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Radiotherapy Step by Stepุงู„ุนุฑุจูŠุฉ

Under physician review

Patient handout: Breast Radiotherapy

Radiotherapy Step by Step โ€” Designed for radiation oncologists to use in clinic

A local treatment that lowers the risk of disease returning after surgery, usually given over a few weeks.

Why radiotherapy is used

  • Breast radiotherapy is most often given after surgery (lumpectomy or mastectomy) to lower the risk of disease returning in the breast or chest wall.
  • It may sometimes include the nearby lymph nodes if needed.
  • The intent is usually curative and complementary to surgery; your doctor decides how much is needed based on the tumor type and surgical findings.

The area being treated

  • The remaining breast after lumpectomy, or the chest wall after mastectomy.
  • In some cases the lymph node areas around the collarbone or under the arm are treated.
  • An extra focused dose (a "boost") may be given to the original tumor site.

How to prepare

  • Wear a soft, wire-free cotton bra, or leave the area unpressured if that is more comfortable.
  • Use the moisturizer your team recommends, and avoid perfumes and deodorant on the treated area.
  • Avoid direct sun on the area, and protect it with sunscreen in future.
  • Do the recommended shoulder exercises to keep your movement supple.

Early (acute) side effects

  • Redness, dryness, and itching of the breast skin like sunburn, increasing toward the end of treatment.
  • Fatigue that builds up over the weeks.
  • Mild breast swelling or heaviness, and sometimes nipple tenderness.
  • Some throat irritation if nodes near the collarbone are treated.

Questions to ask your doctor

  • Will my treatment include the lymph nodes or only the breast?
  • How many sessions are in my plan, and is it a short or extended schedule?
  • Will we use breath-hold to protect my heart?
  • What is the best skin care for me during treatment?
  • What is my risk of arm swelling and how can I prevent it?

When to contact us immediately

  • Fever or signs of skin infection in the breast (marked heat, painful swelling, pus)
  • New shortness of breath or chest pain
  • Sudden, noticeable arm swelling
  • Severe ulceration or bleeding in the treated area that does not improve

If any of these appear, contact your treatment team immediately or go to the emergency department.