第一部分 尼妥珠单抗联合铂类为基础的化疗对比含铂双药化疗在复发/转移性鼻咽癌患者中的疗效及预后分析

目的：姑息性化疗是复发或转移性鼻咽癌（recurrent or metastatic nasopharyngeal carcinoma, R/M-NPC）的主要治疗手段。然而，晚期患者应用化疗药物的疗效尚不满意，仍需新药加入来改善生存。尼妥珠单抗（nimotuzumab, NTZ）是针对表皮生长因子受体的单克隆抗体药物，目前对于NTZ联合化疗（chemotherapy, CT）对比单纯CT，R/M-NPC患者的疗效获益知之甚少。

方法：依托中国医学科学院肿瘤医院电子病例信息平台，查询2004年至2018年间接受CT联合或不联合NTZ治疗的R/M-NPC患者，比较两组患者的治疗依从性，生存率和治疗相关的不良反应。

结果：回顾分析了70例R/M-NPC患者的病例：21例（30％）接受NTZ联合CT（NTZ plus CT，NTZ + CT）治疗，49例（70％）接受CT治疗。CT方案包括吉西他滨联合铂类，紫杉烷联合铂类（taxane plus platinum, TP），以及氟尿嘧啶联合铂类。CT组和NTZ + CT组的中位随访时间分别为62个月（范围为3–133）和59个月（范围为9–117）；中位无进展生存期(progression free survival, PFS)分别为7.5 [95％置信区间（confidence interval, CI）6.552-8.381]个月和8.5（95％CI 6.091-10.976）个月，p = 0.424；中位总生存期（overall survival, OS）分别为25.6（95％CI 18.888–32.379）个月和48.6（95％CI 35.619–61.581）个月，p = 0.017。多因素Cox回归分析显示治疗方案（CT vs. NTZ + CT）为影响OS的独立预后因素（HR，0.5；95％CI  0.255-0.979；p = 0.043）。治疗相关的不良反应方面两组患者之间没有显著的统计学差异。对其中53例接受TP联合或不联合NTZ的患者（53.7％）进行了亚组分析，与以上分析结果相似。

结论：我们的研究表明，NTZ+CT的治疗方案为复发/转移鼻咽癌患者提供了新颖的治疗选择并显著延长患者的总生存期。

关键词：不良反应，化学疗法，远处转移，疗效，鼻咽癌，尼妥珠单抗，复发

第二部分：基于cfDNA全基因组测序检测拷贝数变异探索预测晚期头颈部肿瘤患者免疫治疗疗效生物标志物的研究

研究背景和目的：晚期头颈部肿瘤（head and neck cancer, HNC）是预后较差的癌症类型，患者可选的治疗方式有限且疗效欠佳，近年来多项临床研究提示免疫治疗可改善晚期HNC患者的生存和预后，是富有前景的临床治疗选择。由于肿瘤异质性的影响，不同个体进行免疫治疗的疗效具有差异，因此，临床医生在基线识别免疫治疗潜在的获益人群极其重要。HNC患者因疾病晚期较难获取组织标本，基于细胞游离DNA（cell free DNA, cfDNA）的液体活检技术对多种肿瘤的分子诊断、疗效监测及复发预测都显示出良好结果，但迄今为止，HNC免疫治疗相关的cfDNA研究和应用均较少。本研究旨在基于cfDNA无创活检技术，探索能够预测晚期HNC免疫疗效及预后的生物标志物。

方法：收集26名在中国医学科学院肿瘤医院进行免疫治疗的晚期HNC患者的基线血样和50例健康对照血样，其中15名患者在治疗中动态监测血浆cfDNA。行CT检查评估疗前病情及疗后效果。利用低深度全基因组测序技术(shallow whole genome sequencing, sWGS)来鉴定cfDNA全基因组拷贝数变异（copy number variations, CNV），为了表达整个基因组不稳定性（染色体不稳定性），开发了一种新的计算方式-IS评分（IS score）。主要研究目的是探索生物指标与疗效之间的关联性，包括疾病控制率（disease control rate, DCR）和无进展生存期（progression-free survival, PFS）。

结果：CNV重现性分析显示，本研究的染色体臂改变包括21p、17p、22q、19q、3p的拷贝数缺失，21p、8q的拷贝数扩增，其中17p（包含TP53、NCOR1基因）、22q（包含NF2、EP300基因）拷贝数缺失出现的频率最高。对比基线血浆cfDNA测序结果，免疫治疗后发生疾病进展的患者观察到更明显的基因组不稳定性事件，发生17p/22q缺失（7.4个月vs.17.3个月；P=0.0170）、高IS评分（7.4个月vs. 19.9个月；P=0.0026）的患者PFS较差，疾病进展的患者IS评分显著高于实现疾病控制者（P=0.0089），然而，两组人群的cfDNA浓度无显著差异，IS评分与cfDNA浓度之间无显著相关性（P=0.48）。多因素分析显示，IS评分是影响PFS的独立预后因素（P=0.037）。

结论：sWGS为晚期头颈部肿瘤cfDNA检测提供了一种高通量、低成本、无创的途径，疗前cfDNA全基因组CNV可作为预测接受免疫治疗的晚期HNC患者预后的潜在生物标志物，有助于识别高危患者，指导临床决策。

关键词：头颈部癌症，低深度测序，循环游离DNA，拷贝数变异，免疫治疗

Part I   Efficacy and prognosis of nimotuzumab plus platinum-based chemotherapy versus platinum-based chemotherapy alone in patients with recurrent or metastatic nasopharyngeal carcinoma

Background: Palliative chemotherapy has been the mainstay treatment for recurrent or metastatic nasopharyngeal carcinoma (R/M-NPC). However, the efficacy of chemotherapy drugs in advanced patients is still unsatisfactory, and new drug is still needed to improve survival. Nimotuzumab (NTZ) is a monoclonal antibody drug targeting epidermal growth factor receptor. Now, little is known about the efficacy of NTZ plus chemotherapy (CT) versus CT alone for these R/M-NPC patients.

