Original Article

Clinicopathologic Features and Outcomes of Patients With Lung Adenocarcinomas Harboring BRAF Mutations in the Lung Cancer Mutation Consortium Liza C. Villaruz, MD1; Mark A. Socinski, MD1; Shira Abberbock, MS1; Lynne D. Berry, PhD2; Bruce E. Johnson, MD3; David J. Kwiatkowski, MD4; A. John Iafrate, MD5; Marileila Varella-Garcia, PhD6; Wilbur A. Franklin, MD6; D. Ross Camidge, MD6; Lecia V. Sequist, MD5; Eric B. Haura, MD7; Mark Ladanyi, MD8; Brenda F. Kurland, PhD1; Kelly Kugler, BA6; John D. Minna, MD9; Paul A. Bunn, MD6; and Mark G. Kris, MD8

BACKGROUND: The advent of effective targeted therapy for BRAFV600E-mutant lung adenocarcinomas necessitates further exploration of the unique clinical features and behavior of advanced-stage BRAF-mutant lung adenocarcinomas. METHODS: Data were reviewed for patients with advanced lung adenocarcinomas enrolled in the Lung Cancer Mutation Consortium whose tumors underwent testing for mutations in epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), human epidermal growth factor receptor 2 (HER2), AKT1, BRAF, dual-specificity mitogen-activated protein kinase kinase 1 (MEK1), neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit a (PIK3CA); for anaplastic lymphoma kinase (ALK) translocations; and for MET amplification. RESULTS: Twenty-one BRAF mutations were identified in 951 patients with adenocarcinomas (2.2%; 95% confidence interval [CI], 1.4%-3.4%): 17 (81%; 95% CI, 60%-92%) were BRAFV600E mutations, and 4 were non-BRAFV600E mutations. Among the 733 cases tested for all 10 genes, BRAF mutations were more likely to occur than most other genotypic abnormalities in current or former smokers (BRAF vs sensitizing EGFR, 82% vs 36%, mid-P .20). CONCLUSIONS: BRAF mutations occurred in 2.2% of advanced-stage lung adenocarcinomas, were most commonly V600E, and were associated with distinct clinicopathologic features in comparison with other genomic subtypes and with a high mutation rate in more than 1 gene. These findings underscore the importance of comprehensive genomic C 2014 American Cancer Society. profiling in assessing patients with advanced lung adenocarcinomas. Cancer 2015;121:448-56. V KEYWORDS: BRAF, clinicopathologic features, genomic profiling, lung adenocarcinomas, Lung Cancer Mutation Consortium..

INTRODUCTION Recent advances in the treatment of lung cancers have come from the recognition that lung cancers are not a single disease entity but rather are a collection of distinct molecularly driven neoplasms. Lynch et al,1 Paez et al,2 and Pao et al3 first described a subset of patients with lung cancers harboring activating mutations in the epidermal growth factor receptor (EGFR) gene who responded to treatment with EGFR tyrosine kinase inhibitors. This discovery permanently shifted the landscape of lung cancer therapy to a personalized approach based on the molecular alterations of a patient’s tumor; this paradigm is typified not only by targeted therapies for EGFR-mutant lung adenocarcinomas but also by anaplastic lymphoma kinase (ALK) translocation–driven adenocarcinomas of the lung and, more recently, therapeutic advances in lung adenocarcinomas harboring BRAF mutations.3-5 BRAF is a member of the RAF kinase family of serine/threonine protein kinases, which have diverse roles in mediating proliferation and survival. Upon activation by RAS, BRAF phosphorylates dual-specificity mitogen-activated protein kinase kinase (MEK), and this leads to the activation of extracellular signal-regulated kinase (ERK) and the ERK signaling pathway. The most commonly observed mutation in BRAF is the valine (V) to glutamic acid (E) substitution at residue

Corresponding author: Liza C. Villaruz, MD, University of Pittsburgh Cancer Institute, 5150 Centre Avenue, Cancer Pavilion, Room 567, Pittsburgh, PA 15232; Fax: (412) 648-6579; [email protected] 1 University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania; 2Vanderbilt-Ingram Cancer Center, Nashville, Tennessee; 3Dana-Farber Cancer Institute, Boston, Massachusetts; 4Brigham and Women’s Hospital, Boston, Massachusetts; 5Massachusettes General Hospital, Boston, Massachusetts; 6University of Colorado Cancer Center at Denver, Aurora, Colorado; 7H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida; 8Memorial Sloan-Kettering Cancer Center, New York, New York; 9University of Texas Southwestern Medical Center, Dallas, Texas.

