Treatment of MEK inhibitor-induced paronychia with doxycycline.

A 12-year-old girl with neurofibromatosis type 1 and a large facial plexiform neurofibroma had been participating in a selumetinib clinical trial for the past 5 years. Despite decreased tumor size, she developed recalcitrant selumetinib-induced paronychia. Various antibiotics, topical medications, and surgeries were only minimally effective. Full-dose doxycycline resolved the paronychia, and sub-antimicrobial dosing has prevented recurrences for several months, permitting her to continue her selumetinib course.