非小细胞肺癌NCCN指南2017第4版讨论（生物标志物）

Predictive and Prognostic Biomarkers 预报和预后性生物标志物

Several biomarkers have emerged as predictive and prognostic markers for NSCLC. A predictive biomarker is indicative of therapeutic efficacy, because there is an interaction between the biomarker and therapy on patient outcome. A prognostic biomarker is indicative of patient survival independent of the treatment received, because the biomarker is an indicator of the innate tumor aggressiveness (see KRAS Mutations at the end of this section). 若干生物标志物已经成为NSCLC的预报和预后性标志物。预报性生物标志物是治疗疗效的指标，因为在生物标志物和治疗之间对患者预后有相互影响。预后性标志物是与患者所接受治疗无关的生存指标，因为该生物标志物是固有的肿瘤侵袭性指标（见本节末的KRAS突变）。

Predictive biomarkers include the ALK fusion oncogene (fusion between ALK and other genes [eg, echinoderm microtubule-associated protein-like 4]), ROS1 gene rearrangements, and sensitizing EGFR mutations (see Principles of Pathologic Review in the NCCN Guidelines for NSCLC). Emerging biomarkers include HER2 (also known as ERBB2) and BRAF V600E mutations, RET gene rearrangements, and high-level MET amplifications or MET exon 14 skipping mutations (see Emerging Targeted Agents for Patients with Genetic Alterations in the NCCN Guidelines for NSCLC). The presence of EGFR exon 19 deletions or exon 21 L858R mutations is predictive of treatment benefit from EGFR tyrosine kinase inhibitor (EGFR-TKI) therapy (ie, erlotinib, gefitinib, afatinib); therefore, these mutations are referred to as sensitizing EGFR mutations (see EGFR Mutations in this Discussion). However, the presence of EGFR exon 19 deletions (LREA) or exon 21 L858R mutations does not appear to be prognostic of survival for patients with NSCLC, independent of therapy. ALK fusion oncogenes (ie, ALK gene rearrangements) and ROS1 rearrangements are predictive biomarkers that have been identified in a small subset of patients with NSCLC; both predict for benefit from crizotinib (see ALK Gene Rearrangements and ROS1 Gene Rearrangements in this Discussion and Principles of Pathologic Review in the NCCN Guidelines for NSCLC). For the 2017 update (Version 1), the NCCN Panel added a new section on ROS1 Gene Rearrangements to the pathology recommendations (see Principles of Pathologic Review in the NCCN Guidelines for NSCLC) Other gene rearrangements (ie, gene fusions) have recently been identified (such RET) that are susceptible to targeted therapies (see Emerging Targeted Agents for Patients with Genetic Alterations in the NCCN Guidelines for NSCLC). 预报性生物标志物包括ALK融合基因（ALK与其他基因[如棘皮动物微管结合蛋白4]融合）、ROS1基因重排以及敏感EGFR突变（见NSCLC NCCN指南中的病理学检查原则）。新兴的生物标记物包括HER2（也称为ERBB2）和BRAF V600E突变、RET基因重排、高水平MET扩增或MET 14外显子跳跃突变（见NSCLC NCCN指南中的具有遗传学改变患者的新兴靶向药物）。存在EGFR外显子19缺失或外显子21 L858R突变预报从表皮生长因子受体酪氨酸激酶抑制剂（EGFR-TKI）治疗（即厄洛替尼、吉非替尼、阿法替尼）治疗中受益;因此，这些突变称为敏感EGFR突变（见本讨论中的EGFR突变）。然而，存在EGFR外显子19缺失（LREA）或21外显子L858R变异似乎不能独立于治疗预示NSCLC患者的生存。间变性淋巴瘤激酶融合癌基因（即ALK基因重组）和ROS1重排是预报性生物标志物，已在NSCLC患者的一个小亚组中确定；两者均预测受益于克唑替尼（见本讨论中的ALK基因重排和ROS1基因重排以及NSCLC NCCN指南中的病理检查原则）。2017第1版更新，NCCN小组增加了一个新的章节，ROS1基因重排病理学推荐（见NSCLC NCCN指南中的病理检查原则）最近已确定其他对靶向治疗敏感的基因重排（即基因融合）（如RET）（见NSCLC NCCN指南中的具有遗传学改变患者的新兴靶向药物）。

