What to expect from radiotherapy for breast cancer

Radiotherapy uses targeted radiation to treat breast tissue or the chest area where cancer cells may remain after surgery. Your team may also plan treatment for nearby lymph nodes when your diagnosis and operation make this appropriate. A planning appointment maps the treatment area, and small skin marks or a temporary positioning aid may help you lie in the same position each visit.

During treatment, you lie still while the machine delivers radiation. The session itself is brief, but visits can continue over a course set by your oncology team. The treatment does not make you radioactive. Common effects include warmth, redness or darkening, dryness, soreness, and tiredness in the treated area. Some effects appear gradually and may settle after treatment; your team will explain what to expect for your skin and breast shape.

Attend the planning visit in comfortable clothing and tell the team about breast implants, previous radiation, skin conditions, or medicines. Wash gently, pat the skin dry, and use only creams or dressings recommended by your radiotherapy team. Avoid rubbing the treated skin and protect it from strong heat and direct sun. Choose a supportive bra or soft clothing if the area feels tender.

Keep appointments and mention fatigue early, especially if it affects work, driving, sleep, or eating. Gentle movement, regular rest, fluids, and nourishing meals can make daily routines easier. Do not stop prescribed treatment or apply a new product to the treatment area without checking first. Your team can adjust advice when surgery, chemotherapy, or hormone treatment is part of your plan.

Contact your radiotherapy team promptly if the treated skin becomes very painful, wet, blistered, or increasingly swollen, or if you cannot keep the area clean and dry. Report fever, chills, sudden breathlessness, chest pain, or a rapidly worsening cough urgently. Seek emergency help for severe breathing difficulty, fainting, or chest pain that does not settle.

Ask which breast or lymph-node areas will be treated, how the plan fits with surgery and other medicines, and how long each visit and the full course may take. Ask which moisturiser is suitable, what skin changes should trigger a call, and whether you need special advice about work, exercise, travel, or a breast implant.