Repeated transarterial chemoembolization in the treatment of liver metastases of colorectal cancer: prospective study.

PURPOSE: To evaluate local tumor control and survival data after transarterial chemoembolization with different drug combinations in the palliative treatment of liver metastases in patients with colorectal cancer.

MATERIALS AND METHODS: The study was approved by institutional review board, and informed consent was obtained from all patients included in the study. A total of 463 patients (mean age, 62.5 years; range, 34.7-88.1 years) with unresectable liver metastases of colorectal cancer that did not respond to systemic chemotherapy were repeatedly treated with chemoembolization in 4-week intervals. In total, 2441 chemoembolization procedures were performed (mean, 5.3 sessions per patient). Of 463 patients, 67.4% had multiple (five or more) metastases, 8% had one metastasis, 10.4% had two metastases, and 14.3% had three or four metastases. The local chemotherapy protocol consisted of mitomycin C alone (n = 243), mitomycin C with gemcitabine (n = 153), or mitomycin C with irinotecan (n = 67). Embolization was performed with lipiodol and starch microspheres for vessel occlusion. Tumor response was evaluated with magnetic resonance imaging. The change in tumor size was calculated and the response was evaluated according to the Response Evaluation Criteria in Solid Tumors. Survival rates from first diagnosis and from first chemoembolization session were calculated according to the Kaplan-Meier method. Follow-up imaging was performed until patient death.

RESULTS: Evaluation of local tumor control resulted in partial response (68 patients [14.7%]), stable disease (223 patients [48.2%]), and progressive disease (172 patients [37.1%]). The 1-year survival rate after chemoembolization was 62%, and the 2-year survival rate was 28%. Median survival from date of diagnosis of liver metastases was 38 months and from the start of chemoembolization treatment was 14 months. There was no statistically significant difference between the three treatment protocols.

CONCLUSION: Chemoembolization is a minimally invasive therapy option for palliative treatment of liver metastases in patients with colorectal cancer, with similar results among three chemoembolization protocols.