Monitoring the efficacy of conservative treatment of nasopharyngeal carcinoma by examining Epstein–Barr virus DNA titers in blood plasma (review)

Abstract
One of the main problems of nasopharyngeal carcinoma treatment is the high incidence regional and distant failures. The method of choice in the first line therapy for the primarily diagnosed nasopharyngeal carcinoma is chemoradiotherapy with poor success rate. The main etiological factor in the occurrence of nasopharyngeal carcinoma is the Epstein–Barr virus, which DNA’s copies could be detected in blood samples in patients with nasopharyngeal carcinoma, which may indicate tumor activity. The indicators of these titers reach different values depending on the stage of the tumor process, the presence of distant metastases, individual patient parameters, and the tumor response to the therapy. Given the high specificity of this biological marker, it is necessary to consider the possibility of its use as a prognostic indicator for assessing the success of the selected method of conservative treatment, as well as assessing the prognosis.