Lung cancer in never-smoker Asian females is driven by oncogenic mutations,most often involving EGFR

The aim of this study was to determine the distribution of known oncogenic driver mutations in female never-smoker Asian patients with lung adenocarcinoma. We analyzed 214 mutations across 26 lung cancer-associated genes and three fusion genes using the MassARRAY® LungCarta Panel and the ALK, ROS1, and RET fusion assays in 198 consecutively resected lung adenocarcinomas from never-smoker females at a single institution. EGFR mutation, which was the most frequent driver gene mutation, was detected in 124 (63%) cases. Mutation of ALK, KRAS, PIK3CA, ERBB2, BRAF, ROS1, and RET genesoccurred in 7%, 4%, 2.5%, 1.5%, 1%, 1%, and 1% of cases, respectively. Thus, 79% of lung adenocarcinomas from never-smoker females harbored well-known oncogenic mutations. Mucinous adenocarcinomas tended to have a lower frequency of known driver gene mutations than other histologic subtypes. EGFR mutation was associated with older age and a predominantly acinar pattern, while ALK rearrangement was associated with younger age and a predominantly solid pattern. Lung cancer in never-smoker Asian females is a distinct entity, with the majority of these cancers developing from oncogenic mutations.     

Expression Profiling of Driver Genes in Female Never-smokers With Non-adenocarcinoma Non–small-cell Lung Cancer in China

BackgroundAlthough smoking is a primary cause of lung cancer, females are overrepresented among never-smokers with the disease. The mutational landscape of adenocarcinoma in never-smoking females has been extensively profiled; however, there is little knowledge about genomic alterations in non-adenocarcinoma non–small-cell lung cancer (NA-NSCLC). In the study, we reviewed the status of oncogenic drivers of NA-NSCLC in these populations.Materials and MethodsComprehensive genomic profiling was performed on DNA extracted from formalin-fixed, paraffin-embedded sections of 52 NA-NSCLC tissues, including 35 squamous cell carcinomas (SQCCs), 11 adenosquamous carcinomas, 5 pulmonary sarcomatoid carcinoma, and 1 large cell carcinoma by next-generation sequencing within a panel of 68 cancer-related genes.ResultsMutations of the common oncogenic drivers (EGFR, KRAS, ALK, ROS1, MET, RET, and ERBB2) occurred in 61.5% of cases. The frequency of well-established targets (EGFR and ALK), new targets without widely available therapies (MET and ERBB2), and potentially actionable targets (RET and DDR2) in SQCCs of female never-smokers was significantly higher than that in The Cancer Genome Atlas dataset. There were 31%, 82%, and 80% of cases with SQCC, adenosquamous carcinoma, and pulmonary sarcomatoid carcinoma, respectively, harboring at least one of the following targets: EGFR, ALK, ERBB2, and MET. Approximately 78% (7/9) of the patients responded to various targeted treatments.ConclusionFemale never-smokers with NA-NSCLC in this study had a high frequency of currently known or potentially actionable oncogenic alterations and could benefit from targeted therapy. Our study also provides evidence for the recommendation of molecular analysis in never-smoking female SQCC.     

Small-Cell Lung Cancer Transformation as a Mechanism of Resistance to Pralsetinib in RET-Rearranged Lung Adenocarcinoma: A Case Report

The majority of resistance to Rearranged during transfection (RET)-specific tyrosine kinase inhibitors (TKI) described in RET-rearranged non-small cell lung cancer (NSCLC) patients are driven by RET-independent mechanisms. We provide the first case report of a RET-rearranged lung adenocarcinoma (LUAD) transformation into small-cell lung cancer (SCLC) as a mechanism of acquired resistance to pralsetinib. A 43-year-old patient presented with a RET-rearranged LUAD revealed by pleural effusion. After 14 months of response to pralsetinib, biopsy of a progressive pleural lesion found a phenotypic transformation into SCLC. Molecular analysis identified the same RET fusion and TP53 mutation in both primary adenocarcinoma and recurrence as SCLC. The patient achieved partial response after switch to carboplatin and etoposide chemotherapy and presented with progression disease after 6 months. Histological transformation could be a mechanism of resistance to RET-TKIs and rebiopsy should be considered to adapt subsequent treatment.     

