A system for loading a surgical buttress with a radioactive material includes a surgical buttress, a radioactive material delivery instrument, and a radioactive material. The surgical buttress includes a body portion defining a first width when in a pre-loaded configuration and a second width when in a loaded configuration. The radioactive material delivery instrument includes an elongate body extending from a handle assembly. The elongate body defines a lumen therethrough and has an open distal end. The radioactive material is disposed within the lumen of the elongate body of the radioactive material delivery instrument.
