Clinical Nuclear Medicine

Skip Navigation LinksHome > March 2014 - Volume 39 - Issue 3 > The Additional Value of Attenuation Correction CT Acquired D...
Clinical Nuclear Medicine:
doi: 10.1097/RLU.0b013e3182a20d5c
Original Articles

The Additional Value of Attenuation Correction CT Acquired During 18F-FDG PET/CT in Differentiating Mature From Immature Teratomas

Cho, Arthur MD*; Kim, Se-woong BS; Choi, Jiyoun MD*; Kang, Wonjun MD, PhD*; Lee, Jong-doo MD, PhD*; Yun, Mijin MD, PhD*

Collapse Box


Introduction: Increased 18F-FDG uptake is often seen in soft-tissue components or in neuronal components of teratomas, which makes differentiation of mature and immature teratoma difficult using only 18F-FDG uptake. The distribution pattern of fat and calcification in teratomas is characteristic on CT, which can also be well seen on attenuation correction CT (AC-CT). We hypothesize that the fat and calcification distribution patterns on AC-CT taken during PET/CT will provide additional diagnostic information in differentiating between mature and immature teratomas.

Patients and Methods: This retrospective study included 34 patients (44 masses; mean age 32 ± 16.3 years, range 0.2–70 years) who underwent 18F-FDG PET/CT before surgical resection for teratomas. 18F-FDG equal to or higher than the liver was visually considered positive. AC-CT images acquired during PET/CT were reviewed for calcification and fat distribution patterns. AC-CT findings for immature teratomas were scattered fat and/or disperse coarse calcification. Pathologic results were categorized into mature and immature teratomas. SUVmax and AC-CT findings were correlated with pathologic results.

Results: Out of the 44 lesions, 11 teratomas were immature, with higher 18F-FDG uptake in these tumors (7.8 ± 4.10 vs. 2.1 ± 2.28, P < 0.001). SUVmax higher than 2.8 were 91% accurate, but fat and/or calcification patterns on AC-CT were extremely helpful in reducing false-positive findings based on 18F-FDG uptake alone.

Conclusion: Characteristic fat and calcification patterns on AC-CT of PET/CT were extremely helpful in differentiating mature from immature teratomas, especially in mature teratomas with increased 18F-FDG uptake. This can potentially reduce unnecessary radiation exposure from additional contrast-enhanced CT.

© 2014 by Lippincott Williams & Wilkins


Article Tools


Article Level Metrics

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.