Clinical outcomes with pemetrexed-based systemic therapies in RET-rearranged lung cancers

BackgroundRET rearrangements are targetable, oncogenic lung cancer drivers. While previous series have shown durable clinical benefit with pemetrexed-based therapies in ALK- and ROS1-rearranged lung cancers, the benefits of pemetrexed-based treatments in patients with RET-rearranged lung cancers relative to other genomic subsets have not previously been explored.Patients and methodsA retrospective review of patients with pathologically confirmed stage IIIB/IV lung adenocarcinomas and evidence of a RET, ROS1, or ALK rearrangement, or a KRAS mutation was conducted. Patients were eligible if they received treatment with pemetrexed alone or in combination. The primary outcome of progression-free survival (PFS), and secondary outcomes of overall response rate (ORR, RECIST v1.1), time to progression (TTP), and time to treatment discontinuation were compared between RET-rearranged and groups of ROS1-rearranged, ALK-rearranged, and KRAS-mutant lung cancers.ResultsWe evaluated 104 patients. Patients with RET-rearranged lung cancers (n = 18) had a median PFS of 19 months [95% confidence interval (CI) 12–not reached (NR)] that was comparable with patients with ROS1- (23 months, 95% CI 14–NR, n = 10) and ALK-rearranged (19 months, 95% CI 15–36, n = 36) lung cancers, and significantly improved compared with patients with KRAS-mutant lung cancers (6 months, 95% CI 5–9, P < 0.001, n = 40). ORR (45%), median TTP (20 months, 95% CI 17–NR), and median time to treatment discontinuation (21 months, 95% CI 6–NR) in patients with RET-rearranged lung cancers were not significantly different compared with patients with ALK- and ROS1-rearranged lung cancers, and improved compared with patients with KRAS-mutant lung cancers.ConclusionDurable benefits with pemetrexed-based therapies in RET-rearranged lung cancers are comparable with ALK- and ROS1-rearranged lung cancers. When selecting therapies for patients with RET-rearranged lung cancers, pemetrexed-containing regimens should be considered.     

Frequent EGFR Mutations and Better Prognosis in Positron Emission Tomography-Negative,Solid-Type Lung Cancer

BackgroundThe differential diagnosis of a solitary solid-type lung nodule is diverse. 18F-fluorodeoxyglucose positron emission tomography (PET) has a high sensitivity in the diagnosis of solid-type lung cancers; however, PET-negative, solid-type lung cancers are rarely observed. In this study, we analyzed the clinical/genetic features and prognosis of PET-negative, solid-type lung cancers.Patients and MethodsBetween January 2007 and February 2020, 709 patients with solid-type lung cancers (tumor size ≥2.0 cm) underwent pulmonary resection. Clinical, genetic, and prognostic features were evaluated in 27 patients (3.8%) with tumors showing negative PET results defined as SUVmax <2.0.ResultsAll 27 patients had lung adenocarcinoma; 23 had invasive adenocarcinomas and 4 had invasive mucinous adenocarcinomas. The PET-negative group showed high frequencies of females and never-smokers. Recurrence-free survival was significantly better in the PET-negative group compared with PET-positive counterparts extracted using propensity score matching from patients who underwent pulmonary resection during the same period (P = .0052). Furthermore, 83% of PET-negative, solid-type invasive lung adenocarcinoma patients harbored EGFR mutation, which was significantly higher than that of PET-positive, solid-type invasive lung adenocarcinoma patients (38%, n = 225) who received EGFR mutation testing in our cohort (P < .0001). PET-negative, solid-type lung adenocarcinoma patients with EGFR mutations had significantly better recurrence-free survival compared with PET-positive, solid-type lung adenocarcinoma patients with EGFR mutations extracted using propensity score matching (P = .0030).ConclusionPET-negative, solid-type lung cancers are characterized with a high incidence of EGFR mutation and a better prognosis compared with PET-positive, solid-type lung cancer.     

