贾户亮 钦伦秀
肝细胞癌(hepatocellular carcinoma,HCC)是我国最常见的恶性肿瘤之一,发病率在男性恶性肿瘤中排第5位,女性排第9位;肿瘤死亡原因在男性中排第2位,女性中排第6位,每年中国肝癌新发病例数和死亡人数均超过全球的一半[1]。经过数十年的努力,HCC临床治疗取得明显进展,根治术后5年生存率可达40%~60%,但HCC术后转移复发率较高,已成为进一步提高生存、改善预后的主要障碍(5年复发率达60%,即使小肝癌也达40%)[2]。HCC术后复发的高峰时间在术后1~2年,以肝内复发最常见。根据复发时间,HCC术后复发可分为早期复发(术后2年内)和远期复发(术后2年后)[3],两者的复发原因和危险因素有所不同[4]。早期复发的来源多为肝内播散,是伴血管侵犯的进展期HCC术后复发的主要原因,多为多发病灶;远期复发多为非同期多中心癌变,即在肝硬化的基础上出现新的癌灶。对HCC术后转移复发风险进行精准评估、建立预测预防体系,对转移复发高危人群进行个体化术后防治,进而改善预后,已成为目前肝癌防治工作的关键。
影响HCC术后复发和预后的因素很多,主要包括肿瘤临床病理特征、分子生物学特性、肝病背景以及肿瘤微环境和宿主免疫状态等。
肿瘤临床病理特征,如肿瘤大小、数目、分化程度、血管侵犯以及临床分期等均是肿瘤转移复发的重要影响因素[5],而肿瘤临床病理特征一定程度上是肿瘤生物学特性的反映。肝癌临床病理特征主要影响肝癌术后的早期复发。肿瘤生物学特性包括DNA倍体、增殖指数、癌基因和抑癌基因表达、特别是侵袭转移相关基因的表达等,其对肝癌复发及预后的影响已有许多文献报道证实。
与其他肿瘤不同,肝癌的治疗和预后除了肿瘤本身的情况外,肝脏基础疾病和肝功能状况也是重要的影响因素,包括肝炎感染状态、病毒载量、血清HBeAg状态、肝硬化程度和肝功能储备等都已被证实为肝癌复发的独立危险因素[3-4]。抗病毒治疗可降低慢性乙型肝炎患者肝癌发生率[6],高病毒载量是影响患者术后生存时间的独立因素,是肝癌术后复发的独立危险因素[7]。
肿瘤发生发展是癌细胞与局部微环境及宿主间相互作用的复杂过程。研究表明,肿瘤微环境在机体内在或外在因素的影响下呈现动态改变,在肿瘤增殖、转移以及治疗抵抗中都发挥重要的作用,各种成分之间的相互作用会对肿瘤细胞产生复杂的影响。目前关注较多的是炎症免疫反应状态[8]。
根据HCC术后复发的影响因素对其复发进行准确预测是实施精准干预的前提和基础。
不同分期HCC患者复发转移的风险及预后显著不同。目前有多种肝癌临床分期系统。有文献报道在3 182例HCC患者中比较11种分期系统的分层准确性和预后评估的准确性,发现CLIP分期系统具有最佳分期效果,且不受肝病背景(HBV或HCV相关)、是否接受根治性治疗的影响[9]。其主要原因为CLIP分期系统除了对肿瘤因素进行准确分层和评估外,对合并的肝病背景也进行了准确评估。
过去20年我们进行了一系列研究,有以下一些新的发现:⑴染色体8p缺失:通过比较基因组杂交(CGH)发现染色体8p缺失与HCC转移密切相关[10]。并进一步发现8p11.2和8p23.3两个区段的缺失更重要[11]。检测外周血染色体8p缺失(液体活检)可预测HCC转移复发及预后[12]。即使在早期HCC患者(TNM I期),染色体8p缺失也是影响其预后的独立危险因素[13]。⑵骨桥蛋白(osteopontin,OPN):OPN 是一种重要的分泌型糖蛋白,参与调节细胞黏附、运动、增殖和凋亡等多种生理活动或病理过程。已有多项研究提示该蛋白与肿瘤侵袭转移及预后密切相关。我们研究证实OPN是重要的促进HCC转移基因[14]。HCC患者外周血OPN水平是影响患者预后的独立危险因素,血浆OPN水平高者术后无瘤生存率显著降低[15-16]。此外,还发现在OPN高表达的HCC组织中,如果同时伴有肿瘤组织凝血酶水平高表达,则术后复发率显著增高,且只有在OPN高表达的HCC患者,其肿瘤组织凝血酶表达水平与患者总生存期和无瘤生存期显著相关[17]。