AIM: To investigate the homing effect of immature dendritic cells (iDC) after injection of iDC into the mouse hepatoma treated by microwave ablation and the possibility of stimulating tumor immunity after thermal ablation. METHODS: The model of hepatoma was established with Hepa 1-6 cells injected into the subcutaneous tissue of C57BL/6J mice. The tumors were treated by microwave ablation under different temperatures, and then fluorescent-labeled iDCs (PKH26-DC) were injected into the ablated tumor tissues. The influences of ablation to homing of PKH26-DC, maturation and excitation ability towards T-cell were observed. RESULTS: There were no homing PKH26-DCs and expression of CCR7 in draining lymph nodes in (65?5)℃ and (90?5)℃ ablation groups after intratumoral injection of iDCs. The number of homing PKH26-DCs was 32?8 in (50?5)℃ ablation group vs 21?6 in un-ablated group, and the expression rate of CCR7 was 100% vs 90%. The number of clusters with immunological synapsis was 8-12 in (50?5)℃ ablation group vs 4-6 in un-ablated group under 100-magnification visual field, and the number of lymphocytes in each cluster was 12-25 vs 3-10. CONCLUSION: Thermal ablation of hepatoma under an appropriate temperature level may promote maturing and homing of iDCs and stimulate immunity of lymphocytes.

Objective To evaluate ultrasound-guided percutaneous ablation for recurrent hepatocellular carcinoma.Methods In this study, 141 patients with recurrent hepatocellular carcinoma (628 lesions) were treated by percutaneous ablation therapies, including microwave, radiofrequency, ethanol injection and hot distilled water ablation.Results The complete ablation rate was 92.0% (578/628) in this group, and was 96.3% ( 105/109 )? 92.9%(119/128)? 91.5% (311/340) and 84.3% (43/51), respectively, for microwave, radiofrequency, ethanol and hot distilled water ablation subgroups.The local recurrence rate was 13.5% ( 78/578 ), and was 11.4% (12/105)? 13.4% (16/119)? 11.9% (37/311) and 30.2% (13/43), respectively, for microwave, radiofrequency, ethanol and hot distilled water ablation subgroups.After a follow-up period of 2-66 months, liver function remained unchanged in 117 patients (81%) after ablation therapies.Patients were followed-up for 2-66 months, the 1, 3 and 5-year survival rate was 75%, 53% and 26%, respectively.Conclusion Ultrasound-guided percutaneous ablation therapies for recurrent hepatocellular carcinoma are safe and effective, while incuring minimal damage to liver function and improving long-term survival.

AIM: To investigate the effect of microwave ablation of liver cancer on the cellular immunity in mice. METHODS: A C57BL/6J mouse model of liver cancer was established by subcutaneous injection of Hepa 1 - 6 cells. The tumors were subjected to microwave ablation under the ablation condition of 45 ℃, 50 ℃, 55 ℃ or 60 ℃ for 180 s. The CD4~+ T cells, CD8~+ T cells and natural killer cells (NK) in peripheral blood were detected by FACS. The cytotoxicity of splenic NK and splenic cytotoxic T lymphocytes (CTL) activated by inactivated Hepa 1-6 cells was assayed by LDH method. RESULTS: The proportions of CD4~+ T cells, CD8~+ T cells and NK cells in peripheral blood in 50 ℃ and 55 ℃ group at 21 d after ablation were significantly increased and that of NK cells in 60 ℃ group was significantly increased. There was no significant difference between those in group 42 d after ablation and control. The cytotoxicities of splenic CTL and NK cells in 50 ℃ and 55 ℃ groups at 21 d or 42 d after ablation were significantly increased, and they were much higher than those in 45 ℃ group at the same time. The cytotoxicities of splenic CTL in 50 ℃ and 55 ℃ groups at 21 d after ablation were much higher than that in 60 ℃ group at the same time. CONCLUSION: Under a certain ablation temperature, microwave ablation of liver cancer promotes the cellular immunity.