W.C. Xue and T.F. Liu
There is no really effective treatment for moderate and advanced stages of esophageal carcinoma. Although surgery for the earlier cases has been able to give a 5 years survival rate of 28.7%, such operable cases are relatively few. By far the greater majority are already in stage III to IV when first seen in the clinic, and radiotherapy alone in these cases has given a 5 years survival rate of only 8-14%. In order to improve treatment results, a variety of chemotherapeutic agents have been used in combination surgery, but so far no really effective drug has been found.
The drug PSP (polysaccharide-peptide of Coriolus versicolor) has been discovered and produced by Professor Qing-yao Yang of. It is a new anti-cancer and immuno-regulatory drug, similar to PSK (Krestin) but the effective component has been found to be larger than PSK. Experimental data has proved these properties of PSP, and in vitro as well as in vivo studies have all proved that PSP is superior to PSK. Of course, as is the case with all new drugs, the ultimate proof of its value will have to be shown by clinical application.
Data on Krestin suggest that this family of drugs when used in combination with radiotherapy, there might be an increase of the biological effects of radiation. To do a pilot study on such a possibility, the authors have treated 41 moderate to advanced cases of esophageal carcinoma with a combination of PSP and radiotherapy.