Case 64 - Discussion

Uploaded: 2007-11-28, Updated: 2007-11-28




  • Mostly located in the skin of the face, neck and scalp;

  • Multifocal tumors may associate with turban tumor, an autosomal dominant familial cylindromatosis, may also develop trichoepitheliomas, gene name CYLD, chromosome 16p;

  • "Jigsaw puzzle" growth pattern, angular cell nests are molded to each other;

  • Prominent fibrous matrix with deposits of eosinophilic, hyaline basement membrane material surrounding the tumor nests;

  • Two cell populations in each tumor cluster: a compact basaloid cell in the periphery and a polygonal cell with more amphophilic cytoplasm in the center. Tumor cells have dispersed chromatin with inconspicuous nucleoli and sparse mitoses. Hyalinized globules are common in the tumor clusters.


  • AFIP, non-melanocytic tumors of the skin, series 4;