Introduction: Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are among the most common malignancies in the United States. There are many potential management strategies for BCCs and SCCs, and the choice of management strategy for an individual patient is not straightforward. We aimed to comprehensively collect information on the comparative effectiveness and safety of each currently used therapeutic strategy for both BCC and SCC.
Data sources: We conducted literature searches in MEDLINE®, the Cochrane Central Trials Registry and Cochrane Database of Systematic Reviews, and Embase® up to March 2017. We also perused the reference lists of published relevant clinical practice guidelines and systematic reviews. We recorded information on recurrence, histologic clearance, clinical clearance, patient- or observer-rated cosmetic outcomes, adverse effects, quality of life, costs and resources, mental health, patient satisfaction, and mortality. We estimated intervention effects (differences in outcomes between treatments) and the mean frequency of the outcome with each treatment using network meta-analyses.
Results: We identified 58 randomized controlled trials and 51 nonrandomized comparative studies comparing 21 interventions in 9 categories. Nearly all reported results for recurrence or cure rate outcomes and adverse events, and many reported results for cosmetic outcomes. Few studies reported results using validated instruments for quality of life, mental health, or patient satisfaction with treatment. Data were sparse, especially for analyses at the individual-intervention level. For BCCs, surgical interventions and radiation were associated with lower recurrence rates than interventions that destroy lesions with heat or cold and photodynamic therapy (PDT), and may have lower recurrence rates than curettage. Recurrence rates did not differ significantly between imiquimod and excision. The data were not sufficient to draw conclusions about the comparison of curettage with interventions that destroy lesions with heat or cold, or PDT versus other intervention categories. For SCC in situ, interventions that destroy the lesions with heat or cold and PDT were associated with lower recurrence rates than 5-fluorouracil. Data on the relative effect of thermal interventions versus PDT were not precise enough to draw conclusions.
Conclusions: Based on sparse evidence, surgical and radiation treatments have lower recurrence rates than other modalities for the treatment of low-risk BCC, and PDT appears to have superior cosmetic outcomes. Large gaps remain in the literature regarding the comparison of individual interventions and SCC in situ, with very little or no information on immunocompromised patients, patients with limited life expectancy, and patients with specific lesion categories, including high-risk BCCs and invasive SCCs.
May 2019 update: an addendum is located at the end of the main report, before the appendixes.