Prognostic value of plasma EBV DNA for nasopharyngeal cancer patients during treatment with intensity-modulated radiation therapy and concurrent chemotherapy

  • Chawalit Lertbutsayanukul Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, 1873 Rama IV Road, Pathumwan, Bangkok, 10330
  • Danita Kannarunimit Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, 1873 Rama IV Road, Pathumwan, Bangkok, 10330
  • Anussara Prayongrat Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, 1873 Rama IV Road, Pathumwan, Bangkok, 10330
  • Chakkapong Chakkabat Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, 1873 Rama IV Road, Pathumwan, Bangkok, 10330
  • Sarin Kitpanit Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, 1873 Rama IV Road, Pathumwan, Bangkok, 10330
  • Pokrath Hansasuta Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok

Abstract

Background: Plasma EBV DNA concentrations at the time of diagnosis (pre-EBV) and post treatment (post-EBV) have significant value for predicting the clinical outcome of nasopharyngeal cancer (NPC) patients. However, the prognostic value of the EBV concentration during radiation therapy (mid-EBV) has not been vigorously studied.

Methods: This was a post hoc analysis of 105 detectable pre-EBV NPC patients from a phase II/III study comparing sequential (SEQ) versus simultaneous integrated boost (SIB) intensity-modulated radiation therapy (IMRT). Plasma EBV DNA concentrations were measured by PCR before commencement of IMRT, at the 5th week of radiation therapy and 3 months after the completion of IMRT. The objective was to identify the prognostic value of mid-EBV to predict overall survival (OS), progression-free survival (PFS) and distant metastasis-free survival (DMFS).

Results: A median pre-EBV was 6880 copies/ml. Mid-EBV and post-EBV were detectable in 14.3% and 6.7% of the patients, respectively. The median follow-up time was 45.3 months. The 3-year OS, PFS and DMFS rates were 86.0% vs. 66.7% (p=0.043), 81.5% vs. 52.5% (p=0.006), 86.1% vs. 76.6% (p=0.150), respectively, for those with undetectable mid-EBV vs persistently detectable mid-EBV. However, in the multivariate analysis, only persistently detectable post-EBV was significantly associated with a worse OS (hazard ratio (HR) = 6.881, 95% confident interval (CI) 1.699-27.867, p=0.007), PFS (HR= 5.117, 95% CI 1.562-16.768, p=0.007) and DMFS (HR= 129.071, 95%CI 19.031-875.364, p<0.001).

Conclusions:  Detectable post-EBV was the most powerful adverse prognostic factor for OS, PFS and DMFS; however, detectable mid-EBV was associated with worse OS, PFS especially Local-PFS (LPFS) and may facilitate adaptive treatment during the radiation treatment period.

Published
2018-05-23
How to Cite
Lertbutsayanukul, C., Kannarunimit, D., Prayongrat, A., Chakkabat, C., Kitpanit, S., & Hansasuta, P. (2018). Prognostic value of plasma EBV DNA for nasopharyngeal cancer patients during treatment with intensity-modulated radiation therapy and concurrent chemotherapy. Radiology and Oncology, 52(2). Retrieved from https://www.radioloncol.com/index.php/ro/article/view/2974
Section
Clinical oncology