الفهرس 
Historical BackgroundOnly 14 pages are availabe for public view
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Abstract
Malignant hepatic disease is common, with secondary deposits being at least 30 times commoner than primary cancers. The primary malignant tumors are dominated by Hepatocellular carcinoma (HCC). By comparison, other primary tumors are rare or even very rare. The majority of primary malignancies of the liver are Hepatocellular carcinomas (HCC) (85%-90%), with cholangiocarcinoma, angiosarcoma, and hepatoblastoma being much less common. Hepatocellular carcinoma (HCC) is the most frequent primary tumor of the liver in adults. It accounts for up to 5.6% of all human cancers (7.5% among men and 3.5% among women). This neoplasm ranks as the fifth most common cancer in the world and the third most common cause of cancer-related death. The incidence of HCC is increasing both in Europe and the United States, and in the next 2 decades it is expected to reach levels comparable to those currently found in Japan. For these reasons, advances in prevention and treatment of this cancer are a major health priority.
The most common malignant tumors of the liver are metastatic lesions. The liver is a common site of metastases from gastrointestinal tumors, presumably because of dissemination via the portal venous system. The most relevant metastatic tumor of the liver to the surgeon is colorectal cancer because of the potential for curative resection. However, a large number of other tumors commonly metastasize to the liver. Included among these are tumors of the lung, prostate, breast, pancreas, stomach, kidney, cervix, and ovary.
Hepatocellular carcinoma (HCC) is a highly fatal cancer that affects approximately half a million persons worldwide (fifth most common cancer in men and ninth women). The epidemiology of HCC is characterized by significant variations according to age, gender, race, and geographic region. Approximately 80% of the cases arise in developing countries, particularly those of Southeast Asia and sub-Saharan Africa, however, worldwide the overall incidence of HCC appears to be increasing.
The natural history of early HCC is largely unknown. Most patients uncovered in this stage are currently treated. Several studies have described the natural course of patients with small HCC (<5cm). Some cases show a constant pattern of growth and others either a declining growth rate or a biphasic slow initial, followed by faster growth.
Surgical removal with resection of negative margins remains the optimal therapy for primary and secondary liver tumors. Therefore, preoperative knowledge regarding the number, size and location of liver lesions, as well as their location regarding major liver vessels and the biliary system, is crucial for a successful surgical removal. Unfortunately, many patients that undergo ”curative” liver surgery for primary or secondary malignancies will relapse due to undiagnosed small malignant lesions. Therefore, the goal of imaging methods is not only the characterization of the liver lesions and their anatomical locations but also the detection of small tumor burden. Because only a small percentage of patients meet the criteria for curative respectability due to advanced disease, alternative approaches have been developed. Among them, intravenous chemotherapy, chemoembolization, and minimally invasive methods such as percutaneous ethanol injection, therapy, radiofrequency ablation, cryoablation, microwave ablation, and interstitial laser coagulation are the most prominent. Diagnostic imaging represents a cornerstone in the indications for and in the follow up assessments after these therapeutical approaches
The persistent interest in improved and safer surgical treatments for malignant liver tumors in based on the fact that surgical extirpation or complete cytodestruction currently provides patients with the best chance for long term disease free and overall survival. This is true for disease confined to the liver, whether treating patients with primary or metastatic liver cancers
The management of hepatic malignancy has changed from a previously nihilistic approach to a more positive one. Every patient should be considered for curative surgical resection, either at first presentation or after cytoreductive treatment. The surgeon is faced with the challenge of adapting modern surgical techniques to increase resectability rates. Although the majority of patients are unsuitable for resection, effective palliation can be achieved using a wide variety of techniques. The rational implementation of these palliative modalities requires a multidisciplinary approach which provides the surgeon with the opportunity to play a key role in the ongoing management of these patients. The wider acceptance of these attitudes has been largely due to the publication of excellent results both for curative procedures and also for multimodality palliative interventions. Operative mortality for liver resections currently is below 5% but, unfortunately, curative surgery is only possible for a small number of patients presenting with hepatic malignancy . It is the prospect of increasing the number of patients able to undergo hepatic resection and rationalizing the management of the remaining majority of patients with unresectable disease that presents the surgeon with the greatest challenges and opportunities
The few past decades had seen revoultional advances in the in situ ablation of hepatic Malignancies that lead to the emergences of a wide variety, the aim of which ranges from total ablation to simple palliation.
These Modalities are:
8. Devascularization methods.
9. Intra-Tumoral injection.
10. Regional chemotherapeutic techniques.
A- Transarterial chemoembolization.
B- Intra arterial hepatic chemotherapy.
C- Isolated hepatic perfusion.
11. Radiotherapy.
12. Targeted therapy.
13. Physical methods.
A- Radiofrequency Ablation.
B- Interstitial laser hyperthermia.
C- Microware coagulation therapy.
D- Cryotherapy.
14. Biological therapy.
Recent progress in molecular and cell biology has opened the way to novel therapies based on biological modifiers, gene transfer, and autologous stem cells. It is possible now to transfer therapeutic genes to the tumor or precancerous tissue and control their expression for long periods of time. It is also feasible to generate autologous endothelial proginator cells that can be recruited by tumoral vessels acting as vehicles to convey therapeutic genes to the interior of the tumor mass. Combination of biological modifiers, gene therapy, and cell therapy will hopefully provide efficient means to combat inoperable neoplasms in a not-very-distant future