(3)多基因分子预测模型:我们比较伴或不伴转移的HCC组织基因表达谱的差异,发现两者基因表达差异明显(153个差异基因,P<0.001),提示高转移倾向HCC与低转移倾向HCC具有完全不同的基因表达谱,为HCC转移早期预测、诊断和防治奠定了理论基础[13]。基于这些差异基因,在国际上首次建立了肝癌转移预测模型,并进一步对其进行小样本验证,证实其预测准确率可达90%[13]。随后进一步在分别来自两个独立临床中心的队列进行大样本验证,证实HCC转移预测的准确率可达76%,这是经过临床大样本验证的全世界第二个癌转移预测模型[18]。基于这一模型,我们进一步优化出“六基因预测试剂盒”,目前已获得转化生产。
我们比较有无转移HCC患者癌周肝组织基因表达谱,发现合并转移的HCC癌周肝组织中存在促炎细胞因子(Th1)明显下调,而抗炎细胞因子(Th2)明显上调。这种独特的Th1/Th2表达改变与失衡提示癌周微环境的炎症免疫状态在HCC转移中起重要作用。我们建立了“17个免疫因子标签”,预测转移和生存的准确率达92%[8,19],并从蛋白水平进一步证实癌周肝组织IL-2和IL-15水平与HCC转移复发及预后密切相关[20]。
1974年Sorrells首次提出“液体活检”(liquid biopsy)的概念,是对体液中细胞、遗传物质或分子标志物异常进行捕获检测分析。液体活检具有创伤小、可多次动态实时监测肿瘤病情变化、便利和相对安全等优势。液体活检包括所有体液(如血液、尿液、唾液、消化道液体等),但血液的液体活检进展最为迅速。其主要包括循环肿瘤细胞(circulating tumor cells,CTCs)、循环肿瘤 DNA(ctDNA)和外泌体(exosome)检测等三大领域,成为肿瘤研究的热点领域[21]。
循环肿瘤DNA(ctDNA)是由肿瘤细胞释放入血,读取分析ctDNA携带的信息(突变、表观遗传修饰及完整性),用于筛查、预后和进展判断,寻找并制定干预策略[22]。通过检测HCC患者血浆甲胎蛋白RNA,早期预测和诊断HCC患者术后转移复发是液体活检在肝癌领域应用的最早报道[23]。2006年我们发现在HCC外周血DNA中检测染色体8p杂合性缺失可预测HCC转移复发风险及预后[12]。
CTCs在肿瘤极早期即可被发现,原发性肿瘤在常规影像学检出之前,外周血中就可能检测到CTCs[24-25]。肿瘤患者CTC计数可作为评估其病情及预后的重要指标,是影响肿瘤患者预后的独立危险因素。除CTC计数外,近年更多关注CTC表型的重要意义,研究发现具有干细胞表型或间质表型CTCs是术后近期复发及预后差的独立危险因素[26-27]。
外泌体是由多种活细胞分泌的具有磷脂双分子膜结构的纳米级囊泡小体,广泛分布于血清、唾液、尿液、腹水、羊水等体液中,外泌体与CTCs和循环游离核酸相比,在体液中具有很高的稳定性,可长期保存。其内含有蛋白质、核酸甚至病毒等多种组成成分。不同组织来源的外泌体在组成和功能方面存在差异,这种差异受到细胞外基质和微环境的动态调控。外泌体能够参与细胞间的物质交换和信息交流,在多种生理和病理过程中发挥重要作用。肿瘤来源或肿瘤相关的外泌体是调控肿瘤发生发展的重要机制,对肿瘤外泌体进行分析和检测可辅助肿瘤早期诊断、疗效评价和预后分析[28-30]。外泌体及其修饰加工产物还可作为基因或药物的有效载体用于肿瘤治疗,为肿瘤临床诊断和治疗带来新的契机。
针对HCC术后复发,临床尝试应用多种辅助治疗干预措施,包括肝动脉化疗栓塞(transcatheter arterial chemoembolization,TACE)、靶向治疗、抗病毒治疗、全身化疗、放疗、免疫与生物治疗等,然而目前只有少数辅助治疗方法经临床随机对照试验(RCT)证明有效[31]。
术前TACE辅助治疗经临床随机对照试验证实并不能减少HCC术后复发[32-33],反而可能对肝功能造成损害,增加肿瘤肝外转移风险。
