Prognostic Value Of Expression Of EGFR And Nm23 For Locoregionally Advanced Nasopharyngeal Carcinoma

Objective: In many kinds of cancer patients, the usefulness of biomarkers have been widly made in the initial diagnosis, staging work-up, and early detection of recurrence, and many studies have been shown that the expression of biomarkers before therapy may be able to predict the therapeutic effect and prognostic value of many cancers. To further enhance the efficacy of nasopharyngeal carcinoma patients, this study was to investigate the correlation of the expression of EGFR and nm23 and radiation sensitivity and prognosis of patients with advanced stage nasopharyngeal carcinoma (NPC). The identification of prognostic factors that accurately correlate with treatment outcome would help in determining which nasopharyngeal carcinoma (NPC) patients might benefit from more aggressive multimodality treatment combinations, and consequently improve treatment outcomes.Methods: The study population comprised 127 patients with stage III-IVa NPC with sufficient pretreatment tumor biopsy specimens from 2003 to 2004 and clinical data. All patients received intensity-modulated radiotherapy using 6MV X-rays and platinum-based chemotherapy. The expression of EGFR and nm23 was detected by immunohistochemistry(IHC). Survival analysis was performed using Kaplan-Meier method. The correlation between pretreatment expression of EGFR,nm23 and the results of chemoradiotherapy (CRT) with the long-term follow-up of the patients were analysed. Results: The EGFR expression was correlated with primary lesion stage and clinic stage(P=0.001,0.002 ,respectively). There was a statistically significant association between EGFR expression and radiation sensitivity of patients (P=0.023). There was a statistically significant association between nm23 expression and local lymph node stage(P=0.000). The positive EGFR expression had a higher recurrent rate than the negative(P=0.015).The positive nm23 expression had a lower distant metastasis rate than the negative(P=0.021). Negative expression of EGFR had a significantly better 5-year OS and DFS than positive expression(P=0.015, 0.013, respectively). Positive expression of nm23 had a significantly higher 5-year OS and DFS than negative expression(P=0.001, 0.006, respectively).Multivariate analysis indicated that both pretreatment EGFR and nm23 expression were strong independent factors for the overall survival of NPC patients.Conclusion: Our data suggested that EGFR and nm23 can serve as reliable biomarkers for prognosis prediction in locally advanced NPC patients who may benefit from alternate treatment strategy and targeted treatment. High EGFR and low nm23 expression before radiotherapy may be useful for identifying patients requiring more aggressive treatment.