PET-CT in recurrent ovarian cancer: initial observations

Noninvasive diagnosis of early recurrence of ovarian cancer is challenging due to the small size of peritoneal metastases. Small-volume disease may not be evident at anatomic imaging in patients with elevated serum tumor markers. Functional imaging in the form of positron emission tomography (PET) can help identify patients with recurrent tumor. However, lesion localization for possible surgical treatment is difficult with PET alone. Combined functional-anatomic imaging with fused PET and computed tomographic (CT) scans is feasible and may improve disease detection by increasing radiologic sensitivity and specificity. PET and PET-CT have a potential role in evaluating patients for recurrent ovarian cancer, particularly those with negative CT or magnetic resonance imaging findings and rising tumor marker levels. Fused PET-CT scans obtained with combined scanners can help localize pathologic activity and differentiate this activity from physiologic radiotracer uptake. Combined functional-anatomic imaging can also increase diagnostic confidence at CT. Further study is needed to determine the possible benefits of lesion conspicuity at PET and anatomic localization at CT on fused PET-CT scans.