1. 18F- FDG PET/CT in the Diagnosis of Tumor Thrombosis
T Davidson1, E Konen2 , O Goitein2,
A Avigdor3, S T Zwas1 , E Goshen1
Departments of Nuclear Medicine1,
Radiology2 and Hemato-Oncology3
Sheba Medical Center,
Tel Aviv University, Israel

2. Background Venous Thrombo-Embolism (VTE): well-recognized
relatively frequent
complication of malignancy
Tumor Thrombosis:
a rare complication in this condition

3. Background Largest series described six cases
of Tumor Thrombosis diagnosed
by PET with simultaneous CT
Lai P, et al.
Detection of tumour thrombus by 18F-FDG-PET/CT
imaging.
Eur J Cancer Prev Feb;16(1):90-4.

4. Aims The role of PET/CT in the diagnosis of Tumor Thrombosis
The Differential diagnosis of
Tumor Thrombosis
from Venous Thrombo-Embolism

5. Materials and Methods Retrospective study of PET/CT scans
10 patients with suspected intravascular
thrombosis on either PET/CT or
contrast enhanced CT scans
6 M, 4 F; Age (mean 53.5 y)

6. Materials and Methods In 8/10 pts the intravascular lesion was
an incidental finding on PET-CT scan
during investigation of patients with
known malignancy
2/10 pts were referred to PET-CT for
further evaluation of a known
intravascular lesion diagnosed
on CT /MRI

7. Materials and Methods Criteria for a positive PET :
Increased focal or linear uptake of
18F-FDG in the involved vessel
Standard uptake value (SUV)
above 2.5

8. Materials and Methods Findings were categorized:
PET positive (+) or PET negative (-)
Compared to
contrast enhanced CT
ultrasound doppler,
pathology when available,
clinical follow-up

9. Results 7/10 patients showed PET(+) with Tumor Thrombosis
The other patients
( with intraluminal vascular lesions on contrast-enhanced CT ) had negative PET(-) and Tumor
Thrombosis was ruled out

10. Results of the 7 positive PET on contrast-enhanced CT consistent
6 had intra-luminal vascular defects
on contrast-enhanced CT consistent
with thrombosis.
1 had a positive US-Doppler

11. Tumor Thrombosis in SMV 54y M with pancreatic carcinoma

12. Tumor Thrombosis in SMV 54y M with pancreatic carcinoma

13. Tumor Thrombosis in IVC 46y M with RCC

15. Results lesions on contrast-enhanced CT had a negative PET
3/10 patients with intraluminal vascular
lesions on contrast-enhanced CT had a
negative PET
in 2 patients blood clot was to be
confirmed
and 1 had intravenous leiomyomatosis

16. Blood clot in SMV 64y M with NHL

17. Intravenous leiomyomatosis in IVC , 49y F

18. Intravenous leiomyomatosis in IVC , 49y F

19. Results
PET/CT correctly differentiated
between Tumor Thrombosis and benign Venous Thrombosis in all our patients

21. Results Underlying pathology in 7 patients with Tumor Thrombosis
4 lymphoma
1 pancreatic ca
1 renal cell ca
1 head - neck squamous cell ca

22. Involved Vessel with Tumor Thrombosis
1 Jugular vein
1 Subclavian vein
2 SVC
1 SMV
1 Iliac vein
1 IVC

23. Potential Pitfalls False positive PET findings may be due to
inflammatory lesions ,
including infected catheters
in the venous vasculature

24. Potential Pitfalls to the size of the lesion, the avidity of the
In contrast, missed diagnoses may relate:
to the size of the lesion,
the avidity of the
underlying pathological
process to FDG

25. Conclusion
Contrast-enhanced CT defines extent of thrombotic lesions, while PET contributes the functional information of these lesions

26. Thank you