Testing for ALK gene rearrangements and EGFR mutations is recommended (category 1 for both) in the NSCLC algorithm for patients with non-squamous NSCLC or NSCLC not otherwise specified (NOS) so that patients with these genetic abnormalities can receive effective treatment with targeted agents such as erlotinib, gefitinib, afatinib, and crizotinib (see Targeted Therapies in this Discussion and the NCCN Guidelines for NSCLC). Testing for ROS1 rearrangements (category 2A) is also recommended in the NCCN Guidelines. Although rare, patients with ALK rearrangements or EGFR mutations can have mixed squamous cell histology. Therefore, testing for ALK rearrangements, ROS1 rearrangements, and EGFR mutations can be considered in patients with squamous cell histology if they are never smokers, small biopsy specimens were used for testing, or mixed histology was reported. EGFR, KRAS, ROS1, and ALK genetic alterations do not usually overlap. 在NSCLC工作步骤中，对于非鳞NSCLC和NSCLC非特指（NOS）患者，推荐检测ALK基因重排和EGFR突变（均为1类），以便这些遗传异常的患者可以接受有效的靶向药物治疗，如厄洛替尼、吉非替尼、阿法替尼和克唑替尼（见本讨论和NSCLC NCCN指南中的靶向治疗）。在NCCN指南中还推荐检测ROS1重排（2A类）。尽管罕见，ALK重排或EGFR突变的患者可以有混合的鳞状细胞组织学成分。因此，有报道，在鳞状细胞组织患者中如果他们从不吸烟、有可用于检测的小活检标本或混合性组织学，可以考虑ALK重排、ROS1重排和EGFR突变检测。EGFR、KRAS、ROS1和ALK遗传学改变通常不重叠。

Patients with NSCLC may have other genetic alterations (see Emerging Targeted Agents for Patients with Genetic Alterations in the NCCN Guidelines for NSCLC). Mutation screening assays for detecting multiple biomarkers simultaneously (eg, Sequenom's MassARRAY(R) system, SNaPshot(R) Multiplex System) have been developed that can detect more than 50 point mutations, including EGFR. However, these multiplex polymerase chain reaction (PCR) systems do not detect gene rearrangements, because they are not point mutations. ROS1 and ALK gene rearrangements can be detected using fluorescence in situ hybridization (FISH) (see ALK Gene Rearrangements and ROS1 Gene Rearrangements in this Discussion). Broad molecular profiling systems, such as next-generation sequencing (NGS) (also known as massively parallel sequencing), can detect panels of mutations and gene rearrangements if the NGS platforms have been designed and validated to detect these genetic alterations. It is important to recognize that NGS requires quality control as much as any other diagnostic technique; because it is primer dependent, the panel of genes and abnormalities detected with NGS will vary depending on the design of the NGS platform. For example, some NGS platforms can detect both mutations and gene rearrangements, as well as copy number variation, but they are not uniformly present in all NGS assays being conducted either commercially or in institutional laboratories. NSCLC患者可能具有其他的遗传学改变（见NSCLC NCCN指南中的具有遗传学改变患者的新兴靶向药物）。已开发出同时检测多个生物标志物的突变筛查分析（如，Sequenom's MassARRAY®系统、SNaPshot®复合系统）可以检测50多个点突变，包括EGFR。不过，这些复合多聚酶链反应（PCR）系统不能检测基因重排，因为它们不是点突变。ROS1和ALK基因重排可采用荧光原位杂交（FISH）检测（见本讨论中的ALK基因重排和ROS1基因重排）。广泛的分子分析系统，例如新一代测序（NGS）（也称为大规模平行测序），可以检出一组突变和基因重排，如果NGS平台对检测这些基因改变已设计并验证。重要的是要认识到，像众多其他任何诊断技术一样，NGS需要质量控制；因为它依赖于引物，NGS检出的一组基因和异常将取决于不同的NGS平台设计。例如，一些NGS平台可以检测基因突变和基因重排，以及拷贝数的变化，但他们不会统一出现在所有的商业或机构实验室进行的NGS分析之中。

