Fibrofolliculoma / trichodiscoma pathology

Many authors believe that fibrofolliculoma and trichodyscomas represent different ends of the spectrum of the same entity. These can happen as singles papules on the face, or as multiple injuries. Multiple injuries can occur in isolation or represent part of Birt-Hogg-Dubé syndrome.

Histology fibrofolliculoma / trichodiscoma

The sections through the fibrofolliculoma show a proliferation of follicular epithelium surrounded by a peripheral fibrous sheath (Figure 1-3). the epithelial the threads are made of thin laces of epithelial cells. the stroma surrounding the epithelium can be densely fibrous and sclerotic or rather loose and contain mucin. The patient illustrated in Figures 1-3 was later found to have Birt-Hogg-Dubé syndrome.

Fibrofolliculoma lesions contain prominent epithelial strands that center around the infundibular portion of a hair. Trichodiscoma is primarily fibrous, often with only a surrounding epithelial collar.

Special studies for fibrofolliculoma / trichodiscoma

Generally none is needed.

Differential diagnosis fibrofolliculoma / trichodiscoma

Basal cell carcinoma (BCC): BCC shows the retraction between tumor cells and the surrounding stroma. BCC show more nuclear atypiaoften a infiltrative growth pattern.

Neurofollicular hamartoma - These are believed to be spindle cell Rich form of trichodiscoma by some authorities. the spindle cells often positive with S100 and CD34

Perifolicular fibroma - It can be a form of fibrofolliculoma. The peripheral fibrosis It surrounds normal hairs instead of the fine epithelial cords seen in fibrofolliculoma.