[Marking of non-palpable changes in breast tissue].

The Danish national mammography screening programme leads to identification of an increased number of small non-palpable breast tumours, suitable for breast-conserving surgery. Accurate lesion localization is therefore important. The current standard is wire-guided localization and although effective it involves a risk of high rates of positive margin and re-operations. New methods are emerging and radioactive seed localization (RSL) seems promising with regards to re-operation rates and logistics. In RSL a small titanium seed containing radioactive iodine is used to mark the lesion.