Lipid-Rich Carcinoma
FREDERICK C. KOERNER
This rare variant of infiltrating ductal carcinoma features large cells with abundant cytoplasmic lipid that imparts a vacuolated or foamy appearance to the cytoplasm. The tumor was first described as “lipid-secreting carcinoma” by Aboumrad et al.1 in a case report. Subsequently, these authors found one other example among 100 breast carcinomas and estimated the frequency of lipid-rich carcinoma to be 1%, but it is clearly less frequent. Ramos and Taylor,2 who coined the less committal term, “lipid-rich carcinoma,” described 13 cases collected during a retrospective review of more than 900 mammary carcinomas. The authors demonstrated lipid only in the four cases available as unfixed specimens; the histologic pattern alone established the diagnosis in the other nine cases. Since the time of these reports, only a few additional examples have been described.3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21
CLINICAL PRESENTATION
With one exception,6 all adult patients have been women, whose ages ranged from 22 to 81 years. One patient was a 10-year-old girl.17 Most patients presented with a distinct palpable mass, usually in the upper outer quadrant. Attachment to the skin or areola with dimpling, retraction, and redness has been reported1,6,10,19 with ulceration and peau d’orange in some instances.11,14 Lipid-rich carcinoma involved the overlying skin and chest wall in a child.17 In one patient,21 the lipid-rich carcinoma coexisted with a conventional high-grade non-lipid-rich invasive ductal carcinoma.
Radiologic imaging has been described in only a few cases.3,9,10,15,20 Mammography revealed spiculated masses in three patients, and three tumors contained calcifications. Ultrasonography in one patient20 demonstrated an irregular hypoechoic mass with indistinct borders and heterogeneous internal echoes. Using magnetic resonance imaging (MRI), the same mass displayed rapid enhancement to a high intensity with a peak-and-plateau pattern of the time-intensity curve. A hypoechoic mass was seen in one other patient.3
GROSS PATHOLOGY
MICROSCOPIC PATHOLOGY
Histologic sections demonstrate a predominantly invasive carcinoma composed of sheets, nests, and cords of large, polygonal cells, which may have poorly defined borders. Malignant cells sometimes occupy ducts and lobules associated with the invasive component, and one case seems to represent an entirely noninvasive (in situ) form of lipid-rich carcinoma.20 van Bogaert and Maldague8 described three histopathologic patterns created by the malignant cells. The “histiocytoid” pattern, which represents the most common variety, consists of large cells with pale foamy cytoplasm and small dark nuclei that lack pleomorphism (Fig. 27.1). Cells with large irregular and bubbly vacuoles, pleomorphic nuclei, and prominent nucleoli characterize the “sebaceous” pattern of lipid-rich carcinoma. The third pattern consists of cells with apocrine qualities, which possess abundant, finely granular, eosinophilic cytoplasm and nuclei with coarse chromatin and prominent nucleoli. Cells with these different appearances sometimes mingle in a single carcinoma. One can usually detect mitotic figures without difficulty,12,
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
