December 24, 2008 — Chemoembolization is a minimally invasive therapy option for palliative treatment of liver metastases in patients with colorectal cancer, according to the results of a study reported in the January 2009 issue of Radiology.
“In addition to systemic chemotherapy, current therapies of unresectable liver lesions include hepatic arterial infusion of chemotherapeutic drugs, transarterial chemoembolization, radiofrequency ablation, cryotherapy, laser-induced thermotherapy (LITT), and yttrium-90 radioembolization,” write Thomas J. Vogl, MD, from the University Hospital Frankfurt, Johann Wolfgang Goethe-University in Frankfurt am Main, Germany. “Chemoembolization is defined as a selective administration of chemotherapy usually combined with embolization of the vascular supply to the tumor. This treatment results in selective ischemic and chemotherapeutic effects on liver metastases.”
The goal of this study was to evaluate local tumor control and survival associated with transarterial chemoembolization using different drug combinations for palliative treatment of liver metastases in patients with colorectal cancer.
The study sample consisted of 463 patients with unresectable liver metastases from colorectal cancer that had not responded to systemic chemotherapy. Mean age was 62.5 years (range, 34.7 – 88.1 years); 67.4% had at least 5 metastases, 14.3% had 3 or 4 metastases, 10.4% had 2 metastases, and 8% had 1 metastasis.
At 4-week intervals, patients were repeatedly treated with chemoembolization, for a total of 2441 chemoembolization procedures (mean, 5.3 sessions per patient) with use of lipiodol and starch microspheres for vessel occlusion. The local chemotherapy protocol consisted of mitomycin C alone (n = 243), mitomycin C with gemcitabine (n = 153), or mitomycin C with irinotecan (n = 67).
Magnetic resonance imaging was used to assess tumor response, and the Response Evaluation Criteria in Solid Tumors were used to calculate change in tumor size and to determine response. The Kaplan-Meier method was used to calculate survival rates from first diagnosis and from first chemoembolization session, and follow-up imaging continued until patient death.
Of the 463 patients, 68 patients (14.7%) had partial response, 223 patients (48.2%) had stable disease, and 172 patients (37.1%) had progressive disease. After chemoembolization, 1-year survival was 62%, and 2-year survival was 28%. Median survival was 38 months from date of diagnosis of liver metastases and 14 months from the start of chemoembolization. Outcomes with the 3 treatment protocols did not differ statistically significantly.
Limitations of this study include nonrandomized study design and limited differences in the symptomatic and palliative indications for chemoembolization.
“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,” the study authors write. “Repeated studies have therefore shown that it might be possible to prolong survival in the treatment of metastatic colorectal cancer in the liver by means of regional chemotherapy.”
The study authors have disclosed no relevant financial relationships.