Radiotherapy for DCIS

Radiotherapy is commonly recommended after lumpectomy for DCIS. It is not usually needed after mastectomy.

The aims of treatment are to:

• lower the risk of DCIS coming back
• reduce the risk of invasive breast cancer.

Radiotherapy reduces these risks by destroying any abnormal cells that may remain in the breast after surgery. These risks are reduced by at least half when you have radiotherapy.

When radiotherapy may not be recommended

Sometimes radiotherapy is not recommended for DCIS.

The benefit of radiotherapy is low if you have a low risk of the DCIS coming back. This usually means:

• your DCIS is small (just a few millimetres) and low grade
• the DCIS is removed with enough healthy tissue around the DCIS (‘clear margins’)
• you are over 70 when you are diagnosed.

The definition of ‘low risk’ of recurrence is not always clear.

If you choose not to have radiotherapy

Take time to discuss your decision with your treating team. If you are unsure, you might like to ask for a second opinion from a radiation oncologist.

If you decide you don’t want radiotherapy after lumpectomy, it is important that you receive close follow-up and monitoring. This may include:

• breast examination
• mammogram
• ultrasound
• MRI (rarely).

Tests and clinical trials

Your radiation oncologist is the best person to ask if any clinical trials are relevant for you. Find out about clinical trials.

Predictive test – DCISionRT®

A free test is available in Australia for women diagnosed with DCIS who have had lumpectomy. The DCISionRT® test from GenesisCare can help:

• predict whether radiotherapy is likely to be of benefit in addition to surgery
• assess the risk within 10 years of DCIS returning or progressing to local invasive breast cancer.

Ask your treating doctor if you may benefit from the test.

Find out about the DCISionRT® test or contact GenesisCare on 1300 086 870.