Nuchal-type fibroma in two related patients with Gardner's syndrome

Nuchal-type fibroma is a distinct subcutaneous and dermal fibrous tissue pr oliferation that has been previously definitely identified in one patient w ith Gardner's syndrome and has been possibly present in two others. Gardner 's syndrome is an autosomal-dominant condition with variable expressivity t hat comprises epidermoid cysts, fibrous tumors, osteomas, intestinal polypo sis, as well as other findings. We report two cases of nuchal-type fibroma presenting in a 13-year-old boy in the right upper back and in his 60-year- old grandfather in the upper chest at the posterior axillary line. Both ind ividuals carried a diagnosis of Gardner's syndrome and neither of them had diabetes. Although the boy has as of now only presented with cutaneous mani festations of Gardner's syndrome, his grandfather has exhibited both cutane ous and intestinal evidence of this syndrome. In addition, the boy's mother and her sister have documented Gardner's syndrome. Light microscopic findi ngs of nuchal-type fibroma from both patients include paucicellular, haphaz ardly arranged collagen bundles with entrapped adipose tissue. A marked dim inution of elastic fibers was noted with Van-Gieson stains. The lesions wer e diffusely positive for CD34 and contained a few factor XIIIa-positive cel ls. Electron microscopic analysis revealed no differences between the colla gen comprising the nuchal-type fibroma as compared with control dermal coll agen obtained from skin away from the tumor. These cases strengthen the vie w that there is an association between nuchal-type fibroma and Gardner's sy ndrome.