Epidermal growth factor receptor mutation status in pulmonary adenocarcinoma: Multi-institutional data discussion at national conference of “Lung Cancer Management in Indian context”

The presence of activating mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) gene in adenocarcinomas of lung confers sensitivity to tyrosine kinase inhibitor therapy. The prevalence of EGFR mutations varies among different ethnicities and demographic profile. This multi-institutional data was compiled to determine the EGFR mutation status in Indians patients with lung adenocarcinoma. Cohorts represented by 4 tertiary care hospitals participated in data discussion at a national conference entitled as ‘Lung Cancer Management in Indian Context’. The clinicopathologic data and EGFR mutation rate in the patients of lung adenocarcinoma screened in these cohorts were collected and analyzed. The sample types included both surgical and cytological specimens. A variety of methods were used including immunohistochemistry, polymerase chain reaction, Sanger sequencing and next generation sequencing. A total of 3436 cases of treatment naïve lung adenocarcinoma were tested for EGFR mutations. The overall frequency of EGFR mutations observed was 30.03%. The most common baseline mutation detected was exon 19 deletion followed by L858R point mutation in exon 21. Dual mutations were observed in 6.5% of cases and were predominantly combinations of exon 19 deletion and T790M point mutation in exon 20. Incidence of EGFR mutations was higher among females and non-smokers diagnosed with lung adenocarcinomas. The most common histology in EGFR mutant cases was acinar predominant adenocarcinomas. With nearly one-third of Indian patients with lung adenocarcinoma harboring EGFR mutations, routine testing for these mutations is important to get the benefit of targeted therapy.     

融合基因阳性肺腺癌的病理组织学特征及与砂粒体的相关性研究

背景与目的：间变性淋巴瘤激酶(anaplastic lymphoma kinase,ALK)、c-ros原癌基因1酪氨酸激酶(c-ros oncogene 1 receptor tyrosine kinase,ROS1)和RET融合基因被陆续证实为肺腺癌的驱动基因突变,并可在靶向治疗中获益。该研究旨在阐述融合基因阳性肺腺癌病理组织学特征,并探讨砂粒体与融合基因阳性肺腺癌的相关性。方法：收集复旦大学附属肿瘤医院原发肺腺癌患者手术切除新鲜标本和石蜡固定标本,检测肺腺癌标本中表皮生长因子受体(epidermal growth factor receptor,EGFR)、鼠类肉瘤病毒癌基因(Kirsten rat sarcoma viral oncogene,K-ras)、ALK、RET和ROS1基因突变状态。选取融合基因阳性肺腺癌病例44例(9例ROS1阳性,20例K-ras阳性,15例RET阳性)和融合基因阴性肺腺癌111例(20例EGFR突变,20例K-ras突变,71例未检测出基因突变)用于本项研究。根据2015年世界卫生组织(World Health Organization,WHO)肺腺癌新分类评估融合基因组与无融合基因组的病理组织学形态特征,并观察肺腺癌组织中砂粒体的数量及其分布的特征,并探讨砂粒体与融合基因阳性肺腺癌的相关性。结果：融合基因组中主要组织学亚型为腺泡状亚型(19/44,43.2%)和实体亚型(13/44,29.5%),无融合基因组主要组织学亚型为腺泡状亚型(50/111,45.0%)。实体亚型更多见于融合基因组,但两组间主要组织学亚型差异无统计学意义(P=0.060)。含印戒细胞成分、微乳头结构、黏液筛状结构及细胞外黏液分泌在融合基因组中阳性率均显著高于无融合基因组(P=0.000,P=0.044,P=0.000,P=0.010)。砂粒体在融合基因组阳性率显著高于无融合基因组(P=0.000),并且砂粒体与微乳头及黏液筛状结构具有显著相关性(P=0.000)。结论：实体亚型及腺泡状亚型常见于融合基因阳性肺腺癌。砂粒体、微乳头、细胞外黏液分泌、黏液筛状结构及含印戒细胞成分等特征性组织学形态与融合基因阳性肺腺癌密切相关,并且砂粒体与微乳头结构和(或)黏液筛状结构往往同时存在。通过对肺腺癌的特征性形态学观察对肺腺癌基因检测的优先性筛选具有指导意义。     

Association between vascular-poor area of primary tumors and epidermal growth factor receptor gene status in advanced lung adenocarcinoma

