P21 EXPRESSION AS A PREDICTOR FOR FAVORABLE PROGNOSIS IN SQUAMOUS-CELL CARCINOMA OF THE LUNG

Although p21 WAF1/Cip1 expression has been detected immunohistochemica lly in non-small cell lung cancer (NSCLC), the associations between p2 1 expression and clinical characteristics are unknown, To determine th e association between p21 expression and clinical features, p21 expres sion was immunohistochemically analyzed in paraffin-embedded tumor sam ples from 137 patients with curatively resected NSCLC, p21 expression, indicating normal p21 function, was detected in 48 (35.0%) of the 137 patients with curatively resected NSCLC and was detected more frequen tly in patients with stage I or II disease (40.2%) than in those with stage IIIA disease (22.5%; P = 0.0483). There was no difference in the positive rate between squamous cell carcinoma [SCC; 15 of 48 (31.3%)] and adenocarcinoma [30 of 77 (39.0%)]. For SCC, patients with tumors expressing p21 survived longer than did those with tumors negative for p21 expression; however, the corresponding survival time was not sign ificant for adenocarcinoma, On the other hand, p53 expression, detecte d in 58 (42.3%) of these patients, did not act as any predictor for pr ognosis in either SCC or adenocarcinoma. Our findings suggest that the presence of p21 expression is associated with favorable prognosis in SCC and may be useful in obtaining candidates for adjuvant therapies f rom among patients with SCC.