What is Hyperbaric Treatment of Delayed Radiation Injury?
This year, about 1.2 million people in the United States will be diagnosed with a severe type of cancer. Half of these patients will undergo radiation therapy as part of their treatment plan. Unforunately, around 5% of these patients, or approximately 30,000 cases per year, may experience serious complications due to the radiation therapy.
Radiation is measured in units called Rads and Grays. So, when you hear your doctor talk about these, they’re essentially talking about the amount of energy given off by the radiation. To put it simply, 1 rad, also known as 1 centigray (cGy), is the equivalent of 100 ergs of energy for each gram of body tissue.
Something else to know is that sometimes, the effects of radiation don’t show up right away. These delayed effects are often only discovered when the body receives another form of damage, such as during a surgical procedure or after a physical injury.
What Causes Hyperbaric Treatment of Delayed Radiation Injury?
Radiation can cause damage to our body’s cells in several ways, including harming our DNA, causing harmful reactions in fats (lipid peroxidation), and changing the shape of proteins (protein denaturation). This can sometimes lead to cell death or the cell not working correctly. In many cases, over time, radiation can cause a certain type of inflammation and narrowing in the small blood vessels.
Current research shows that the process of harm caused by radiation actually starts during the time of radiation therapy. This involves releasing many active biological substances, especially fibrogenic cytokines, which are proteins that can cause fibrosis, a type of tissue scarring. TGF-beta is one particular cytokine that researchers have studied extensively in relation to the delayed effects of radiation.
Acute/Subacute side effects from radiation usually start after a dose of 5000 centigray (cGy), a unit used to measure radiation. Acute injuries happen almost immediately due to free radical damage to our cells’ DNA.
Subacute injuries, which usually affect the lungs, happen 2 to 3 months after radiation.
Delayed injuries can take more than 6 months to several years after completing radiation treatment to show up. These usually occur after further injuries in the previously radiated field due to activities such as surgery or trauma. Delayed radiation injuries often develop after a total dose of 6500 centigray (cGy).
Risk Factors and Frequency for Hyperbaric Treatment of Delayed Radiation Injury
Hyperbaric oxygen therapy is a treatment used by around a third of patients in the United States to manage the late effects of radiation therapy. Over the past 50 years, there have been significant advances in cancer treatment and prognosis. There are now many types of cancer that no longer always result in death and can often be survived. However, the radiation used in cancer treatment has both positive and negative effects. While it’s great at destroying cancer cells, it can also unavoidably harm healthy tissue.
Even though a patient may be cured of cancer, they may still suffer from delayed radiation injury. This might not be apparent until many months or even years after the radiation treatment has ended. Additionally, these delayed radiation injuries can often be brought on following an incident such as an accident or surgery.
Signs and Symptoms of Hyperbaric Treatment of Delayed Radiation Injury
People who experience delayed side effects from radiation therapy often have conditions like radiation cystitis, radiation proctitis, vaginal radionecrosis, soft-tissue radionecrosis, and laryngeal radionecrosis.
Patients treated with radiation to the head and neck for cancers in the soft tissue and palate or bone may suffer from a condition called osteoradionecrosis of the jaw. Signs of this condition include exposed bone in the jaw that does not heal even after six months of treatment, and chronic draining sinus tracts and fistulas from the bone.
It’s crucial to note when radiation treatment ended and how much of a radiation dose was given. Doses higher than 6500 cGy can lead to osteoradionecrosis and soft-tissue radionecrosis. It’s also important to note whether the patient had recent bone biopsies, the salvage surgery, any physical harm due to oral or dental devices, dental or gum diseases, or extractions.
Another common side effect is seen in women who have undergone radiation for breast cancer. This radiation can cause the chest-wall tissue to thicken and lose its blood supply, making it difficult or even impossible for successful reconstruction and healing to occur after surgery.
Testing for Hyperbaric Treatment of Delayed Radiation Injury
If you’re going for a hyperbaric oxygen treatment to help with any lingering or delayed effects of radiation, there are some steps you’ll have to take. A formal chat with the doctor who specializes in hyperbaric treatment and the rest of the care team is first on the list. The purpose of this meeting is to ensure they have all the information needed to diagnose your current health status and to figure out the best treatment plan for you.
To help your hyperbaric doctor come up with the right treatment plan, they will need:
- Your radiation therapy history, especially the total amount of radiation you’ve had and the dates of your treatment.
- If you’ve had chemotherapy, the details about this. This includes what medicines were used.
- Your most recent imaging test results, like PET, CT, or MRI scans. This is to prove that you don’t currently have cancer.
- Paperwork and reports from the doctor who told you to see a hyperbaric medicine specialist.
All of the above would help the team develop the best action plan for your treatment.
Treatment Options for Hyperbaric Treatment of Delayed Radiation Injury
The treatment for damaged tissues varies based on the specific tissue that is affected. Dr. Robert Marx has conducted significant research on the use of hyperbaric oxygen therapy for a condition known as osteoradionecrosis of the jaw. This condition, often occurring in patients who have undergone head and neck radiation, is characterized by the death of bone tissue due to lack of blood supply.
His research showed that for this hyperbaric oxygen therapy to be effective, it needs to be used along with surgery and antibiotic treatment. Dr. Marx underscored the importance of using hyperbaric oxygen therapy before surgery to increase the healing response of the body.
Aside from treating osteoradionecrosis, hyperbaric oxygen therapy has also been used successfully to treat laryngeal necrosis and other conditions caused by deterioration of soft tissue in the head and neck. These changes often arise as late effects of radiation therapy. The hyperbaric oxygen therapy can enhance the health of the tissue before and after surgery and boost the survival rate of surgical flaps in areas of the head and neck that have previously undergone radiation.
There is increasing evidence that suggests hyperbaric oxygen therapy can help prevent complications from radiation therapy. Its application is typically seen when a surgery is planned in an area that has previously received radiation treatment and there’s a high risk of complications and wound healing difficulties.
Given this information, what seems to be a reasonable approach is to utilize hyperbaric oxygen therapy as an additional or “adjunctive” treatment when surgery is planned in an area that has experienced significant radiation exposure.
What else can Hyperbaric Treatment of Delayed Radiation Injury be?
These are some health conditions that you should be aware of:
- Bowen’s disease
- Burns
- Basal carcinoma (a type of skin cancer)
- Cold injuries
- Early diabetes
- Marjolin’s ulcer (a specific type of aggressive skin cancer)
- Obesity
- Polyarteritis nodosa (a rare disease in which small and medium-sized arteries become swollen and damaged)
- Systemic lupus erythematosus (a chronic autoimmune disease that can affect any part of the body)
- Venous stasis (poor blood flow in the veins, usually in the legs)