Breast Cancer Radiotherapy: Patient Guide & Side Effects | IDCC

This guide explains why radiotherapy is given, who needs it, what the process looks like day-to-day, expected side effects, and how to take care of yourself during treatment.

1) Why radiotherapy is used in breast cancer

Radiotherapy reduces the risk of recurrence by treating microscopic cancer cells that may remain after surgery.

Radiotherapy may be advised:

• After breast-conserving surgery (lumpectomy): almost always recommended

• After mastectomy: in selected cases based on tumor size, lymph nodes, margins, and other risk factors

• For lymph node areas: when nodes are involved or risk is higher

• For symptom control (metastatic disease): to relieve pain (e.g., bone metastasis) or control local symptoms

Key point: The aim is to improve long-term control and survival while protecting heart and lungs as much as possible.

2) Who typically needs radiotherapy?

Your oncology team decides based on stage, surgery type, pathology, and recurrence risk. Common situations:

A) After lumpectomy (breast-conserving surgery)

• Radiotherapy to the whole breast is standard.

• A “boost” dose to the tumor bed may be added in many patients.

B) After mastectomy (post-mastectomy radiotherapy, PMRT)

Radiotherapy may be recommended if:

• Lymph nodes are involved (especially multiple nodes)

• Tumor is large

• Margins are close/positive

• Skin or chest wall involvement is present

• Certain high-risk features exist (your doctor will explain)

C) Regional nodal irradiation (RNI)

Radiation may include lymph node areas (axillary/supraclavicular/internal mammary) when indicated based on node status and risk profile.

3) When does radiotherapy start?

• Usually 3–6 weeks after surgery, depending on wound healing.

• If chemotherapy is planned, radiotherapy often starts after chemotherapy (in many protocols).

• If you need hormonal therapy, it can be started either during or after radiotherapy based on your oncologist’s plan.

Your team will coordinate the sequence safely.

4) Types of breast radiotherapy (in simple words)

Whole breast radiotherapy (WBRT)

• Treats the entire breast after lumpectomy.

Chest wall radiotherapy

• Treats the chest wall area after mastectomy.

Boost radiotherapy

• Extra dose to the tumor bed (where the tumor was removed).

Partial breast irradiation (selected cases)

• Treats only the area around the tumor bed.

• Not suitable for everyone; used in selected early-stage cases.

Modern techniques that improve safety

• 3DCRT/IMRT/VMAT: shapes radiation to match the target and protect organs.

• IGRT: image guidance before treatment to ensure accurate positioning.

• DIBH (Deep Inspiration Breath Hold): especially helpful for left-sided breast cancers to reduce heart dose.

5) Step-by-step: what happens during treatment?

Step 1: First visit (consultation)

Your radiation oncologist reviews:

• Surgery details and pathology report

• Need for breast/chest wall and lymph node radiotherapy

• Dose and number of sessions

• Expected benefits and side effects

Bring:

• Surgical notes, biopsy reports, final histopathology report

• Any chemo details

• Scan reports (if done)

Step 2: Simulation/Planning CT (the “mapping” scan)

This is not a treatment day—it is for planning.

What happens:

• You lie on a special CT table.

• Your position is carefully set (often with arms above head).

• Small skin marks/tattoos may be placed for daily alignment.

• A CT scan is done in the treatment position.

If left-sided breast:

• You may be trained for breath hold (DIBH).

Step 3: Treatment planning

A specialized team (radiation oncologist + physicist + therapists) designs a plan to:

• Cover target areas (breast/chest wall ± nodes)

• Minimize dose to heart, lungs, opposite breast, and skin folds

This planning can take a few days.

Step 4: Daily radiotherapy sessions

• Usually Monday to Friday

• Each session typically takes 10–20 minutes in the department

• The beam-on time is only a few minutes

• It is painless—like getting an X-ray (but stronger and precisely targeted)

You can go home afterward.

6) How many sessions will I need?

This depends on your plan and risk profile. Many modern schedules use:

• Shorter course (hypofractionation): often about 3–4 weeks

• Some cases may need longer schedules depending on nodal treatment, boost, reconstruction considerations, or specific protocols.

Your doctor will tell you the exact number.

