Expanding the indications for hepatic resection in patients with colorectal liver metastases.

Abstract

Hepatic resection remains the only chance for cure in patients with colorectal liver metastases. The challenge remains in preoperatively identifying the patient who will benefit from resective therapy. Numerous contraindications to hepatic resection for colorectal liver metastases have been identified, but one consistent and discriminatory factor has been the presence of extrahepatic disease. The significance of disease beyond the liver is based on no 5-year survivors in whom a simultaneous resection of extrahepatic disease and hepatectomy had been performed. 1 The dogma was that the presence of metastatic disease in the liver and other location(s) indicated a disseminated systemic phenomena and was beyond the ability of surgical resection to completely extirpate the disease. Multiple macroscopic sites predicted that microscopic metastases were also present and would eventually become clinically evident and ultimately lead to the demise of the patient. The patient was guaranteed to experience recurrent disease that would preclude cure. This dictum may no longer be correct and has been effectively challenged. In this issue of the Annals of Surgical Oncology , Elias et al. 2 have shown that resecting extrahepatic disease and performing a hepatectomy can provide long-term survival in patients with advanced disease. The authors have shown that not all patients with extrahepatic disease automatically harbor microscopic metastases that prevent a curative hepatic resection. Over a 14-year period 75 patients underwent a complete R0 resection of extrahepatic disease simultaneously with hepatectomy. The overall 5-year survival was 28% as compared with 33% in the 219 patients undergoing hepatic resection without extrahepatic disease at the same institution during the same time period. These results will require confirmation by other liver surgeons. In patients that underwent a R1-2 resection, 5-year survival was 7%. Although a distinctly worse outcome, it is superior to patients that did not undergo a hepatic resection. Forty-three patients were considered unresectable (secondary to number or location of hepatic metastases) at the time of presentation and underwent neoadjuvant systemic chemotherapy (5-fluorouracil/leukovorin, plus oxaliplatin or irinotecan). Every patient had an objective response to preoperative therapy and became eligible for hepatectomy. The survival in this group remained inferior to the group of patients that were initially resectable at presentation (13% vs. 41%), which reflects more aggressive disease. Nevertheless, converting every patient with unresectable disease to resectable is remarkable. This observation suggests that the administration of neoadjuvant systemic chemotherapy should be offered to all patients with colorectal liver metastases and may improve overall survival. Not all of the patients will derive benefit from simultaneous resections. Several significant prognostic factors were identified in multivariate analysis. Patients with more than five metastases and multiple sites of extrahepatic disease had a significantly worse survival. The site of extrahepatic disease, pre- or intraoperative discovery of the extrahepatic disease, and repeat hepatectomy were not significant factors in predicting outcome. This article is a significant step in expanding the indications for hepatic resection. This work has shown that in select patients, the presence of extrahepatic disease is no longer a distinct contraindication to performing hepatic resection. Simultaneous resection of extrahepatic disease and hepatectomy should be considered in patients with 1) less than five hepatic metastases that can be resected with a tumor-free margin and 2) a single site of extrahepatic disease that can be resected with a tumor-free margin. To provide benefit, all patients must undergo an R0 resection.