Hyperbaric oxygenation for tumour sensitisation to radiotherapy

Area of Science:

• Oncology
• Radiotherapy
• Hyperbaric Medicine

Background:

• Radiotherapy is a standard treatment for several solid tumors.
• Hypoxic cancer cells are less responsive to radiotherapy.
• Hyperbaric oxygenation therapy (HBOT) may enhance radiotherapy's efficacy against hypoxic tumors.

Purpose of the Study:

• To evaluate the benefits and harms of administering radiotherapy while patients breathe hyperbaric oxygen (HBO).

Main Methods:

• Systematic review and meta-analysis of randomized and quasi-randomized controlled trials.
• Searched multiple databases including CENTRAL, MEDLINE, and EMBASE up to March 2011.
• Included 19 trials with 2286 patients comparing radiotherapy with HBO versus air.

Main Results:

• HBOT showed a reduction in mortality for head and neck cancers at 1 and 5 years (NNT 11 and 5).
• Improved local tumor control at 3 months (NNT 7) and reduced local recurrence at 1-5 years for head and neck and uterine cervix cancers (NNT 5-6).
• Significant increase in severe radiation tissue injury (NNH 8) and seizures during therapy (NNH 22) with HBOT.

Conclusions:

• HBOT demonstrates potential benefits for head and neck and uterine cervix cancer control and mortality, particularly with specific fractionation schemes.
• Significant adverse effects, including severe tissue injury and seizures, are associated with HBOT.
• Methodological limitations necessitate cautious interpretation; further research is needed for head and neck cancers, but not recommended for bladder cancer.