对于术后TACE辅助治疗价值目前尚争议。有临床RCT研究证实肝癌根治术后行131ⅠTACE辅助治疗可显著降低术后复发,改善预后[34],并延长患者术后5年无瘤生存期和总生存期[35]。然而也有RCT发现术后TACE辅助治疗不仅无法降低术后复发[36],反而可能增加肝内复发和肝外转移风险[37]。由于HCC患者多数合并肝脏基础疾病,反复多次TACE辅助治疗可引起肝损伤,影响患者预后[38]。对于术后TACE辅助治疗作用的临床试验出现不同的结果,其可能的原因之一在于入组病例的选择标准不同。在不同的研究中对于“肝癌根治性切除”的定义有所差别,手术适应证也有所差别。对于复发转移的低危患者,TACE起不到辅助治疗作用,反而可能带来肝功能损伤的副作用。而对于高危患者,预防性TACE治疗的意义可能在于对肝内存在的微小肿瘤病灶发挥作用,进一步清除肝内可能残存的肝癌细胞,降低复发高峰期的复发率[39-40]。目前临床对于合并高复发风险(肿瘤大或多发、伴血管侵犯、可能合并肝内播散等)因素的HCC患者推荐术后接受 TACE 辅助治疗[3,41-42]。
此外,分子标志物可帮助筛选可能受益的患者。有文献报道RPB5介导蛋白(RMP)在HCC肿瘤组织高表达的患者可从术后TACE辅助治疗中获益[43]。另外,研究发现谷氨酰胺合成酶也可作为HCC术后辅助TACE 效果预测标志物[44]。
目前索拉非尼仍是唯一具有HCC适应证的一线靶向治疗药物[45-46]。索拉非尼可用于进展期HCC,延长患者总生存期。而对于HCC根治术后索拉非尼辅助治疗的作用仍需进一步研究。虽有小样本初步临床试验报道术后索拉非尼辅助治疗可以降低复发率,显著延长无瘤生存期[47]。然而有大样本临床随机对照研究(STORM)发现HCC根治术后索拉非尼辅助治疗与对照组在无瘤生存期、总生存期和至复发时间方面均无显著差别[48]。该临床试验阴性结果的可能原因为入组病例选择标准,应强调选择高复发风险HCC患者进行靶向辅助治疗。
已有多项研究证实乙型肝炎相关HCC患者高病毒载量及HBeAg阳性是术后复发的高危因素[49-50]。多项RCT证实术后抗病毒治疗可为HCC患者带来显著的生存获益,降低复发[51-52]。在随机对照试验中,抗病毒治疗显著降低肝癌复发和HCC相关死亡,多因素Cox回归分析中危险比(HR)分别为0.48(95%CI:0.32~0.70)和 0.26(95%CI:0.14~0.50)[53]。此外,回顾性队列研究和荟萃分析也均显示对术后辅助应用核苷类抗病毒药物治疗可以提高生存,降低复发率[53-55]。
基于已有研究结果,大多数HCC患者术后全身化疗辅助治疗的效果不佳。目前尚无大规模随机对照临床试验证实HCC根治术后辅助化疗的作用。大多数肝癌对化疗不敏感,而且长期化疗可使肝硬化患者肝功能进一步恶化,导致肝功能不全和免疫抑制等副作用,影响患者长期生存[56]。
干扰素术后辅助治疗的作用已有较多研究结果证实。干扰素是一种具有广泛生物学活性的免疫细胞因子,可通过免疫调节、抗病毒、抑制肿瘤血管形成、增殖和诱导细胞凋亡等机制发挥其治疗作用[57]。已有多项RCT结果证实,术后干扰素辅助治疗可降低乙型肝炎相关 HCC[58-60]和丙型肝炎相关 HCC[61-62]的术后复发,改善患者预后和生存。有研究报道TACE联合干扰素治疗乙型肝炎相关HCC,患者的总生存率和复发率均明显优于单独TACE治疗[63]。进一步研究干扰素作用机制,发现肝癌组织miR-26a低表达者预后差,但这些患者对干扰素治疗较敏感,术后干扰素辅助治疗可显著改善预后。miR-26a可预测干扰素治疗效果和筛选患者[64]。
