PURPOSE: To evaluate the clinical and radiographic findings of localized foreign body (FB) granulomas onmammograms. MATERIALS AND METHODS: This study involved 13 patients with localized FB granulomas on mammograms;their history of mammoplasty or other plastic procedures was obtained by telephone interviews. Two radiologistsanalyzed the location and morphology of FB granulomas and the presence of associated linear densities orparenchymal distortion on mammograms. Four patients underwent ultrasonography. RESULTS: No patient had a historyof mammoplasty. All 13, however, had a history of plastic procedure, three to 22 (average, 12) years previously,as follows : foreign materials including silicone liquid and oil such as paraffin been injected into the anteriorneck area of nine patients, the infra-auricular area of two, and the nose of two. Multiple small, high-density,flocculent nodules representing FB granulomas were distributed bilaterally in nine patients; they were noted inthe upper inner portion of 11 of 26 breasts. In eight patients, mammograms showed linear opacities suggestingfibrosis. There was no calcification or parenchymal distortion. Though in three cases, the masses were palpable.Ultrasonography revealed several anechoic nodules with posterior enhancement in subcutaneous fatty layers, and inone, 0.2cc of oil droplet had been aspirated under ultrasonographic guidance. CONCLUSION: Localized FB granulomasof the breast could be caused by the migration of FB from cervicofacial areas. Mammography showed characteristicdistribution of upper inner portions, and the findings were similar to those of mild interstitial mammoplasty.