The Radiology Roundtable - Part Two: Seed placement technique and node marking

Following on from Part 1 of our Radiology Roundtable, Dr Katerina Ntailiani, Dr Mamatha Reddy and Dr Chin Ngsat down to debate the use of localisation seeds for new advanced procedures, whether stereotactic placement should be common practice and share their tips and tricks to provide a more patient-friendly experience.

When it comes to placing non-radioactive seed technologies the presence of an MRI artefact can sometimes be a concern. We asked our panel of speakers how they get around this issue.

 “Our current practice is that we put a hydrogen marker or coil marker up front, and then when she finishes her chemotherapy, she then comes back to us for Magseed insertion” explained Magseed® user Dr Ntailiani.

In contrast, Dr Ng currently uses RFID seed technology and explained that her unit have had to seek out new imaging methods to work around this issue.

“There’s been a few occasions when a RFID has been put in for NACT purposes, and then the patient undergoes the MR, and there’s big artifacts – so it’s completely nondiagnostic. But in those cases, we’ve had one patient that we have to then revert to a contrast enhanced spectral mammography.”

So what patients would be a clear and obvious fit for having a seed placed, irrespective of the technology used?

For Dr Reddy, who recently adopted the Magseed® marker and doesn’t currently use contrast enhanced mammography or ultrasound, she said she’d initially opt for patients with “single lesions with no hint of multifocality on their mammography” or “relatively big lesions which might be amenable to wide local excision but not necessarily needing chemotherapy.”

Placing seeds under stereotactic guidance is becoming more commonplace, so we asked the group about their experiences with this method, and any tips they could share. For Dr Reddy, the experience with Magseed® has been a positive one:

“I think we thought it might be more complex than it was, but we have the 12 centimetre introducer so we localise exactly the same way we localise for wire. It’s the same prep for the patient.”

However, for Dr Ntailiani of Guy’s and St Thomas Hospital, the use of the stereotactic machine has been less common due to access issues.“For us it seems like a rare occasion that we have to confide in the stereotactic method for localisation”she explained.

Bringing the session to a close, conversation turned towards the use of seeds for advanced techniques, in particular around neoadjuvant therapy and targeted axillary dissection (TAD). Dr Ntailiani has been performing it for some time and she explained the procedure.

“Before the treatment, the biopsy proven node is localized with a normal hydrogel clip marker, then we monitor the patients with MRI. We tend to place the Magseed after the end of the treatment and prior to surgery, by identifying the clip node and then placing the Magseed in the node. We have had wonderful results”

For Dr Ng and her team, the ATNEC trial, which registered its first patients earlier this year, could provide the perfect springboard to launch their first TAD cases.

“That will be the start [participating in the trial] and then we’ll see how things unfold in the future. It may well be that we will start adopting targeted axillary dissection as a whole unit.”

→ Watch part one of the Radiology Roundtable

→ Enquire about switching to Magseed® localisation today