免疫治疗包括非特异免疫治疗、特异免疫治疗及免疫检查点抑制剂药物治疗等,以程序性死亡分子-1(programmeddeath-1,PD-1)/程序性死亡受体-配体 1(PD-L1)单克隆抗体、抗细胞毒性T淋巴细胞抗原4(CTLA-4)单克隆抗体等为代表的免疫检查点抑制剂免疫治疗和CAR-T(chimeric antigen receptor T-Cell immunotherapy)为代表的细胞免疫治疗已成为HCC的研究热点[65-66]。PD-1抑制剂Nivolumab治疗进展期HCC的Ⅰ~Ⅱ期临床研究(CheckMate 040)结果已发表,262例进展期HCC患者治疗后总体客观缓解率约为20%,而且某些缓解具有持久性。此外,大量患者治疗后疾病保持长期稳定,1年总生存率为60%~70%,且其疗效与肿瘤是否表达PD-L1无关,与是否使用过索拉非尼无关。结果表明Nivolumab治疗进展期HCC安全有效,有望成为进展期HCC的标准治疗之一,更有可能进入一线治疗[67]。但在术后复发防治方面的研究尚无报道。
过继性非特异免疫治疗在肝癌术后辅助治疗中的作用已有较多临床试验证实。文献报道肝癌切除术后6个月内通过细胞因子体外激活自体淋巴细胞输注治疗,可降低术后复发,显著改善无瘤生存,但对总生存率无影响[68]。一项针对HCC术后辅助过继免疫治疗的荟萃分析显示,过继免疫治疗可以显著降低术后1年和3年复发风险,但对3年生存率无显著影响[69]。辅助性细胞因子诱导杀伤细胞(CIK)治疗在降低HCC复发率和延长生存期方面也具有应用前景。290例接受根治性治疗的HCC患者,其中145例接受术后CIK细胞输注,另外145例设为对照组。结果显示CIK 治疗组总生存期(HR=0.55,95%CI:0.33~0.92)和无病生存率(HR=0.59,95%CI:0.42~0.83)显著优于对照组。治疗组中单因素分析显示肿瘤组织高表达PD-L1和伴有大量PD-1阳性肿瘤浸润淋巴细胞者(PD-1+TILs)可从治疗中获益。多因素分析显示PD-1+TILs数量高是唯一的独立预测因子。相比之下,在单纯手术组,PD-1/PD-L1和患者生存率无显著相关性。大量的PD-1+TILs可作为HCC术后CIK细胞辅助治疗的潜在生物标志物(ASCO2017 Abstract e15680)。
特异性个体化肿瘤疫苗术后辅助治疗具有光明的前景。应用自体福尔马林固定的肿瘤疫苗(AFTV)进行术后特异性免疫辅助治疗Ⅱ期临床试验,共纳入41例接受根治性手术治疗的HCC患者,随机分为治疗组(19例)和对照组(22例),术后4~6周治疗组开始进行3次皮内注射接种疫苗,每次间隔2周。结果治疗组复发风险降低81%(P=0.003)。免疫接种可显著延长初次复发时间(P=0.003),改善无复发生存率(P=0.003)和总生存率(P=0.01)[70-71]。研究表明 AFTV治疗安全可行,且对预防HCC术后复发有效。最近美国和德国两个团队在Nature发表论文[72-73],针对患者肿瘤突变定制的个性化疫苗,在恶性黑色素瘤患者治疗中获得巨大成功,虽然目前样本量较小,但通过筛查个体化的肿瘤特异性抗原,通过基因工程体外对其抗原性进行放大,激活T淋巴细胞产生主动免疫,从而达到治疗作用。其治疗原理与CAR-T类似,但技术流程更简单易行。免疫治疗是最有希望帮助人类攻克癌症的治疗方法。
HCC术后高复发率已成为进一步提高患者生存的主要障碍。HCC复发转移的机制及预测和干预是近年来的研究热点。通过不断努力,对HCC术后复发转移的风险进行精确评估和识别,对高危患者进行早期、综合、有效地辅助干预治疗可降低复发,改善患者预后。术后抗病毒治疗和干扰素辅助治疗可降低HCC患者复发风险,对经过选择的患者行辅助放疗可改善预后。辅助性TACE和索拉非尼靶向治疗的作用尚需进一步评估。近年来免疫治疗技术不断发展,必将为转移复发的预测和防治带来无限光明的前景。
[1] Torre LA,Bray F,Siegel RL,et al.Global cancer statistics,2012[J].CA Cancer J Clin,2015,65(2):87-108.
