Reduced expression of p63 has prognostic implications for patients with esophageal squamous cell carcinoma

The p63 gene is a member of the p53 family that plays a role in cell differentiation, development and carcinogenesis. The relationship between p63 expression and the prognosis of esophageal squamous cell carcinoma (ESCC) remains unknown. The present study examines the clinical impact of p63 in patients with ESCC. Resected specimens from 180 patients with ESCC were immunostained for p63 and p53. After establishing a cut-off value for p63 expression, we statistically examined its clinical impact and relationship to p53 expression. At a 50% cut-off value for p63 expression, the 5-year overall survival was significantly longer in p63-positive (46.4%) than -negative patients (11.1%, p=0.05). Among the 180 ESCC patients, 171 (95.0%) were p63 immunoreactive and only 9 (5.0%) were negative. The correlation between p63 status and clinicopathological parameters was not significant, although p63-negativity tended to correlate with distant metastasis (p=0.06) and clinical stage (p=0.08). Univariate analysis demonstrated significant correlations between patient survival and tumor diameter, depth of invasion, lymphatic invasion, vascular invasion, lymph node metastasis and distant metastasis. The survival of patients who did not express p63 and p53 was obviously unfavorable (p=0.03). Multivariate analysis revealed that only lymph node metastasis was a critical independent prognostic marker for overall survival (p=0.0015). Expression of p63 was not an independent prognostic factor for overall survival in this study (p=0.69). These data suggest that, although a reduced expression of p63 is infrequent, it has a prognostic impact upon patients with ESCC.