What Researchers Did
Researchers systematically reviewed 42 studies (2,785 patients) published between 2000 and 2025 on HBOT for managing side effects from radiation therapy in cancer patients.
What They Found
HBOT showed high response rates of 67–100% for hemorrhagic cystitis (bladder bleeding) from pelvic radiation. For breast and head-and-neck cancers, HBOT improved quality of life in retrospective reports but randomized trials did not show consistent benefit. The median treatment was 34.5 sessions at 2.45 atmospheres. HBOT was generally safe, with minor side effects including ear barotrauma and temporary vision changes.
What This Means for Canadian Patients
For Canadians who develop bleeding from the bladder or rectum after pelvic radiation for prostate, cervical, or rectal cancer, HBOT has the strongest evidence base among radiation side effects — with response rates up to 100% in some studies. Patients in Ontario with radiation cystitis or proctitis should ask their oncologist about HBOT as a covered treatment option.
Canadian Relevance
Delayed radiation injury — including radiation cystitis and radiation proctitis — is an OHIP-covered indication for HBOT in Ontario.
Study Limitations
Most included studies were retrospective and small; only 5 of 42 were randomized controlled trials, making it difficult to draw definitive conclusions about HBOT's effectiveness across all cancer sites.