Comparative Effectiveness of Induction Chemotherapy Regimens in Pediatric and Adolescent Locally Advanced Nasopharyngeal Carcinoma: A Retrospective IPTW Analysis.

Induction chemotherapy (IC) is a first-line treatment for locally advanced nasopharyngeal carcinoma (LA-NPC). However, data on the efficacy and safety of different IC regimens in pediatric patients remain scarce, as this group is often excluded from clinical trials. This retrospective study analyzed pediatric NPC patients (age ≤ 21 years) who received IC between 2006 and 2022. To balance confounding factors, inverse probability of treatment weighting (IPTW) was applied. Among 493 included patients, the median follow-up was 69 months. Before adjustment, the taxane-plus-platinum (TP) group showed significantly shorter distant metastasis-free survival (DMFS) than the non-TP group, who received TP plus 5-fluorouracil or capecitabine (TPF/C), platium plus 5-fluorouracil (PF) or gemcitabine plus platium (GP), (p = 0.032). Similar results were observed after IPTW adjustment. And overall survival and progression-free survival did not differ significantly between TP group and non-TP group. Conversely, the non-TP regimen was associated with a higher incidence of any grade toxicities (92.0% vs. 98.4%; p = 0.002). Subgroup analysis revealed that TP-based IC was associated with worse DMFS in patients aged ≤ 14 years, those with EBV-DNA ≤ 4000 copies/mL, and those with N3 stage disease. For pediatric LA-NPC, a non-TP IC regimen was associated with superior DMFS compared to a TP regimen, despite a higher rate of toxicities. The potential disadvantage of TP in younger/high-risk patients is hypothesis-generating and requires validation.