Expression modes and clinical manifestations of latent membrane protein 1, Ki-67, cyclin-B1, and epidermal growth factor receptor in nonendemic nasopharyngeal carcinoma.

Abstract

We aimed to identify clinical significance of latent membrane protein 1 (LMP1), Ki-67, cyclin-B1, and epidermal growth factor receptor (EGFR), in nonendemic nasopharyngeal carcinoma (NPC). The relation between expression of the markers in 45 NPC specimens and clinicopathological and survival variables was statistically analyzed. LMP1 was present in 33% of the tumors, and its presence was associated with advanced nodal and disease stages. Overexpression was defined as labeling index > or = median value for Ki-67, > or = 15% for cyclin-B1, and > or =50% for EGFR, and it was displayed in 50%, 55%, and 80% of the specimens, respectively. Strong EGFR staining intensity and not overexpression of the 3 markers was the variable with statistically significant impact on treatment outcomes in terms of worse local and locoregional tumor control rates. Our results suggest that the evaluation of EGFR staining intensity in patients with NPC may identify a subgroup of patients with poor prognosis.