The Role of Delayed ¹⁸F-FDG PET Imaging in the Follow-up of Patients with Alveolar Echinococcosis

Multimodality imaging in diagnosis and management of alveolar echinococcosis: an update

“…Imaging with delayed PET/CT (3 h after the injection) is recommended to avoid false negative results in cases remaining negative after standard imaging. A study stressing the increased sensitivity of delayed FDG PET showed that the use of delayed PET/CT together with cytology is a reliable method in patient follow-up (41). In a recent study, MRI findings were compared with PET/ CT, and the presence of parasitic microcysts (type 1, 2, and 3 lesions in Kodama's classification) was suggested to correlate with a metabolically active disease (42) (Fig.…”

Echinococcosis

“…In case of severe adverse effects of ABZ, switching to MBZ may be attempted; any recurrence of the adverse effect, however, imposes benzimidazole withdrawal (with unfortunately no alternative as for now). Discontinuation of benzimidazoles in selected cases of inoperable AE now seems possible, if both FDG-PET with delayed image acquisition and serology are negative (Caoduro et al 2013;Bresson-Hadni et al 2011;Crouzet et al 2010;Bardonnet et al 2013;Reuter et al 2004). In liver transplant patients, ABZ must be initiated before and reintroduced as soon as possible after transplantation and maintained for at least 2 years if all AE lesions were removed with the liver and lifelong in case of metacestode remnants or if new AE foci are discovered during follow-up ).…”

“…FDG is not actually uptaken by the metacestode but mostly by the periparasitic inflammatory infiltrate. FDG uptake is best revealed when "delayed" images are acquired, 3 h post-FDG injection (Caoduro et al 2013). …”

Cystic and Alveolar Echinococcosis: Fraternal Twins both in Search of Optimal Treatment

“…for life) may significantly prolong survival (10-year survival of approximately 80 %, compared with less than 25 % in historical controls) (Brunetti et al 2010). A more personalized medical treatment of inoperable AE patients seems now to be possible, thanks to the combination of sequential FDG-PET evaluation with delayed acquisition of images, 3 h after FDG injection, and of new serological markers, to better assess the 'activity' of the parasitic lesions (Caoduro et al 2013;Bresson-Hadni et al 2011;Crouzet et al 2010;Bardonnet et al 2013). Discontinuation of BZM after many years of treatment could be tried in selected cases when all 'activity markers' are negative (Caoduro et al 2013;Bresson-Hadni et al 2011;Ammann et al 1998;Bardonnet et al 2013;Reuter et al 2004).…”

“…Although FDG uptake does not actually reveal the metacestode, but is mostly associated with the periparasitic infiltrate by immune cells, this indirect approach may be useful and is best correlated with parasitic activity when 'delayed' FDG uptake images are analyzed, i.e. 3 h after FDG injection (Caoduro et al 2013). …”