18F- FDG-PET/CT for the diagnosis of tumor thrombosis.
BACKGROUND
Venous thromboembolism is a well-recognized and relatively frequent complication of malignancy, whereas tumor thrombosis is a rare complication of solid cancers. The correct diagnosis of tumor thrombosis and its differentiation from VTE can alter patient management and prevent unnecessary long-term anticoagulation treatment.


OBJECTIVE
To evaluate the contribution of 18F-fluorodeoxyglucose positron emission tomography/computed tomography to the diagnosis of tumor thrombosis and its differentiation from VTE.


METHODS
PET/CT scans from 11 patients with suspected tumor thrombosis were retrospectively evaluated. Suspicion arose from positive PET/CT in eight cases, or from findings on contrast-enhanced CT in three patients. Criteria for positivity of PET/CT included increased focal or linear uptake of 18F-FDG in the involved vessel. Findings were categorized as PET/CT positive, or PET/CT negative and compared to contrast-enhanced or ultrasound Doppler, pathology where available, and clinical follow-up.


RESULTS
Eight occult tumor thromboses were identified by PET/CT-positive scans. Underlying pathologies included pancreatic, colorectal, renal cell, and head-neck squamous cell carcinoma, as well as lymphoma (4 patients). Three thrombotic lesions on contrast-enhanced CT were PET/ CT negative, due to VTE (2 patients) and leiomyomatosis. Accuracy of PET/CT to differentiate between tumor thrombosis and benign VTE was 100% in this small study.


CONCLUSIONS
Contrast-enhanced CT defines the extent of thrombotic lesions, while the functional information from PET/CT characterizes the lesions. It appears that PET/CT may be helpful in the diagnosis of occult tumor thrombosis and its differentiation from VTE.
Department of Nuclear Medicine, Sheba Medical Center, Tel Hashomer and Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel tima.davidson@sheba.health.gov.il
Tima
T
Davidson
Orly
O
Goitein
Abraham
A
Avigdor
S Tzila
ST
Zwas
Elinor
E
Goshen
D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000000981:diagnostic imaging; D015331:Cohort Studies; D003937:Diagnosis, Differential; D004067:Digestive System Neoplasms / Q000000981:diagnostic imaging; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging; D008223:Lymphoma / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D013923:Thromboembolism / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18