DOI: 10.1002/cncr.29042, Received: June 4, 2014; Revised: July 10, 2014; Accepted: July 16, 2014, Published online October 1, 2014 in Wiley Online Library (wileyonlinelibrary.com)

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600 (BRAFV600E), which results in a mutant BRAF protein that no longer requires dimerization for its activity and is constitutively active and transforming in vitro.6,7 Although the BRAFV600E mutation accounts for almost 80% to 90% of all BRAF mutations in melanoma, BRAFV600E mutations have been reported in 50% to 58% of patients with lung cancers, and additional mutations that have a transforming ability in vitro have been identified.8-12 To date, a single-institution series of patients with BRAF-mutant lung cancers of all stages reported a frequency of 3% and an association with either a current or former smoking status.10 In a multi-institutional Italian series of predominantly early-stage surgically resected lung cancers, BRAFV600E mutations were demonstrated in 5% of the patients and were associated with female sex, a never smoking status, and the presence of micropapillary features, an uncommon histologic pattern associated with tumor aggressiveness.11 In this series of patients, BRAFV600E was associated with inferior disease-free survival and overall survival (OS) in comparison with a BRAF wild-type genotype. In contrast, non-V600E mutations occurred exclusively in smokers at similar rates in men and women and were not associated with prognostic differences in comparison with BRAF wild-type tumors. Two BRAF inhibitors, vemurafenib and dabrafenib, have shown clinical activity in metastatic BRAFV600E-mutant lung cancers.5,13,14 A recent phase 2 study of the specific BRAF inhibitor dabrafenib in patients with stage IV BRAFV600E-mutant lung cancers demonstrated an investigator-assessed overall response rate of 54% with durable responses as long as 49 weeks in the first 20 patients.5 This compares favorably with what has previously been seen in metastatic melanoma with vemurafenib.15 The Lung Cancer Mutation Consortium (LCMC) is a 14-institution collaborative effort established in 2009 to assay lung adenocarcinomas for driver genomic alterations in 10 genes to study and treat patients by their molecular subtype.16 With the advent of effective targeted therapy for BRAFV600E-mutant lung adenocarcinomas, there is a need to further explore the unique clinical features and behavior of advanced-stage BRAF-mutant lung adenocarcinomas. The purpose of this study was to delineate the clinicopathologic features and prognosis of BRAF-mutant lung cancers in comparison with other genomic subsets identified through the LCMC. This study marks the first series of advanced and metastatic BRAF-mutant lung adenocarcinomas that have been assessed in the context of comprehensive genomic profiling for 10 different oncogenic drivers, and this allows a unique comparison of a BRAF-mutant cohort of lung adeCancer

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nocarcinoma patients not only with other genomic subsets but also with a subset of patients in whom no oncogenic drivers have been identified. MATERIALS AND METHODS Study Design and Patients

The study population was selected from the cohort of 1007 patients enrolled in the LCMC with confirmed adenocarcinomas. The LCMC study design has been previously described.16 Briefly, the LCMC enrolled patients with stage IV or recurrent adenocarcinomas of the lungs and with a Southwest Oncology Group performance status of 0, 1, or 2. Patients provided written informed consent, and those with adequate tumor tissue for genomic characterization remained eligible. The age, sex, race, cigarette smoking history, metastatic sites, and stage at diagnosis were entered into a secure Web-based database. Sites reported whether or not each patient received therapy directed against a detected driver and the duration of survival. The LCMC was conducted with the approval of each participating sites’ Institutional Review Committee. One patient with advanced BRAF-mutant lung cancer was included in a prior report focusing on BRAF mutations.10 Genomic Analysis

