Therapeutic Outcomes and Efficacy of Intralesional 5-Fluorouracil in the Management of Cutaneous Warts: A Multi-Centric Prospective Cohort Study

Background: Cutaneous warts are common viral skin infections caused by human papillomavirus (HPV) and often present therapeutic challenges due to recurrence and resistance to conventional treatments. Intralesional therapies, including 5-fluorouracil (5-FU), have emerged as promising alternatives, demonstrating targeted cytotoxic effects on infected keratinocytes. Previous randomized and comparative studies have reported favorable clearance rates and acceptable safety profiles for intralesional 5-FU in treating different wart types. Objective: to evaluate the efficacy and safety of intralesional 5-FU in the treatment of cutaneous warts and to assess treatment response, side effects, and recurrence rates. Methods: A multi-centric prospective cohort study was conducted on patients with clinically diagnosed warts at a dermatology outpatient clinic. This multicenter study was conducted across three dermatology centers in Cairo, Egypt. Patients received intralesional 5-FU (50 mg/mL) injections every two weeks for up to six sessions. Clinical evaluation included wart type, number, and response to treatment, categorized as complete, partial, or no response. Results: Sixty patients were included, with a mean age of 29.5 ± 8.8 years. The majority had plantar warts (56.7%). Complete response was achieved in 83.3% of patients, while 16.7% showed partial response. No recurrence was observed among completely cured patients. Pain was reported in all patients (100%), while mild erythema occurred in 13.3%. A significant association was found between treatment response and number of sessions (p = 0.006). Conclusions: Intralesional 5-FU is an effective and safe treatment modality for cutaneous warts, with high clearance rates and minimal recurrence. Despite mild local side effects, it represents a valuable therapeutic option, particularly for resistant cases.