A guide to removing your tumour with the Magseed® marker

Patient Guide

What to expect from surgery with the Magseed® marker


Undergoing surgery to have a breast tumour removed?

If you have been diagnosed with early-stage breast cancer or have a suspicious looking lump that has been identified as a possible tumour during screening, you may have been offered breast-conserving surgery – also known as a lumpectomy or partial mastectomy.

This is a surgical treatment that aims to completely remove the tumour in one piece and leave behind as much healthy tissue as possible. This technique is less invasive than having the whole breast removed (also known as a mastectomy), and often has better cosmetic outcomes.

Thanks to more regular screenings, breast tumours are now being picked up earlier than ever before, making more women eligible for breast conserving surgery. This is having the positive effect of improving outcomes, leading to more women surviving breast cancer that ever before.

What is a lumpectomy or partial mastectomy?

A lumpectomy or partial mastectomy is a breast cancer treatment which involves surgically removing the tumour in one piece, as well as a thin margin of healthy tissue around it to ensure no tumour cells are left behind.

The amount of tissue that is removed will depend on the size of the tumour and the surgeon’s ability to accurately locate it.

How the Magseed® marker is used

How will my surgeon remove the tumour?

In order for the surgeon to know the exact location of the lump, there are a number of aids that can be used to ‘mark’ it. One of these is the Magseed® marker.

The Magseed® marker will have been placed in the centre of your tumour well in advance of your surgery. Once you are in the operating room, your surgeon will first use your mammogram images to give a rough idea of where the tumour is located in your breast.

Then, using the Sentimag® probe, they will be able to accurately locate the seed with precision. This will help guide your surgeon on where to make the incision and also help to continually check throughout the procedure to ensure the whole tumour is removed accurately and completely.

➡️ To learn more about the Magseed® marker, please read our guide here.

The procedure - what to expect

The Magseed® marker is placed in radiology

With a ‘Magseed® localisation’ procedure you will book a placement appointment with your hospital or health centre’s radiology department, prior to any surgery. Please note that your Magseed® marker could be placed many weeks before your planned surgery date, at a time that suits you and your surgeon.

When it’s time to place the marker, an anaesthetic gel will be applied to the area of your body where the marker will be injected. Your radiologist will then use an ultrasound machine (or something similar) to identify the suspicious looking tumour found on your mammogram.

They will then insert the Magseed® into the lump, ensuring the seed is placed correctly and securely. This is a quick procedure, so your appointment should take no longer than 30 minutes.

From here, you’ll now be able to carry on life as normal up to your date of surgery. The Magseed® marker will cause no discomfort and it will not move out of place.

Removing the seed during surgery

The surgery to remove a lump containing a Magseed® marker is a routine procedure for a breast surgeon.

During the surgery, your surgeon will use a magnetic probe to locate the previously placed Magseed® marker in your breast – and use the magnetic signal to accurately guide them to the site of the lump. Once at the site, the lump will be surgically removed, removing as minimal breast tissue as possible.

With your Magseed® already placed, you will be ready to go straight through to the operating room at the agreed appointment time. Your surgeon will likely introduce you to your anaesthetist, before you are put under general anaesthetic.

What happens after the surgery?

Once your lump has been removed, it will be taken to pathology for closer examination, where it will be determined if your cancer has been removed in one piece.

If there is still some tumour left behind, your surgeon will be able to remove smaller ‘shaves’ of breast tissue to ensure all of it has been removed. The chances of leaving any of the tumour behind with the Magseed® marker has been shown to be very low.

Where can I find out more?

If you have any more questions about your Magseed® surgery, please do ask your surgeon or the hospital team.

Thousands of surgeons and radiologists from across the world now use the Magseed® marker. You can hear our interviews with a selection of these surgeons here. We also have a number of resources and stories on our website which feature more information about Magseed®.

We hope that the information above has helped you understand a little more about what’s involved in having a tumour removed with the help of Magseed®.