Investigators at the enrolling site or another LCMC site identified genomic changes in Clinical Laboratory Improvement Amendments–certified laboratories with direct sequencing, SNaPshot, or Sequenom-based genotyping methods to detect mutations in EGFR, Kirsten rat sarcoma viral oncogene homolog (KRAS), human epidermal growth factor receptor 2 (HER2), AKT1, BRAF, MEK1, neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit a (PIK3CA). Testing of ALK gene rearrangements and MET amplification was performed with florescence in situ hybridization.17-20 Doubletons were defined as adenocarcinomas harboring oncogenic drivers in 2 different genes. Specimens obtained by surgery, core or fine-needle biopsy, and pleural fluid drainage were acceptable. Submitted slides and blocks were assessed for diagnosis and for the adequacy of tumor samples at the site where testing was performed. In general, 100 cells per slide were required for florescence in situ hybridization and mutational testing. Approximately 200 ng of DNA was needed for SNaPshot, and 120 ng of DNA was needed for Sequenom-based genotyping. LCMC pathologists shared blinded samples, with a positive sample included for all 10 drivers. Mutation information was recorded in a GeneInsight database.21 449

Original Article Statistical Methods

Only patients whose tumors underwent testing for all 10 genes were included in the analysis of patient clinical characteristics. Each genomic group was compared with the BRAF-mutant lung adenocarcinoma group with the Wilcoxon rank-sum test for continuous variables, with the mid-P adjustment to Fisher’s exact test for comparing rates, and with Fisher’s exact test for other categorical variables.22,23 Proportions were reported with the Wilson (score) confidence interval (CI). OS was calculated from the time of metastatic disease diagnosis; patients with missing survival information were excluded. Survival curves were estimated with the Kaplan-Meier method; differences between the survival curves for the BRAF-mutant group and the other groups were evaluated with the log-rank test. A multivariate analysis assessing the effect of covariates on OS was performed with Cox proportional hazards regression. Individual statistical tests were not adjusted for multiple comparisons, and all P values were 2-sided. Statistical analyses were performed with SAS/ STAT version 9.4 (SAS Institute, Cary, NC) and R version 3.0.1 (R Foundation for Statistical Computing, Vienna, Austria). RESULTS Patient Characteristics

One-thousand five-hundred thirty-seven patients were enrolled between 2009 and 2012, and 1102 were eligible. Among the 1007 patients with confirmed adenocarcinomas, 951 patient tumors were tested for BRAF mutations, and 21 BRAF mutations (2.2%; 95% CI, 1.4%-3.4%) were identified. Characteristics of the 733 patients whose tumors underwent testing for all 10 genes are summarized in Table 1. On average, patients whose tumors harbored BRAF mutations (median, 65 years) were older than patients with ALK rearrangements (median, 54 years; P 5 .002). Significant differences were seen in sex between patients with BRAF mutations and patients with sensitizing EGFR mutations (exon 19 deletion, L858R, L858Q and G719X; 50% of patients with BRAF mutations were female, whereas 76% of patients with sensitizing EGFR mutations were; mid-P 5 .02.) Race, stage at diagnosis, and histologic subtype were not found to differ between patients with BRAF mutations and those with other genomic abnormalities or with no identified oncogenic driver. Patients with BRAF-mutant tumors were more likely to be current or former smokers than those whose tumors harbored most other genotypic abnormalities (BRAF vs sensitizing EGFR, 82% vs 36%, mid-P < .001; BRAF vs 450

ALK, 39%, mid-P 5 .003; BRAF vs other mutations, 49%, mid-P 5 .02; BRAF vs doubletons, 46%, midP 5 .04.) The proportion of current or former smokers did not appear to differ between patients with BRAF mutations and patients with no identified oncogenic drivers (74%, mid-P 5 .66), whereas the proportion of former or current smokers was greater among patients with KRAS-mutant tumors (95%, mid-P 5 .04). Although the smoking history distribution of patients with BRAF-mutant tumors was similar to that of patients whose tumors had no oncogenic driver (Table 1), ALK rearrangements and EGFR mutations appeared disproportionately in never smokers. We, therefore, treated the smoking history as a potential confounding variable for the multivariate logistic regression assessing trends seen in the univariate analysis. When we controlled for the smoking history, a higher patient age was still associated with tumor BRAF mutations in comparison with tumor ALK rearrangements (odds ratio, 1.09; P 5 .01), and male patient sex was still associated with tumor BRAF mutations in comparison with sensitizing EGFR mutations (odds ratio, 3.41; P 5 .03). BRAF Mutation Genotypes

