Systemic chemotherapy for metastatic colon cancer is often used in the neoadjuvant setting for patients undergoing liver resection. This treatment is given either to keep the tumor at bay or reduce its size before the time of resection. While many metastatic tumors might appear to respond well and even radiographically disappear following neoadjuvant therapy, it is unclear whether grossly or radiographically negative areas of previous disease are microscopically free of tumor cells. As such, when possible, resection boarders typically follow 1 cm margins from the tumor size prior to neoadjuvant therapy. These margins might be necessary to encompass all histologically present disease or they might be unnecessarily large, serving only to increase the mortality and morbidity of the operation. This study begins to address this question by a histological examination of the pattern of cell death in areas of metastases removed after neoadjuvant therapy. Furthermore, clinical cases in which neoadjuvant therapy allowed for resection of previously unresectable cancer will be examined to determine whether there is an increased rate of recurrence despite "negative" resection boundaries in these cases.

Inclusion Criteria:

• Patients must be ≥ 18 years old.
• Patients must have colon cancer metastases to the liver.
• Patients must be candidates and be scheduled for liver resection.
• Patients must have received and have had a response to neoadjuvant therapy prior to liver resection.
• Patients must have signed Institutional Review Board (IRB) approved written consent form prior to registering in the study.

Exclusion Criteria:

• Patients who are < 18 years old.
• Patients who do not have colon cancer metastases to the liver.
• Patients who are not surgical candidates.
• Patients who do not schedule or who cancel a liver resection.
• Patients who have not received neoadjuvant therapy.
• Patients who have received neoadjuvant therapy but who have had no response or who have had tumor progression.

Patients with colon cancer metastases to the liver