Mutation of the epidermal growth factor receptor gene (EGFR mutation) is a very important marker in the treatment for non-small cell lung cancer. Since signaling from this receptor induces tumor-associated angiogenesis, we hypothesized that lung cancers with EGFR mutations tend to develop locally with increased angiogenesis. Thus, the association between vascular-poor area of primary tumors and EGFR status was retrospectively investigated in advanced lung adenocarcinomas. To assess vascular-poor area, contrast-enhanced computed tomography scans taken before initial treatment for lung cancer were analyzed, together with primary tumor location (peripheral or central) and size. We analyzed 178 patients with advanced lung adenocarcinoma. EGFR mutations were detected in 95 of the 178 patients (53.4?%). EGFR mutation was found to be significantly related to women (P?=?0.0070), never-smokers (P?<?0.0001), and tumors without vascular-poor area (P?<?0.0001). Based on a multivariate analysis, presence of EGFR mutations was independently associated with never-smokers (P?=?0.0046), lack of vascular-poor area (P?=?0.0001), and tumor size >30?mm (P?=?0.0080). EGFR mutations were found in 41 of 51 never-smokers without vascular-poor area (80.4?%), 19 of 36 never-smokers with vascular-poor area (52.8?%), 19 of 37 current or former-smokers without vascular-poor area (51.4?%), and 16 of 54 current or former-smokers with vascular-poor area (29.6?%). This study showed an association between vascular-poor area of primary tumors and EGFR status. As a consequence, evaluation using a combination of smoking status and vascular-poor area allows us to predict presence of EGFR mutations at a high frequency.     

Lung cancers unrelated to smoking: characterized by single oncogene addiction?

Lung cancer is a major cause of cancer-related mortality worldwide. Currently, adenocarcinoma is its most common histological subtype in many countries. In contrast with small cell lung cancer or squamous cell carcinoma, lung adenocarcinoma often arises in never-smokers, especially in East Asian countries, as well as in smokers. Adenocarcinoma in never-smokers is associated with a lower incidence of genetic alterations (i.e., somatic mutations, loss of heterozygosity, and methylation) than in smokers. In addition, most adenocarcinomas in never-smokers harbor one of the proto-oncogene aberrations that occur in a mutually exclusive manner (EGFR mutation, KRAS mutation, HER2 mutations, or ALK translocation). It is of note that the proliferation and survival of lung cancer cells that harbor one of these oncogenic aberrations depend on the signaling from each aberrantly activated oncoprotein (oncogene addiction). Therefore, most adenocarcinomas in never-smokers can be effectively treated by molecularly targeted drugs that inhibit each oncoprotein. Moreover, from a pathological aspect, lung adenocarcinoma in never-smokers is characterized by terminal respiratory unit-type adenocarcinoma and a particular gene expression profile. Finally, epidemiological analyses have identified many candidate causes of lung cancer in never-smokers (genetic, environmental, and hormonal factors). The elucidation of the particular features of lung cancer unrelated to smoking and the development of new therapeutic modalities may reduce the mortality from lung cancers in the future.     

Detection of Novel NRG1, EGFR,and MET Fusions in Lung Adenocarcinomas in the Chinese Population

IntroductionMultiple oncogene fusions beyond ALK receptor tyrosine kinase (ALK), RET, and ROS1 fusion has been described in lung cancer, especially in lung adenocarcinomas without common oncogenic mutations. Molecular inhibitors have been developed and proved effective for patients whose tumors harbor these novel alterations.MethodsA consecutive series of surgically resected lung adenocarcinomas were collected and profiled using an enrichment strategy to detect nine common oncogenic driver mutations and fusions concerning EGFR, KRAS, HER2, BRAF, MET, ALK, RET, ROS1, and FGFR. Driver-negative cases were further analyzed by a comprehensive RNA-based next-generation sequencing (NGS) fusion assay for novel fusions.ResultsIn total, we profiled 1681 lung adenocarcinomas, among which 255 cases were common driver–negative. One hundred seventy-seven cases had sufficient tissue for NGS fusions screening, which identified eight novel fusions. NRG1 fusions occurred in 0.36% of all lung adenocarcinoma cases (6 of 1681 cases), including 4 CD74-NRG1–positive cases, 1 RBPMS-NRG1–positive case, and 1 novel ITGB1-NRG1–positive case. Furthermore, another 2 novel fusions were also detected, including 1 EGFR-SHC1 fusion and 1 CD47-MET fusion, both of which were in-frame and retained the functional domain of the corresponding kinases. No fusion event was detected for NTRK, KRAS, BRAF or HER2 genes in this cohort. Detailed clinicopathologic data showed that invasive mucous adenocarcinoma (three of eight cases) and acinar-predominant adenocarcinoma (three of eight cases) were the most prevalent pathologic subtypes among novel fusions.ConclusionsFusions affecting NRG1, EGFR, and MET were detected in 0.48% of unselected lung adenocarcinomas, and NRG1 fusions ranked the most prevalent fusions in common driver-negative lung adenocarcinomas from Chinese population. RNA-based NGS fusion assay was an optional method for screening actionable fusions in common driver-negative cases.     

