This subcutaneous tumor was easily shelled out of a lower extremity of an adult. It measured 27 millimeters in greatest dimension.
David Bolick provided the glass slide for this case.

Direct scan that includes most of the tumor. It is sharply circumscribed and composed of lobules of basaloid cells.

This shows the interface of the tumor and the adjacent connective tissue. The collagenous tumor stroma in this area  forms a pseudocapsule. Some of the nests of primordial epithelium are associated with collagenous stroma and others are associated with loose connective tissue containing scattered fibroblasts.

This shows a retiform pattern of thin strands of basaloid cells separated by loose connective tissue that contains scattered fibroblasts. There is occasional condensation of the stroma against the epithelium. This is interpreted as primitive follicular differentiation.

The strands of basaloid cells are broader in this picture, and there is decreased cytoplasmic density centrally within some of these strands. However, this is not diagnostic for sebaceous differentiation or outer root sheath differentiation.

There are areas of unequivocal sebaceous differentiation. The stroma in this area is denser and more collagenous than that seen in the other pictures.

Higher power view showing sebaceous differentiation.

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