bladder mucosal characteristics, red blood cells in urine) between 30 and 40 sessions of HBOT for treatment of radiation-induced hemorrhagic cystitis. Methods: Prospective cohort observational study of patients (n = 15) who were diagnosed with radiation-induced hemorrhagic cystitis that were treated with hyperbaric oxygen therapy in Somdechprapinklao Hospital between October 2020 and September 2021. We compared the parameter about hemoglobin concentration, red blood cell number in urine during the course of HBOT treatment every 10 sessions and cystoscopic finding severity as EORTC/RTOG classification for radiation-induced hemorrhagic cystitis in Table 1 before treatment, and after 30 and 40 sessions of treatment. Results: From 15 of treated patients, 93.3% of patients had evidence of posterior wall lesion. The mean duration from radiotherapy (radiation and brachytherapy) to the first episode gross hematuria is 112 months. This study shows no statistically different cystoscopic findings as EORTC/RTOG classification for radiation-induced hemorrhagic cystitis after 30 and 40 sessions of HBOT (p = 0.653) and statistically significant improvement after the treatment of more than 30 sessions (p = 0.008). No relationship was found with the hemoglobin concentration and red blood cell number in urine during the course of HBOT. Conclusions: Radiation-induced hemorrhagic cystitis can be treated with HBOT. There is no different treatment outcome between 30