Comparison of the efficacy between concurrent chemoradiotherapy with or without adjuvant chemotherapy for stage II nasopharyngeal carcinoma

BACKGROUND: Although common, the use of concurrent chemoradiotherapy with adjuvant chemotherapy for stage II nasopharyngeal carcinoma (NPC) is controversial due to its undefined clinical benefits. We, therefore, conducted a retrospective cohort study to investigate whether adjuvant chemotherapy confers survival gains to stage II NPC patients. METHODS: In this study, we examined whether combining adjuvant chemotherapy (AC) and/or concurrent chemotherapy with radiotherapy (CCRT) improved survival in patients with stage II NPC. Three hundred thirty-five stage II NPC patients were retrospectively analyzed between June 2003 and June 2016 and received CCRT; some patient groups also received AC every 3 weeks for 2 to 3 cycles. RESULTS: The median follow-up duration was 72 months for all patients (range, 26–151 months) and the estimated 5-year locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) rates were 95.1%, 97.8%, 93.5%, and 94.3%. At the last follow-up, there were no statistically significant differences among the CCRT and CCRT+AC groups in 5-year LRRFS (95.2% vs 94.9%, P = .599), DMFS (98.5% vs 92.4%, P = .152), PFS (93.8% vs 90.2%, P = .599), or OS (95.5% vs 93.9%, P = .682) rates. CONCLUSION: The analyses revealed that a combined regimen was not an independent prognostic factor for any survival outcome. However, patients who received CCRT plus AC experienced more acute adverse events than those who received CCRT alone. Thus, the addition of AC to CCRT did not improve survival outcomes, but was associated with higher incidences of acute treatment-associated toxicities than CCRT alone in patients with stage II NPC.