BACKGROUND: Chemoradiotherapy (CRT) is currently performed for patients with esophageal squamous cell carcinoma (SCC). Some reports have revealed that patients who responded well to CRT had favorable outcomes, whereas poor responders conversely showed a worse prognosis. The aim of this study was to identify molecular markers predicting sensitivity to CRT. METHODS: We reviewed 62 patients with T(3-4), N-any, and M-any esophageal SCC treated with definitive CRT. The regimen comprised protracted 5-fluorouracil infusion and a 2-h infusion of cisplatinum combined with radiation therapy (2 Gy/day) at a total radiation dose of 60 Gy. The expressions of epidermal growth factor receptor (EGFR), vascular endothelial growth factor, cyclin D1, and proliferating cell nuclear antigen were investigated immunohistochemically in biopsy specimens obtained before treatment from all 62 patients. The immunoreactivities were compared with responsiveness to CRT, as evaluated by endoscopy. RESULTS: The complete response rate of the primary tumor estimated by endoscopy was 62% (13/21) in patients in the EGFR-positive group. The difference in the CR rate between EGFR-positive and -negative groups was significant (p = 0.037). The immunoreactivities of the other molecular markers did not show a significant correlation with the responsiveness of the primary lesion to CRT. Multiple logistic regression analysis revealed that positive immunostaining for EGFR was significantly correlated with primary CR for CRT in esophageal SCC. CONCLUSION: Among 62 patients with esophageal SCC, differences in the responsiveness of primary lesions to CRT were correlated with EGFR immunoreactivity assessed in the biopsy specimens. These results suggest that EGFR may help to predict the response of primary sites to definitive CRT in esophageal SCC, although the results should be confirmed in a larger, more homogeneous series.
BACKGROUND: Chemoradiotherapy (CRT) is currently performed for patients with esophageal squamous cell carcinoma (SCC). Some reports have revealed that patients who responded well to CRT had favorable outcomes, whereas poor responders conversely showed a worse prognosis. The aim of this study was to identify molecular markers predicting sensitivity to CRT. METHODS: We reviewed 62 patients with T(3-4), N-any, and M-any esophageal SCC treated with definitive CRT. The regimen comprised protracted 5-fluorouracil infusion and a 2-h infusion of cisplatinum combined with radiation therapy (2 Gy/day) at a total radiation dose of 60 Gy. The expressions of epidermal growth factor receptor (EGFR), vascular endothelial growth factor, cyclin D1, and proliferating cell nuclear antigen were investigated immunohistochemically in biopsy specimens obtained before treatment from all 62 patients. The immunoreactivities were compared with responsiveness to CRT, as evaluated by endoscopy. RESULTS: The complete response rate of the primary tumor estimated by endoscopy was 62% (13/21) in patients in the EGFR-positive group. The difference in the CR rate between EGFR-positive and -negative groups was significant (p = 0.037). The immunoreactivities of the other molecular markers did not show a significant correlation with the responsiveness of the primary lesion to CRT. Multiple logistic regression analysis revealed that positive immunostaining for EGFR was significantly correlated with primary CR for CRT in esophageal SCC. CONCLUSION: Among 62 patients with esophageal SCC, differences in the responsiveness of primary lesions to CRT were correlated with EGFR immunoreactivity assessed in the biopsy specimens. These results suggest that EGFR may help to predict the response of primary sites to definitive CRT in esophageal SCC, although the results should be confirmed in a larger, more homogeneous series.