RESUMO
Although they have proven effectiveness, radiofrequency and microwave ablation techniques have a high rate of partial responses. Diagnostic studies that anticipate the changes in morphology are essential for earlier detection of residual viable tumor tissue or local recurrences to identify patients who will benefit from a new treatment. Our study has determined the diagnostic yield of PET/CT studies at baseline and follow-up and adequate time between them and the ablation intervention. Seven patients with single tumor lesion with a total of 8 ablations were included. CT and PET/CT studies were performed at baseline and follow-up after ablation. Average times between PET studies at baseline and follow-up and the ablative therapy were 1.8 and 3.4 months, respectively. Mean scores in metabolic activities of the PET at baseline and follow-up were 7.6 and 4.3g/ml of SUVmax, respectively. The Dual Time Point technique helped to identify viable tissue after ablation in 3 cases. Follow-up PET/CT studies have conditioned the various treatment strategies adopted by clinical oncologists. The high yield of the PET/CT study including the Dual Time Point technique may be considered as a study replacement of initial and follow-up Contrast-Enhanced CT before and after treatment with RFA and AMO, this achieving considerable reduction in the exposure to high radiation levels. We propose conducting the first PET/CT follow-up study at 3 months of the RFA and AMO.
