Hyperplastic pacinian corpuscles: an uncommonly encountered lesion of the hand

The occurrence of hyperplastic pacinian corpuscles in the hand is rare, with only 13 cases reported in the literature. We describe such a case in a 70-year-old male who had worked as a locksmith for many years. A grape-like cluster of firm, rice-sized nodules was discovered in the subcutaneous tissue of the finger following a glass-induced injury. Histopathological findings revealed pacinian corpuscles to be increased in size and number. Individual corpuscles consisted of a central nerve fiber surrounded by 35 to 60 concentric lamellae (normal controls from other specimens: 13–15 lamellae). The external corpuscular diameter ranged from 1.8 to 3.2 mm (normal controls from other specimens: 1.6 mm). Immunohistochemistry showed positive staining with Leu 7 antibody and anti-glial fibrillary acidic protein in the small nerves situated in the vicinity of the pacinian corpuscles, but not in the corpuscles themselves. The lesion reported here clearly differed from both neurofibroma with occasional pacinian differentiation and the so-called pacinian neurofibroma. There was no evidence of neurofibromatosis.