*4.6. Statistical Analysis*

Ordinal and continuous variables are presented as median (interquartile range, IQR) or mean ± standard deviation (SD). Change in % was calculated using the following formula: ((value of follow-up PET)/(value of baseline PET) − 1) × 100. The Mann-Whitney u test was used to compare mean percentage changes between DC and PD patients. Survival analysis using Kaplan-Meier analysis was performed for PFS and DSS according to the

mPERCIST and RECIST 1.1 criteria for 3 month and 6 month follow-ups. Quantitative survival data are given as median in months. Log rank test was used to compare survival rates between subgroups. *p*-values ≤ 0.05 were considered to indicate statistical significance. All analyses were performed using SPSS computer software (SPSS Statistics 25, IBM).
