Can radiotherapy cure fibrosarcoma and angiosarcoma?

Yes and no. Small tumors can be surgically resected then treated with radiation to "clean up" any malignant cells that may have remained, giving an excellent outcome. Radiation by itself generally cannot cure such tumors by itself, although my experience tells me angiosarcoma responds better than fibrosarcoma.
Yes. Usually radiotherapy is used following surgery in the treatment of sarcomas, but both of these sarcomas may respond to radiotherapy.

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Is it possible for radiotherapy cure angiosarcoma and fibrosarcoma?

First step in. Soft part sarcoma is resection, with wide and clear margins. Radiotherapy cures by eliminating microscopic cells that might remain. Read more...