case_images: PMC10547860_01
case_images: (A) 18 Fludeoxyglucose PET-CT with cross sectional imaging on the left demonstrating an FDG avid portocaval lesion with a standardized uptake value of 18.7 (white arrow). Right figure demonstrates resolution of the FDG-avid lesion after SBRT. (B) Timeline of ctDNA changes during and after SBRT. Levels of ctDNA are quantified by mean tumor mutation per milliliter (MTM/mL).
case_images: fonc-13-1276729-g001.jpg
case_images: PMC10547860_01_fonc-13-1276729-g001.jpg
case_images: f1
case_images: Subsequent PET-CT after 9 months demonstrated an interval enlargement of a portocaval lymph node measuring 3.0 x 2.2 cm with a standardized uptake value (SUV) of 18.7 ( Figure 1A ). Monitoring of ctDNA during radiation treatment demonstrated increased levels followed by undetectable levels ( Figure 1B ). Repeat PET-CT after 2 months of SBRT demonstrated complete resolution of excessive FDG avid uptake in the portocaval lymph node ( Figure 1A ).
case_images: PMC10547860_02
case_images: (A) 18 Fludeoxyglucose PET-CT with cross sectional imaging on the left demonstrating an FDG avid aortocaval lesion with a standardized uptake value of 21.8 (white arrow). Right figure demonstrates resolution of the FDG-avid lesion after SBRT. (B) Timeline of ctDNA changes during and after SBRT. Levels of ctDNA are quantified by mean tumor mutation per milliliter (MTM/mL).
case_images: fonc-13-1276729-g002.jpg
case_images: PMC10547860_02_fonc-13-1276729-g002.jpg
case_images: f2
case_images: He resumed maintenance nivolumab, which was continued for 3 years at which time PET-CT demonstrated a FDG avid aortocaval lymph node measuring 1.7 x 1.6 cm with SUV of 21.8 ( Figure 2A ). However, tumor-informed ctDNA was positive and quantified at 20.92 MTM/mL ( Figure 2B ). Further longitudinal monitoring of ctDNA was undetectable for 10 months ( Figure 2B ), and there was no evidence of disease recurrence on imaging surveillance.