Radiation Therapy (Radiotherapy)

Radiation therapy uses high-energy beams (such as X-rays, protons, or other particles) to damage the DNA of cancer cells, preventing them from growing and dividing. It is one of the most common cancer treatments, used alone or in combination with surgery, chemotherapy, or immunotherapy. Radiation may be applied with curative intent, to shrink tumors before surgery, to prevent recurrence after surgery, or to relieve symptoms (palliative care).

• A detailed treatment planning session (simulation) is performed first. This may involve CT or MRI scans to map the tumor precisely.
• Skin in the treatment area should be clean and free of lotions, perfumes, or powders.
• Small skin marks or temporary tattoos may be placed to guide beam alignment.
• Discuss current medications, previous treatments, and general health with your oncology team.

Most patients receive external beam radiation therapy. You will lie on a treatment table while a linear accelerator delivers focused radiation beams. Immobilization devices may be used to keep your body still. Each session is painless and usually lasts 10-30 minutes, though setup takes additional time.

Treatment is typically given 5 days a week for several weeks, depending on the cancer type and treatment goals. Other forms include brachytherapy (internal radiation) and systemic radiation therapy, depending on diagnosis.

• Short-term effects: fatigue, skin irritation (similar to sunburn), hair loss in the treated area, and temporary swelling.
• Site-specific effects: difficulty swallowing (head/neck), urinary changes (pelvis), or digestive upset (abdomen).
• Long-term risks: tissue scarring, secondary cancers (rare), or functional changes in organs near the treatment field.

Radiation therapy does not produce instant results. Tumor shrinkage and symptom relief often occur gradually over weeks or months. Regular follow-up visits and imaging tests assess effectiveness and monitor side effects. Supportive care (nutrition counseling, physical therapy, skin care, fatigue management) is provided throughout and after treatment.