[Malignant oncocytoma of the mammary gland]. / Malignes Onkozytom der Brustdrüse.

Described in this paper is the morphological pattern of a malignant oncocytoma in the breast of a woman aged 70 years. The tumour parenchyma consisted mainly of epithelial cells grouped in nests or cords and surrounded by sparse fibrous stroma. The cells were quite large and pleomorphic, their nuclei being round or bizarre with prominent nucleoli. Electron microscopy revealed a conspicuously increased number of mitochondria and bundles of intracytoplasmic microfilaments.

[Oncocytic paraganglioma of the carotid body]. / Onkozytäres Paragangliom des Karotiskörpers.

One case of benign oncocytic paraganglioma which had originated from the non-chromaffin cells of the carotid body in a woman, 66 years of age, is described in this paper. The microscopic pattern of the tumor consisted mainly of large, round, eosinophilic cells arranged in solid nests and sheets. Pale rather than eosinophilic cells of polygonal shape were predominant in the peripheral areas. Ultrastructural analysis revealed the presence of three cell types: oncocytes, cells with electron-dense granules, 150 to 200 nm in size, and transitional forms between these two. Possible development of oncocytes from APUD cells is discussed.