ESTRO 2024 - Abstract Book

S175

Brachytherapy - GI, paediatric, miscellaneous

ESTRO 2024

Figure 1. Measured activity distribution from autoradiograph, overlayed with the H&E-stained histological section with contoured necrosis.

The pathologist reports the histological samples stained with CD-31 and CC-3 to show a vascular region at the periphery of the tumor that does not extend within its center, leading to an apoptotic and necrotic area at the center. The samples stained with H&E showed self-induced necrosis within the center of the tumors. The size of the necrotic regions had a statistically significant difference (p = 0.034) in the active tumor group compared to inert and control groups (figure 2). Further experiments are required to increase the sample size of the active groups.

Figure 2. Percentage of necrosis per tumor volume for each group.

Conclusion:

To conclude, the first in-vivo Alpha-DaRT source orthotopic intra-rectal L diff measurements of colorectal adenocarcinoma were completed. The L diff agrees with previously published literature for healthy muscle tissue and show a large L diff range for rectal tumors, indicating the importance of tumor specific treatment planning.