Abstract 5112
Background
No previous study reported the treatment outcome of stage III nasopharyngeal carcinoma (NPC) patients. The aim of this study is to investigate the long-term clinical outcome of stage III NPC patients and do risk grouping by plasma EBV DNA assay for future therapy improvement.
Methods
A total of 356 previously untreated, pathologically-proven NPC patients with stage III disease and available pretreatment plasma EBV DNA data were enrolled in this retrospective study. Initial definitive treatment consisted of concurrent chemoradiotherapy or induction chemotherapy plus radiotherapy. Eighty-four of 356 (23.6%) patients also received post-RT adjuvant chemotherapy. Patients with pretreatment EBV DNA > 1000 copies/mL were defined as a high-risk subgroup (n = 106) and the remaining patients as a low-risk subgroup (n = 250).
Results
After a median follow-up of 90 months, there were 66 recurrences (18.5%) and 57 deaths (16.0%). The 5-year overall survival (OS), progression-free survival (PFS), distant metastasis failure-free survival (DMFFS), and locoregional failure-free survival (LRFFS) for all 356 patients were 88.4%, 83.9%, 90.5%, and 90.5%, respectively. Thirty-five of 105 (33.0%) high-risk patients developed tumor relapse later, whereas only 12.4% (31/250) low-risk patients had tumor relapse (P
Conclusions
Long-term treatment results for Stage III NPC patients were good. Risk grouping identified a subgroup of patients with high pretreatment EBV DNA had a significantly higher relapse rates and worse survivals. Future trial should strengthen treatment intensity for these high-risk patients.
Clinical trial identification
Legal entity responsible for the study
Taichung Veterans General Hospital
Funding
Taichung Veterans General Hospital
Disclosure
All authors have declared no conflicts of interest.