Pathology of lymph nodes from patients with breast implants: a histologic and spectroscopic evaluation

There are only a few published reports describing the pathology of regional lymph nodes from patients with silicone breast implants. Systematic analytical chemical verification of foreign material has not previously been reported. In this study, biopsies of regional lymph nodes from 96 patients with breast implants were studied using conventional histology as well as laser-Raman microprobe spectroscopy and Fourier transform infrared microspectroscopy. Lymph nodes from 12 patients without implants served as negative controls. Foamy macrophages, ranging from rare scattered cells to confluent sheets, were observed in sections of lymph nodes from 91 patients with implants and only rare foamy macrophages were observed in sections from 4 patients without implants. Refractile material consistent with silicone was observed in sections from 86 patients with implants and in no sections from patients without implants. Fragments of foreign material consistent with polyurethane were observed in sections from 16 patients with implants and in no sections from patients without implants. Using spectroscopy, the presence of silicone was confirmed in 71 patients with implants, and the presence of polyurethane was confirmed in 2 patients with implants. Spectroscopy was negative for silicone and polyurethane in all patients without implants. In summary, regional lymph nodes from patients with breast implants often have histologic evidence of silicone migration. Characteristic histologic findings include foamy macrophages and refractile droplets of clear material. Polygonal fragments of polyurethane were observed in lymph nodes from a number of patients. This finding has not been previously reported. The presence of silicone and polyurethane was confirmed using confocal laser-Raman microprobe and Fourier transform infrared microspectroscopy. Other than two prior case reports, this is the first confirmatory evidence of silicone migration to lymph nodes in patients with breast implants and this is the first confirmatory report of polyurethane migration to lymph nodes.