3261 - Rising Utilization of Hyperbaric Oxygen Therapy for Radiation-Related Genitourinary Injury: A 10-Year Institutional Analysis

Purpose/Objective(s):

Hyperbaric oxygen therapy (HBOT) is an established treatment for radiation-induced injury, yet contemporary utilization patterns remain poorly characterized. With increasing adoption of stereotactic body radiation therapy (SBRT) for genitourinary (GU) malignancies and emerging prospective evidence supporting HBOT for radiation cystitis, including the randomized RICH-ART trial, we hypothesized that HBOT use for radiation-related GU injury has increased over time. We performed a 10-year institutional analysis to evaluate trends in HBOT indications, treatment intensity, and insurance coverage.

Materials/Methods:

We conducted a retrospective study of all patients treated with HBOT at a single institution using a prospectively maintained departmental registry from 2015–2025. Indications were defined using ICD-9/10 codes. All analyses were performed in R.

Results:

Among 1,137 HBOT patients (31,393 treatments), 43.6% were treated for radiation-related indications (RRI) and 56.4% for other diagnoses. RRI comprised 42–59% of annual volume through 2023, declining to 38–39% in 2024–25 despite rising overall volumes. RRI received more treatments per course (median 36 vs. 19; p<0.001) and were more likely to require retreatment (19.2% vs. 9.8%; p<0.001), with similar inter-course intervals (60–77 days).

Within RRI, GU injury (cystitis/bladder injury) was most common (36.1%), followed by soft tissue injury (22.0%) and osteoradionecrosis (16.5%). Non-RRI were most frequently graft complications and hearing loss (each 25%), followed by diabetes-related complications (14.7%).

Insurance coverage among RRI was balanced overall (private 51.9%, public 49.5%), shifting from public predominance (60–70%) in 2015–17 to private predominance (55–60%) thereafter. Non-RRI were predominantly privately insured (75.2%), with private coverage rising to 68–89% annually since 2018.

Radiation GU injury increased from 11.3% of RRI in 2015 to >50% annually by 2023–25. Osteoradionecrosis declined after 2017 (38.9%) to 5–8% in recent years, while soft tissue injury remained stable. Trends assessed using binomial logistic regression differed significantly (p<0.001): GU increased annually (OR 1.26), osteoradionecrosis decreased (OR 0.83), and soft tissue injury showed no significant change.

Conclusion:

HBOT use for radiation-related GU injury has increased and is now the dominant RRI, while osteoradionecrosis has declined. Overall growth has also been driven by non-radiation indications. Private insurance coverage has expanded, surpassing public payors for radiation-related cases. It remains unclear whether rising HBOT use for GU injury reflects strengthening evidence and improved coverage or increased late GU toxicity in the modern SBRT era. Multi-institutional studies are needed to clarify drivers of utilization and inform evidence-based referral and coverage practices.