FDG Uptake in Tumor Thrombus in Inferior Vena Cava From Rectal Cancer on Positron Emission Tomography

Tumor thrombus formation in the right common iliac vein after radical proctectomy in a patient with rectal cancer: a case report

Background

Intravascular tumor thrombi are mainly found in patients with liver cancer or renal carcinoma but rarely occur in those with rectal cancer.

Case presentation

This is a case report of a 58-year-old woman with a swollen right lower extremity 14 months after radical resection for rectal cancer. Although ultrasonography indicated the presence of deep venous thrombosis (DVT) located in the right common iliac vein, interventional angiography showed that a circular mass, considered a tumor thrombus, was located in the right common iliac vein. The tumor thrombus was cured by interventional therapy, and the pathological report confirmed that the metastatic tumor thrombus originated from the rectal cancer. The patient underwent concurrent chemoradiotherapy and systemic therapy. However, right lung, retroperitoneum, and 2nd sacral vertebral metastases were discovered during follow-up.

Conclusion

The correct diagnosis of a tumor thrombus and its differentiation from DVT can prevent incorrect treatment and prolong the survival of patients with rectal cancer.

Diagnosis of portal vein tumor thrombosis in colorectal carcinoma in fluorodeoxyglucose positron emission tomography-computed tomography scan and its clinical implication

Hypercoagulable state is seldom associated with colorectal carcinoma either in the form of bland thrombosis or tumor thrombosis (TT). Venous TT should not be overlooked while deciding treatment of colorectal cancer due to its propensity to complicate the disease in terms of morbidity and mortality even in favorable prognostic case of colorectal cancer. Fluorodeoxyglucose positron emission tomography–contrast-enhanced computed tomography (FDG PET-CECT) scan has proven its role in staging of colorectal cancer and also to diagnose tumor venous thrombosis. Here, we are presenting a case of a 61-year-old male patient having adenocarcinoma of rectosigmoid colon, and on pretherapy FDG PET-CECT scan, he was found with portal vein TT and its related complication which is helpful for staging, treatment planning, and prognostication.

Tumor thrombus: incidence, imaging, prognosis and treatment

Intravascular tumor extension, also known as tumor thrombus, can occur in many different types of cancer. Those with the highest proclivity include Wilm's tumor, renal cell carcinoma (RCC), adrenal cortical carcinoma (ACC) and hepatocellular carcinoma (HCC). The presence of tumor thrombus markedly worsens prognosis and impacts treatment approach. Imaging plays a key role in its diagnosis. Endovascular methods also play a large role in treatment.

Colorectal cancer with venous tumor thrombosis

Colorectal cancer is seldom accompanied by venous tumor thrombosis, and little is known about the features of venous tumor thrombosis in colorectal cancer. However, some reports show that colorectal cancer patients can develop venous tumor thrombosis and warn clinicians not to overlook this complication. In this report, we perform a review of 43 previously reported cases and investigate the characteristics of colorectal cancer accompanied by venous tumor thrombosis. The histological type of more than half of the cases was moderately differentiated adenocarcinoma, which is known to be aggressive. Among 41 cases with available data on liver metastasis, eight patients had synchronous liver metastasis, and liver metastatic recurrence after surgical resection was indicated in 10 patients. This liver metastatic rate was high compared to general colorectal cancer. However, 11 of 43 patients with venous tumor thrombosis could survive for more than 2 years after the diagnosis, although five of the 11 patients had liver metastasis. A long survival can be anticipated for patients following complete tumor resection and adjuvant chemotherapy. A greater accumulation of cases will help elucidate the characteristics of colorectal cancer with venous tumor thrombosis and improve the treatment strategy.

The role of 18F-FDG PET/CT in differentiating malignant from benign portal vein thrombosis

AIMS

In this retrospective study, we evaluated the role of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in differentiating malignant from benign portal vein thrombosis (PVT) in patients with known malignant tumors.

METHODS

Seventy-two patients with histologically or clinically confirmed PVT and who had undergone (18)F-FDG PET/CT were included. Visual and semiquantitative analyses of PET/CT scans were performed. Metabolic activity was measured using the maximum standardized uptake value (SUVmax) by drawing the region of interest at the site of thrombosis. Receiver operating characteristic analysis was conducted to identify the optimal cutoff of SUVmax for detecting neoplastic thrombosis. Malignancy was defined using the following criteria: (1) visual analysis and (2) SUVmax >3.35. PET/CT results were confirmed with histopathological results and clinical and imaging follow-up.

