Summary of Methods Applied for PET/CT Response Definition
| PET/CT parameter | At each PET/CT scan | Response calculation |
| Highest SUVmax | Calculate SUVmax for all the lesions | For each patient, calculate the percentage change of post vs. baseline highest value [(P − B)/B × 100] |
| Select the highest SUVmax value (labeled as B if baseline and P if posttreatment scan) | Define the patient as responder if the change is ≤ −50% | |
| Define the patient as nonresponder if the change is > −50% | ||
| Highest TLG | Calculate TLG for all the lesions | For each patient, calculate the percentage change of post vs. baseline highest value [(P − B)/B × 100] |
| Select the highest TLG value (labeled as B if baseline and P if posttreatment scan) | Define the patient as responder if the change is ≤ −50% | |
| Define the patient as nonresponder if the change is > −50% | ||
| Total SUVmax | Calculate SUVmax for all the lesions | For each patient, calculate the percentage change of post vs. baseline sums [(P − B)/B × 100] |
| Sum up all the SUVmax values (labeled as B if baseline and P if posttreatment scan) | Define the patient as responder if the change is ≤ −50% | |
| Define the patient as nonresponder if the change is > −50% | ||
| Total TLG | Calculate TLG for all the lesions | For each patient, calculate the percentage change of post vs. baseline sums [(P − B)/B × 100] |
| Sum up all the TLG values (labeled as B if baseline and P if posttreatment scan) | Define the patient as responder if the change is ≤ −50% | |
| Define the patient as nonresponder if the change is > −50% | ||
| SUVmax by lesion | Calculate SUVmax for all the lesions (labeled as B1,2,..n if baseline and P1,2,..n if posttreatment scan) | For each lesion, calculate the percentage change of post vs. baseline SUVmax value [(P1,2,..n − B1,2,..n)/B1,2,..n × 100] |
| Define the patient as responder if the change is ≤ −50% in all the lesions | ||
| Define the patient as nonresponder if the change is > −50% in at least 1 lesion | ||
| TLG by lesion | Calculate TLG for all the lesions (labeled as B1,2,..n if baseline and P1,2,..n if posttreatment scan) | For each lesion, calculate the percentage change of post vs. baseline TLG value [(P1,2,..n − B1,2,..n)/B1,2,..n × 100] |
| Define the patient as responder if the change is ≤ −50% in all the lesions | ||
| Define the patient as nonresponder if the change is > −50% in at least 1 lesion |