Weekly versus triweekly cisplatin-based concurrent chemoradiotherapy for nasopharyngeal carcinoma: a systematic review and pooled analysis

Background: Weekly and triweekly cisplatin-based concurrent chemoradiotherapy (CCRT) have been used in the treatment of nasopharyngeal carcinoma (NPC). Objective: This study aimed to compare the benefits and risks between the two treatments. Methods: We systematically searched electronic databases for prospective and retrospective clinical studies of NPC patients who received weekly compared with triweekly cisplatin-based CCRT. The primary endpoints comprised overall, failure-free, distant metastasis-free, and locoregional recurrence-free survivals (OS, FFS, DMFS, and LRFS). Secondary endpoints were toxicities. Results: Six studies were included in the systematic review, of which four with 1515 NPC patients were eligible for further pooled analysis. There were no significant differences between weekly and triweekly groups in terms of 5-year OS (odds ratio [OR] 0.95, 95% confidence interval [CI] 0.51-1.79), FFS (OR 1.09, 95% CI 0.67-1.76), DMFS (OR 1.25, 95% CI 0.54-2.92), and LRFS (OR 0.83, 95% CI 0.55-1.25). For grade ≥ 3 toxicities, the weekly group had higher risks of anemia (risk ratio [RR] 2.96, 95% CI 1.12-7.81) and thrombocytopenia (RR 2.75, 95% CI 1.54-4.90), but a lower incidence of vomiting (RR 0.34, 95% CI 0.18-0.63) versus the triweekly group. Conclusion and Relevance: Both weekly and triweekly schedules could be recommended to NPC patients during CCRT. Additionally, hematologic adverse events in weekly strategy and non-hematologic adverse events in triweekly strategy are of higher concern.