A method for decreasing proliferation of cancer cells comprises the steps ofadministering a sensitizer. Sensitizers caninclude selenium, fish oil, and a combination of selenium and fish oil to acancer cell. The method contemplates that the selenium andfish oil are administered in an amount effective to respectively increase thesensitivity of the cancer cells, and the administration of thecombination of selenium and fish oil are administered in an amount effectiveto synergistically increase the sensitivity of the cancercells more than the selenium or the fish oil alone. The method additionallyexposes cancer cells to temperatures in excess of 37° C.