Four BRAF mutation genotypes were identified. Twentyone BRAF mutations were identified in 951 samples: 17 (81%; 95% CI, 60%-92%) were BRAFV600E mutations, and 4 were non-BRAFV600E mutations (Table 2). The non-BRAFV600E mutations were BRAFG469A (2 or 10%), BRAFG469V (1 or 5%), and BRAFG466R (1 or 5%). No patients with a BRAF mutation had a concomitant mutation in EGFR, HER2, KRAS, AKT1, MEK1, or NRAS or MET amplification. Three tumors with BRAFV600E mutations had a second genomic abnormality in another gene: 2 tumors had PIK3CA mutations (PIK3CAE542K and PIK3CAE545K), and 1 tumor harbored a concurrent ALK translocation. Among the 733 cases tested for all 10 genes, the double-mutation rate for patients with BRAF mutations was 16% (3/19; 95% CI, 6%-38%), which was higher than the double-mutation rate for patients with other genomic abnormalities (5% or 21/447; 95% CI, 3%-7%; mid-P 5 .045). Patients in whom no oncogenic driver was identified were excluded from this analysis of the rate of double mutations. Three patients received targeted therapy with a selective inhibitor of the MEK1/2 kinases, selumetinib, and 1 patient with a co-occurring ALK translocation received crizotinib. Clinical Outcomes

Patients with BRAF-mutant tumors had the longest median OS (56 months; 9/15 patients were censored Cancer

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TABLE 1. Patient Characteristics (n 5 733)a Single Mutation

Age at enrollment (y), median (range) P (Wilcoxon rank sum)c Sex, n (%) Female Male Mid-P Race, n (%) White Black Asian American Indian or Alaska Native Native Hawaiian or other Pacific Islander Not reported Mid-P Smoking, n (%) Never Former Current Not reported Mid-Pd Lung cancer stage at diagnosis, n (%) IA IB IIA IIB IIIA IIIB IV Not reported P (Wilcoxon rank sum) Histological subtype, n (%) Acinar Lepidic Micropapillary Papillary Solid Not reported Mid-Pe Metastatic site in brain, n (%) Yes No Not reported Mid-P

BRAF Mutation (n 5 16)

EGFR (Sensitizing) Mutation (n 5 122)

KRAS Mutation (n 5 182)

ALK Rearrangement (n 5 57)

Other Mutation (n 5 65)b

No Oncogenic Driver Identified (n 5 267)

Doubleton (n 5 24)b

65 (42-80)

63 (31-86)

65 (26-86)

54 (23-76)

60 (28-84)

64 (18-93)

62 (41-78)

.41

.99

.002

.32

.46

.22

8 (50) 8 (50)

93 (76) 29 (24) .02

115 (63) 67 (37) .24

35 (61) 22 (39) .49

34 (52) 31 (48) .89

140 (52) 127 (48) .90

15 (63) 9 (38) .43

14 (88) 1 (6) 1 (6) —

93 (81) 6 (5) 16 (14) —

166 (93) 6 (3) 4 (2) 1 (1)

50 (94) 1 (2) 2 (4) —

48 (77) 8 (13) 6 (10) —

235 (92) 15 (6) 6 (2) —

20 (91) — 2 (9) —





1 (1)











