Radiation Treatment for Breast Cancer

Melissa James

Radiation Oncologist

August 2015

OUTLINE

• External Beam Radiation treatment.

(What is Radiation, doctor?)

• Role of radiation.

(Why am I getting radiation, doctor?)

• Radiation Scheduling.

(How often will I be going in?)

• Side effects of Radiation

(Will it burn me, will I glow I the dark?)

• What is new in Radiation?

BACKGROUND

• Surgery remains the mainstay of treatment for early breast cancer.

• Mastectomy

• Lumpectomy (breast conserving surgery)

• Adjuvant treatments play an important role in preventing relapses and

therefore preventing cancer death:

• Chemotherapy

• RADIOTHERAPY

• Hormone therapy

Radiation: The Process

RADIATION TREATMENT- THE PROCESS

Planning

Planning CT

Breast

treatment

Radiation: The Role

ROLE OF RADIATION IN BREAST CANCER

• Breast conservation

• Post mastectomy

• DCIS

• Palliation

ROLE OF RADIOTHERAPY IN EARLY BREAST CANCER

• Indicated in MOST WOMEN post lumpectomy (Breast

Conservation)

• Post surgery local recurrence 20-30%

• Radiation decreases the risk of tumour recurrence in the remaining

breast tissue

• This translates into a small survival advantage.

BREAST-CONSERVING SURGERY (BCS)

Meta analysis

There were 7300 women with BCS in trials of RT

5-year local recurrence risks (mainly in the conserved breast):

• 7% vs 26% (reduction 19%)

15-year breast cancer mortality risks:

• 30.5% vs 35.9% (reduction 5.4%, SE 1.7, 2p=0.002)

15-year overall mortality risks:

• 35.2% vs 40.5% (reduction 5.3%, SE 1.8, 2p=0.005)

EBCTCG Lancet 2005; 366: 2087-2106

ROLE OF RADIOTHERAPY IN EARLY BREAST CANCER

• Indicated in SOME WOMEN post mastectomy

• Recurrence of breast cancer in chest wall may be catastrophic.

• Chest wall recurrence is frequently associated with metastatic

disease

• Thus prevention of recurrence important

MASTECTOMY AND AXILLARY CLEARANCE: N+VE

Meta analysis

There were 8500 women with mastectomy, axillary clearance,

and N+ve disease in trials of RT

5-year local recurrence risks:

• 6% vs 23% (reduction 17%)

15-year breast cancer mortality risks:

• 54.7% vs 60.1% (reduction 5.4%, SE 1.3, 2p=0.0002)

15-year overall mortality risks:

• 59.8% vs 64.2% (reduction 4.4%, SE 1.2, 2p=0.0009)

• EBCTCG Lancet 2005; 366: 2087-2106

ROLE OF RADIOTHERAPY IN EARLY BREAST CANCER

• Indications for post mastectomy radiation treatment

• 4 or more nodes involved

• T3 (5 cms or larger)

• Close or involved margins

• Other factors

• 1-3 nodes positive considered

• High risk features: lymph vascular space invasion, grade three

ROLE OF RADIOTHERAPY IN DCIS

• DCIS treated with a WLE

• Reduces recurrences by 2/3

• 50% of the recurrences will be further in situ disease

• 50% recurrences will be invasive recurrences

• No overall survival benefit

• Consider for

• High grade

• Large lesions

• Close margins

ROLE OF RADIOTHERAPY IN PALLIATION

• Painful bone metastases (80% will have pain reduction)

• Brain metastases

• Spinal cord compression

• Skin metastases

• Skin/ nodal recurrences

• Bronchial obstruction

SO radiotherapy is a very well established

treatment in breast cancer

Radiation: The

Scheduling

SCHEDULING RADIATION TREATMENT

• Daily Monday to Friday

• Each treatment 15-20 Minutes

• “Beam on time” is for only a few minutes

• Most time is “set up time”

• Treatment duration

• Most commonly 16 fractions (3+ weeks)

• May also have 25 fractions (5 weeks)

HYPOFRACTIONATED RADIATION

• Why the move to shorter treatments for early breast cancer?

META ANALYSIS

Radiation treatment

Hypofractionated treatment

(>2Gy per fraction)

Conventional fractionation

(1.8- 2 Gy per fraction).

James ML, Lehman M, Hider PN, et al. Fraction size in radiation treatment for breast conservation in early breast cancer. Cochrane Database Syst

Rev 2010;(11):CD003860.

HYPOFRACTIONATION

• The meta analysis found no difference in local recurrence rates with shorter

fractionation.

• No difference in long-term cosmesis.

• Less short-term toxicity.

• A SHORTER, MORE CONVENIENT RADIATION SCHEDULE WITH EQUIVALENT

CANCER OUTCOMES

Radiation: The Side

Effects

RADIATION THE SIDE EFFECTS

• Acute (Happen during radiation treatment and

immediately after)

• Skin reaction

• Erythema

• Dry desquamation

• Wet desquamation

• Breast/ Chest wall discomfort

• Lethargy

(No Nausea, hair loss, radioactivity)

RADIATION THE SIDE EFFECTS

Erythema Wet desquamation

RADIATION THE SIDE EFFECTS

• Late (Happen 6 months following the radiation treatment)

• Skin

• Pallor, atrophy, telangiectasia

• Soft tissue

• Fibrosis

• Pulmonary Fibrosis

• Asymptomatic

• Lymphoedema (Only if nodes are treated)

• 10-30%

• Brachial plexopathy (Only if nodes treated)

• <0.1%

• Cardiac toxicity

• Left sided patients

• <1% excess cardiac mortality with modern radiation at 15 years

• Second malignancy (Radiation induced)]

• 1-2:1000 at 10 years

Radiation: What is new in

breast treatment?

WHAT’S NEW IN RADIOTHERAPY?

• Excellent local control and survival rates for early breast

cancer

• Focus of Research is in decreasing the potential toxicity

IMPROVING ACUTE SIDE EFFECTS

• A dressing has been shown to improve rates of wet desquamation in breast cancer

patients receiving radiation treatment1.

• The dressing is called mepitel

• This is being introduced for post mastectomy

patients in Christchurch hospital

1. Radiother Oncol. 2014 Jan;110(1):137-43. doi:

10.1016/j.radonc.2014.01.005. Epub 2014 Jan 30.

IMPROVING LATE SIDE EFFECTS

• Cardiac Toxicity

• Meta analyses have shown a greater breast cancer specific improvement with radiation

treatment but less benefit in overall survival

• This is at least in part related to cardiac toxicity.

• Cardiac toxicity may take years to develop and is of particular concern to younger

women undergoing radiation treatment.

• These patients may also be receiving cardio- toxic chemotherapy

IMPROVING CARDIAC OUTCOMES IN PATIENTS

• We now are better than ever able to see the heart position and model the dose to the

heart with planning software

• This allows us to shield the heart

• Move the radiation beams to shield the heart

• Set the patient up differently (prone technique)

IMPROVING LATE SIDE EFFECTS

• Deep inspiratory breath hold

• is a method of helping patients to

maintain a good lung expansion,

• which keeps the amount of heart in the

radiation field to a minimum.

MODERN RADIATION TREATMENT FOR BREAST CANCER

•Safe

•Effective

MORE INFORMATION

http://www.targetingcancer.co.nz/