Tender Papule Rising on the Digit: Pacinian Neuroma Should Be Considered in Differential Diagnosis

Pacinian corpuscles are sensory nerve-end organs located in the deep dermis and subcutaneous tissue of the palms or soles. Pacinian neuroma is an extremely rare feature, defined as hyperplasia or hypertrophy of Pacinian corpuscles. About half of Pacinian neuromas present with point tenderness. There have been a limited number of cases reported around the world. We observed a 45-year-old woman with an 8-month history of a tender whitish papule on her left thumb tip. Histopathologically, an enlarged hypertrophic Pacinian corpuscle in subcutaneous tissue, surrounded by numerous nerve fibers, was found. Herein, we report a case of Pacinian neuroma presenting as a tender papule on a fingertip that was clearly related to repetitive trauma at that site. This case shows that a meticulous history and histological examination can lead to an exact diagnosis and proper treatment.