[2] El-Serag HB.Hepatocellular carcinoma[J].N Engl J Med,2011,365(12):1118-1127.
[3] Imamura H,Matsuyama Y,Tanaka E,et al.Risk factors contributing to early and late phase intrahepatic recurrence of hepatocellular carcinoma after hepatectomy[J].J Hepatol,2003,38(2):200-207.
[4] Poon RT,Fan ST,Ng IO,et al.Different risk factors and prognosis for early and late intrahepatic recurrence after resection of hepatocellular carcinoma[J].Cancer,2000,89(3):500-507.
[5] Tung-Ping Poon R,Fan ST,Wong J.Risk factors,prevention,and management of postoperative recurrence after resection of hepatocellular carcinoma[J].Ann Surg,2000,232(1):10-24.
[6] Papatheodoridis GV,Lampertico P,Manolakopoulos S,et al.Incidence of hepatocellular carcinoma in chronic hepatitis B patients receiving nucleos(t)ide therapy:a systematic review[J].J Hepatol,2010,53(2):348-356.
[7] Kubo S,Hirohashi K,Tanaka H,et al.Effect of viral status on recurrence after liver resection for patients with hepatitis B virus-related hepatocellular carcinoma[J].Cancer,2000,88(5):1016-1024.
[8] Qin LX.Inflammatory immune responses in tumor microenvironment and metastasis of hepatocellular carcinoma[J].Cancer Microenviron,2012,5(3):203-209.
[9] Liu PH,Hsu CY,Hsia CY,et al.Prognosis of hepatocellular carcinoma:assessment of eleven staging systems[J].J Hepatol,2016,64(3):601-608.
[10] Qin LX,Tang ZY,Sham JS,et al.The association of chromosome 8p deletion and tumor metastasis in human hepatocellular carcinoma[J].Cancer Res,1999,59(22):5662-5665.
[11] Qin LX,Tang ZY,Ye SL,et al.Chromosome 8p deletion is associated with metastasis of human hepatocellular carcinoma when high and low metastaticmodels are compared[J].J Cancer Res Clin Oncol,2001,127(8):482-488.
[12] Ren N,Qin LX,Tu H,et al.The prognostic value of circulating plasma DNA level and its allelic imbalance on chromosome 8p in patientswith hepatocellular carcinoma[J].JCancer Res Clin Oncol,2006,132(6):399-407.
[13] Pang JZ,Qin LX,Ren N,et al.Loss of heterozygosity at D8S298 is a predictor for long-term survival of patients with tumor-node-metastasis stage I of hepatocellular carcinoma[J].Clin Cancer Res,2007,13(24):7363-7369.
[14] Ye QH,Qin LX,Forgues M,et al.Predicting hepatitis B virus-positive metastatic hepatocellular carcinomas using gene expression profiling and supervised machine learning[J].Nat Med,2003,9(4):416-423.
[15] Huang H,Zhang XF,Zhou HJ,et al.Expression and prognostic significance of osteopontin and caspase-3 in hepatocellular carcinoma patients after curative resection[J].Cancer Sci,2010,101(5):1314-1319.
[16] Zhou C,Zhou HJ,Zhang XF,et al.Postoperative serum osteopontin level is a novel monitor for treatment response and tumor recurrence after resection of hepatitis B-related hepatocellular carcinoma[J].Ann Surg Oncol,2013,20(3):929-937.
[17] Xue YH,Zhang XF,Dong QZ,et al.Thrombin is a therapeutic target for metastatic osteopontin-positive hepatocellular carcinoma[J].Hepatology,2010,52(6):2012-2022.
