The purpose of this study is to draw blood from vessels near the liver in patients undergoing liver surgery. This will be performed in both patients with cancer in order to learn more about circulating tumor cells, proteins and DNA mutations in the blood.

The blood in patients with colorectal cancer with liver metastases will be compared to blood taken from patients that do not have cancer that do not have cancer.

Inclusion of patients with benign pathology will allow for the establishment of "normal" values which currently do not exist. We will then study whether tumor mutations can be used to predict recurrence and survival patterns.

Inclusion Criteria:

• All patients with resectable CRLM without extrahepatic metastases confirmed by tissue diagnosis or radiologic exam who are undergoing hepatic resection.
• All patients undergoing hepatic arterial infusion pump placement with or without without hepatic resection.
• Patients may have synchronous or metachronous CRLM
• Patients may have received prior cytotoxic (must be off for at least 2 weeks prior to surgery) or anti-angiogenic therapy (must be off for at least 6 weeks prior to surgery). Specific drugs are listed below.
• 5-FU based chemotherapy - 2 weeks off
• Bevacizumab - 6 weeks off
• Cetuximab or panitumumab - 2 weeks off
• Control patients will include patients consented for pancreaticoduodenectomy for benign or pre-neoplastic lesions. If lesions assumed to be benign turn out to be malignant on final pathology, the blood will be discarded and the patient replaced.
• Patients undergoing a two-stage hepatectomy resection, or who are reevaluated for a second hepatectomy, will be considered for reenrollment to protocol

Exclusion Criteria:

• Evidence of extra-hepatic disease on pre-operative imaging or at operative exploration, excluding the primary colorectal tumor
• Those with known bleeding or clotting diatheses
• Patients diagnosed with chronic inflammatory diseases such as lupus, rheumatoid arthritis, psoriasis, ulcerative colitis, Crohns disease, etc.
• Pre- or intra-operative evidence of portal vein thrombosis or hypertension
• Patients who have taken immune modulating agents in the past 8 weeks including steroids, anti-TNF-α, interferon etc. Patients taking a single dose of Decadron as part of a chemotherapy regimen will not be excluded from the study.
• Patients who take daily anti-inflammatory medications such as COX-2 inhibitors or high dose NSAIDs. Patients taking a daily aspirin or acetaminophen or occasional anti-inflammatory medications will not be excluded from the study.
• If at the discretion of the operating surgeon, blood acquisition would lead to undue morbidity, the patient will be excluded and replaced
• Attending physicians authorized to obtain informed consent may exercise discretion in excluding individuals for appropriate medical or other reasons.