Purpose: To review the F-18 FDG PET/CT findings of metastatic ovarian tumors and to determine any correlation between FDG uptake by metastatic ovarian tumors and that by the primary tumors.
Methods: PET/CT performed from June 2005 to March 2011 on patients with metastatic ovarian tumors of gastrointestinal tract origin malignancies was analyzed retrospectively. The SUV(max) of metastatic ovarian tumors and primary tumors, when available, was measured.
Results: Thirty-two patients were included. Of the 32 cases, 20 had metastatic tumors in bilateral ovaries and 12 had in a single ovary. The mean SUV(max) of the 52 total lesions was 4.1 ± 3.1 (range 1.2-13.3), and 46 lesions showed a heterogeneous FDG uptake pattern. In 22 cases with available primary tumor SUV(max) values, there was a moderate positive correlation with the SUV(max) of the corresponding metastatic tumors (r = 0.559, p = 0.007). There was no significant correlation between the size and SUV(max) of metastatic ovarian tumors (p = 0.128). The mean SUV(max) of metastatic ovarian tumors from colorectal cancers was significantly higher than that of stomach cancers (p = 0.039).
Conclusions: Metastatic ovarian tumors showed FDG uptake of variable intensity, depending on the primary tumor type. The FDG uptake pattern was heterogeneous by PET imaging in vast majority of the cases. When the primary tumor demonstrates a low FDG uptake, careful evaluation is necessary since the metastatic ovarian tumors may also show low FDG uptake.