Intralesional 5-fluorouracil as a management for cutaneous squamous cell carcinomas: A rural Australian retrospective...

While the gold standard treatment for cutaneous squamous cell carcinomas (cSCCs) is surgical removal, there is a risk of infection, cosmetic and functional deficits. Intralesional 5-fluorouracil (5-FU) has been shown to be a potential non-surgical treatment modality for cSCCs in the literature. The aim was to investigate the safety and feasibility of using intralesional 5-FU to treat cSCCs. A literature review was conducted and a retrospective case series analysed patients who commenced intralesional 5-FU treatment for at least one cSCC between 1 January 2018 and 1 January 2019 at a private clinic in Orange, Australia. Inclusion criteria include: at least one cSCC was treated; only intralesional 5-FU was used; and treatment was ceased due to complete or inadequate remission, or adverse effects. There were 15 patients (7 female, 8 male, 60-99 years) and 20 out 21 cSCC lesions (82.6%) cleared while one lesion (4.3%) recurred. Six lesions (26.1%) ulcerated, four lesions became infected (17.4%) and one patient had an allergic reaction. The average number of treatments required for clearance was four (range 1-35), and the average 5-FU dose used was 75 mg (range 50-150 mg). Across 25 studies, 656 out of 708 lesions cleared (92.66%). Adverse effects were self-limiting and mostly well-tolerated. Intralesional 5-FU is an affordable and non-invasive non-surgical treatment modality that appears feasible to use for cSCCs and has a relatively low treatment-associated morbidity. Future clinical trials can help develop a protocol to guide clinicians in its use.