Radiologic Analyses
DCE perfusion data was available in 15 of 16 ICI+SBRT patients pre-treatment, 16 of 16 ICI+ SBRT patients post-treatment, and 5 of 5 ICI monotherapy patients pre- and post-treatment. ADC maps were available in all 21 patients pre- and post-treatment. There was a significant difference in tumor volumes pre- and post-treatment (12.35 vs. 20.51; p=0.03 ). However, no statistically significant difference was found in the other imaging metrics (reported pre- vs. post-treatment): mean ADC (1.73 vs. 1.69; p=0.58 ), mean Vp (6.63 vs. 5.78; p=0.43) ; mean Ktrans (19.19 vs. 23.25; p=0.63 ). A post-hoc analysis comparing perfusion and diffusion imaging metrics between the ICI+SBRT and ICI monotherapy groups pre- and post-treatment demonstrated no statistically significant difference in imaging metrics after drug initiation (reported pre-treatment ICI+SBRT to post-treatment ICI+SBRT versus pre-treatment ICI to post-treatment ICI): mean ADC (1.73 to 1.74 vs. 1.73 to 1.51; p =0.18), mean Vp (7.39 to 6.04 vs. 4.35 to 4.98; p =0.80), mean Ktrans (20.64 to 25.85 vs. 14.85 to 14.93;p =0.46), tumor volume (13.25 vs. 22.33 vs. 8.74 to 13.20;p =0.61).