Role of fluorine-18 fluorodeoxyglucose positron emission tomography in a case of renal cell carcinoma to differentiate tumor thrombus from bland thrombus

Abstract

Tumor thrombus is a rare complication of many solid tumors. We present a case of renal cell carcinoma whose baseline contrast-enhanced computerized tomography (CT) revealed an heterogeneously enhancing mass in the upper half of right kidney with tumor thrombus in the right renal vein extending to suprarenal inferior vena cava (IVC), crossing the cavoatrial junction and reaching up to the right atrium (Grade IV). Fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT imaging revealed large irregular right renal mass, hypermetabolic tumor thrombus extending from the right renal vein to suprarenal IVC reaching up to the right atrium. There was no FDG uptake noted in the infrarenal IVC and bilateral iliofemoral venous thrombi. Thus, 18F-FDG PET/CT was not only helpful in the staging, but was also helpful in differentiating tumor thrombus from bland thrombus in our patient.

Role of FDG PET-CT in Distinction of Benign Thrombus and Tumor Thrombus in Oncological Patients

“…In a similar study in the literature for distinguishing benign and malignant tumor thrombus reported 71.4% sensitivity and specificity values of % 90 with SUVmax cut-off value of 3.63, while in another study cut-off value has been reported as 2.25 [14][15][16]. A recent study of 12 patients on the efficacy of FDG PET/CT for assessing the acuity of DVT found similar results with regards to BT with mean SUVmax of 2.41 [17].…”

“…TT is mostly an insidental finding in CECT. Tumor thrombus is rarely seen in solid tumors such as mostly in hepatocellular carcinoma (ca) and renal cell ca, followed by ovarian/testicular tumors, colon ca, pancreas ca, lung, breast, thyroid tumors, lymphomas, sarcomas, neuroendocrine tumors [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Maximum standardized uptake value (SUVmax) is semiquantitative parameter that reflect metabolic activity, but is not specific marker of malignancies.…”

“…However, high FDG accumulation in a thrombus generally indiates a tumor thrombus. In a recent interesting image report from Sonavane SN et al, the authors reported the imaging findings of a patient with RCC where PET/CT not only ruled out locoregional adenopathy and distant metastases, but also distinguished tumor thrombi from benign thrombi in the same patient [16].…”

Vena Cava Inferior Tumor Thrombus Extending to Left Atrium in a Pediatric Patient diagnosed as Wilms Tumor

“…FDG PET-CT is a proven procedure in staging, restaging, diagnosis and treatment response in oncological patients. In a recent interesting image report from Sonavane SN et al, the authors reported the imaging findings of a patient with RCC where PET/CT not only ruled out locoregional adenopathy and distant metastases, but also distinguished tumor thrombi from benign thrombi in the same patient (1). In a similar study in the literature for distinguishing benign and malignant tumor thrombus reported 71.4% sensitivity and specificity values of % 90 with SUVmax cut-off value of 3.63, while in another study cut-off value has been reported as 2.25 (2-3).…”

Glomus Jugulare Tumor Presenting as Deep Vein Thrombosis

“…[21] Furthermore, tumor thrombus has the presence of enhancement, vessel expansion, and uptake of fluorodeoxyglucose on positron emission tomography. [21,22] In our case, a spectral Doppler ultrasound was performed, which was helpful in identifying the IJV filling defect as a malignant lesion because of the presence of vascularity within the IJV thrombus. The presence of vascularity in a thrombus differentiates malignant thrombus from a bland thrombus.…”