[18] Roessler S,Jia HL,Budhu A,et al.A unique metastasis gene signature enables prediction of tumor relapse in early-stage hepatocellular carcinoma patients[J].Cancer Res,2010,70(24):10202-10212.
[19] Budhu A,Forgues M,Ye QH,et al.Prediction of venous metastases,recurrence,and prognosis in hepatocellular carcinoma based on a unique immune response signature of the liver microenvironment[J].Cancer Cell,2006,10(2):99-111.
[20] Zhou H,Huang H,Shi J,et al.Prognostic value of interleukin 2 and interleukin 15 in peritumoral hepatic tissues for patients with hepatitis B-related hepatocellular carcinoma after curative resection[J].Gut,2010,59(12):1699-1708.
[21] Haber DA,Velculescu VE.Blood-based analyses of cancer:circulating tumor cells and circulating tumor DNA[J].Cancer Discov,2014,4(6):650-661.
[22] Schwarzenbach H,Hoon DS,Pantel K.Cell-free nucleic acids as biomarkers in cancer patients[J].Nat Rev Cancer,2011,11(6):426-437.
[23] Ijichi M,Takayama T,Matsumura M,et al.alpha-Fetoprotein mRNA in the circulation as a predictor of postsurgical recurrence of hepatocel-lular carcinoma:a prospective study[J].Hepatology,2002,35(4):853-860.
[24] Hüsemann Y,Geigl JB,Schubert F,et al.Systemic spread is an early step in breast cancer[J].Cancer Cell,2008,13(1):58-68.
[25] Xu W,Cao L,Chen L,et al.Isolation of circulating tumor cells in patients with hepatocellular carcinoma using a novel cell separation strategy[J].Clin Cancer Res,2011,17(11):3783-3793.
[26] Liu S,Li N,Yu X,et al.Expression of intercellular adhesion molecule 1 by hepatocellular carcinoma stem cells and circulating tumor cells[J].Gastroenterology,2013,144(5):1031-1041.
[27] Schulze K,Gasch C,Staufer K,et al.Presence of EpCAM-positive circulating tumor cells as biomarker for systemic disease strongly correlates to survival in patients with hepatocellular carcinoma[J].Int J Cancer,2013,133(9):2165-2171.
[28] Demory Beckler M,Higginbotham JN,Franklin JL,et al.Proteomic analysis of exosomes from mutant KRAS colon cancer cells identifies intercellular transfer of mutant KRAS[J].Mol Cell Proteomics,2013,12(2):343-355.
[29] De Vrij J,Maas SL,Kwappenberg KM,et al.Glioblastoma-derived extracellular vesicles modify the phenotype of monocytic cells[J].Int J Cancer,2015,137(7):1630-1642.
[30] Luga V,Zhang L,Viloria-Petit AM,et al.Exosomes mediate stromal mobilization of autocrine Wnt-PCP signaling in breast cancer cell migration[J].Cell,2012,151(7):1542-1556.
[31]Schwartz JD,Schwartz M,Mandeli J,et al.Neoadjuvant and adjuvant therapy for resectable hepatocellular carcinoma:review of the randomised clinical trials[J].Lancet Oncol,2002,3(10):593-603.
[32]Sun HC,Tang ZY.Preventive treatments for recurrence after curative resection of hepatocellular carcinoma--a literature review of randomized control trials[J].World J Gastroenterol,2003,9(4):635-640.
[33] Chua TC,Liauw W,Saxena A,et al.Systematic review of neoadjuvant transarterial chemoembolization for resectable hepatocellular carcinoma[J].Liver Int,2010,30(2):166-174.
[34] Lau WY,Leung TW,Ho SK,et al.Adjuvant intra-arterial iodine-131-labelled lipiodol for resectable hepatocellular carcinoma:a prospective randomised trial[J].Lancet,1999,353(9155):797-801.
[35] Lau WY,Lai EC,Leung TW,et al.Adjuvant intra-arterial iodine-131-labeled lipiodolfor resectable hepatocellular carcinoma:a prospective randomized trial-update on 5-year and 10-year survival[J].Ann Surg,2008,247(1):43-48.
[36] Izumi R,Shimizu K,Iyobe T,et al.Postoperative adjuvant hepatic arterial infusion of Lipiodol containing anticancer drugs in patients with hepatocellular carcinoma[J].Hepatology,1994,20(2):295-301.
