Description:
e14131 Background: To evaluate retrospectively long-term survival of 594 patients with colorectal liver metastases treated with MR-guided laser-induced thermotherapy (LITT) depending on different factors. Methods: 594 patients with liver metastases from colorectal carcinoma treated with MR-guided LITT between 01/99 and 12/10 were included. For survival analysis tumor localization, TNM classification, number of metastases, diameter and volume of metastases and necrosis, lobular spread, number of treatment sessions, performance of adjuvant chemotherapy and transarterial chemoembolisation were considered. The Kaplan-Meier method was used to conduct this survival analysis. Results: Log-rank test showed statistically significant differences between survival curves, multivariate Cox-regression-analysis (p<0.05) showed prognostic factors regarding overall survival like number of metastases pre intervention, adjuvant chemotherapy, diameter of metastases, ratio of volumes of necrosis and metastases, and affected lymph nodes. Median overall survival rate at the time of first LITT was 25 months, 1-year survival: 78%, 2-year survival: 50.1%, 3-year survival: 28%; 4-year survival: 16.4%; 5-year survival: 7.8%. Numbers of metastases pre intervention: 1-2 metastases with a median survival rate of 60 months; 3-4 metastases: 45 months; ≥5 metastases: 42 months. Median survival rate for metastases <20mm in diameter 36 months; 20-30mm 27 months, 30-40mm 24 months and >40mm 21 months. Affected lymph nodes: median survival rate for patients with N0-classification 30 months, N1-classification 24 months; N2/N3/N4-classification 22 months. Conclusions: Multivariate Cox regression model provided the minimal number of significant variables with the maximal prognostic value concerning overall survival for MR-guided LITT, i.e., diameter and number of metastases and primary classification of lymph nodes.