Locoregional immunochemotherapy in primary and metastatic liver disease: meta-analysis and review of literature

BACKGROUND/AIMS: Primary and metastatic liver tumors are the most common malignancies that resist conventional chemotherapy and radiotherapy. Several immunotherapies have been attempted for cancer treatment on the basis of stimulating host immune response to tumors and recent development of combined targeting locoregional immunochemotherapy reported with promising results. However, the efficacy of this therapeutic modality is not yet widely established. METHODOLOGY: We reviewed the medical literature for publications dealing with the value of locoregional immunochemotherapy in patients with primary or metastatic liver tumors. RESULTS: We found that 5 and 7 studies have been controlled and inadequately controlled, respectively. Among 131 patients with primary liver cancer, 40 were treated with combined locoregional immunochemotherapy, and 20 with systemic immunochemotherapy, and 71 with systemic chemotherapy served as two control groups. Complete or partial response was observed in 32 out of 40 (80%) patients who received combined locoregional therapy, and in 10 out of 20 (50%) systemic immunochemotherapy controls (P = 0.03). Survival was three times higher in the patients who received combined locoregional therapy compared with systemic chemotherapy controls (18 vs. 5.6 months). Recurrence of tumor was higher in systemic immunochemotherapy controls (P = 0.003). Among 286 patients with metastatic liver disease, 180 patients were treated with combined locoregional immunochemotherapy and 106 patients with systemic immunochemotherapy. Response (complete or partial) was observed in 65 out of 98 (66.3%) patients who received combined therapy, and in 4 out of 26 (15.4%) controls (P < = 0.001). Survival was two-fold higher in the patients treated with combined therapy (21 vs. 10.5 months). Tumor recurrence was higher in the systemic immunochemotherapy controls (P < = 0.001). CONCLUSIONS: The observational studies indicate a plausible therapeutic rationale for the introduction of locoregional immunotherapy in patients with primary and metastatic liver disease.