[37] Lai EC,Lo CM,Fan ST,et al.Postoperative adjuvant chemotherapy after curative resection of hepatocellular carcinoma:a randomized controlled trial[J].Arch Surg,1998,133(2):183-188.
[38] Sieghart W,Hucke F,Pinter M,et al.The ART of decision making:retreatment with transarterial chemoembolization in patients with hepatocellular carcinoma[J].Hepatology,2013,57(6):2261-2273.
[39] Ren ZG,Lin ZY,Xia JL,et al.Postoperative adjuvant arterial chemoembolization improves survival of hepatocellular carcinoma patients with risk factors for residual tumor:a retrospective control study[J].World J Gastroenterol,2004,10(19):2791-2794.
[40] Wang Z,Li Z,Ji Y.Postoperative transcatheter arterial chemoembolization should be recommended in the hepatocellular carcinoma treatment guidelines of the American association for the study of liver diseases[J].Hepatology,2011,54(4):1489-1490.
[41] Li KW,Li X,Wen TF,et al.The effect of postoperative TACE on prognosis of HCC:an update[J].Hepatogastroenterology,2013,60(122):248-251.
[42] Poon RT,Fan ST,Lo CM,et al.Long-term prognosis after resection of hepatocellular carcinoma associated with hepatitis B-related cirrhosis[J].J Clin Oncol,2000,18(5):1094-1101.
[43] Zhang J,Jiang TY,Jiang BG,et al.RMP predicts survival and adjuvant TACE response in hepatocellular carcinoma[J].Oncotarget,2015,6(5):3432-3442.
[44] Zhang B,Liu K,Zhang J,et al.Glutamine synthetase predicts adjuvantTACEresponseinhepatocellularcarcinoma[J].IntJClinExpMed,2015,8(11):20722-20731.
[45] Spinzi G.Sorafenib in advanced hepatocellular carcinoma[J].N Engl J Med,2008,359(23):2497-2498.
[46] Cheng AL,Kang YK,Chen Z,et al.Efficacy and safety of sorafenib in patients in the Asia-Pacific region with advanced hepatocellular carcinoma:a phase III randomised,double-blind,placebo-controlled trial[J].Lancet Oncol,2009,10(1):25-34.
[47] Wang SN,Chuang SC,Lee KT.Efficacy of sorafenib as adjuvant therapy to prevent early recurrence of hepatocellular carcinoma after curative surgery:a pilot study[J].Hepatol Res,2014,44(5):523-531.
[48] Printz C.Clinical trials of note.Sorafenib as adjuvant treatment in the prevention of disease recurrence in patients with hepatocellular carcinoma(HCC)(STORM)[J].Cancer,2009,115(20):4646.
[49] Wu JC,Huang YH,Chau GY,et al.Risk factors for early and late recurrence in hepatitis B-related hepatocellular carcinoma[J].J Hepatol,2009,51(5):890-897.
[50] Sohn W,Paik YH,Kim JM,et al.HBV DNA and HBsAg levels as risk predictors of early and late recurrence after curative resection of HBV-related hepatocellular carcinoma[J].Ann Surg Oncol,2014,21(7):2429-2435.
[51] Wu CY,Chen YJ,Ho HJ,et al.Association between nucleoside analogues and risk of hepatitis B virus-related hepatocellular carcinoma recurrence following liver resection[J].JAMA,2012,308(18):1906-1914.
[52] Yin J,Li N,Han Y,et al.Effect of antiviral treatment with nucleotide/nucleoside analogs on postoperative prognosis of hepatitis B virus-related hepatocellular carcinoma:a two-stage longitudinal clinical study[J].J Clin Oncol,2013,31(29):3647-3655.
[53] Wong JS,Wong GL,Tsoi KK,et al.Meta-analysis:the efficacy of anti-viral therapy in prevention of recurrence after curative treatment of chronic hepatitis B-related hepatocellular carcinoma[J].Aliment Pharmacol Ther,2011,33(10):1104-1112.
[54] Chuma M,Hige S,Kamiyama T,et al.The influence of hepatitis B DNA level and antiviral therapy on recurrence after initial curative treatment in patients with hepatocellular carcinoma[J].JGastroenterol,2009,44(9):991-999.
