63. C-erbB-2 Oncoprotein Expression Correlated with Local Control and Long Term Prognosis in Radiation Therapy for Adenocarcinoma of the Uterine Cervix.

Takashi Nakano, Kuniyuki Oka, Atsuko Abe, Shinroku Morita, and Hirohiko Tsujii

Keywords: C-erbB-2 oncoprotein, radiation therapy, adenocarcinoma, uterine cervix

Background: The correlation between the c-erbB-2 expression on cancer cells and radiation sensitivity or local control has not been evaluated.

Materials and Methods: A total of 47 patients with stage I-III adenocarcinoma of the uterine cervix were investigated for the prognosite significance of c-erbB-2 expression and epidermal growth factor recepter (EGFR) after radiation therapy alone. The c-erbB-2 expression and EGFR were detected by immuno-histochemical staining.

Results: C-erbB-2 oncoprotein was expressed on the surface membrane of cancer cells. Of 47 patients, 18 (38.3%) were positive for c-erbB-2 expression. The positive incidences for stages, I, II and III were 14.2%, 26.7% and 52.0%, respectively, increasing significantly advancing stages. As for the EGFR expression on the cancer cells, 15 patients (31.9%) were EGFR positive. No significant correlation between c-erbB-2 and EGFR expressions was observed. The 10-year survival rates for patients with c-erbB-2 expression was 28.2%, significantly worse than the 58.6% of those without c-erbB-2 expression (p<0.01). This difference was due to local control status rather than distant metastasis. The 10-year survival rate for patients with EGFR expression was somewhat better than that without EGFR expression, although it did not reach a statistical significance (60% vs. 37.8%). Multiple regression analysis indicated that c-erbB-2 oncoprotein expression and tumor volume were independent prognostic indicators.

Conclusion: The c-erbB-2 oncoprotein expression was associated with malignancy of the tumor and was an important predictor for local control and long term prognosis following radiation therapy for adenocarcinoma of the uterine cervix.