Breast tumor localization using sestamibi

The sensitivity of sestamibi scanning is 85% for breast lesions that measure >or=1 cm in diameter. This detection technique complements mammography and clinical examination and can benefit patients with very dense breast tissue. An innovation in nuclear imaging uses a lead marker for localization.

A 53-year-old woman underwent scintigraphy to clarify the indeterminate findings of a mammogram. Left breast biopsies 7 and 8 years earlier had yielded benign results. Mammography revealed a somewhat asymmetric stromal pattern, but the tissue appeared stable compared with results of previous studies. No focal abnormalities were identified. The original sestamibi breast scan revealed focally increased sestamibi uptake in the left breast. She was referred for another sestamibi scan because no radiographic or palpable abnormality correlated with the scintigraphic findings, and the lesion was believed to be nonlocalizable. Histologic examination revealed high-grade, poorly differentiated infiltrating ductal adenocarcinoma.

After intravenous administration of Tc-99m sestamibi, the site of the lesion was identified using a lead marker, the persistence scope, and localization needles. This facilitated surgical removal.

Using a lead marker allows placement of localization wires to guide surgical breast biopsy in patients whose lesions are visible by scintigraphy but not via mammography or palpation.