Proliferating trichilemmal tumor of the nose
A 53-year-old woman presented with a one-year history of a gradually enlarging lesion on\nthe nose that was otherwise asymptomatic. The lesion had evidently been growing in the\nlast 3 months. She denied trauma or insect bite at this location. Her medical history\nwas unremarkable. On physical examination a localized, non-painful skin colored nodule\nwith a smooth surface, soft consistency, measuring 0.5 x 0.5 cm () was observed on the nose. There were no palpable\nadenomegalies. Total lesion surgical excision with a 0.5 cm margin of normal tissue was\nperformed. Hematoxylin-eosin stain revealed a multilobular, noncapsulated tumor\noccupying all the dermis (). Lobules were\nformed by peripheral palisading of small basaloid cells, differentiating towards large\nkeratinocytes with ample eosinophilic cytoplasm and abrupt keratinization without a\ngranular layer (). Areas of calcification\nwith cholesterol crystals were observed within the compact eosinophilic keratin (). The tumor cells showed moderate nuclear\natypia and scarce mitoses (). This was\nconsistent with PTT. Wide surgical excision with a 1 cm margin of normal tissue was\nperformed and no relapse was observed during the 8-month period of follow-up.