Elizabeth J. Sutton MD, Presenter: Nothing to Disclose

Richard Kinh Gian Do MD, PhD, Abstract Co-Author: Nothing to Disclose

Kristen Lynne Zakian, Abstract Co-Author: Nothing to Disclose

Debra Goldman BS, Abstract Co-Author: Nothing to Disclose

Nancy Kemeny MD, Abstract Co-Author: Nothing to Disclose

Michael D'Angelica MD, Abstract Co-Author: Nothing to Disclose

Among different therapies for colorectal liver metastases (CLM), hepatic arterial infusion (HAI) can deliver high dose chemotherapy with high response rates. However, there is limited ability to predict treatment response before surgery and this would be of obvious value. The purpose of this study was to evaluate CT imaging and clinical predictors of CLM response to combination HAI plus systemic chemotherapy.

A retrospective review of patients with initially unresectable CLM enrolled in an institutional review board approved prospective trial for HAI pump therapy was performed. 54 patients (mean age 55.6, range 33-76; 22 females and 32 males) were included, 51 of whom had available pre and post-treatment contrast enhanced CT scan available for review. Percentage best response (BR) was evaluated according to Response Evaluation Criteria In Solid Tumors (RECIST) during the trial. For each target CLM identified by RECIST, size and mean Hounsfield Unit (HU) attenuation were measured on pre-treatment portal venous phase CT. Clinical parameters including prior systemic chemotherapy and eligibility for post-treatment surgical resection of CLM were documented. Spearman’s rho and Wilcoxon’s Rank Sum test were used for statistical analysis.

Before treatment, HU attenuation of CLM was higher in patients who eventually underwent surgical resection (p=0.02), positively correlated with BR (rho=0.33; p=0.02) and negatively correlated with size of CLM (rho=-0.32, p=0.02). No significant correlation was found between pre-treatment size of CLM and BR (rho= -0.09; p>0.05). Size of CLM and HU were not significantly different between those who had prior systemic chemotherapy alone and those who did not (p>0.05). No significant difference in pre treatment size of CLM was found between patients who eventually underwent surgical resection and those who remained unresectable (p>0.05).

Increased HU attenuation of colorectal liver metastases on pre-treatment contrast enhanced CT correlates with volumetric response and eventual surgical resectability following treatment with combination HAI plus systemic chemotherapy.

Pretreatment prediction of response to combination HAI and systemic chemotherapy by CT imaging may be helpful in directing targeted care of CLM.

Sutton, E, Do, R, Zakian, K, Goldman, D, Kemeny, N, D'Angelica, M, CT Prediction of Response for Colorectal Liver Metastases to Combination Hepatic Arterial Infusion Plus Systemic Chemotherapy.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13044370.html