Purpose: The current study characterized pleural changes induced by talc
pleurodesis (TP), based on serial positron emission tomography/computertomography
(PET/CT) with F-18 fluorodeoxyglucose (FDG).
Materials and Methods: A total of 8 cancer patients who had both TP and
PET/CT and no evidence of active pleural involvement after TP were
retrospectively evaluated. Maximum standard uptake values, maximum
Hounsfield units (HU), and thickness were followed over time.
Results: The 8 patients had 25 PET/CT scans performed in an average of 22
months after TP. An increased FDG uptake was associated with an increase
in pleural thickness within 5 months after TP, and both parameters showed
statistical significance as compared with findings before TP. After 5 months
of TP, the standard uptake value appeared to persist or increase further, and
the pleural thickening stabilized. The formation of calcification was a slow
process and might lag behind the changes in FDG metabolism and pleural
thickness. The HU did not change significantly once pleural calcification had
been formed.
Conclusions: Knowledge of aforementioned pleural changes may help
differentiate TP induced pleural inflammation from pleural malignancy and
to avoid false-positive interpretation of FDG PET/CT exams.