Computed Tomography Imaging Features and Distribution of Metastases in ROS1-rearranged Non–Small-cell Lung Cancer

BackgroundROS proto-oncogene 1 (ROS1) rearrangements are a known molecular target in non–small-cell lung cancer (NSCLC). Our goal was to determine whether ROS1-rearranged NSCLC has imaging features and patterns of metastasis, which differ from those of anaplastic lymphoma kinase (ALK)-rearranged or epidermal growth factor receptor (EGFR)-mutant NSCLC.Patients and MethodsWe retrospectively identified patients with metastatic ROS1-rearranged, ALK-rearranged, or EGFR-mutant NSCLC from January 2014 to June 2018 and included those with pretreatment imaging studies available. We assessed the imaging features of the primary tumor and the distribution of metastases in these patients. The Wilcoxon rank-sum test and Fisher exact test were used to compare the imaging features.ResultsWe identified 257 patients (167 women and 90 men; median age, 56 years; range, 19-90 years) with metastatic NSCLC (ROS1, 53; ALK, 87; EGFR, 117). Compared with ALK-rearranged or EGFR-mutant NSCLC, ROS1-rearranged NSCLC was less likely to present with extrathoracic metastases (ROS1, 49%; ALK, 75%; EGFR, 72%; P < .01), including brain metastases (ROS1, 9%; ALK, 25%; EGFR, 40%; P < .04). Compared with EGFR-mutant NSCLC, ROS1-rearranged tumors were more likely to exhibit imaging features of lymphangitic carcinomatosis (ROS1, 42%; EGFR, 12%; P < .01) and less likely to have air bronchograms in the primary tumor (ROS1, 2%; EGFR, 28%; P < .01). ROS1-rearranged tumors were also more likely to present with distant nodal metastases (ROS1, 15%; EGFR, 2%; P < .01) and sclerotic-type bone metastases (ROS1, 17%; EGFR, 6%; P < .01).ConclusionAlthough considerable overlap exists in the imaging features of ROS1-rearranged, ALK-rearranged, and EGFR-mutant NSCLC, we found that ROS1-rearranged NSCLC has certain distinct imaging features and patterns of spread.     

Small-Cell Carcinoma With an Epidermal Growth Factor Receptor Mutation in a Never-Smoker With Gefitinib-Responsive Adenocarcinoma of the Lung

Activating mutations in the epidermal growth factor receptor (EGFR) gene are extremely rare in small-cell lung cancer (SCLC). Here, we present a case of an EGFR-mutant gefitinib-responsive non–small-cell lung cancer (NSCLC) of adenocarcinoma histology occurring in a never-smoker followed by subsequent diagnosis of metastatic SCLC carrying an EGFR mutation. Although gefitinib therapy of the primary NSCLC resulted in disease control for over 3 years, the patient subsequently developed metastatic SCLC to the liver. Epidermal growth factor receptor mutation analysis revealed that the exon 21 L858R activating mutation was present in both the original lung adenocarcinoma and the metastatic SCLC. We hypothesize that SCLC either evolved from the previously diagnosed NSCLC or that both arose from a common precursor. Further comparative molecular analysis of these histologically distinct tumors would be of value to better understand the potential role of EGFR in the pathogenesis of SCLC in never-smokers, and the role of selection for an EGFR-mutant SCLC subclone as an unusual mechanism of acquired resistance to EGFR inhibitors in NSCLC.     

