About HITV Therapy

HITV therapy at ICVS Tokyo Clinic, for the treatment of advanced or recurrent cancer Hotel New Otani Shin-Kioicho Building 4F 4-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8578, Japan Clinic Information What's New Contact Us TEL: +81 (0)3 3222 0551 Japanese Chinese
About HITV Therapy
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What is HITV therapy?

What is HITV therapy?

The immune system removes foreign invaders from the body. HITV (human initiated therapeutic vaccine) therapy makes the best use of immune cells called dendritic cells, the commanders of the immune system.

The function of dendritic cells is to recognize (identify) foreign substances called antigens and present them to T lymphocytes. Specific CTLs (cytotoxic T lymphocytes), lymphocyte soldiers which possess antigen information identified by dendritic cells, are subsequently induced in the body and attack and kill cancer cells.

The key aspect in dendritic cell therapy is the way in which dendritic cells identify cancer cells as foreign. If dendritic cells can recognize specific cancer antigens, highly reactive CTLs against these antigens would be induced in the body.

Current dendritic cell therapies normally use surgically removed tissue or synthetic antigens called peptides, but live cancer cells in the patient's body carry the most specific cancer antigen.

Thus, HITV therapy aims to perform antigen recognition within the patient's body by directly injecting dendritic cells isolated from the patient into the tumor and ensuring that dendritic cells can identify the most specific cancer antigen, thereby inducing the most potent CTLs.

Features

Since HITV therapy lets dendritic cells identify antigens (foreign substances) by direct injection into tumors, there are no conditions such as that requiring surgically removed tissue, or the need for a patient's tumor protein to match the antigen peptide.

In other words, any cancers are typically treatable if they are present as a solid tumor in the body.
HITV therapy features a balanced combination of radiation treatment and chemotherapy.

The need for a combination of chemotherapy and radiation treatment

The need for a combination of chemotherapy and radiation treatment

HITV therapy generally targets inoperable recurrent and stage 4 advanced cancers.

Advanced or recurrent cancer often presents as multiple lesions. This means that invisible micrometastatis has occurred throughout the body via the bloodstream as well as visible lesions detected by diagnostic imaging such as PET-CT. In such a case, a treatment plan has to be developed to systemically remove invisible micrometastases together with local control of visible lesions.

In HITV therapy, local control of the lesion is first performed in a combination treatment of radiation and intratumoral injection of dendritic cells. By injecting dendritic cells in the same area as irradiation, the cancer cells in the tumor are eliminated and CTLs (lymphocyte soldiers) are produced. We call this tumor vaccination. If this vaccination is done within the body, the tumor itself can become a manufacturing plant of CTLs (lymphocyte soldiers). Induced CTLs in the tumor constantly circulate through the whole body, thereby eliminating micrometastases at the same time.

However, it is very important to be aware that the ability of CTLs (lymphocyte soldiers) induced in the body by HITV therapy to attack is limited. If micrometastases cannot be removed completely by CTLs alone, the cancer cells will proliferate over time and develop into metastases (visible lesions). So in order to reduce the risk of new lesions appearing as much as possible, we recommend combining the treatment with chemotherapy as a method for systemic control.

Recurrent or advanced cancer is difficult to treat because in addition to visible tumors, micrometastatic spread has occurred throughout the body via the bloodstream. We think that to overcome recurrent or advanced cancer, i.e. to reach a state where no new lesions emerge, we need to understand the characteristics of the different potential treatments and make better use of them.

Among these, it is important to take full advantage of dendritic cells, which are the only cells with learning ability, to let the body's immune system recognize cancer cells as being foreign.

Direct injection of dendritic cells into tumors under CT guidance

Direct injection of dendritic cells into tumors under CT guidance

One of the main features of HITV therapy is its mode of direct delivery of dendritic cells to tumors. Using CT imagery as a guide, the doctor inserts a needle and injects dendritic cells into tumors.

To allow dendritic cells to identify antigens (foreign substances), the needle tip must reach the tumor precisely. At our clinic, treatments are conducted under doctors who possess extensive therapeutic experience, by accurately defining the exact location of the tumor and the needle tip that is introduced into the body, based on real-time CT imaging.

Considerations are also made for the environment of the treatment room, by setting up the same special filters that are installed in the clean room and providing an extremely clean environment for safe treatments to be underway.

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