Does three cycles of neoadjuvant chemotherapy prior to concurrent chemoradiotherapy provide benefits for all childhood patients with locoregionally advanced nasopharyngeal carcinoma?

Background: Adding neoadjuvant chemotherapy (NAC) to concurrent chemoradiotherapy (CCRT) is the main strategy in treatment of children and adolescents with locoregionally advanced nasopharyngeal carcinoma (CA-LANPC). Yet, an optimal number of NAC cycles remains unknown. We aimed to optimize the NAC cycle and potentially contribute to clinical decision making for the individual treatment of CA-LANPC.

Patients And Methods: Utilizing an NPC-specific database through an acknowledged big-data information system at our center, we identified 143 CA-LANPC treated with NAC followed by CCRT between September 2007 through April 2018. Recursive partitioning analysis (RPA) was performed to categorize the patients and predict disease-free survival (DFS). The clinical benefits of NAC cycles (two cycles vs three cycles) were assessed in each risk group.

Results: Independent factors derived from multivariable analysis to predict DFS were T stage (T1-3 vs T4) and plasma Epstein-Barr virus (EBV) DNA (< 4000 vs ≥ 4000 copies/mL) for risk stratification. Consequently, 87 (61%) participants were classified as low-risk group (T1-3 with low or high EBV DNA, and T4 with low EBV DNA) and the other 56 patients (39%) were classified as a high-risk group (T4 with high EBV DNA) through RPA, and corresponding 5-year DFS rates of 91.9% and 71.2%, respectively (p = 0.001). Among the high-risk group, patients receiving three cycles of NAC had statistically significant improvement in 5-year DFS over those who received two cycles of NAC (86.7% vs 59.1%; p = 0.020), while the survival benefit of three cycles NAC for low-risk groups were not observed (94.7% vs 89.7%; p = 0.652).

Conclusions: We found three cycles of NAC with CCRT was a positive prognostic indicator for improved DFS for the high-risk group among CA-LANPC. However, whether low-risk patients could benefit from three cycles NAC needs further study.