Other driver mutations and gene rearrangements (ie, driver events) are being identified such as BRAF V600E mutations, RET gene rearrangements, high-level MET amplification or MET exon 14 skipping mutation, and HER2 (also known as ERBB2). Targeted agents are available for patients with NSCLC who have these other genetic alterations, although they are FDA approved for other indications (see Emerging Targeted Agents for Patients with Genetic Alterations in the NCCN Guidelines for NSCLC). Thus, the NCCN Panel strongly advises broader molecular profiling (also known as precision medicine) to identify rare driver mutations to ensure that patients receive the most appropriate treatment; patients may be eligible for clinical trials for some of these targeted agents. Several online resources are available that describe NSCLC driver events such as DIRECT (DNA-mutation Inventory to Refine and Enhance Cancer Treatment) and My Cancer Genome. The KRAS oncogene is a prognostic biomarker. The presence of KRAS mutations is prognostic of poor survival for patients with NSCLC when compared to the absence of KRAS mutations, independent of therapy (see KRAS Mutations in this Discussion). KRAS mutations are also predictive of lack of benefit from platinum/vinorelbine chemotherapy or EGFR TKI therapy. EGFR, KRAS, ROS1, and ALK genetic alterations do not usually overlap. Sensitizing EGFR TKI therapy is not effective in patients with KRAS mutations, ALK gene rearrangements, or ROS1 rearrangements. 正在确定其他的驱动突变与基因重排（即驱动事件），如BRAF V600E突变、RET基因重排、高水平MET扩增或MET外显子14跳跃突变以及HER2（即ERBB2）。对于具有这些其他遗传学改变的NSCLC患者有可用的靶向药物，尽管FDA批准的是其他适应症（见NSCLC NCCN指南中的具有遗传学改变患者的新兴靶向药物）。因此，NCCN小组强烈建议检测更广泛分子表达谱（也称为精准医学）以识别罕见的驱动突变，确保患者得到最合理的治疗；患者可能适于这些靶向药物中的某些临床试验。目前可用的一些在线资源提供NSCLC驱动事件描述，如DIRECT（改善和提高癌症治疗的DNA突变详细目录）和我的癌症基因组（My Cancer Genome）。KRAS癌基因是一个预后生物标志物。与没有KRAS突变相比，存在KRAS突变预示NSCLC患者的生存差，与治疗无关（见本讨论中的KRAS突变）。KRAS突变也预示不能从铂/长春瑞滨化疗或EGFR TKI治疗获益。EGFR、KRAS、ROS1和ALK遗传学改变通常不重叠。在KRAS突变、ALK基因重排或ROS1重排的患者中，敏感的EGFR TKI治疗是无效的。

EGFR Mutations EGFR突变

In patients with NSCLC, the most commonly found EGFR mutations are deletions in exon 19 (Exon19del [with conserved deletion of the LREA sequence] in 45% of patients with EGFR mutations) and a mutation in exon 21 (L858R in 40%). Both mutations result in activation of the tyrosine kinase domain, and both are associated with sensitivity to the small molecule TKIs, such as erlotinib, gefitinib, and afatinib (see Targeted Therapies in this Discussion). Thus, these mutations are referred to as sensitizing EGFR mutations. Previously, erlotinib was commonly used in the United States in patients with sensitizing EGFR mutations because of restrictions on the use of gefitinib. However, gefitinib was recently re-approved by the FDA based on a phase 4 study and is now available in the United States. Afatinib is an oral TKI that inhibits the entire ErbB/HER family of receptors including EGFR and HER2. The FDA has approved afatinib for first-line treatment of patients with metastatic non-squamous NSCLC who have sensitizing EGFR mutations. NSCLC患者最常见的EGFR突变是外显子19缺失（Exon19del[合并LREA序列保守缺失]占EGFR突变患者的45%）和外显子21突变（L858R占40%）。两种突变都导致酪氨酸激酶结构域的活化，且两者均与小分子TKIs如厄洛替尼、吉非替尼及阿法替尼的敏感性有关（见本讨论中的靶向治疗）。因此，这些突变称为敏感EGFR突变。从前在美国由于限制吉非替尼的使用，敏感EGFR突变的患者常用厄洛替尼。然而，基于一项4期研究，FDA最近重新审批通过吉非替尼，因此目前在美国可以使用。阿法替尼是一种口服的酪氨酸激酶抑制剂，可抑制全部的ERBB/HER受体家族包括EGFR和HER2。FDA已批准阿法替尼用于具有敏感EGFR突变的转移性非鳞NSCLC患者的一线治疗。

These sensitizing EGFR mutations are found in approximately 10% of Caucasian patients with NSCLC and up to 50% of Asian patients. Other drug-sensitive mutations include point mutations at exon 21 (L861Q) and exon 18 (G719X). Primary resistance to TKI therapy is associated with KRAS mutations and ALK or ROS1 gene rearrangements. Patients with exon 20 insertion mutations are also resistant to TKIs. EGFR T790M is a mutation associated with acquired resistance to EGFR TKI therapy and has been reported in about 60% of patients with disease progression after initial response to erlotinib, gefitinib, or afatinib. Most patients with sensitizing EGFR mutations become resistant to erlotinib, gefitinib, or afatinib after about 9 to 13 months of EGFR TKI therapy. However, studies suggest T790M may also occur in patients who have not previously received EGFR TKI therapy, although this is a rare event. Osimertinib is recommended (category 1) as second-line and beyond (subsequent) therapy for patients with EGFR T790M who have progressed on sensitizing EGFR TKI therapy such as, erlotinib, gefitinib, afatinib (see Osimertinib in this Discussion). Acquired resistance may also be associated with histologic transformation from NSCLC to SCLC and with epithelial to mesenchymal transition (see Principles of Pathologic Review in the NCCN Guidelines for NSCLC). 在大约10%的白种人NSCLC患者和高达50%的亚洲患者中发现这些敏感EGFR基因突变。其他的药物敏感突变包括外显子21（L861Q）和外显子18（G719X）点突变。对TKI治疗原发耐药与KRAS突变和ALK或ROS1基因重排有关。外显子20插入突变的患者也对酪氨酸激酶抑制剂耐药。EGFR T790M是一种与对EGFR TKI治疗获得性耐药有关的突变，已报道大约60%的患者在初始厄洛替尼、吉非替尼或阿法替尼治疗有效后疾病进展。大多数具有敏感EGFR突变的患者在大约酪氨酸激酶抑制剂治疗9至13个月后变成对厄洛替尼、吉非替尼或阿法替尼耐药。但是，研究表明，在既往未接受酪氨酸激酶抑制剂治疗的患者中也可能出现T790M，尽管这是一个罕见的事件。对于敏感EGFR TKI如厄洛替尼、吉非替尼、阿法替尼治疗已经进展、EGFR T790M的患者，推荐奥希替尼（1类）作为二线及以上（后续）治疗（见本讨论中的奥希替尼）。获得性耐药可能也与组织学从NSCLC转变为小细胞肺癌以及上皮间质转化有关（见NSCLC NCCn指南中的病理学检查原则）。

