Figure 1
Axial low-dose CT image acquired in conjunction with PET
Dilated right CFV (arrow) compared to normal caliber left CFV (arrowhead).
Incidental detection of DVT on 18FDG-PET/CT
SectionCardiovascular
Case TypeClinical Cases
AuthorsLeo Jia BA1, Joyce Hsu BS1, Kandace Klein DO2, Darko Pucar MD PhD3, Skon Nazarian MD2
Connected authors
76 years, male
Clinical History
A 76-year-old African-American man with a past medical history of stage T2N0M0 muscle-invasive urothelial carcinoma treated with neoadjuvant chemotherapy followed by cystoprostatectomy with ileal conduit and pelvic lymph node dissection presented with right leg pain. Physical examination revealed right lower extremity pitting oedema.
Imaging Findings
18Fludeoxyglucose (18FDG)-PET revealed linear hypermetabolic activity (SUVmax 3.0) along the course of the right common femoral vein (CFV) (Fig. 1). Correlation with low-dose CT images obtained in conjunction with PET revealed dilation of the right CFV compared to a normal calibre left CFV that was suspicious for deep venous thrombosis (DVT) (Fig. 2). There was no evidence of recurrent malignancy on 18FDG-PET/CT imaging. On subsequent right lower extremity venous duplex ultrasound, grey scale demonstrated incomplete compression and intraluminal echogenicity; colour flow Doppler sonography noted incomplete colour fill of vessel lumen (Fig. 4). These findings are consistent with acute, partially occlusive thrombus involving the right CFV and femoral vein without involvement of the profunda vein or popliteal vein. CT abdomen/pelvis with contrast was obtained one week after treatment and showed continued presence of DVT.
Discussion
Background: DVT is the formation of a thrombus in a deep vein that can potentially lead to life-threatening complications such as pulmonary embolism [1]. DVT formation typically involves the combination of hypercoagulability, hemodynamic changes and endothelial injury as classically described by Virchow’s Triad [2].
Clinical Perspective: The typical clinical presentation of DVT involves pain, tenderness or swelling of the extremity and warmth, redness or discoloration of the overlying skin [3]. However, this clinical presentation varies significantly as only half of patients experience any signs or symptoms [4]. This variability in presentation has lead to the development of the “Wells Decision Rule” as an attempt to quantify the pre-test probability of DVT as well as the employment of the D-Dimer assay [5]. Nevertheless, only imaging studies such as ultrasonography can provide the definitive diagnosis of DVT [6, 7].
Imaging perspective: Final diagnosis of DVT was made by confirmatory ultrasound. This case was unusual in that the initial detection of the DVT was made on 18FDG-PET/CT. The increased avidity of the thrombus on 18FDG-PET/CT imaging (SUVmax 3.0) is likely due to neutrophil-dependent thrombus inflammation which is characteristic of recently formed thrombus [8]. A cut-off value of SUVmax 3.63 has been previously found to be 90% specific and 71.4% sensitive in differentiating tumor thrombus from benign thromboembolism [9]. Sharma et al. successfully detected occult vascular thrombosis using 18FDG-PET/CT. In this case, CT correlation was diagnostic for DVT, though ultrasound evaluation was also performed to confirm and to provide a baseline for future CT follow-up (Fig. 5).
Outcome: The patient was admitted for anticoagulation treatment. He was treated with a heparin drip as an inpatient and transitioned to enoxaparin as an outpatient.
Take home message: DVT is a fairly common, yet potentially life-threatening condition that is most often diagnosed using ultrasonography. Although it is fairly rare to identify a DVT on 18FDG-PET/CT imaging, radiologists should evaluate venous vessels of patients with prior cancer diagnoses as they are at an increased risk of developing DVT [10]. We hope that this report helps to familiarize radiologists with the appearance of DVT on 18FDG-PET/CT as a possible incidental finding.
Clinical Perspective: The typical clinical presentation of DVT involves pain, tenderness or swelling of the extremity and warmth, redness or discoloration of the overlying skin [3]. However, this clinical presentation varies significantly as only half of patients experience any signs or symptoms [4]. This variability in presentation has lead to the development of the “Wells Decision Rule” as an attempt to quantify the pre-test probability of DVT as well as the employment of the D-Dimer assay [5]. Nevertheless, only imaging studies such as ultrasonography can provide the definitive diagnosis of DVT [6, 7].
Imaging perspective: Final diagnosis of DVT was made by confirmatory ultrasound. This case was unusual in that the initial detection of the DVT was made on 18FDG-PET/CT. The increased avidity of the thrombus on 18FDG-PET/CT imaging (SUVmax 3.0) is likely due to neutrophil-dependent thrombus inflammation which is characteristic of recently formed thrombus [8]. A cut-off value of SUVmax 3.63 has been previously found to be 90% specific and 71.4% sensitive in differentiating tumor thrombus from benign thromboembolism [9]. Sharma et al. successfully detected occult vascular thrombosis using 18FDG-PET/CT. In this case, CT correlation was diagnostic for DVT, though ultrasound evaluation was also performed to confirm and to provide a baseline for future CT follow-up (Fig. 5).