RESULTS

The SUVmax of tumor thrombus (6.37 ± 2.67) was significantly higher than that of bland thrombus (2.87 ± 1.47; P < 0.01). The sensitivities, specificities, and accuracies for the two criteria were 91.5 % and 93.6; 64.0 and 80.0 %; and 81.9 % and 88.9 %, respectively.

CONCLUSION

(18)F-FDG PET/CT is a promising new method for distinguishing between portal venous neoplastic thrombosis and bland thrombosis using semiquantitative analysis, with the optimal cutoff value of SUVmax >3.35 as a criterion.

Incidental diagnosis of tumor thrombosis on FDG PET/CT imaging

OBJECTIVE

Clinical data are presented on patients with tumor thrombosis (TT) incidentally detected on FDG PET/CT imaging, as well as determining its prevalence and metabolic characteristics.

MATERIALS AND METHODS

Out of 12,500 consecutive PET/CT examinations of patients with malignancy, the PET/CT images of 15 patients with TT as an incidental finding were retrospectively investigated. A visual and semiquantitative analyses was performed on the PET/CT scans. An evaluation was made of the pattern of FDG uptake in the involved vessel as linear or focal via visual analyses. For the semiquantitative analyses, the metabolic activity was measured using SUVmax by drawing the region of interest at the site of the thrombosis and tumor (if any).

RESULTS

The prevalence of occult TT was 0.12%. A total of 15 patients had various malignancies including renal (1 patient), liver (4), pancreas (2), stomach (1), colon (1), non-Hodgkin lymphoma (1), leiomyosarcoma (1), endometrial (1), ovarian (1), malign melanoma (1) and parotid (1). Nineteen vessels with TT were identified in 15 patients; three patients had more than one vessel. Various vessels were affected; the most common was the inferior vena cava (n=7) followed by the portal (n=5), renal (n=3), splenic (n=1), jugular (n=1), common iliac (n=1) and ovarian vein (n=1). The FDG uptake pattern was linear in 12 and focal in 3 patients. The mean SUVmax values in the TT and primary tumors were 8.40±4.56 and 13.77±6.80, respectively.

CONCLUSION

Occult TT from various malignancies and locations was found incidentally in 0.12% of patients. Interesting cases with malign melanoma and parotid carcinoma and with TT in ovarian vein were first described by FDG PET/CT. Based on the linear FDG uptake pattern and high SUVmax value, PET/CT may accurately detect occult TT, help with the assessment of treatment response, contribute to correct tumor staging, and provide additional information on the survival rates of oncology patients.

Migrating tumor thrombus trapped within the greenfield filter of the inferior vena cava and depicted by FDG PET/CT

A 72-year-old woman with leiomyosarcoma of the left thigh underwent a whole-body FDG PET/CT for staging, which demonstrated a large FDG-avid tumor in the left thigh and tumor thrombosis involving the profunda femoris artery/vein and superior femoral vein. A Greenfield filter was placed in the inferior vena cava before the radical resection of the tumor and thrombosis. Postoperative PET/CT showed an FDG-avid embolus trapped within the solid apical cap of the filter in the inferior vena cava. It was unknown if the tumor embolus migrated to the inferior vena cava before or during the surgical procedure of radical resection.

Pediatric renal non-hodgkin lymphoma with inferior vena cava thrombosis

Involvement of kidneys in disseminated lymphoma is common. Primary lymphoma of the kidney is rare and has varied imaging characteristics. Abdominal lymphadenopathy can result in encasement and narrowing of the retroperitoneal vessels occasionally causing thrombosis. We present a 12-year-old boy with renal lymphoma and inferior vena caval thrombus; discuss the rarity of this presentation as well as other differential diagnosis and the need for confirmation of histopathologic diagnosis before instituting therapy in pediatric renal tumors.

Adrenal metastasis of breast cancer with involvement of the inferior vena cava

Tumour thrombosis of the inferior cava vein is usually associated with primary renal cell cancer. To our knowledge, this is the first case reported of adrenal metastasis of breast cancer extending into the inferior vena cava. There are few references in the literature documenting this extension with positron emission tomography (PET) and enhanced computed tomography (CT). The authors focus on the role of combined PET-CT imaging in the accurate detection of malignant thrombus.

