Supplementary Material for: Clinicopathologic Features And Efficacy Of Induction Chemotherapy In Nasopharyngeal Carcinoma: Real-World Experience

Introduction: Nasopharyngeal carcinoma (NPC) accounts for 0.01% of all carcinomas, and 70% of patients have locally advanced disease with a poor prognosis. The mainstay therapy is chemoradiotherapy (CRT), and concurrent administration of platinum-based agents and irradiation provides high local control rates. However, induction (neoadjuvant) chemotherapy (ICT) prior to chemoradiotherapy is recommended for large tumors with a high tumor burden at category 1 level. For induction chemotherapy, platinum-based doublet or triplet combination regimens are recommended. Selected patients with high tumor burden at the time of diagnosis who did not receive induction chemotherapy before chemoradiotherapy were given adjuvant (consolidation) therapy after chemoradiotherapy. This multi-center study aims to share our experience in treatment of NPC and evaluate the factors associated with survival.
Methods: The study included patients diagnosed with NPC who were followed and treated between 2008 and 2022. 142 patients from 6 centers were evaluated. The factors associated with disease-free survival (DFS) overall survival (OS) were evaluated.
Results: The median age of our patients was 51 years (IQR: 16-81 years), and the male:female ratio was 2.5:1. A majority of patients (71%) had stage 3-4 disease. They had locally advanced disease, and 48 patients (34%) received induction chemotherapy. Twenty patients (14%) received adjuvant therapy. The median follow-up was 41 months (range, 2.7 to 175.1 months). The median DFS in NPC was 92.6 months (range, 71.9 to 113.3 months), with the 40th month DFS of 70.9%. The median OS was 113 months (range, 91 to 135 months), with the 40th month OS of 84.7%. Median DFS was 95.3 months (range, 64.2 to 126.4 months) in patients who received induction chemotherapy before CRT, which was longer than in the CRT-only group (p=0.6). DFS at the 40th month was 75.1% in patients treated with induction chemotherapy compared to 65.1% in the CRT-only group. Median OS was 117 months (range, 92 to 142 months) in patients receiving induction chemotherapy, which was longer than in the CRT-only group (p=0.4). OS at the 40th month was 86.7% in patients receiving ICT, but 83.6% in the CRT-only group.
Conclusions: Both objective response rate (ORR) and survival were longer in patients who radiologically responded to chemoradiotherapy following induction chemotherapy. Non-response to induction chemotherapy is a negative predictive indicator. The role of induction chemotherapy in locally advanced NPC is increasing.

引言：鼻咽癌（Nasopharyngeal carcinoma, NPC）占所有恶性肿瘤的0.01%，其中70%的患者为局部晚期疾病，预后不良。其主要治疗手段为放化疗（chemoradiotherapy, CRT），同步给予铂类药物联合放疗可获得较高的局部控制率。然而，对于肿瘤负荷较高的大体积肿瘤，放化疗前给予诱导（新辅助）化疗（induction (neoadjuvant) chemotherapy, ICT）被列为1类推荐方案。诱导化疗推荐采用铂类双联或三联联合方案。部分诊断时肿瘤负荷较高、未在放化疗前接受诱导化疗的患者，在放化疗后接受了辅助（巩固）治疗。本多中心研究旨在分享我们在鼻咽癌治疗中的临床经验，并评估与生存结局相关的影响因素。

方法：本研究纳入2008年至2022年间确诊为鼻咽癌并接受随访与治疗的患者，共纳入来自6个中心的142例患者进行分析。本研究评估了与无病生存期（disease-free survival, DFS）、总生存期（overall survival, OS）相关的影响因素。

结果：本研究纳入患者的中位年龄为51岁（四分位间距：16~81岁），男女性别比为2.5:1。多数患者（71%）处于3~4期疾病，属于局部晚期。其中48例（34%）患者接受了诱导化疗，20例（14%）接受了辅助治疗。中位随访时间为41个月（范围：2.7~175.1个月）。所有鼻咽癌患者的中位无病生存期为92.6个月（范围：71.9~113.3个月），40个月无病生存率为70.9%；中位总生存期为113个月（范围：91~135个月），40个月总生存率为84.7%。在放化疗前接受诱导化疗的患者中，中位无病生存期为95.3个月（范围：64.2~126.4个月），长于仅接受放化疗组（p=0.6）；诱导化疗组患者的40个月无病生存率为75.1%，仅放化疗组为65.1%。诱导化疗组患者的中位总生存期为117个月（范围：92~142个月），长于仅放化疗组（p=0.4）；诱导化疗组的40个月总生存率为86.7%，仅放化疗组为83.6%。

结论：在接受诱导化疗后行放化疗且影像学应答良好的患者中，客观缓解率（objective response rate, ORR）与生存结局均更优。对诱导化疗无应答是一项负面预测指标。诱导化疗在局部晚期鼻咽癌治疗中的作用日益凸显。