Hypervascular tumor

Fig. 3.2. Axial and coronal sections in the early arterial phase (left), late arterial phase middle) and portal venous phase (right) in a female patient suffering from hepatocellular carcinoma (HCC) under treatment with transarterial chemoembo-lization (TACE). In the early arterial phase only the liver arteries are properly enhanced the portal vein and also the liver parenchyma are not yet opacified. The two HCC nodules in segment 2/3 and segment 6 (marked by large arrows) are also both not properly demarcated. The early arterial phase, therefore, is not suitable for detection of hypervascular tumors it is rather a CT angiographic phase and can be omitted in most cases. The most important phase for detection of hypervascular tumors is the late-arterial phase (also called arterial-dominant phase or phase of portal venous inflow). In this phase there is already enhancement in the portal-vein (small arrow in the upper row) and in the liver parenchyma. The liver veins are not yet opacified in this phase (small arrow in the lower row). Most hypervascular tumors reach their highest attenuation in this phase. In the portal venous phase enhancement of the liver parenchyma is highest, the vascular enhancement in the portal venous system and in the hepatic vein is similar. Hypervascular tumors show decreased attenuation compared to the late-arterial phase depending on the degree of wash-out they can be still hyperdense (as in this case), isodense (see Fig. 3.4) or even hypodense...

If structural abnormalities such as vascular malformations, hypervascular tumors, vessel wall irregularities suggesting erosion etc., are visualized, then we may try for a palliative embolization with Gelfoam or particulates. Rarely, curative embolization of an arteriovenous malformation or fistula is achievable with non-resorbable agents, such as glue or detachable balloons. 

Bleeding from hypervascular tumors, such as duodenal metastasis of renal cell carcinoma, can be stopped by palliative particulate embolization (Fig. 5.8), although other authors preferred Gelfoam [88,89). 

Fig. 5.8a-d. A 79-year-old male, who underwent a left nephrectomy for renal cell cancer 1 year previously, now presents with melena from bleeding duodenal metastases. a DSA of the common hepatic artery showing hypervascular tumor blush (arrows) in the duodenum, supplied by hypertrophied duodenal branches of the gastroduodenal artery. b,c Superselective visualization of two different tumor compartments (arrows) with a 2.7-F microcatheter (arrowheads), d Control DSA after injection of several millilitres of PVA 150-250 p and 250-355 p in four tumor feeders (two of them shown here), confirming tumor devascularization. After each injection of 0.5-1 ml of PVA, superselective DSA was performed to control flow arrest and prevent reflux of particulates. Patient stopped bleeding for about 7 months and was then retreated... 

Embolization Embolization of skeletal neoplasms was initially performed as an adjunct to surgical resection for hypervascular tumors to decrease operative blood loss (Chuang et aL 1981a Dick et al. 1979). Subsequently, this technique was adapted for palliation of pain caused by skeletal metastases (Feldman et al. 1975). At MDACC, most of the giant cell tumors in a group of 21 patients with these neoplasms were located in the sacrum, Oium, and thoracolumbar spine and had not responded to other forms of therapy. 

Finally, some authors caution against placing metalKc stents with hooks and barbs, which are designed to prevent migration, in hypervascularized or vascular tumors since reports of fatal hemorrhage due to stent erosion of vascular structures or hypervascularized tumors have been published (Maynar etal.1993). 

Fig. 29.1. A 64-year-old male patient suffering from hepatocellular carcinoma (HCC), based on a chronic viral hepatitis. The HCC in liver segment 5/6 with an adjacent satellite nodule is shown as a typical hypervascular tumor with mosaic appearance in the axial slice of an arterial-dominant CT scan of the liver (left). The same dataset was also postprocessed via vendor...

McGraw et al. (2002) found that intraosseous venography predicted the flow of PMMA during vertebroplasty in 83% of cases however, this has not been confirmed by other authors, and the use of preprocedural venography has largely been abandoned except in hypervascular tumors (Do 2002 Gaughen et al. 2002). The viscosity of the cement has been shown to represent... 

Fig. 2.5.3. Celiac angiogram obtained before chemoembolization shows normal anatomy, including common hepatic artery (CHA), splenic artery (SA) and gastroduodenal artery (GDA). Additional multiple small hypervascular tumors (arrows) can he documented...

Fig. 2.5.11a-c. Nonenhanced CT scan in a patient with liver metastases (arrows) from breast cancer shows after the first TACE course only moderate intra-tumoral lipiodol uptake (a) The hepatic angiogram shows hypervascular tumor staining in the liver dome (b). Nevertheless conspicuous shrinking of the tumor (arrows) can be observed after the third course of TACE (c)... 

Fig. 4.2a-e. A 73-year-old male patient with renal cell carcinoma, diabetes mellitus and cardiovascular comorbidity. Multiplanar reformat (MPR) in the coronal plane from a pre-interventional multislice spiral CT depicts an eccentric 3.6-cm tumor of the right kidney (arrows) (a). The patient was considered to be at high risk for surgery. Because of the size of the hypervascularized tumor, a tumor embolization was performed prior to RF ablation (b,c). An umbrellashaped RF probe was introduced percutaneously via a lateral approach (d). Four months after RFA the axial CT image shows no contrast enhancement in the tumor area (arrows), corresponding to complete tumor necrosis (e). A sufficient safety margin without contrast enhancement is visible... 

Fig. 10.1. Axial, venous phase, gadolinium-enhanced MRI of a patient with unresectable HCC showing a peripherally enhanced lesion (arrows) in the medial segment of the left lobe. Solid, well demarcated lesions such as this one respond better to TACE than do diffuse or multifocal lesions. Additionally, hypervascular tumors appear to respond better to TACE showing a higher degree of necrosis on follow-up MRI...

The differential diagnosis of FNH includes other hypervascular tumors such as hepatocellular adenoma, hepatocellular carcinoma (particularly fibrolamellar hepatocellular carcinoma), and hypervascular metas-tases (Table 9.2). 

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