7 (6) .76

4 (2) .38

4 (7) .33

3 (5) .88

11 (4) .39

2 (8) .75

3 (19) 11 (69) 2 (13) —

79 (65) 41 (34) 2 (2) — .20; Fig. 1). After we controlled for established factors (age, sex, smoking history, and use of targeted therapy) with Cox proportional hazards models, there were no observed differences in OS between patients with a BRAF mutation and patients with other single oncogenic drivers or patients in whom no oncogenic driver was identified (pairwise likelihood ratio tests, P  .10). However, patients with doubletons were found to have shorter OS in comparison with patients with single BRAF mutations (hazard ratio, 4.9; 95% CI, 1.5-16.1; P 5 .006) DISCUSSION Our study represents the largest survey to date of advanced BRAF-mutant lung adenocarcinomas assessed in the context of comprehensive multiplexed genotyping 452

for 10 different oncogenic drivers, and it allows an unprecedented comparison of BRAF-mutant lung adenocarcinomas not only with other genomic subsets but also with a subset in which no oncogenic driver was identified (Table 3). We report BRAF mutations occurring at a frequency of 2.2%, and this is similar to prior series of patients with BRAF-mutant lung cancers, which have reported frequencies of 3% to 5% (Table 3).10,12 Our findings indicate that BRAF mutations in lung adenocarcinomas are associated with unique clinicopathologic features in comparison with other genomic subtypes. Although BRAF mutations occur with an age distribution similar to that of patients with sensitizing EGFR and KRAS mutations, patients with ALK rearrangements are significantly younger. BRAF mutations occur equally in men and women, in contrast to sensitizing EGFR mutations, which occur more frequently in women. Similar to other series of patients with BRAF-mutant lung adenocarcinomas, the LCMC represents a predominantly white population.10-12 According to the small number of nonwhite patients in our study, there is no difference in the distribution of patients with BRAF mutations with respect to race in comparison with other genomic subsets; however, larger and more racially diverse cohorts of patients Cancer

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Figure 1. Kaplan-Meier curves for OS from the time of metastatic disease diagnosis for patients with BRAF-mutant lung adenocarcinomas with pairwise comparisons with patients with adenocarcinomas harboring other genomic abnormalities. Patients with missing survival information were excluded. ALK indicates anaplastic lymphoma kinase; CI, confidence interval; EGFR, epidermal growth factor receptor; KRAS, Kirsten rat sarcoma viral oncogene homolog; NM, not met; OS, overall survival.

are needed to delineate the prevalence of BRAF-mutant lung adenocarcinomas in different ethnic groups. BRAF mutations are more likely in former or current smokers; this is in marked contrast to patients with sensitizing EGFR mutations and ALK translocations, who tend to be never smokers. Paik et al10 compared patients with BRAF-mutant lung adenocarcinomas of all stages with patients with lung adenocarcinomas harboring EGFR mutations, KRAS mutations, and ALK translocations; their series also demonstrated an association between BRAF mutations and a current or former smoking history (Table 3). Marchetti et al11 compared the clinical characteristics of patients with BRAF-mutant lung adenocarcinomas and patients with BRAF wild-type lung adenocarcinomas in a predominantly surgical series of patients and found that V600E mutations were more common in never smokers, whereas non-V600E mutations were found exclusively in current or former smokers. Cancer

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In the current series, there were too few patients with nonV600E mutations to perform an analysis of the smoking history among BRAF mutation subtypes. The spectra of mutations in both p53 and KRAS differ significantly between smokers and nonsmokers, with a clear predilection for G!T transversion mutations in smokers versus nonsmokers.19,24,25 In the current series, the spectrum of BRAF mutations was limited to transversion mutations (predominantly the V600E T!A transversion mutation), supporting the role of tobacco exposure in BRAF mutagenesis in lung cancers. The LCMC demonstrated a proportion of V600E mutations (81%) in lung adenocarcinomas comparable to that in melanoma, in which V600E mutations account for 80% to 90% of the BRAF mutations.8,9 Prior series of BRAF-mutant lung adenocarcinomas have demonstrated a significantly lower proportion of V600E mutations in lung adenocarcinomas (between 50% and 58% of all 453

Original Article TABLE 3. Summary of Clinicopathologic Features of BRAF-Mutant Lung Adenocarcinomas From This Series and Previous Series Paik et al10 (2011) Setting Patients, n BRAF mutant, n (%) Stage, n (%)

Marchetti et al11 (2011)

