**7. Immunologic response after HIFU**

T-lymphocytes appear in granulation tissue along the ablation margin in all HIFU-treated neoplasms, with no infiltration in those showing typical signs of coagulation necrosis.

The tumor-infiltrating lymphocytes are found mainly in granulation tissue along with immature fibroblasts, new capillaries, and other inflammatory cells.

This observation suggest that their infiltration occurs after HIFU ablation and that these tumor-infiltrating lymphocytes are new lymphocytes moving into the ablated neoplasms from peripheral blood.

As it has been reported by Hartveit and colleagues, this is a typical findings in all tissues treated with HIFU13.

HIFU treatment may definitively increase the local infiltration of tumor infiltrating lymphocytes in the ablation area, including activated cytotoxic T-Cells and Natural-Killer cells14.