7) Will radiotherapy make me radioactive?

No. External beam radiotherapy does not make you radioactive. You can safely be around family members, children, and pregnant women.

8) Common side effects (what’s normal)

Most side effects are temporary and improve within weeks after radiotherapy.

A) Skin changes (most common)

• Redness (like sunburn)

• Dryness, itching

• Darkening of skin

• Peeling (in skin folds or under breast)

B) Fatigue

• Many patients feel tired, especially after 2–3 weeks.

• Usually improves after treatment ends.

C) Breast/chest wall changes

• Swelling or heaviness

• Mild tenderness

• Temporary firmness

D) Throat irritation (if nodes treated)

If radiation includes lower neck/supraclavicular area, you may feel:

• Mild sore throat

• Swallowing discomfort
  (not in all patients)

9) Less common but important side effects (rare with modern planning)

Your doctor will discuss these based on your specific plan.

• Arm swelling (lymphedema): risk may increase if nodes are treated and after axillary surgery.

• Shoulder stiffness: from positioning or radiation near shoulder structures.

• Lung inflammation (radiation pneumonitis): uncommon; may present as dry cough or breathlessness weeks to months later.

• Heart effects: rare with modern techniques; especially minimized with DIBH for left breast.

• Rib tenderness/fracture: very rare.

• Skin telangiectasia or long-term pigmentation: possible but usually mild.

• Second cancer risk: extremely low, and benefits outweigh risks.

10) How to take care of yourself during breast radiotherapy

Skin care (very important)

• Wash gently with mild soap; pat dry (don’t scrub)

• Moisturize with doctor-approved cream (avoid applying right before the session; keep a gap of a few hours)

• Wear soft cotton clothes and a well-fitting supportive bra (no tight straps)

• Avoid talcum powder, perfumes, deodorants on the treated area unless allowed

• Avoid hot water, heating pads, and harsh rubbing

• Protect from sunlight (cover area; use sunscreen only if advised)

Manage fatigue

• Short walks daily if possible

• Hydration and adequate sleep

• Light balanced meals with protein

Nutrition tips

• High-protein diet helps healing (dal, दूध/दही, paneer, eggs, fish/chicken if you eat non-veg, sprouts)

• Plenty of fluids

• If appetite reduces, eat small frequent meals

Exercise and arm care (especially if nodes treated)

• Gentle shoulder stretches as advised

• Avoid heavy lifting initially after surgery; follow physiotherapy guidance

• Watch for arm swelling; report early

11) When should I call the clinic urgently?

Call your oncology team if you have:

• Skin blistering, wet peeling, or severe pain

• Fever or signs of infection in skin folds

• Increasing breathlessness or persistent cough

• Sudden swelling of arm/hand

• Severe fatigue, dizziness, or inability to eat/drink

12) After radiotherapy: what to expect

• Skin may continue to darken for a short time, then gradually improves.

• Fatigue often improves over 2–4 weeks.

• Follow-up visits are scheduled to monitor healing, side effects, and cancer control.

• Continue systemic therapy (hormonal therapy/targeted therapy) as advised.

13) Frequently asked questions

Will radiotherapy affect my implants or reconstruction?

Radiotherapy can affect reconstructed tissue (especially certain implant-based reconstructions), sometimes increasing stiffness or contracture risk. Your team plans carefully and discusses expectations.

Can I work during radiotherapy?

Many patients continue work with adjustments, but fatigue may require flexible hours. Listen to your body.

Can I travel during treatment?

Daily sessions make long travel difficult. If travel is unavoidable, inform your team—treatment gaps are generally discouraged.

Is hair loss expected?

Radiotherapy causes hair loss only in the treated area. Head hair loss does not occur with breast radiotherapy.

Key takeaways

• Breast radiotherapy is a proven treatment that reduces recurrence risk.

• Planning is personalized and designed to protect heart and lungs.

• Side effects are usually manageable and temporary.

• Good skin care, nutrition, and gentle activity help you complete treatment comfortably.

Breast Radiotherapy at I D Cancer Centre, Lucknow

If you have a new diagnosis, a post-surgery radiotherapy plan, or want clarity on your report and options, we can guide you.