RESUMEN
PURPOSE: The Mesima-Ex is a kind of biologic response modifier, which is extracted from a mushroom called Phellinus linteus. Mesima-Ex consists of various chemical compounds which include protein bound polysaccharide, mucoprotein, triterpenoid, and quinones. Mesima-Ex exerts its antitumor effects by augmenting host immune response without any toxic side effects. In vitro study, Mesima-Ex seems to potentiates antibody dependent cell mediated cytotoxicity (ADCC) and cell mediated cytotoxicity (CMI) against tumor cells. We initiated this study to verify antitumor effects of Mesima-Ex as an antineoplastic agent. MATERIALS AND METHOD: Gastric cancer patients who underwent curative resection with normal hepatic and renal function were eligible. They were divided into two groups by random number table. One group (N=30: Mesima-Ex group) received postoperative adjuvant chemotherapy with 5-FU (500 mg/m2 weekly), adriamycin (40 mg/m2 every 3 weeks) and Mesima-Ex (6 cap daily per Os). Another group (N=37: control group) received 5-FU and adriamycin only without Mesima-Ex. NK (natural killer cell) activity, ADCC (antibody dependent cell mediated cytotoxicity), CD4 , and CD8 cells were measured and an analysis of disease free survival rate of the two study groups was performed. RESULTS: Sixty seven patients were enrolled in this study. Their median age was 55 years old. NK activity (basal activity: 25%) was enhanced significantly at the 2nd, and 4th months in the Mesima-Ex group (28.9%, 43.4%, p0.05). There were no toxic side effects more than grade III from Mesima-Ex administration. The two year disease free survival rate was higher in the Mesima-Ex group than that of the control group (77% vs 58%, p<0.05). CONCLUSION: Mesima-Ex can be used safely as an immunomodulator with standard chemotherapeutic agents for purpose of adjuvant chemotherapy. Mesima-Ex was effective in augmenting host immune response in vitro. The Mesima-Ex group showed a higher two year disease free survival rate than that of the control group.