Main Session
Sep 29
PQA 07 - Head and Neck Cancer, Lung Cancer/Thoracic Malignancies, and Nursing and Supportive Care

3541 - Neoadjuvant or Adjuvant Immunotherapy in Nasopharyngeal Carcinoma: Which Strategy Optimizes Survival, Compliance, and Cost-Effectiveness?

03:45pm - 05:00pm ET
Poster Hall - Exhibit Hall A
Screen: 8
POSTER

Presenter(s)

Sai-Lan Liu, - Sun Yat-Sen University Cancer Center, Guang Dong Province, Guangdong

W. P. Guo1, C. Wu1, J. S. Xiao1, D. H. Luo1, Q. Chen1, L. Tang1, H. Q. Mai2, L. Guo1, and S. L. Liu1; 1Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center, Guangzhou, China, 2Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center, Guang, Guangzhou, China

Purpose/Objective(s):

Optimal sequencing and duration of immunotherapy (neoadjuvant [neo-IT] vs adjuvant [adj-IT]) with chemoradiotherapy for locoregionally advanced nasopharyngeal carcinoma (LA-NPC) remain undefined. Without head-to-head trials, clinicians lack guidance on balancing efficacy and treatment burden. This study aims to evaluate the comparative survival outcomes, safety profiles, and cost-effectiveness of neo-IT vs adj-IT strategies to identify the optimal therapeutic timing.

Materials/Methods:

This real-world study and economic evaluation analyzed data from 2019 to 2022, with a median follow-up of 30.6 months in a a major academic oncology center in an endemic region for NPC. Inverse probability weighting (IPW) and propensity score matching (PSM) balanced baseline characteristics. A decision-analytic model evaluated cost-effectiveness from the perspective of the Chinese healthcare system. Primary outcomes included progression-free survival (PFS). Secondary outcomes included overall survival (OS), locoregional recurrence-free survival (LRRFS), and metastasis-free survival (DMFS), acute toxic effects, and incremental cost-effectiveness ratios (ICERs).

Results:

555 patients with diagnosed LA-NPC treated with chemoradiotherapy were included. PD-1 inhibitors administered either neoadjuvantly (neo-IT group; n = 358) or adjuvantly (adj-IT group; n = 197). After weighting, survival outcomes were comparable between strategies. There were no significant differences in 3-year PFS (87.6% vs 88.9%; hazard ratio [HR], 1.1; p = 0.87) or OS (98.7% vs 98.5%; p = 0.96). Incidence of grade 3-4 acute hematologic toxic effects was similar (33.0% vs 34.0%; p > 0.99). However, subgroup analyses indicated that adj-IT reduced metastatic risk in patients with detectable mid- or post-RT plasma Epstein-Barr virus (cfEBV) DNA. Economically, neo-IT was the dominant strategy, with significantly lower mean total costs ($25,707 vs $30,164). For each life-year and quality-adjusted life-year gained, the neo-IT strategy saved $53,026 and $61,037, respectively. The probability of neo-IT being cost-effective was 90.5%.

Conclusion:

Neo-IT yielded survival and safety profiles comparable to adj-IT but demonstrated superior cost-effectiveness, supporting its use as the preferred strategy for the general population. However, adj-IT may offer clinical advantages for high-risk patients with detectable cfEBV DNA at mid-RT or post-RT.