Genotoxicity, Hyperbaric Oxygen, Malignancy
Conditions
Brief summary
Hyperbaric Oxygen Therapy (HBOT) is a treatment involving the administration of oxygen at pressures higher than atmospheric pressure, with numerous potential indications such as radiation-induced tissue damage, chronic wounds, and more. HBOT significantly increases the amount of dissolved oxygen in tissues, thereby promoting wound healing. However, this "hyperoxygenation" may also exert toxic effects, particularly through the production of reactive oxygen species (ROS), which can induce DNA damage and potentially promote mutagenesis, thereby increasing long-term neoplastic risk. A single HBOT session is associated with a significant increase in ROS production, which may persist for up to 48 hours post-exposure, and is also linked to DNA damage. DNA repair is typically a rapid process, with the activation of protective mechanisms. The effects of repeated HBOT sessions remain a matter of debate. Reported outcomes range from attenuation of genotoxicity, to exacerbation of DNA damage, or no effect at all (8). In patients with cancer or comorbidities associated with impaired DNA repair capacity, repeated HBOT could be more detrimental, potentially increasing genotoxic effects and cancer risk. This increased oxygen susceptibility in cancer patients has already been observed in normobaric conditions during abdominal surgery, where hyperoxygenation strategies were associated with increased mortality in this subgroup. A potential pro-carcinogenic effect of HBOT in cancer patients has also been suggested in some case series, though not confirmed by larger studies. Current literature on HBOT safety remains generally reassuring; however, the possibility of DNA damage and its potential long-term genotoxic consequences cannot be entirely excluded. This question is of particular importance given that many primary indications for HBOT involve patients with a history of malignancy or active cancer
Interventions
BIOLOGICALBlood test
a blood test before and after the first oxygen therapy session, as well as after the last session
Sponsors
University Hospital, Angers
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adults (≥18 years old) * Having signed an informed consent form * Affiliated with or beneficiary of a national health insurance system * Admitted to the hyperbaric medicine department for HBOT treatment * Either for a complication related to prior radiotherapy (administered for an underlying neoplastic disease), such as: Radiation cystitis Radiation proctitis / enteritis Radiation dermatitis Mandibular osteoradionecrosis Or for another indication, without any underlying neoplastic disease
Exclusion criteria
* Patients with a contraindication to hyperbaric oxygen therapy (HBOT) * Pregnant, breastfeeding, or postpartum women * Patients deprived of liberty by judicial or administrative decision * Patients undergoing involuntary psychiatric treatment * Patients under legal guardianship or protective custody
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlation between hyperbaric oxygen therapy and DNA damages | Baseline (inclusion, before the first oxygen therapy session), during treatment(just after the first oxygen therapy session) and immediately after treatment (just after the last oxygen therapy session) | Tail DNA Percentage by the Comet Assay (cellular biology technique, single-cell gel electrophoresis) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| reactive oxygen derivatives formation | Baseline (inclusion, before the first oxygen therapy session), during treatment(just after the first oxygen therapy session) and immediately after treatment (just after the last oxygen therapy session) | 8-hydroxy-2'-deoxyguanosine (8-OHdG) plasma levels |
| Correlation between DNA damage and post-radic wound healing | Baseline (inclusion, before the first oxygen therapy session), during treatment(just after the first oxygen therapy session) and immediately after treatment (just after the last oxygen therapy session) | Grade difference on the LENT-SOMA scale (Late Effects of Normal Tissues-Subjective, Objective, Management, Analytic) |
Countries
France
Contacts
CONTACTMarie Lemerle, Doctor
Outcome results
None listed