The current role of PET-CT in the characterization of hepatobiliary malignancies

BACKGROUND

Surgery has become heavily dependent on accurate imaging in the assessment and treatment of suspected or confirmed intra-abdominal malignancy. Positron emission tomography-computed tomography (PET-CT) fuses uptake of a radiotracer combined with CT images to assess both functional tissue activity and anatomical detail. Since its introduction it has offered new ways of treating gastrointestinal cancers.

METHODS

The review analyses the present literature regarding the use of PET-CT in the assessment, diagnosis, staging and treatment of hepatobiliary malignancies.

RESULTS

PET-CT is widely used in pre-operative tumours staging for colorectal liver metastases. There is convincing data that it may also be applicable for neuroendocrine tumours, assessment of indeterminate pancreas lesions and clinical drug trials. PET-CT is of limited value in hepatocellular cancers, although new techniques in dual-tracer PET-CT may change this.

CONCLUSION

Knowledge of the strengths and limitations of PET-CT is important for all surgeons managing cancer of the hepatobiliary system. More clinical data are required on PET-CT, particularly its effect on long-term survival in PET-CT-staged patients undergoing resection.

(18)F-FDG PET/CT for discrimination between tumor extension and blood thrombus in pancreatic adenocarcinoma associated with portal vein thrombosis

Pancreatic cancer is a malignancy with an extremely poor prognosis. Less than 3 % of patients are alive 5 years after diagnosis. Pancreatic neoplasms represent a possible but uncommon etiology of portal venous invasion. It is important to differentiate the nature of the thrombus, if it is a bland thrombus or is a direct tumor extension. Intense uptake of 18F-fluorodeoxyglucose ((18)F-FDG) has been reported in portal vein tumor thrombus. We present a case of pancreatic adenocarcinoma and clinical findings of portal hypertension due to portal vein thrombosis. (18)F-FDG positron emission tomography (PET)/computed tomography (CT) evaluation discarded a tumor thrombus; imaging findings of the pancreatic tumor and the bland thrombus are presented.

Tumor thrombus in the inferior vena cava from colon cancer detected by 18F-FDG-PET

We present a case of inferior vena cava (IVC) tumor thrombus detected by fluorine- 18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET). A man underwent operations for the treatment of sigmoid colon cancer at the age of 63. Because tumor markers [carcinoembryonic antigen (CEA) and CA19-9] were increased at the age of 67, abdominal contrast-enhanced computed tomography (CT) was performed. CT revealed IVC dilatation, including a low-attenuation area. 18F-FDG-PET was performed to make the differential diagnosis between tumor thrombus and clot. 18F-FDG-PET showed that 18F-FDG had accumulated in the IVC region. We considered the IVC tumor thrombus because of the 18F-FDG uptake in the IVC region and the patient's clinical course. To our knowledge, there are a few reports concerning 18F-FDG-PET and IVC tumor thrombus. 18F-FDG-PET may be useful in diagnosing tumor thrombus.

Detection of tumour thrombus by 18F-FDG-PET/CT imaging

Tumour thrombus is a rare complication of many solid cancers including renal cell carcinoma, Wilms' tumour, testicular tumour, adrenal cortical carcinoma, lymphoma, pancreatic cancer, osteosarcoma and Ewing's sarcoma. We describe six patients who harboured occult tumour thrombus detected by fluorine-18 fluorodeoxyglucose (F-FDG) positron emission tomography (PET)/X-ray computerized tomography (CT) imaging as part of the staging investigations. Recognition of this rare complication by PET/CT can change the management plan and prevent unnecessary long-term anti-coagulation treatment because of wrong diagnosis of cancer-related venous thrombus.

Initial diagnosis and treatment follow up of neuroblastoma invasion of inferior vena cava with I-123 metaiodobenzylguanidine scintigraphy

Neuroblastoma is a common malignancy diagnosed during childhood. Metastatic neuroblastoma frequently involves regional lymph nodes, bone, and bone marrow. In contrast, neuroblastoma involvement of the inferior vena cava (IVC) is extremely rare. We report a case of neuroblastoma with IVC invasion visualized with I-123 metaiodobenzylguanidine (I-123 MIBG) scintigraphy during a diagnostic workup while a follow-up I-123 MIBG scan showed resolution of tumor uptake in the IVC with treatment.