Pattern of Cell Death Following Neoadjuvant Therapy for Metastatic Colon Cancer

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.