DNA mutational analysis is the preferred method to assess for EGFR status. Various DNA mutation detection assays can be used to determine the EGFR mutation status in tumor cells. Direct sequencing of DNA corresponding to exons 18 to 21 (or just testing for exons 19 and 21) is a reasonable approach; however, more sensitive methods are available. Mutation screening assays using multiplex PCR (eg, Sequenom's MassARRAY(R) system, SNaPshot(R) Multiplex System) can detect more than 50 point mutations, including EGFR. NGS can also be used to detect EGFR mutations. DNA突变分析是评价EGFR状态的首选方法。各种DNA突变检测分析可用于确定肿瘤细胞的EGFR突变状态。对外显子18至21（或只是检测外显子19和21）相应的DNA直接测序是一个合理的方法；不过，有更敏感的方法可用。使用多路传输PCR（如，Sequenom's MassARRAY®系统、SNaPshot®复合系统）突变筛查分析可以检测50多个点突变，包括EGFR。NGS也可以用来检测EGFR突变。

The predictive effects of the drug-sensitive EGFR mutations— Exon19del (LREA deletion) and L858R—are well defined. Patients with these mutations have a significantly better response to erlotinib, gefitinib, or afatinib. Retrospective studies have shown an objective response rate of approximately 80% with a median progression-free survival (PFS) of 13 months to single-agent EGFR TKI therapy in patients with a bronchioloalveolar variant of adenocarcinoma and a sensitizing EGFR mutation. A prospective study has shown that the objective response rate in North American patients with non-squamous NSCLC and sensitizing EGFR mutations (53% Exon19del [LREA deletion], 26% L858R, and 21% other mutations) is 55% with a median PFS of 9.2 months. EGFR mutation testing is not usually recommended in patients with pure squamous cell carcinoma unless they never smoked, if only a small biopsy specimen (ie, not a surgical resection) was used to assess histology, or if the histology is mixed. Data suggest that EGFR mutations can occur in patients with adenosquamous carcinoma, which is harder to discriminate from squamous cell carcinoma in small specimens. 药物敏感EGFR突变的预报效果——外显子19删失（LREA缺失）和L858R——意义明确。具有这些突变的患者对厄洛替尼、吉非替尼或阿法替尼有显著更好的应答。回顾性研究表明，在腺癌支气管肺泡变种且敏感EGFR突变的患者中，单药EGFR TKI治疗的客观缓解率约80%，中位无进展生存期（PFS）13个月。一项前瞻性研究表明，非鳞NSCLC且敏感EGFR突变的北美患者的客观缓解率（外显子19删失[LREA缺失]53%、L858R 26%、其他突变21%）是55%，中位PFS为9.2个月。在纯鳞状细胞癌患者中，如果用于组织学评估的只是一个小活检标本（即，非手术切除），或者如果组织学是混合性，一般不建议EGFR突变检测，除非从不吸烟。数据表明，在腺鳞癌患者中可以存在EGFR突变，这在小样本中是很难与鳞状细胞癌区分的。

