Tumor embolism

Pulmonary embolism Amniotic fluid embolism Tumor embolism... 

Noninvasive detection of vascular abnormalities is of the utmost importance in clinical imaging. Indeed, a lot of injuries and diseases manifest themselves through modifications of the vasculature [1,2]. For example, abnormal angiogenesis (blood vessel growth) is observed in the development of most tumors. Embolism and atherosclerosis also manifest themselves through alterations of the blood vessels, namely through occlusions. Hemorrhage could also be detected noninvasively, which is crucial in injuries or in diseases such as ulcers [1]. 

Future perspectives calibrated particles of polyvinyl alcohol or gelatin penetrate deeper into the vascular system due to lower viscosity. Risk of ischemia is probably higher, but no clinical experience reported. Palliative tumor embolization might be more efficient with calibrated particles, in analogy with uterine fibroid embolization. 

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... 

Lammer J, Justich E, Schreyer H, Pettek R (1985) Complications of renal tumor embolization. Cardiovasc Intervent Radiol 831-35... 

Fischedick AR, Peters PE, Kleinhans G, Pfeifer E (1987) Preoperative renal tumor embolization. A useful procedure Acta Radiol 28 303-306... 

Uterine leiomyomas, or fibroids, are the most common type of solid tumors in adult women, clinically apparent in at least 25% of those of reproductive age [24-26]. Abnormal menstrual bleeding, pelvic pain, and infertility are the most commonly experienced symptoms in these women. Uterine fibroids are the leading cause of hysterectomies performed in the United States, accounting for over 200,000 of these procedures each year. Other invasive surgical interventions for the treatment of uterine fibroids include myomectomy and uterine artery embolization. Leiomyomas are estrogen-responsive tumors that can be treated... 

No more than 107 cells should be injected i.v. as this results in pulmonary embolization. Typically, we inject 50,000-150,000 murine tumor cells i.v. however, with human cells, especially collogenase dissociated primary human tumor cells, higher numbers of cells are required. 

Lapis, K., Paku, S. and Liotta, L. A. (1988). Endothelialization of embolized tumor cells during metastasis formation. Chn. Exp. Metastasis 6, 73-89. 

A danger of embolization of arteries is reflux of the instilled ethanol and the possibility of embolization of arteries other than the targeted ones. Infarction of the left testis secondary to transcatheter embolization of a malignant left renal tumor with ethanol has been reported (2). Colonic infarction following ethanol embolization of a renal tumor has been attributed to a reflux of ethanol from the renal artery into the aorta (3). 

There have been three studies of the effects of percutaneous ethanol injections in the treatment of hepatocellular carcinoma, either alone (12,13) or in combination with transcatheter arterial embolization (14). The procedure was effective and safe and improved long-term survival. Adverse effects were generally mild and of short duration, and commonly included abdominal pain, fever, intoxication (especially among non-drinkers), transient rises in serum transaminases, and chemical thrombosis of the tributary branch of the portal vein. Hepatic infarction has been reported in two patients with hepatocellular carcinoma after percutaneous ethanol injection of the tumors (15). Both patients had previously been treated with transcatheter arterial infusion using a suspension of styrene maleic acid neocarzinostatin, and the liver damage may have occurred through a combination of arterial damage due to the neocarzinostatin and vasculitis caused by flow of the injected ethanol into a portal vein branch. 

Thrombosis and pulmonary embolism have been described with tamoxifen (27,28) the number of cases is smaU, but the association would not be unexpected in view of what is known about the effects of other sex hormones. The primary condition might be responsible, at least in part, for the occurrence of such complications. Tamoxifen does reduce antithrombin III but not to a degree at which a major risk would be expected, and other measurable effects on the coagulation process seem to be shght When tamoxifen 20 mg/day was compared with equief-fective doses of anastrozole in 668 patients with advanced breast tumors that were hormone receptor-positive or of unknown receptor status, tamoxifen produced too high a rate of thromboembolism and vaginal bleeding to be considered the treatment of choice (29,30). 

Several reviews of the adverse effects of vitamin E have been published (3,4), especially relating to premature infants (5), in whom high doses have been associated with infectious complications and fatal hepatic failure. In adults, thrombophlebitis, thromboembolism, pulmonary embolism, hypertension, fatigue, gynecomastia, and breast tumors have been described as particularly serious effects of vitamin E, but there is little evidence about their frequency. Diarrhea and abdominal pain can occur. For some of these effects there seems to be a dose relation. A dose of 800 mg/day for 30 days had no reported adverse effects in healthy elderly subjects (6). Table 1 shows reported adverse effects related to dosage in a review of about 50 publications on vitamin E (7). 

Komemushi A, Tanigawa N, Okuda Y, et al. A new liquid embolic material for liver tumors. Acta Radiol 2002 43(2) 186-191. Murdoch L-A. Dimethyl sulfoxide (DMSO) an overview. Can J Hasp Pharm 1982 35(3) 79-85. 

Hypervitaminosis E. This is a relatively safe vitamin. Toxicities have been reported involving chronic administration of 300-1200 mg per day. The symptoms can be very serious and include thrombophlebitis, pulmonary embolism, hypertension, breast development in men and children, severe fatigue, and nonmalignant breast tumors. Nevertheless, the UL to RDA ratio is about 66 to 1 for adults, making it a very safe vitamin. 

Arteriography of the gut depicts the configuration of visceral blood vessels after intravenous administration of a contrast medium. Arteriography may be employed for detecting tumors and bleeding lesions and therapeutic apphcations, including embolization of bleeding vessels, fistulas, and inoperable tumors. ... 

Thromboembolic phenomena, including thrombophlebitis and pulmonary embolism, have occurred on rare occasions. Nausea, vomiting, edema, breakthrough bleeding, dyspnea, tumor flare (with or without hypercalcemia), hyperglycemia, alopecia, carpal tunnel syndrome, and rash have been reported. 

Atrial myxoma is a rare atrial tumor that causes multiple emboli of either thrombus or myxomatous tissue. When myxomatous material is embolized from the left atrium into the brain arteries, they may cause the formation of multiple distal cerebral aneurysms with risk of hemorrhage [46]. Papillary fibroelastomas are rare benign cardiac tumors usually involving a heart valve. They are small vascular growths with marked papillary projections. They usually grow on the aortic or mitral valves. The tumor consists of fibrous tissue surrounded by an elastic membrane, which in turn is covered by endothelium. One of the most conunon clinical presentations is of transient ischemic attack or stroke [47,48]. 

Certain symptoms and side effects associated with cancer could be secondary to disease progression. For example, cancer metastases to the bones could cause chronic pain due to proliferation of cancer cells in the bones and the associated bone remodeling and destruction [89]. Also, tumors that compress veins, the use of central vein catheter [90], and relative immobility of the patient could lead to deep vein thrombosis with potential pulmonary embolism [91]. 

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