Supplementary Table 1. Results of the normality test as presented in Figure 1 (performed using the Shapiro–Wilk test). Supplementary Table 2. Results of the normality test as presented in Figure 2 (performed using the Shapiro–Wilk test). Supplementary Table 3. Testing the assumption of normality for Age and PET SUV variables in groups of patients with archival samples and patients with freshly collected samples. Supplementary Table 4. Results of the Brown-Forsythe test for homogeneity of variance among different groups for miR-326, miR-20a, and miR-128. Funding source: National Science Centre, Poland (project No. 2021/05/X/NZ5/00971).