[55] Chan AC,Chok KS,Yuen WK,et al.Impact of antiviral therapy on the survival of patients after major hepatectomy for hepatitis B virusrelated hepatocellular carcinoma[J].Arch Surg,2011,146(6):675-681.
[56] Hasegawa K,Takayama T,Ijichi M,et al.Uracil-tegafur as an adjuvant for hepatocellular carcinoma:a randomized trial[J].Hepatology,2006,44(4):891-895.
[57] Jonasch E,Haluska FG.Interferon in oncological practice:review of interferon biology,clinical applications,and toxicities[J].Oncologist,2001,6(1):34-55.
[58] Sun HC,Tang ZY,Wang L,et al.Postoperative interferon alpha treatment postponed recurrence and improved overall survival in patients after curative resection of HBV-related hepatocellular carcinoma:a randomized clinical trial[J].J Cancer Res Clin Oncol,2006,132(7):458-465.
[59] Lo CM,Liu CL,Chan SC,et al.A randomized,controlled trial of postoperative adjuvant interferon therapy after resection of hepatocellular carcinoma[J].Ann Surg,2007,245(6):831-842.
[60] Chen LT,Chen MF,Li LA,et al.Long-term results of a randomized,observation-controlled,phase III trial of adjuvant interferon Alfa-2b in hepatocellular carcinoma after curative resection[J].Ann Surg,2012,255(1):8-17.
[61] Ikeda K,Arase Y,Saitoh S,et al.Interferon beta prevents recurrence of hepatocellular carcinoma after complete resection or ablation of the primary tumor-A prospective randomized study of hepatitis C virus-related liver cancer[J].Hepatology,2000,32(2):228-232.
[62] Mazzaferro V,Romito R,Schiavo M,et al.Prevention of hepatocellular carcinoma recurrence with alpha-interferon after liver resection in HCV cirrhosis[J].Hepatology,2006,44(6):1543-1554.
[63] Zuo CH,Xia M,Liu JS,et al.Transcatheter arterial chemoembolization combined with interferon-alpha is safe and effective for patients with hepatocellular carcinoma after curative resection[J].Asian Pac J Cancer Prev,2015,16(1):245-251.
[64] Ji J,Shi J,Budhu A,et al.MicroRNA expression,survival,and response to interferon in liver cancer[J].N Engl J Med,2009,361(15):1437-1447.
[65] Topalian SL,Wolchok JD,Chan TA,et al.Immunotherapy:the path to win the war on cancer?[J].Cell,2015,161(2):185-186.
[66] Salama AK,Postow MA,Salama JK.Irradiation and immunotherapy: from concept to the clinic[J].Cancer,2016,122(11):1659-1671.
[67] El-Khoueiry AB,Sangro B,Yau T,et al.Nivolumab in patients with advanced hepatocellular carcinoma (CheckMate 040):an openlabel,non-comparative,phase 1/2 dose escalation and expansion trial[J].Lancet,2017,389(10088):2492-2502.
[68] Takayama T,Sekine T,Makuuchi M,et al.Adoptive immunotherapy to lower postsurgical recurrence rates of hepatocellular carcinoma:a randomised trial[J].Lancet,2000,356(9232):802-807.
[69] Xie F,Zhang X,Li H,et al.Adoptive immunotherapy in postoperative hepatocellular carcinoma:a systemic review[J].PLoS One,2012,7(8):e42879.
[70] Kuang M,Peng BG,Lu MD,et al.Phase II randomized trial of autologous formalin-fixed tumor vaccine for postsurgical recurrence of hepatocellular carcinoma[J].Clin Cancer Res,2004,10(5):1574-1579.
[71] Peng B,Liang L,Chen Z,et al.Autologous tumor vaccine lowering postsurgical recurrent rate of hepatocellular carcinoma[J].Hepatogastroenterology,2006,53(69):409-414.
[72] Ott PA,Hu Z,Keskin DB,et al.An immunogenic personal neoantigen vaccine for patients with melanoma[J].Nature,2017,547(7662):217-221.
[73] Sahin U,Derhovanessian E,Miller M,et al.Personalized RNA mutanome vaccines mobilize poly-specific therapeutic immunity against cancer[J].Nature,2017,547(7662):222-226.