ESTRO 2024 - Abstract Book

S4430

Physics - Machine learning models and clinical applications

ESTRO 2024

Out of the 25 reported toxicities, five fulfilled our screening criteria, which included weight loss exceeding 5% and events with a grade of ≥2. Among 32 patients, these toxicities counts were weight loss (20), xerostomia (15), pain (14), fatigue (12) and dermatitis (10). We then examined the correlations of these toxicities with changes in daily gamma and target and OAR dose metrics and volumes. Among the findings, we observed moderate and weak correlations between changes in gamma for the skin and the occurrences of weight loss (r²=0.5) and pain (r²=0.29), with the weakest correlation noted for dermatitis (r²=0.07). Additionally, weight loss strongly correlated with changes in GTV T gammas (r²=0.68) and volumes (r²=0.69). The CTV IR gammas also moderately correlated with weight loss (r²=0.47). Pain was also weakly correlated to the constrictor muscle gammas(r²=0.30). No correlations were observed in gamma changes to fatigue or xerostomia.

Conclusion:

Our findings provide insight into the intricate relationship of early toxicities to daily radiation dose delivery assessed through CBCT images. We observed that dynamic early toxicities, such as weight loss, pain, and dermatitis, are moderately correlated with skin and CTV HR1,HR2 gamma changes, while a strong correlation exists between GTV T gamma values and volumes in relation to weight loss. The absence of correlations to fatigue and xerostomia may be attributed to the more subjective nature of these reported effects, making specific patients’ effects less