Cardarella et al12 (2013)a

Single US institution 697 18 (3) Stages I-IIIA: 8 (44) Stages IIIB-IV: 10 (56)b EGFR-mutant, KRAS-mutant, and ALK-rearranged lung adenocarcinomas No differences in age or sex; BRAF mutations more likely in whites

Multiple Italian institutions 739 36 (5) Stages I-III: 34 (94) Stage IV: 2 (6) BRAF wild-type lung adenocarcinomas

Associated smoking status

BRAF mutations more likely in current/former smokers

V600E more common in never smokers; non-V600E mutations found exclusively in current/former smokers

No differences in smoking history

BRAF genotypes, n (%) Associated clinical outcome

V600E: 9 (50) Non-V600E: 9 (50) No OS differences in stage IIIB/IV patients

V600E: 21 (58) Non-V600E: 15 (42) V600E-mutant tumors associated with inferior DFS and OS postoperatively

V600E: 18 (50) Non-V600E: 18 (50) No OS differences

Comparator group

Associated clinical features

V600E mutations more common in females

Single US institution 883 36 (4) Stages I-III: 11 (31) Stage IV: 25 (69) BRAF/EGFR/KRAS/ALK wild-type lung adenocarcinomas No differences in age or sex

Current Series Multiple US institutions 951 21 (2) Stage IV: 21 (100)b Patients with known genotype for 10 oncogenic drivers Differences in age between patients with ALK rearrangements and in sex between patients with EGFR mutations BRAF mutations more likely in current/former smokers in comparison with EGFR, ALK, and other genomic subgroups V600E: 17 (81) Non-V600E: 4 (19) No OS differences

Abbreviations: ALK, anaplastic lymphoma kinase; DFS, disease-free survival; EGFR, epidermal growth factor receptor; KRAS, Kirsten rat sarcoma viral oncogene homolog; OS, overall survival. a Two patients with non–small cell lung cancer not otherwise specified. b One patient with advanced BRAF-mutant lung cancer in Paik et al’s series is included in the current series.

BRAF mutations).10-12 The difference in the frequencies of V600E mutations between the LCMC and other series may be due in part to the unique clinical characteristics of patients enrolled in the LCMC; the LCMC included a high proportion of never smokers (32% of the patients who underwent genotyping for all 10 oncogenic drivers). All patients enrolled in the LCMC were at an advanced stage at the time of study enrollment, whereas 31% to 44% of the patients in the series by Paik et al10 and Cardarella et al12 were stage I to III, and virtually all the patients in Marchetti et al’s series11 had surgically resectable disease (Table 3). Delineating the relative frequency of BRAF mutation subtypes in stage IV adenocarcinomas of the lungs is paramount because the second-generation RAF inhibitors, vemurafenib and dabrafenib, have specific activity against the V600E-mutant kinase, whereas preclinical data for lung cancer cell lines harboring nonV600E mutations indicate that the activity of specific V600E inhibitors is nil.5,13,14,26 The prevalence of V600E mutations in the LCMC suggests that a higher proportion of patients with advanced-stage disease may benefit from currently available V600E inhibitors than previously thought. These findings may be tempered by differences in genotyping practices among institutions’ targeted mutation profiles. 454

The double-mutation rate among patients with BRAF mutations was 16%, whereas it was 5% in patients with other oncogenic drivers. The co-occurrence of BRAF mutations with PIK3CA mutations, EGFR mutations, KRAS mutations, and ALK translocations has previously been described in lung cancers, including 2 patients in the series by Marchetti et al with concurrent BRAFV600E mutations and EGFR mutations and 1 patient with a BRAFV600E mutation and a PIK3CA mutation and 2 patients with BRAFG464 mutations and KRAS mutations in the series by Cardarella et al.11,12,27-29 This underscores the role of multiplexed genotyping because more than 1 actionable oncogenic driver may exist within the same patient. It is interesting how the presence of 2 oncogenic drivers leads to a distinct clinical behavior and, more importantly, how targeted therapies aimed at multiple oncogenic drivers should be sequenced or combined. In our series, patients with alterations in more than 1 oncogenic driver (doubletons) were found to have inferior OS in comparison with patients with single BRAF mutations. In a mutational analysis of microdissected melanoma and nevus samples, BRAF mutations were unexpectedly observed in 82% of nevi, and this suggests that BRAF mutations, though a critical step in the initiation of melanocytic Cancer

