a low - energy , nonabsorbable radioactive seed patch method and apparatus for use in conjunction with surgical procedures for prevention of reoccurrence of carcinoma and other type tumors . the patch is a nonabsorbable , plastic mesh with iodine - 125 seeds threaded therein according to a predetermined pattern . the mesh with seeds threaded therein is then embedded in a nonabsorbable silicone forming the completed patch . the patch is permanently implanted over the area of potential residual cancer following surgery .