Radiation therapy is a common cancer treatment that uses high-energy radiation to shrink tumors and destroy cancer cells. This treatment works by damaging the DNA within cancer cells, preventing them from growing and dividing. While the primary goal of radiation is to target cancerous tissue, it can also affect healthy cells in the surrounding areas.
How Radiation Therapy Affects Immunity
Radiation therapy can weaken the immune system by affecting rapidly dividing cells, particularly those in the bone marrow. The bone marrow produces white blood cells (leukocytes), essential for the immune system. Damage to bone marrow stem cells reduces the body’s ability to produce enough infection-fighting cells.
Lymphocytes, a type of white blood cell highly sensitive to radiation, are often significantly impacted. Even low doses can lead to their depletion. This reduction, known as lymphopenia, can persist for months after treatment and is linked to an increased risk of infection. The extent of immune system impact depends on the total radiation dose, the specific area treated, and treatment duration. Radiation targeting large bone marrow areas carries a higher risk of immune suppression.
Recognizing Signs of Weakened Immunity
Patients undergoing radiation therapy should be aware of signs of a weakened immune system. A compromised immune system increases susceptibility to infections, which can manifest as fever, chills, and general feelings of illness. Other common indicators include increased fatigue and skin changes in the treated area, such as redness, dryness, or peeling.
Monitor these symptoms, as infections can become serious quickly when white blood cell counts are low. Any new or worsening symptoms, particularly fever (100.4°F or 38°C or higher), should be reported to the healthcare team immediately. Prompt communication allows for timely intervention and management of complications.
Protecting Your Immune System During Treatment
During radiation therapy, taking steps can help protect a weakened immune system. Practice frequent handwashing or use an alcohol-based hand sanitizer. Avoid close contact with sick individuals to reduce infection risk.
Food safety is also important. Patients may be advised to avoid foods with a higher risk of bacterial contamination, such as unpasteurized dairy, raw eggs, and undercooked meats. Irradiated foods, treated to destroy microorganisms, can be a safer option for those with impaired immune systems. Discuss vaccination schedules with the care team; live vaccines are generally not recommended during treatment, while inactivated vaccines may be safe and beneficial.
Immune System Recovery After Radiation
The immune system typically begins to recover after radiation therapy concludes, though full recovery time varies. For many patients, bone marrow effects are minimal, and counts may return to normal within weeks. For those with more significant immune system impact, recovery might take several months.
Factors such as treatment type and duration, total radiation dose, and individual health influence the recovery period. Healthcare providers will monitor immune cell counts and manage lingering effects. Maintaining a healthy lifestyle, including balanced nutrition and adequate rest, supports the body’s recovery process.