Data show that erlotinib, gefitinib, or afatinib (instead of standard first-line chemotherapy) should be used as first-line systemic therapy in patients with sensitizing EGFR mutations documented before first-line therapy. PFS is improved with use of EGFR TKI in patients with sensitizing EGFR mutations when compared with standard chemotherapy, although overall survival is not statistically different. Patients receiving erlotinib have fewer treatment-related severe side effects and deaths when compared with those receiving chemotherapy. A phase 4 trial showed that gefitinib is safe and effective in patients with sensitizing EGFR mutations. Based on these data and the FDA approvals, erlotinib and gefitinib are recommended (category 1) as first-line systemic therapy in patients with sensitizing EGFR mutations. In a phase 3 randomized trial, patients receiving afatinib had decreased cough, decreased dyspnea, and improved health-related quality of life when compared with those receiving cisplatin/pemetrexed. Based on these data and the FDA approval, afatinib is also recommended (category 1) as first-line systemic therapy in patients with sensitizing EGFR mutations. However, afatinib was potentially associated with 4 treatment-related deaths, whereas there were none in the chemotherapy group. A combined analysis (LUX 3 and LUX 6) reported a survival advantage in patients with exon 19 deletions who received afatinib when compared with chemotherapy. 数据显示，在一线治疗前证实具有敏感EGFR突变的患者中，厄洛替尼、吉非替尼或阿法替尼（而不是标准的一线化疗）应作为一线全身治疗。在具有敏感EGFR突变的患者中，与标准化疗相比，使用EGFR TKI改善无进展生存期，尽管总生存期无统计学差异。与接受化疗者相比，接受厄洛替尼的患者治疗相关的严重不良事件和死亡更少。一项4期试验表明，在具有敏感EGFR突变的患者中，吉非替尼是安全有效的。基于这些数据和FDA的批准，在具有敏感EGFR突变的患者中，推荐厄洛替尼和吉非替尼（1类）作为一线全身治疗。在一项3期随机试验中，与接受顺铂/培美曲塞者相比，接受阿法替尼的患者咳嗽减轻、呼吸困难减轻、生活质量改善。基于这些数据和FDA的批准，在具有敏感EGFR突变的患者中，还推荐阿法替尼（1类）作为一线全身治疗。不过，阿法替尼可能与4例治疗相关的死亡有关，而化疗组没有。LUX 3和LUX 6的一项联合分析报告，在具有外显子19缺失的患者中，与化疗相比，接受阿法替尼者具有生存优势。

ALK Gene Rearrangements ALK基因重排

Estimates are that 2% to 7% of patients with NSCLC have ALK gene rearrangements, about 10,000 of whom live in the United States. Patients with ALK rearrangements are resistant to EGFR TKIs but have similar clinical characteristics to those with EGFR mutations (ie, adenocarcinoma histology, never smokers, light smokers) except they are more likely to be men and may be younger. In these selected populations, estimates are that about 30% of patients will have ALK rearrangements. ALK rearrangements are not routinely found in patients with squamous cell carcinoma. Although rare, patients with ALK gene rearrangements can have mixed squamous cell histology. It can be challenging to accurately determine histology in small biopsy specimens; thus, patients may have mixed squamous cell histology (or squamous components) instead of pure squamous cell. The NCCN Panel recommends testing for ALK rearrangements if small biopsy specimens were used to assess histology, mixed histology was reported, or patients never smoked. A molecular diagnostic test (using FISH) has been approved by the FDA for detecting ALK rearrangements and is a prerequisite before treatment with crizotinib. Rapid prescreening with IHC to assess for ALK rearrangements can be done; if positive, FISH analysis can confirm ALK positivity. NGS can also be used to assess whether ALK rearrangements are present, if the platform has been appropriately designed and validated to detect ALK rearrangements. 据估计，2%至7%的NSCLC患者有ALK基因重排，其中约有10000人生活在美国。具有ALK重排的患者对EGFR TKIs耐药，但是有与EGFR突变者相似的临床特征（如腺癌组织学、从不吸烟、轻度吸烟），除了他们更可能是男性、可能较年轻。在这些选择性人群中，据估计，约30%的患者有ALK重排。在鳞状细胞癌患者中ALK重排不常见。尽管罕见，具有ALK基因重排的患者可以有混合的鳞状细胞组织学成分。在小活检标本中准确确定组织学是富有挑战性的；因此，患者可能有混合的鳞状细胞组织学（或鳞状上皮成分）而非纯的鳞状细胞。如果组织学评估使用的是小活检标本、报告是混合型或患者从不吸烟，NCCN小组推荐检测ALK重排。FDA已批准分子诊断（使用FISH）检测ALK重排，并且是克唑替尼治疗前的一个先决条件。可以使用免疫组化快速预筛评估ALK重排；如果阳性，FISH分析可确认ALK阳性。NGS（新一代测序技术）也可用来评估是否存在ALK重排，如果该平台已针对检测ALK重排适当设计并验证。