Methods: The case information platform at Cancer Hospital of Chinese Academy of Medical Sciences was queried for patients diagnosed with NPC who received CT with or without NTZ between 2004 and 2018. Treatment compliance, survival outcomes, and adverse effects were compared among these groups.

Results: Records of 70 patients with R/M-NPC were reviewed: 21 (30%) received NTZ plus CT (NTZ+CT) and 49 (70%) received CT. CT regimens included gemcitabine plus platinum, taxane plus platinum (TP), and fluorouracil plus platinum. Comparing the CT group with NTZ+CT group, the median follow up was 62 months (range = 3–133) versus 59 months (range = 9–117); median progression free survival was 7.5 [95% confidence interval (CI) 6.552–8.381] months versus 8.5 (95% CI 6.091–10.976) months, p = 0.424; median overall survival (OS) was 25.6 (95% CI 18.888–32.379) months versus 48.6 (95% CI 35.619–61.581) months, p = 0.017, respectively. Multivariable analysis established treatment group (CT versus NTZ+CT) as an independent prognostic factor for OS (hazard ratio, 0.5; 95% CI 0.255–0.979; p = 0.043). No significant statistical difference between the two groups with regard to adverse effects. Among them, a subgroup analysis was performed in 53 (75.7%) patients who received TP with or without NTZ, which showed similar results.

Conclusion: Our findings suggested that NTZ+CT provides a novel treatment option and prolongs survival significantly for R/M-NPC.

Keywords:adverse effects, chemotherapy, distant metastasis, efficacy, nasopharyngeal carcinoma, nimotuzumab, recurrence

Part II   Detecting copy number variation based on cfDNA whole-genome sequencing to explore biomarkers for predicting the efficacy of immunotherapy in patients with advanced head and neck cancers

Background:Advanced head and neck cancer (HNC) is a type of malignancy with a poor prognosis. Patients have limited treatment options and poor efficacy. In recent years, a number of clinical studies have shown that immunotherapy can improve the survival and prognosis of patients with advanced HNC, which is a promising clinical treatment option. Due to the impact of tumor heterogeneity, different individuals have different efficacy for immunotherapy, so it is very important to select the potential benefit population of immunotherapy. It is difficult for HNC patients to obtain tissue specimens due to advanced disease. Liquid biopsy based on cell-free DNA (cfDNA) has shown good results in molecular diagnosis, monitoring treatment outcome and predicting recurrence of a variety of tumors. But so far, the research and application of cfDNA for HNC in immunotherapy are few. This study aims to monitor immunotherapy response and predict the prognosis based on non-invasive biopsy of cfDNA in HNC patients.

Methods: Baseline blood samples of 26 advanced HNC patients undergoing immunotherapy at the Cancer Hospital of the Chinese Academy of Medical Sciences and 50 healthy control blood samples were collected. Of these, 15 patients were dynamically monitored for plasma cfDNA during treatment. Computed tomography (CT) scans were carried out to assess the condition before treatment and the effect post-treatment. Shallow whole genome sequencing (sWGS) of cfDNA was used to identify copy number variations (CNV), and a new metric was developed—IS score—to describe the genome instability (chromosomal instability). The primary aim of this study was the association between biomarker with treatment efficacy including disease control rate (DCR) and progression-free survival (PFS) in these patients.

Results: CNV reproducibility analysis showed that chromosomal arm alterations included copy number losses in 21p、17p、22q、19q and 3p, and gains of 21p and 8q. The most frequent CNVs were losses in 17p (harbouring the TP53 and NCOR1 genes) and 22q (harbouring the NF2 and EP300 genes). Compared with the baseline plasma cfDNA sequencing results, patients with progressive disease(PD) after immunotherapy have observed more obvious genomic instability events. The copy number losses in 17p/22q (7.4vs.17.3months; P=0.0170) and the IS-score-high group (7.4 vs. 19.9 months; P=0.0026) had poorer PFS. The median IS-score of patients with PD was significantly higher than those with disease control (P=0.0089), however, there was no significant difference in cfDNA concentration between the two groups. The IS-score was not significantly correlated with the cfDNA concentration (P=0.48). In the multivariable analyses, the IS-score remained an independent prognostic factor for PFS (P=0.037).

Conclusion: sWGS offers a highthroughput, cost-effective and non-invasive way to investigate the cfDNA of patients with HNC. Pre-treatment genome-wide CNA in cfDNA is a potential biomarker predicting the prognosis of advanced HNC patients receiving immunotherapy, help identify high-risk patients, and guide clinical decision-making.

Keywords:head and neck cancer, low-pass whole-genome sequencing, cell-free DNA, copy number variations, immunotherapy