Low hMLH1 expression prior to definitive chemoradiotherapy predicts poor prognosis in esophageal squamous cell carcinoma.

The present study evaluated the pretreatment expression patterns of hMLH1, MDM2, p53, and pRb protein to determine whether these could predict the outcome of definitive concurrent chemoradiotherapy (CCRT) in 51 patients with stage I-IVa esophageal squamous cell carcinoma. High immunoreactivies of hMLH1, MDM2, p53, and pRb were detected in 90.2%, 19.6%, 27.5%, and 66.7% of entire patients, respectively. High hMLH1 expression was found to favor earlier stage, less locoregional failure, and longer cause-specific survival, and all were with significance. However, the expressions of MDM2, p53, and pRb were not found to be clinically significant. Thirty-three patients with high hMLH1 and pRb expression tended to survive longer than four patients with low hMLH1 and pRb expression. We suggest that the expression of hMLH1 is a potential marker of tumor response and survival. Determinations of this protein expression might be useful for selecting esophageal squamous cell carcinoma patients for definitive CCRT.