Crizotinib—an inhibitor of ALK, ROS1, and some MET tyrosine kinases (high-level MET amplification or MET exon 14 skipping mutation)—is approved by the FDA for patients with locally advanced or metastatic NSCLC who have ALK gene rearrangements (ie, ALK-positive disease) or ROS1 rearrangements. Crizotinib yields very high response rates (>60%) when used in patients with advanced NSCLC who have ALK rearrangements, including those with brain metastases. Crizotinib has relatively few side effects (eg, eye disorders, edema, transient changes in renal function). However, a few patients have had life-threatening pneumonitis; crizotinib should be discontinued in these patients. Patients whose disease responds to crizotinib may have rapid improvement in symptoms (eg, cough, dyspnea, pain); median time to progression on crizotinib is about 7 months to 1 year. 克唑替尼——一种ALK、ROS1和部分MET酪氨酸激酶抑制剂（高水平MET扩增或MET外显子14跳跃突变）——被FDA批准用于治疗有ALK基因重排（即ALK阳性）或ROS1重排的局部晚期或转移性NSCLC患者。当克唑替尼用于有ALK重排的晚期NSCLC患者、包括脑转移患者时，可获得非常高的有效率（＞60%）。克唑替尼的副作用（如，眼部疾病、水肿、一过性肾功能变化）相对较少。不过，少数患者有危及生命的肺炎；这些患者应该停用克唑替尼。对克唑替尼应答的患者症状（如咳嗽、呼吸困难、疼痛）迅速改善；克唑替尼中位疾病进展时间大约是7个月到1年。

Randomized phase 3 trials have compared crizotinib with standard second-line (ie, subsequent) chemotherapy (PROFILE 1007) and with standard first-line therapy (PROFILE 1014). First-line therapy with crizotinib improved PFS, response rate (74% vs. 45%; P < .001), lung cancer symptoms, and quality of life when compared with chemotherapy (pemetrexed with either cisplatin or carboplatin). Based on this trial, crizotinib is recommended (category 1) for first-line therapy in patients with ALK-positive NSCLC (see the NCCN Guidelines for NSCLC). Subsequent therapy with crizotinib improved PFS (7.7 vs. 3.0 months; P < .001) and response rate (65% vs. 20%; P < .001) when compared with single-agent therapy (either docetaxel or pemetrexed) in patients with ALK-positive NSCLC who had progressed after first-line chemotherapy. Based on this trial, crizotinib is recommended as subsequent therapy in patients with ALK-positive disease. The phrase subsequent therapy was recently substituted for the terms second-line or beyond systemic therapy, because the line of therapy may vary depending on previous treatment with targeted agents. 随机3期试验将克唑替尼与标准二线（即后续）治疗（PROFILE 1007）以及标准一线治疗（PROFILE 1014）进行了对比。与化疗（培美曲塞联合顺铂或卡铂）相比，克唑替尼一线治疗改善PFS、有效率（74%对45%；P<0.001）、肺癌的症状及生活质量。基于该试验，推荐克唑替尼（1类）用于ALK阳性NSCLC患者的一线治疗（见NSCLC NCCN指南）。在一线化疗后进展、ALK阳性的NSCLC患者中，与单药治疗（多西他赛或培美曲塞）相比，克唑替尼后续治疗改善PFS（7.7对3.0个月；P<0.001）和有效率（65%对20%；P<0.001）。基于该试验，推荐克唑替尼作为ALK阳性疾病患者的后续治疗。短语“后续治疗”最近代替了措辞“二线或以上全身治疗”，因为治疗的“线”可能由于既往靶向药物治疗而有所不同。

For patients who progress on crizotinib, second-generation ALK inhibitors include ceritinib and alectinib; others are in development. Ceritinib is an orally active TKI of ALK, which also inhibits the insulin-like growth factor–1 (IGF-1) receptor but not MET. An expanded phase 1 trial showed that ceritinib was very active in 122 patients with locally advanced or metastatic NSCLC who have ALK gene rearrangements. The overall response rate to ceritinib was 56% in patients who had previously received crizotinib; the median PFS was 7 months. Based on this study, ceritinib was approved by the FDA for patients with ALK-positive metastatic NSCLC who progress on or are intolerant to crizotinib. The NCCN Panel recommends ceritinib for patients with ALK-positive metastatic NSCLC who have progressed on crizotinib or are intolerant to crizotinib based on the data from Shaw et al and FDA approval. 对于克唑替尼进展的患者，二代ALK抑制剂包括色瑞替尼和阿雷替尼；其他的在开发中。色瑞替尼是一种口服有效的ALK TKI，还抑制胰岛素样生长因子-1（IGF-1）受体但不抑制MET。一项扩大1期试验表明，在122例有ALK基因重排的局部晚期或转移性NSCLC患者中，色瑞替尼非常有效。在既往接受克唑替尼的患者中，色瑞替尼的总有效率是56%；中位PFS是7个月。基于该研究，FDA批准色瑞替尼用于克唑替尼进展或不能耐受、ALK阳性的转移性NSCLC患者。基于Shaw等的数据和FDA的批准，NCCN专家组推荐色瑞替尼用于ALK阳性、克唑替尼已经进展或对克唑替尼不能耐受的转移性NSCLC患者 。

