Longitudinal melanonychia induced by capecitabine.

Capecitabine is an oral prodrug of 5-fluorouracil (5-FU), used in the treatment of metastatic colon and breast cancers; it is also under investigation for use in gastric cancers. Multiple cutaneous adverse effects have been reported with the use of capecitabine including acral erythema, pyogenic granulomas, inflammation of actinic keratoses, cutaneous and mucosal hyperpigmentation, leopardlike vitiligo, radiation recall, onycholysis, onychomadesis, and subacute cutaneous lupus. To our knowledge, no cases of capecitabine-induced linear melanonychia have been reported to date in the literature.