Long-term prognostic effects of plasma epstein-barr virus DNA by minor groove binder-probe real-time quantitative PCR on nasopharyngeal carcinoma patients receiving concurrent chemoradiotherapy.
OBJECTIVE
To evaluate the long-term prognostic impact of plasma Epstein-Barr virus (EBV) DNA concentration measured by real-time quantitative polymerase chain reaction (RTQ-PCR) in nasopharyngeal carcinoma (NPC) patients receiving concurrent chemoradiotherapy (CCRT).


METHODS
Epstein-Barr virus DNA was retrospectively measured from stock plasma of 152 biopsy-proven NPC patients with Stage II-IV (M0) disease with a RTQ-PCR using the minor groove binder-probe. All patients received CCRT with a median follow-up of 78 months. We divided patients into three subgroups: (1) low pretreatment EBV DNA (<1,500 copies/mL) and undetectable posttreatment EBV DNA (pre-L/post-U), (2) high pretreatment EBV DNA (> or =1,500 copies/mL) and undetectable posttreatment EBV DNA (pre-H/post-U), and (3) low or high pretreatment EBV DNA and detectable posttreatment EBV DNA (pre-L or H/post-D) for prognostic analyses.


RESULTS
Epstein-Barr virus DNA (median concentration, 573 copies/mL; interquartile range, 197-3,074) was detected in the pretreatment plasma of 94.1% (143/152) of patients. After treatment, plasma EBV DNA decreased or remained 0 for all patients and was detectable in 31 patients (20.4%) with a median concentration 0 copy/mL (interquartile range, 0-0). The 5-year overall survival rates of the pre-L/post-U, pre-H/post-U, and pre-L or H/post-D subgroups were 87.2%, 71.0%, and 38.7%, respectively (p < 0.0001). The relapse-free survival showed similar results with corresponding rates of 85.6%, 75.9%, and 26.9%, respectively (p < 0.0001). Multivariate Cox analysis confirmed the superior effects of plasma EBV DNA compared to other clinical parameters in prognosis prediction.


CONCLUSIONS
Plasma EBV DNA is the most valuable prognostic factor for NPC. More chemotherapy should be considered for patients with persistently detectable EBV DNA after CCRT.
Lin
Jin-Ching
JC
Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan. jclin@vghtc.gov.tw
Wang
Wen-Yi
WY
Liang
Wen-Miin
WM
Chou
Hsin-Yi
HY
Jan
Jian-Sheng
JS
Jiang
Rong-San
RS
Wang
Ju-Yu
JY
Twu
Chih-Wen
CW
Liang
Kai-Li
KL
Chao
Jeffrey
J
Shen
Wu-Chung
WC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003131:Combined Modality Therapy / Q000379:methods; D004279:DNA, Viral / Q000097:blood*; D018572:Disease-Free Survival; D005260:Female; D004854:Herpesvirus 4, Human / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000097:blood / Q000188:drug therapy / Q000532:radiotherapy / Q000821:virology*; D016133:Polymerase Chain Reaction / Q000379:methods; D011379:Prognosis; D012189:Retrospective Studies
D004279:DNA, Viral