Squamous cell carcinoma arising from an epidermal cyst in the thumb.
BACKGROUND
Squamous cell carcinoma arising from an epidermal cyst is rare, and the most frequently affected region is the head and neck.


METHODS
A 41-year-old man noticed swelling and a small ulceration in the thumb pulp. A lesion with a 2-cm diameter was simply resected based on a diagnosis of infected epidermal cyst. Pathological diagnosis of the resected material was squamous cell carcinoma arising from an epidermal cyst. Consequent amputation was performed.


CONCLUSIONS
The clinical symptoms of squamous cell carcinoma arising from an epidermal cyst can mimic those of an infected epidermal cyst. The current report facilitates awareness of such disease.
Department of Orthopaedic Surgery, Kyushu University, Fukuoka, Japan. Electronic address: akio@med.kyushu-u.ac.jp.
Akio
A
Sakamoto
Department of Pathology and Oncology, University of Occupational and Environmental Health, Kitakyushu, Japan.
Eisuke
E
Shiba
Department of Pathology and Oncology, University of Occupational and Environmental Health, Kitakyushu, Japan.
Masanori
M
Hisaoka
Epidermal cyst; Squamous cell carcinoma; Thumb