Marking of nonpalpable breast lesions using a custom carbon suspension.

To review results of carbon marking in non-palpable breast lesions using a different type of a carbon suspension containing 0.5% polyoxyethylene sorbitan monooleate (PSM). Sixteen lesions of 16 patients with indeterminate or suspicious mammographic findings underwent stereotaxic carbon marking. With the aid of tracing of the carbon stains surgery was then performed. Pathology revealed malignancy in 26% of the cases and the missed rate by carbon marking was 6% (1 lesion). Carbon marking is an easier application compared to hook-wire systems in localizing occult breast lesions. PSM added to a 4% carbon suspension results in a more homogeneous suspension, prevents early precipitation and eases injection. Animal studies have shown that no local or peripheral tissue reactions are elicited with either pure PSM or in a mixture with carbon. We recommend addition of PSM to carbon marking suspensions.