 In the preclinical study, we examined tumor specimens for TS and TP expression obtained from 171 Chinese NSCLC patients who were operated without any preoperative chemotherapy or radiation at our institute. We categorized Grades 0 and 1 as negative, Grades 2 and 3 as positive for both enzymes. As for TS staining, 14.6 n 25 were classified as Grade 0, 28.7 n 49 as Grade 1, 32.7 n 56 as Grade 2 and 24.0 n 41 as Grade 3. And for TP staining, 12.3 n 21 were classified as Grade 0, 17.0 n 29 as Grade 1, 13.5 n 23 as Grade 2 and 57.3 n 98 as Grade 3. Although the anti-tumor activity of capecitabine has not been well evaluated in NSCLC, the relatively high expression of TP 70.8 and low expression TS 43.3 in NSCLC provided a rationale for the use of capecitabine in patients with this tumor. 