[Analysis of the eligibility of elderly colorectal cancer patients for adjuvant chemotherapy combined with polysaccharide K].

We enrolled 62 elderly patients( ≥70 years of age) with colorectal cancer who had undergone surgery and postoperative adjuvant chemotherapy at our department and analyzed the overall surviva(l OS) and disease-free surviva(l DFS) to identify the patients who responded to treatment. Postoperative adjuvant chemotherapy was performed with oral anticancer agents, including doxifluridine( 5'-DFUR), uracil/tegafur( UFT), and UFT/Leucovorin( LV); all patients also received polysaccharide K( PSK), an immunomodulator, in combination with chemotherapy. The 3-year OS and DFS rates for all patients were 83.4% and 78.6%, respectively, with no significant differences in these rates based on the chemotherapeutic agents used. The patients were assigned to low and high groups on the basis of the median cut-off values of each clinical laboratory parameter and the data obtained were subjected to univariate analysis. The results of the univariate analysis suggested that carcinoembryonic antigen (CEA) and cancer antigen 125 (CA125) levels were significant prognostic factors. Further multivariate analysis using Cox regression analysis identified the preoperative CEA level alone as an independent factor. When stratification analysis was performed using a preoperative CEA level of 4.0 ng/mL as the cut-off value, the results indicated that the outcome of patients with a high preoperative CEA level may be 8-fold worse than that of patients with a low preoperative CEA level. For these patients, the use of chemotherapeutic drugs that elicit a more potent antitumor effect should be considered.