Hepatic artery infusion of chemotherapy after liver resection

Abstract

Abstract Resection is the treatment of choice for patients with limited metastases to the liver from colorectal cancer. Because of new techniques for liver surgery, resection for liver metastases from colorectal cancer has become increasingly safe and more commonly performed. Because these resections are curative, instead of palliative operations, there has been a limitation on the number of metastases that can be resected. At first, in the 1960s, only solitary lesions were resected. Then, in the following decades, larger studies provided evidence that 2 to 3 lesions could be resected with the same 5-year survival as the solitary lesions. 1-3 In the last decade, some studies have shown similar results with more than 4 metastases, although most larger studies suggest that the 5-year survival goes down when there are more than 4 lesions resected (Table 1). 4,5 A study from Memorial Sloan-Kettering analyzed their patients who had hepatic resection of 4 or more lesions. In this study of 155 patients, 49 with 4 metastases had a actuarial 5-year survival of 33%, compared with a survival of 14% for those with 9 to 20 metastases removed. 6 In a recent analysis of a large intergroup study of the treatment of rectal cancer that followed almost 1,800 patients after primary resection for over 8 years, 43% (721 patients) had disease recurrence. 7 Of these patients, 530 or 73.5% of all patients with recurrences had a single site of recurrence that was in the liver, lung, or pelvis. The 123 with liver metastases have been analyzed, and 39 (32%) of these patients have had a surgical resection of the recurrence. This study reflects the increasingly common trend of finding and resecting hepatic metastases in the setting of primary colorectal cancer. The major clinical concept of surgical resection for metastases is that the metastases are the only site of disease and that removing the metastases will result in a cure. The liver is the most common site for metastases from colorectal cancer; it is involved in over 60% of patients who have metastases. It is thought that metastases travel to the liver through the portal vein because the liver is the first capillary bed for the gastrointestinal venous blood flow. The metastatic cells from the primary would be stopped in this portal sinus area. Interestingly, once the metastases become established, they lose their connections to the portal vein and establish vascular connections to the hepatic artery. Even from a very small size these metastases do not receive blood flow from the portal vein, and this establishes the hepatic artery as the only route for regional chemotherapy. Because patients can only be cured by regional treatment if the disease is confined to the area being treated, when the liver resections are performed, the patients must have their disease confined to the liver. A study of more than 5,000 patients after surgical resection of a primary colorectal cancer, established that 16% of patients developed liver-only metastases. 8 Since approximately 130,000 cases of colorectal cancer are seen each year in the United States, it could be estimated that more than 20,000 patients per year will have liver-only metastases. If 30% of these are resectable, then 6,000 patients a year will have potentially resectable hepatic metastases. This large number of patients is reflected by more and more reports of surgical series of over 1,000 patients receiving resections of hepatic metastases. 4,5 These large studies on liver resections have shown that these operations can be performed with low mortality, lower than 5% and with a 5-year survival of 30%, especially for patients with 1 to 3 lesions. However, even with the most modern techniques and newer systemic chemotherapeutic regimens, the majority of patients will still relapse after liver resection. Furthermore, over half of the patients who fail after hepatic resection fail in the liver. 8-11 Ways to decrease this recurrence rate have been needed to improve this invasive treatment. Copyright 2002, Elsevier Science (USA). All rights reserved.