Alectinib is another oral TKI of ALK, which also inhibits RET but not MET or ROS1. Two phase 2 trials in patients with ALK rearrangements showed that alectinib was very active in those who had progressed on crizotinib. In the larger trial (138 patients) by Ou et al, patients on alectinib had a response rate of 50% (95% CI, 41%–59%), and median duration of response of 11.2 months (95% CI, 9.6 months to not reached). For central nervous system (CNS) disease, the control rate was 83% (95% CI, 74%–91%), and the median duration of response was 10.3 months (95% CI, 7.6–11.2 months). Of 84 patients with baseline CNS metastases, 23 (27%) had a complete CNS response to alectinib. Of 23 patients with baseline CNS metastases and no previous brain RT, 10 (43%) had a complete CNS response to alectinib. Most adverse events were only grade 1 to 2 (constipation, fatigue, and peripheral edema); 4 patients (3%) had grade 3 dyspnea. One death due to intestinal perforation may have been related to alectinib. The other phase 2 trial in 87 patients with ALK-positive NSCLC who had progressed on crizotinib reported that 48% of patients had an objective response to alectinib. Of 16 patients with baseline CNS metastases, 4 (25%) achieved a complete response in the CNS; 11 of these patients had previously received RT. One treatment-related death occurred due to hemorrhage. Based on these studies, alectinib was approved by the FDA for patients with ALK-positive metastatic NSCLC who progress on or are intolerant to crizotinib. The NCCN Panel recommends alectinib (category 2A) for patients with ALK-positive metastatic NSCLC who have progressed on crizotinib or are intolerant to crizotinib based on these 2 trials and FDA approval. 阿雷替尼是另一个口服的ALK TKI，也抑制RET但不抑制MET或ROS1。ALK重排患者的两项2期试验显示，在克唑替尼已经进展的患者中阿雷替尼非常有效。在Ou等人的更大型试验（138例患者）中，阿雷替尼患者的有效率为50%（95% CI，41%-59%）、中位疗效持续时间11.2个月（95% CI，9.6个月至未达到）。对于中枢神经系统（CNS）病变，控制率是83%（95% CI，74%-91%），中位疗效持续时间是10.3个月（95% CI，7.6-11.2个月）。基线CNS转移的84例患者中，阿雷替尼治疗后23例（27%）CNS病变完全缓解。基线CNS转移且既往脑放疗的23例患者中，阿雷替尼治疗后10例（43%）CNS病变完全缓解。大多数不良事件仅为1至2级（便秘、疲劳和周围性水肿）；4例患者（3%）有3级呼吸困难。1例因肠穿孔死亡，可能与阿雷替尼有关。另外一项在87例ALK阳性、克唑替尼进展的NSCLC患者中的2期试验报道，48%的患者对阿雷替尼有客观应答。16例基线CNS转移的患者中，4例（25%）在CNS中达到完全缓解；其中11例患者曾接受过放疗。发生1例治疗相关的出血死亡。基于这些研究，FDA批准阿雷替尼用于克唑替尼进展或不能耐受、ALK阳性的转移性NSCLC患者。基于这两项研究和FDA的批准，NCCN专家组推荐阿雷替尼（2A类）用于ALK阳性、克唑替尼已经进展或对克唑替尼不能耐受的转移性NSCLC患者 。

ALK or ROS1 rearrangements and sensitizing EGFR mutations are generally mutually exclusive. Thus, erlotinib, gefitinib, and afatinib are not recommended as subsequent therapy in patients with ALK or ROS1 rearrangements who relapse on crizotinib (see ALK Positive: Subsequent Therapy in the NCCN Guidelines for NSCLC). Likewise, crizotinib, ceritinib, and alectinib are not recommended for patients with sensitizing EGFR mutations who relapse on erlotinib, gefitinib, or afatinib. For patients who progress on crizotinib, subsequent treatment for ALK-positive NSCLC includes ceritinib or alectinib (see Ceritinib and Alectinib in this Discussion and the NCCN Guidelines for NSCLC). Continuing crizotinib may also be appropriate for patients who progress on crizotinib. ALK或ROS1重排和敏感EGFR突变通常是相互排斥的。因此，不推荐厄洛替尼、吉非替尼和阿法替尼作为具有ALK或ROS1重排、克唑替尼复发患者的后续治疗（见ALK阳性：NSCLC NCCN指南中的后续治疗）。同样，不推荐克唑替尼、色瑞替尼和阿雷替尼用于厄洛替尼、吉非替尼或阿法替尼复发的具有敏感EGFR突变的患者。对于克唑替尼进展的患者，ALK阳性NSCLC的后续治疗包括色瑞替尼或阿雷替尼（见本讨论以及NSCLC NCCN指南中的色瑞替尼和阿雷替尼）。对于克唑替尼进展的患者继续克唑替尼可能也是合适的。

