Radioactive seed localisation Mr Paul Samson Breast and General Surgeon NZIMRT National Training Day, Invercargill August 2014

Problems with Wires Scheduling conflicts between radiology and surgery due to need for multiple procedures on day of surgery Inability to use wire localization for first theatre case in the morning Wire displacement or transection Wire entry site and wire tip often well removed from target lesion -> non-uniform specimen results Surgeon often unable to confirm exact site of lesion

Radioactive seed-localized lumpectomy Titanium seed containing 3.7 to 10.7 MBq 125I which has half life of 60 days and emits 27 keV of gamma radiation Technicium-99 has shorter half-life (6 hours) but stronger gamma emission of 140 keV. Tip of 18G needle occluded with bone wax, seed is loaded, and a stilette loosely placed into the needle USA protocols have seed placed within 5 days of surgery Seed is introduced under USS or MMG guidance. Angle of radiologists approach not limited.

Radioactive seed-localized lumpectomy Standard intra-op handheld gamma probe to localize the seed (settings 125I for seed or 99Tc for sentinel node) Incise directly over the lesion Gamma probe to guide resection with margin and confirm excision of lesion plus seed Specimen radiograph taken (optional) Seed removed by pathology and returned to nuclear medicine

Radioactive seed localisation Mayo Clinic technique Better cosmesis, no wire dislodgement worries, more comfortable for patient, easier scheduling of surgery Rapid learning curve, improved cosmesis No large multicentre trial, billing issues, radioactive substance regulations

Radioactive seed localisation. The end of Hookwires?

MSKCC Breast Seed Localization The items you touch, people you encounter, and clothes that you wear will not become radioactive. People who are in close physical contact with you may be exposed to very small amounts of radiation. While there is no evidence that this exposure causes harm, there are things you can do to minimize radiation exposure to others: Distance. The amount of radiation emitted from your body is very small. It decreases significantly at a distance of 1 foot from the implant site. There is almost no radiation reaching a distance of 3 feet away. Time. Radiation exposure to others depends on how long you remain in close contact with them. You will not harm anyone by hugging, kissing, or shaking hands. You should avoid placing an infant, child, or young animal on your chest for any longer than 30 minutes per day for the next month (30 days) or until the seed is removed during surgery.