Adjuvant radiotherapy may not significantly change outcomes in high-risk cutaneous squamous cell carcinomas with clear surgical margins: A systematic review and meta-analysis

Supplementary Material
I. Table 1- PICOS
II. Table 2- Search Terms for Medline
III. Figure 1. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Flow Diagram: Searching methodology and screening process were utilized to screen and select eligible articles.
IV. Figure 2A-D. Disease-related Outcomes: subanalyses: 2A) All studies excluding those with mostly clear cases (surgery alone=24, surgery and adjuvant radiotherapy=10). 2B) studies with R0 cases only (surgery alone=16, surgery and adjuvant radiotherapy=6). 2C) studies with R0 + unknown margin status cases (surgery alone=24, surgery and adjuvant radiotherapy= 9). 2D) studies that did not include any cases of sentinel lymph node biopsy (SLNB) (surgery alone=24, surgery and adjuvant radiotherapy=11).
V. Table 3- Summary of main analysis and subanalyses- Chi square test