ROS1 Rearrangements ROS1重排

Although ROS1 is a distinct receptor tyrosine kinase, it is very similar to ALK and members of the insulin receptor family (see Principles of Pathologic Review in the NCCN Guidelines for NSCLC). It is estimated that ROS1 gene rearrangements occur in about 1% to 2% of patients with NSCLC; they occur more frequently in younger women with adenocarcinoma who are never smokers and in those who are negative for EGFR mutations, KRAS mutations, and ALK gene rearrangements (also known as triple negative). Crizotinib is very effective for patients with ROS1 rearrangements with response rates of about 70% including complete responses. In 50 patients, crizotinib yielded a response rate of 66% (95% CI, 51%–79%); the median duration of response was 18 months. The FDA has approved crizotinib for patients with ROS1 rearrangements. 虽然ROS1是一个截然不同的受体酪氨酸激酶，但是其与ALK以及胰岛素受体家族非常相似（见NSCLC NCCN指南中的病理学评估原则）。据估计，约1%至2%的NSCLC患者存在ROS1基因重排；在从不吸烟的腺癌年轻女性中以及EGFR突变、KRAS突变和ALK基因重排阴性（即三阴性）者中更常见。克唑替尼对ROS1重排的患者非常有效，有效率约70%，包括完全缓解。在50例患者中，克唑替尼的有效率达66%（95%CI，51%-79%）；中位无进展生存期是18个月。FDA已批准克唑替尼治疗ROS1重排的患者。

For the 2017 update (Version 1), the NCCN Panel moved the recommendation for ROS1 testing into the main algorithm (and deleted the footnote recommending ROS1 testing), added a new algorithm for ROS1, and added a new section on ROS1 to the molecular diagnostic studies section based on data showing the efficacy of crizotinib for patients with ROS1 rearrangements and on the recent FDA approval (see Principles of Pathologic Review in the NCCN Guidelines for NSCLC). Similar to testing for ALK rearrangements, testing for ROS1 is also done using FISH. NGS can also be used to assess whether ROS1 rearrangements are present, if the platform has been appropriately designed and validated to detect ROS1 rearrangements. Because a companion diagnostic test has not been approved for ROS1, clinicians should use an appropriately validated test to detect ROS1. Alectinib and ceritinib are not effective in patients with ROS1 rearrangements whose disease becomes resistant to crizotinib. Studies are ongoing regarding new agents for patients with ROS1 rearrangements whose disease becomes resistant to crizotinib. 2017第1版更新，NCCN小组将ROS1检测的推荐移到主要工作步骤中（同时删除了推荐ROS1检测的脚注），根据克唑替尼对ROS1重排患者有效的数据和最近FDA的批准，增加了一个新的ROS1工作步骤，并增加了ROS1分子诊断研究的新章节（见NSCLC NCCN指南中的病理检查原则）。与ALK重排检测相似，ROS1也用FISH检测。NGS（新一代测序技术）也可用来评估是否存在ROS1重排，如果该平台已针对检测ROS1重排适当设计并验证。因为伴随诊断检查尚未批准ROS1，所以临床医生应该用适当的验证检测来测试ROS1。阿雷替尼和色瑞替尼对克唑替尼耐药的ROS1重排患者无效。治疗克唑替尼耐药的ROS1重排患者的新药研究正在进行中。

KRAS Mutations KRAS突变

Data suggest that approximately 25% of patients with adenocarcinomas in a North American population have KRAS mutations; KRAS is the most common mutation. KRAS mutation prevalence is associated with cigarette smoking. Patients with KRAS mutations appear to have a shorter survival than patients with wild-type KRAS; therefore, KRAS mutations are prognostic biomarkers. KRAS mutational status is also predictive of lack of therapeutic efficacy with EGFR-TKIs; however, it does not appear to affect chemotherapeutic efficacy. KRAS mutations do not generally overlap with EGFR mutations, ALK rearrangements, or ROS1 rearrangements. Therefore, KRAS testing may identify patients who may not benefit from further molecular testing. Targeted therapy is not currently available for patients with KRAS mutations, although immune checkpoint inhibitors appear to be effective; MEK inhibitors are in clinical trials. 数据显示，在北美人群中约25%的腺癌患者有KRAS突变；KRAS是最常见的突变。KRAS突变率与吸烟有关。KRAS突变的患者似乎比野生型KRAS患者生存期短；因此，KRAS突变是预后标志物。KRAS突变状态也预示EGFR-TKIs治疗缺乏疗效；不过，它似乎不影响化疗疗效。KRAS突变与表皮生长因子受体突变一般不重叠,筛选重组或ROS1重组。因此，KRAS检测可识别可能不会受益于进一步分子检测的患者。对于KRAS突变的患者目前没有可用的靶向治疗，尽管免疫检查点抑制剂似乎有效；MEK抑制剂正在进行临床试验。