Scintimammography in patients with minimal mammographic or clinical findings.

A prospective study was made of scintimammographic findings obtained in 75 patients with minimal mammographic or physical examination findings. Patients included those with a new mammographic nodule or density (n = 33), indeterminate calcifications (n = 15), a palpable abnormality with normal mammographic findings and normal or inconclusive ultrasonographic findings (n = 13), or a new lump or mammographic change at the site of prior surgery (n = 14). A positive scintimammographic focus was defined as a discrete, rounded lesion with increased uptake and could have an intensity ranging from low to very high. Of the 30 cancers diagnosed, 27 demonstrated a positive scintimammographic focus. Eight of these foci represented occult cancers that were not identified at mammography or physical examination, and 11 were smaller than 1 cm (down to 4 mm). The overall sensitivity and specificity of scintimammography were 90% and 93.8%, respectively, which suggests that this modality may be useful in the early detection of breast cancer. It can also help distinguish postsurgical and post-radiation therapy changes from carcinoma and may be of value in certain high-risk patients. Scintimammography is a useful, noninvasive method of evaluating patients with low-suspicion or indeterminate mammographic or palpable findings and can help detect additional small tumors.