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neoplasia, are in some cases insufficient for melanoma tumorigenesis.9 This raises the possibility that in tumors in which 2 genomic abnormalities are present, BRAF mutations may not be the predominant oncogenic driver. We have demonstrated that patients with BRAF mutations do not differ in survival from patients harboring other oncogenic drivers or patients with no identified oncogenic driver. This concurs with prior series of BRAF-mutant lung adenocarcinomas with the exception of the predominantly surgical series of BRAF-mutant lung adenocarcinomas by Marchetti et al,11 who found that V600E mutations were associated with inferior disease-free survival and OS in the postoperative setting (Table 3). The LCMC suggests that the natural history of patients with advanced BRAF-mutant lung adenocarcinomas compares favorably with that of patients with EGFR mutations and ALK translocations. A small proportion of patients with BRAF-mutant tumors received targeted therapy, and it will be interesting to see whether targeted agents ultimately alter the natural history of these tumors analogously to ALK inhibitors in ALK-rearranged disease.30 In conclusion, we have demonstrated that BRAF mutations occur in 2.2% of advanced-stage lung adenocarcinomas, are most commonly V600E mutations, and are associated with distinct clinicopathologic features in comparison with other genomic subtypes and with a high mutation rate in more than 1 gene. This has important therapeutic implications because of the marked clinical activity of the specific inhibitor, dabrafenib, in BRAF-mutant lung adenocarcinomas, and it underscores the importance of comprehensive genomic profiling in assessing patients with advanced lung adenocarcinomas. FUNDING SUPPORT This study was supported by a grant from the National Institutes of Health through the National Cancer Institute (HSS NIH NCI 1RC2CA148394-010). This project used the University of Pittsburgh Cancer Institute Biostatistics Facility, which is supported in part by award P30CA047904.

CONFLICT OF INTEREST DISCLOSURES Bruce E. Johnson has been paid as an expert witness for Genentech for a drug produced for EGFR-mutant lung cancer, he is a shareholder and consultant for the KEW Group (a company that provides advice and genomic testing for patients with cancer), and he receives postmarketing royalties for EGFR mutation testing from the DanaFarber Cancer Institute. David J. Kwiatkowski has been a consultant for Novartis. A. John Iafrate reports personal fees from BioReference Laboratories during the conduct of the study and personal fees from Chugai Pharmaceuticals, Constellation Pharmaceuticals, and Enzymatics outside the submitted work; in addition, he has a preliminary patent for SNaPshot technology licensed to BioReference Laborato-

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ries. Lecia V. Sequist has been an uncompensated consultant for Clovis, Boehringer Ingelheim, AstraZeneca, Novartis, Genentech, Merrimack, and Taiho outside the submitted work. Brenda F. Kurland reports a grant from Merck (3% salary support for an investigator-initiated clinical trial); honoraria and travel expenses from the University of Pennsylvania, the American Association for Cancer Research/American Society of Clinical Oncology, the Radiological Society of North America, and Komen; a Data and Safety Monitoring Board honorarium from the National Institutes of Health; and travel expenses from the Eastern Cooperative Oncology Group/American College of Radiology Imaging Network outside the submitted work. Paul A. Bunn has served as a consultant for Amgen, Astellas, AstraZeneca, Bayer, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Daiichi Sankyo, Eisai, GlaxoSmithKline, Eli Lilly, Merck, Merck Serono, Merrimack, Myriad Genetics, Pfizer, Roche/Genentech, Sanofi, and Synta.

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February 1, 2015

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Clinicopathologic features and outcomes of patients with lung adenocarcinomas harboring BRAF mutations in the Lung Cancer Mutation Consortium.

The advent of effective targeted therapy for BRAF(V600E) -mutant lung adenocarcinomas necessitates further exploration of the unique clinical features...
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