Clinical Impact of Hybrid Capture–Based Next-Generation Sequencing on Changes in Treatment Decisions in Lung Cancer

IntroductionTargeted therapy significantly prolongs survival in lung adenocarcinoma. Current diagnostic guidelines include only EGFR and anaplastic lymphoma receptor tyrosine kinase gene (ALK) testing. Next-generation sequencing (NGS) reveals more actionable genomic alterations than do standard diagnostic methods. Data on the influence of hybrid capture (HC)-based NGS on treatment are limited, and we investigated its impact on treatment decisions and clinical outcomes.MethodsThis retrospective study included patients with advanced lung cancer on whom HC-based NGS was performed between November 2011 and October 2015. Demographic and clinicopathologic characteristics, treatments, and outcome data were collected.ResultsA total of 101 patients were included (median age 63 years [53% females, 45% never-smokers, and 85% with adenocarcinoma]). HC-based NGS was performed upfront and after EGFR/ALK testing yielded negative or inconclusive results in 15% and 85% of patients, respectively. In 51.5% of patients, HC-based NGS was performed before first-line therapy, and in 48.5%, it was performed after treatment failure. HC-based NGS identified clinically actionable genomic alterations in 50% of patients, most frequently in EGFR (18%), Ret proto-oncogene (RET) (9%), ALK (8%), Mesenchymal-epithelial transition factor (MET) receptor tyrosine kinase gene (6%), and erb-b2 receptor tyrosine kinase 2 gene (ERBB2) (5%). In 15 patients, it identified EGFR/ALK aberrations after negative results of prior standard testing. Treatment strategy was changed for 43 patients (42.6%). The overall response rate in these patients was 65% (complete response 14.7%, partial response 50%). Median survival was not reached. Immunotherapy was administered in 33 patients, mostly without an actionable driver, with a presenting disease control rate of 32%, and with an association with tumor mutation burden.ConclusionsHC-based NGS influenced treatment decisions in close to half of the patients with lung adenocarcinoma and was associated with an overall response rate of 65%, which may translate into a survival benefit.     

High Prevalence of Concomitant Oncogene Mutations in Prospectively Identified Patients with ROS1-Positive Metastatic Lung Cancer

ObjectivesChromosomal rearrangements involving ROS1 define a rare entity of lung adenocarcinomas with exquisite sensitivity to molecularly targeted therapy. We report clinical outcomes and genomic findings of patients with ROS1-positive lung cancer who were prospectively identified within a multiplex biomarker profiling program at the West German Cancer Center.MethodsStandardized immunohistochemical (IHC) analysis, fluorescence in situ hybridization (FISH), and hotspot mutation analyses were performed in 1345 patients with advanced cancer, including 805 patients with metastatic lung adenocarcinoma. Clinical and epidemiological data were retrieved from the institutional database.ResultsROS1 positivity by IHC analysis was detected in 25 patients with lung cancer (4.8% of lung adenocarcinomas), including 13 patients (2.5%) with ROS1 FISH positivity with a cutoff of at least 15% of events. Of the ROS1 IHC analysis–positive cases, 36% presented with concomitant oncogenic driver mutations involving EGFR (six cases, five of which were clinically validated by response to EGFR-targeting agents), KRAS (two cases), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha gene (PIK3CA), and BRAF. Three cases initially classified as ROS1 FISH–negative passed the threshold of 15% positive events when repeat biopsies were analyzed at progression. The median overall survival of the ROS1-positive patients (104 months) was significantly superior to that of the 261 patients with EGFR/anaplastic lymphoma kinase/ROS1–negative lung adenocarcinoma (24.4 months, p = 0.044). Interestingly, the overall survival of the 13 ROS1-positive patients with lung cancer from initiation of pemetrexed-based chemotherapy was significantly prolonged when compared with that of 169 pemetrexed-treated patients with EGFR/anaplastic lymphoma kinase/ROS1–negative adenocarcinoma (p = 0.01).ConclusionsROS1-positive metastatic lung adenocarcinomas frequently harbor concomitant oncogenic driver mutations. Levels of ROS1 FISH–positive events are variable over time. This heterogeneity provides additional therapeutic options if discovered by multiplex biomarker testing and repeat biopsies.