Clinical characteristics and differences of 802 acral tumours, categorized by anatomical sites.

BACKGROUND Acral skin tumours are common, but information in the literature regarding their incidence is scarce. AIM To investigate the clinical characteristics and differences in incidence of benign and malignant acral tumours by anatomical site. METHODS A retrospective review was conducted of 802 patients with acral skin tumours confirmed by skin biopsy between January 2010 and December 2019. Age, sex, duration, symptoms and sites were obtained from medical records and photographs. RESULTS The mean age of onset was 43.8 years, the male/female ratio was 1 : 1.41, and the mean duration was 68.8 months. Most tumours were asymptomatic (66.7%). In total, 802 acral tumours were identified: 512 (63.8%) were benign and 290 (36.2%) were malignant. The most common benign tumours were benign melanocytic lesions (n = 239), and the most common malignant tumours were melanoma (n = 234). The most common site was the sole (n = 408). Benign melanocytic lesions, melanoma and epidermal cysts were more frequent on the foot, whereas pyogenic granuloma, glomus tumours, haemangiomas and mucous cysts were more frequent on the hand. Glomus tumours, fibromas, mucous cysts and osteomas were more frequent on the nail portion, and benign melanocytic lesions and epidermal cysts were more frequent on the non-nail portion. CONCLUSION This study reports the incidence of various benign and malignant acral tumours according to site, and we believe the results will be helpful in making a clinical diagnosis.