Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the United States.1 In spite of an increasing emphasis on screening and prevention of this disease, more than 140,000 new cases will have been diagnosed in 2010, comprising approximately 10% of new cancer diagnoses. Although mortality from this disease has improved over the past two decades, more than 40% of patients with colorectal cancer eventually die of their cancer.1,2 Among those patients with advanced disease, more than half will develop liver metastases, more than any other organ, and many will have disease recognizably confined to this organ. Specifically, approximately 20–40% of patients with metastatic CRC have liver-only metastases at the time of presentation or recurrence, accounting for about 30,000 patients per year in the United States.3,4
While not supported by randomized trials, a preponderance of uncontrolled studies have demonstrated that complete resection in patients with liver metastases is associated with dramatically improved survival compared with patients not undergoing surgical therapy. Advances in imaging technology, surgical techniques, and systemic chemotherapy have brought steady improvements in long-term outcome in patients undergoing resection, with 5-year overall survival exceeding 50%. In addition, other surgically delivered locoregional strategies offer promising directions in improving outcomes in these patients, including ablation, and intra-arterial chemotherapy. Herein, an overview is provided of the important clinical issues relating to the surgical management of patients with colorectal liver metastases.
The extent of evaluation and staging of a patient with hepatic metastases should be determined based on the available treatment options. In patients for whom further treatment is not being considered, either due to comorbid conditions or patient choice, an extensive evaluation for the extent of disease may be unjustified. In patients for whom only noncurative systemic chemotherapy is being considered, an evaluation should establish a baseline to facilitate monitoring of the response to treatment at all sites. In those who are or may become candidates for local therapy directed to the liver, it is important to exclude the presence of extrahepatic disease, particularly in the majority of these patients who are asymptomatic from their liver disease.
When evaluating the patient for extrahepatic disease, computed tomography (CT) is the imaging modality used most frequently. Abdominal CT can detect other intra-abdominal disease, while chest CT is most sensitive for identifying pulmonary metastases, detecting 95% of lesions greater than 1 cm in diameter.5–7 While controversial, chest CT should be strongly considered prior to resection of liver metastases, even in patients with a normal chest x-ray.6 The ability of CT imaging to detect extrahepatic disease within the abdominal cavity or pelvis is lower, with a sensitivity reported between 22 and 41%.8,9 Similarly, magnetic resonance imaging (MRI) can be useful in evaluating evidence of extrahepatic disease.8 In addition, MRI may be useful to characterize indeterminate liver lesions. While most consider a high-quality contrast CT sufficient, some have suggested MRI may be the most ...