Rationales for combining antiangiogenic treatment and radiotherapy

Abstract

Antiangiogenic treatment is among the most intensively studied fields in oncology. To date, cytotoxic chemotherapy in combination with therapy based on interfering with new vessel formation within the tumor was documented to improve survival in a subset of cancer patients.
Over 50% patients suffering from cancer undergo radiation therapy. In patients receiving definite radiotherapy radioresistance is a great obstacle, since it prevents loco-regional tumor control. In experimental studies the combination of radiation therapy with agents which are directed to proliferating and migrating endothelial cells results in an increased radiosensitivity of the cells to ionizing radiation. Furthermore, paradoxically, antiangiogenic therapy administration may lead to improved oxygenation of cancer cells, which directly contributes to increased cancer radiosensitivity and improved treatment results of cancer patients. However, it should be emphasized that combination of antiangiogenic treatment with radiation therapy may increase the risk of radiation sequels.Pathophisiological rationales for combining of the two mentioned above methods in the therapy of cancer patients as well for introducing such treatment strategy into clinical trials were discussed.