Outcome: The patient was admitted for anticoagulation treatment. He was treated with a heparin drip as an inpatient and transitioned to enoxaparin as an outpatient.
Take home message: DVT is a fairly common, yet potentially life-threatening condition that is most often diagnosed using ultrasonography. Although it is fairly rare to identify a DVT on 18FDG-PET/CT imaging, radiologists should evaluate venous vessels of patients with prior cancer diagnoses as they are at an increased risk of developing DVT [10]. We hope that this report helps to familiarize radiologists with the appearance of DVT on 18FDG-PET/CT as a possible incidental finding.
Differential Diagnosis List
DVT of the right common femoral vein and femoral vein
Tumor thrombus
Metastatic urothelial cancer
Final Diagnosis
DVT of the right common femoral vein and femoral vein
References
[1] Beckman MG1, Hooper WC, Critchley SE, Ortel TL (2010) Venous thromboembolism: a public health concern. Am J Prev Med 38:S495–501 (PMID: 20331949)
[2] Bagot CN, Arya R (2008) Virchow and his triad: a question of attribution. Br. J. Haematol 143 (2): 180–90 (PMID: 18783400)
[3] Rathbun, S. (2009) The surgeon general’s call to action to prevent deep vein thrombosis and pulmonary embolism. Circulation 119(15), e480-e482
[4] Bauersachs, R. M. (2012) Clinical presentation of deep vein thrombosis and pulmonary embolism. Best Practice & Research Clinical Haematology 25(3), 243-251 (PMID: 22959541)
[5] Wells, P. S., Owen, C., Doucette, S., Fergusson, D., & Tran, H. (2006) Does this patient have deep vein thrombosis?. JAMA 295(2), 199-207 (PMID: 16403932)
[6] Selis, J. E., & Kadakia, S. (2009) Venous Doppler sonography of the extremities: a window to pathology of the thorax, abdomen, and pelvis. American Journal of Roentgenology 193(5), 1446-1451. (PMID: 1984766)
[7] O'Leary, D. H., Kane, R. A., & Chase, B. M. (1998) A prospective study of the efficacy of B‐scan sonography in the detection of deep venous thrombosis in the lower extremities. Journal of Clinical Ultrasound 16(1), 1-8. (PMID: 3150383)
[8] Hara T, Truelove J, Tawakol A, et al. (2014) FDG-PET/CT Enables the Detection of Recurrent Same-Site Deep Vein Thrombosis by Illuminating Recently Formed, Neutrophil-Rich Thrombus. Circulation 2014;130(13):1044-1052 (PMID: 25070665)
[9] Sharma, P., Kumar, R., Jeph, S., Karunanithi, S., Naswa, N., Gupta, A., & Malhotra, A. (2011) 18F-FDG PET-CT in the diagnosis of tumor thrombus: can it be differentiated from benign thrombus?. Nuclear Medicine Communications 32(9), 782-788 (PMID: 21799368)
[10] Hutten BA, Prins MH, Gent M, Ginsberg J, Tijssen JG, Buller HR (2000) Incidence of recurrent thromboembolic and bleeding complications among patients with venous thromboembolism in relation to both malignancy and achieved international normalized ratio: a retrospective analysis. Journal of Clinical Oncology 2000;18:3078-83 (PMID: 10963635)
Case information
| URL: | https://www.eurorad.org/case/13896 |
| DOI: | 10.1594/EURORAD/CASE.13896 |
| ISSN: | 1563-4086 |
License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Figure 2
Longitudinal colour Doppler image of right CFV
Colour flow sonography demonstrates partially occlusive DVT.
Figure 3
Transverse grayscale image of right CFV, with and without compression
No flattening of the right CFV was seen without (left) and with (right) compression.
Figure 4
Axial enhanced CT pelvis (delayed phase)
CT with contrast obtained one week after treatment was initiated reveals persistent thrombus in the right CFV (arrow).
Figure 5
Skull to mid-thigh PET MIP Image
Linear hypermetabolic activity in the right CFV and femoral vein (arrow). Excreted activity in the right lower quadrant ileal conduit, external bag, and tubing (arrowhead).
Axial low-dose CT image acquired in conjunction with PET
Dilated right CFV (arrow) compared to normal caliber left CFV (arrowhead).
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Longitudinal colour Doppler image of right CFV
Colour flow sonography demonstrates partially occlusive DVT.
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Transverse grayscale image of right CFV, with and without compression
No flattening of the right CFV was seen without (left) and with (right) compression.
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Axial enhanced CT pelvis (delayed phase)
CT with contrast obtained one week after treatment was initiated reveals persistent thrombus in the right CFV (arrow).
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Skull to mid-thigh PET MIP Image
Linear hypermetabolic activity in the right CFV and femoral vein (arrow). Excreted activity in the right lower quadrant ileal conduit, external bag, and tubing (arrowhead).
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.
Klein K, Department of Radiology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA; 2016.