Cytologic Features of Lipogranulomatous Reaction in an Axillary Sentinel Lymph Node.
INTRODUCTION
Multinucleated giant cells (MGC) are a rare finding when evaluating axillary sentinel lymph nodes. Some are described as foreign body-type MGC accompanied by foamy macrophages. They have been rarely reported in nodes from patients in which a previous breast biopsy was performed. The tissue damage induced by biopsy results in secondary changes including fat necrosis and hemorrhage that can migrate to axillary nodes. In this report, we illustrate a lipogranulomatous reaction in cytologic samples obtained during a sentinel lymph node examination of a woman previously biopsied because of breast carcinoma. We have found no previous cytologic descriptions and consider it an interesting finding that should be known to avoid diagnostic misinterpretations.


CASE
A 51-year-old woman underwent mastectomy of the right breast with a sentinel lymph node biopsy at our medical center. One month before, a control mammography revealed suspicious microcalcifications and a vacuum-assisted breast biopsy resulted in a diagnosis of high-grade intraductal carcinoma with comedonecrosis. Surgery with a sentinel lymph node biopsy was performed. The sentinel node was processed as an intraoperative consultation. Frozen sections and air-dried Diff-Quik stained samples were obtained. They showed abundant lymphocytes with MGC and tumoral cells. MGC showed ample cytoplasm with evident vacuoles of variable size. Occasional hemosiderin-laden macrophages were also present. The complete histologic analysis and immunohistochemical studies revealed no malignant cells. Histologic analysis showed, in subcapsular location, occasional MGC phagocyting lipid droplets. Hemosiderin-laden macrophages were a common finding.


CONCLUSION
Lipogranulomas may appear at axillary sentinel lymph nodes because of fat necrosis induced by previous breast biopsy. The most important consideration is not confounding MGC with epithelial cell clusters. This can occur with not well-processed samples, especially if unmounted.
['Jimenez-Heffernan|Jose Antonio|JA|', 'Valdivia-Mazeyra|Mariel|M|', 'Muñoz-Hernández|Patricia|P|', 'López-Elzaurdia|Consuelo|C|']
D001943:Breast Neoplasms D018270:Carcinoma, Ductal, Breast D003937:Diagnosis, Differential D005260:Female D005629:Frozen Sections D015726:Giant Cells D006801:Humans D007430:Intraoperative Care D066292:Lipid Droplets D008207:Lymphatic Metastasis D008264:Macrophages D008408:Mastectomy D008875:Middle Aged D011237:Predictive Value of Tests D000071036:Sentinel Lymph Node D021701:Sentinel Lymph Node Biopsy
Cytology Sentinel lymph node Lipogranuloma Fine needle aspiration