T.F. Liu and W.C. Xue
Up to now, the three main weapons against cancer have been surgery, radiotherapy and chemotherapy. Although these classical methods of treatment have given fairly good results in general, the results have yet to be improved, especially in late cases. Thus for many years, the search for a more effective means of anti-cancer treatment has been going on world-wide. An ideal drug would of course be one that could directly kill all the cancer cells without harming the normal tissues, and also without causing general toxicity. However, at present a more practical approach is to use drugs that would either enhance the biological effects of radiation or of cytotoxic agents, or strengthen the organism’s immunological defenses. In recent years, several such drugs have been undergoing clinical trials, for example, Misonidazole, RS 2508, OK-432, PSK, etc.