Hyperbaric oxygen therapy (HBOT) in the pelvic region, a study shows, can relieve self-reported symptoms and side effects of radiotherapy against cancer. Most patients reported reductions in vomiting, urinary incontinence and discomfort following 30–40 sessions in a hyperbaric chamber.

“This treatment is highly effective for the majority of the patients” states Nicklas Oscarsson, first author of the article, a doctoral student in anesthesiology and intensive care at Sahlgrenska Academy, University of Gothenburg, and senior consultant at Angered Hospital.

Radiation therapy is part of many cancer treatment procedures for organs like the heart, cervix, ovaries, and colon. In the lower abdomen, one side effect of radiotherapy is damage to nearby healthy tissue such as the urinary tract, bladder, vagina, or rectum.

Symptoms such as frequent urination, incontinence, vomiting, and severe abdominal pain cause physical as well as social problems. These can occur several years after radiation therapy and cause chronic pain that often increases. Temporary relief of symptoms or mutilating surgery can often be offered to all of these patients.

Oxygen and high pressure

In the current study, 223 patients were screened in The Lancet Oncology, the first randomized controlled trial to equate hyperbaric oxygen with standard care, and 79 were included in the review. Patients reported relatively severe symptoms and limitations of lifestyle, mainly due to reduced capacity of the urinary bladder, bleeding, incontinence and pain.

At university hospitals in five northern cities, the patients are treated: Bergen in Norway, Göteborg and Stockholm in Sweden, Copenhagen in Denmark and Turku in Finland. The control group of 38 patients received standard treatment that normally includes medicine and physical therapy, while the remaining 41 patients underwent hyperbaric oxygen treatment for 90 minutes a day, 30–40 days.

Each of the latter patients sat in a hyperbaric chamber for one or more people during their sessions, wearing a snug-fitting oxygen mask or hood. The oxygen pressure, 240 kilopascals (kPa), at a depth of 14 meters corresponded to the water pressure.

Focus on quality of life

Two out of three patients felt better in the hyperbaric chamber group, and in some cases all of the symptoms disappeared. No major changes were made by the others, including the control group. The study's specific focus is on self-reported qualitative and quantitative symptoms as well as the important issue of cancer survivors ' quality of life.

The thesis is also related to the results behind the 2019 Nobel Prize in Physiology or Medicine on how cells are detecting and responding to the availability of oxygen. Hyperbaric oxygen therapy has already been known to boost vascular growth, but little exploration of its specific effects has been done.

General health was severely impaired in the patients in the study prior to treatment, sometimes after long periods of pain. Therefore, if a person was no longer in need of medication for pain and could go to the bathroom once a night instead of five days, it was a clear improvement.

“It’s a great pleasure to hear patients tell us how they feel they’re returning to a normal human life. This also applies to those who get better but perhaps aren’t entirely well,” Oscarsson concludes.