Radioimmunotherapy (RIT) utilizes an antibody labeled with a radionuclide to deliver cytotoxic radiation to a target cell. In cancer therapy, an antibody with specificity for a tumor-associated antigen is used to deliver a lethal dose of radiation to the tumor cells. The ability for the antibody to specifically bind to a tumor-associated antigen increases the dose delivered to the tumor cells while decreasing the dose to normal tissues. By its nature, RIT requires a tumor cell to express an antigen that is unique to the neoplasm or is not accessible in normal cells.

Currently, RIT (e.g. ibritumomab tiuxetan) is used to treat non-Hodgkin's lymphoma in patients whose lymphoma is refractory to conventional chemotherapy and the monoclonal antibody rituximab. Other types of cancer for which RIT has therapeutic potential include prostate cancer , metastatic melanoma , ovarian cancer , neoplastic meningitis , leukemia , high-grade brain glioma , and metastatic colorectal cancer .

References

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