Immunohistochemical Study on bcl-2, c-myc, EGFR as Predictable Factor for Radiosensitivity in Early Glottic Cancer / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: The radiotherapy or surgery is the main treatment modality for early glottic cancer. The advantage of radiotherapy is the preservation of good voice quality after treatment but the main problem is increased complications in the salvage surgery when local control fails. So, it is important to predict the success of radiotherapy. The purpose of this study is to find predictable factors of the radiosensitivity in the early glottic cancer. MATERIALS AND METHOD: Immunohistochemical staining was performed on the paraffin sections of the biopsy specimens of 57 patients with early glottic cancer who had undertaken radiotherapy treatments in Chonnam National University Hospital from January 1988 to October 1998. Primary antibodies were the anti-bcl-2 monoclonal antibody, the anti-c-myc monoclonal antibody, and the anti-EGFR monoclonal antibodies. The relation between the local control outcome after radiotherapy and the result of immunostaining was analyzed by the chi-square and the Fisher's exact test. RESULTS: Positive expression of bcl-2 was 21.1% in the local controlled group and 12.3% in the uncontrolled group. There was no statistical significance between two groups. The expression rate of c-myc was statistically higher in the controlled group (36.8%) than in the uncontrolled group (7.0%) (p=0.025). Expression of EGFR was 57.9% in the controlled group and 22.5% in the uncontolled group. However, there was no statistical significance between two groups. CONCLUSION: The relation between the positive c-myc expression and the radiosensitivity suggests that c-myc might be a predictable factor of the radiosensitivity in early glottic cancer.