Magnetic seed that makes breast cancer surgery far simpler
THOUSANDS of women with breast cancer could benefit from having a magnetic seed inserted to make surgery more accurate. Elizabeth Cozens, 78, a retired administrator from Manchester, had one before her surgery in September, as she tells CAROL DAVIS.
THE PATIENT
W hen a letter arrived in July, asking me to go to a breast screening, I was surprised — mammograms aren’t routinely offered to over-70s. As it turned out, there had been an error with the national screening programme and I was one of thousands who hadn’t received an invitation for my final screening at around age 70.
Ten days after the screening, I received another letter, inviting me to have a biopsy on my right breast, where they then found a tiny lump was cancerous.
I was shocked. Though I had been self-checking, this lump was so small — 12 mm — that I wouldn’t have felt it.
My consultant, James harvey, said he could remove it, along with a small margin of healthy tissue, and I wouldn’t need chemotherapy or radiotherapy. Thankfully, it hadn’t spread.
Mr harvey explained that they put a marker into the tumour before the operation to make it easier to find. This was traditionally done by putting a long wire into the breast on the day of surgery, using a mammogram X-ray or ultrasound to help direct it.
But he said the wire is very uncomfortable and the end sticks out of the breast, so it can move if it’s bumped, meaning the surgeon following the wire won’t be directed straight to the cancer and some could be left behind.
Instead, he would use a tiny magnetic seed injected into my tumour. It wouldn’t move and he could locate it using a magnetic probe. For me, it would be less painful and more accurate.
I had the operation on September 26. The day before, a radiologist injected the seed into my breast using a long needle guided by ultrasound. I had a local anaesthetic, but the sharp pain still made me gasp.
I had my lumpectomy the next day and left hospital the following morning with just a plaster on my breast — the scar was a tiny 2cm. I was told they found the cancer easily and removed it completely.
A week later, I went to an exercise class at the hospital and could already raise my right arm above my head. I felt great. I took it easy for a few weeks, but now, I’m back to my usual self.
I’ll take hormone-blocking medication for five years to reduce the chance of the cancer returning and also have annual mammograms. But I’m just so grateful they found the cancer.
THE SURGEON
James Harvey is a consultant breast surgeon at manchester University NHs Foundation Trust. There are 55,000 new cases of breast cancer in the UK each year but, thanks to screening and more sensitive mammograms, we are picking them up earlier, when they are easier to treat.
Most small breast cancers can be treated surgically with a lumpectomy, removing the tumour and a margin of healthy tissue around it.
Cancers smaller than 2cm are too small to feel or see from outside the breast, so we need to locate them before surgery. This usually means women need a scan on the day of surgery. In the past, we would put a 20cm needle, 1.5mm wide, into the breast and guide a medicalgrade steel wire through it.
The wire has a barb at the end that fixes in the tumour, so the surgeon can find it later on.
This is uncomfortable, despite the local anaesthetic, and stressful because, while about 3 to 5cm of the wire is in the breast, the rest sticks out. The patient must sit very still while waiting or transferring between hospitals.
In 2 to 3 per cent of women, the wire moves out of place, so it’s not an effective guide, and, when you start the surgery, you have to cut through more tissue to find the tumour. The wire will also not necessarily have been threaded through in the most direct route — especially if it was inserted during a mammogram, when the breast is squashed out of shape. Instead, I prefer to use a magnetic seed as a guide. Magseed is a spiral, about the size of a grain of rice, made from steel and iron oxide.
Its shape stops it moving once it’s inside the breast, so we can inject it into the tumour up to 30 days before the operation.
We find the tumour using ultrasound or an X-ray and give a local anaesthetic before injecting the seed into it through a long needle. Some centres use a radioactive seed, but these need careful disposal. Magseed instead uses magnetism.
On the day of surgery, I check that I can detect the seed: I use a probe that emits a magnetic field and beeps louder and higher as it nears the Magseed.
Then the patient has a general anaesthetic for the 40-minute operation. I choose a site where the scar will be hidden, under the breast or beside the areola. I make a 4 to 5cm incision and use the probe to find the seed.
The initial incision is about the same size, whether a guide wire or a seed is used, but if a wire is put in during a mammogram while the breast is squashed, we may have to travel 10 to 20cm through a large breast, following the wire, and take quite a lot of surrounding tissue. With a seed, we can use the shortest route.
I remove a circular section of breast tissue around the seed and tumour and remove the sentinel lymph node, which is where cancer would spread to first. Then I close the incision with dissolvable stitches.
I see the patient two weeks later, when the pathology lab has confirmed the cancer has been completely removed — in very early cancers, patients may not even need radiotherapy.
Magseed is now being offered at 12 UK sites and I would like to see it at many more. I am running a national audit to compare results for the wire and Magseed — so far, the only downside I see is that the latter isn’t suitable for patients with implants such as pacemakers.
magseed costs £250; a lumpectomy is £4,500 privately and £2,880 to the NHs.