What Is Soft-Tissue Radiation Injury?
Soft-tissue radiation injury refers to pathological changes that develop in muscles, connective tissue, skin and subcutaneous tissue located within the irradiated field.
Unlike acute radiation reactions, which occur during treatment and subsequently subside, chronic soft-tissue injuries develop gradually and tend to worsen over time.
Clinical manifestations vary and may include chronic pain and a sensation of heaviness in the irradiated area, hardening and loss of elasticity in the skin and subcutaneous tissue, reduced range of motion in joints near the radiation field, lymphoedema caused by lymphatic vessel injury, and chronic ulcers that fail to heal.
In patients who have received radiotherapy for breast, head and neck, or pelvic cancer, these complications may significantly affect quality of life after oncological treatment has been completed.
Characteristics of Soft-Tissue Radiation Injury
The principal pathological mechanism is progressive fibrotic degeneration. Radiation activates chronic inflammatory pathways and overstimulates fibroblasts, leading to abnormal collagen deposition. This rigid collagen replaces normal elastic tissue, causing hardening, adhesions and loss of function.
At the same time, radiation-induced vascular injury deprives the tissue of the blood supply required to maintain its normal structure. Irradiated muscle becomes stiff, atrophic and painful. This may be particularly troublesome in areas such as the chest wall following breast radiotherapy or the neck muscles after radiotherapy to the head and neck region.
Scientific Studies
Studies evaluating the effectiveness of hyperbaric oxygen therapy in radiation-induced soft-tissue injury have reported improved vascularisation, reduced fibrotic activity and pain relief in a substantial proportion of patients. Molecular evidence indicates that increased oxygenation inhibits profibrotic factors such as TGF-β1 and activates antioxidant enzymes that limit tissue injury caused by the oxidative stress associated with chronic radiation-induced inflammation.
In patients with radiation-induced lymphoedema and soft-tissue fibrosis in particular, clinical reports have documented improved tissue elasticity, reduced pain and partial restoration of range of motion. These outcomes translate directly into better everyday functions.
Hyperbaric Oxygen Therapy for Soft-Tissue Radiation Injury
In radiation-induced soft-tissue injury, hyperbaric oxygen therapy is used as an adjunctive intervention that addresses the underlying vascular insufficiency and chronic hypoxia, the two principal factors driving fibrotic degeneration and functional impairment.
The reactivation of VEGF-mediated neovascularisation is the most important mechanism. The formation of new capillaries within irradiated tissue restores nutrient and oxygen delivery, gradually allowing the tissue to regain part of its functional integrity. At the same time, the inhibition of profibrotic factors may slow or halt further degeneration.
A typical treatment course consists of 30 to 40 sessions, with progress monitored in collaboration with the oncologist and physical and rehabilitation medicine specialist.