Abstract: KRAS is the most common oncogenic driver in lung adenocarcinoma (LUAC). We previously reported that STK11/LKB1 (KL) or TP53 (KP) comutations define distinct subgroups of KRAS-mutant LUAC. Here, we examine the efficacy of PD-1 inhibitors in these subgroups. Objective response rates to PD-1 blockade differed significantly among KL (7.4%), KP (35.7%), and K-only (28.6%) subgroups (P & lt; 0.001) in the Stand Up To Cancer (SU2C) cohort (174 patients) with KRAS-mutant LUAC and in patients treated with nivolumab in the CheckMate-057 phase III trial (0% vs. 57.1% vs. 18.2%; P = 0.047). In the SU2C cohort, KL LUAC exhibited shorter progression-free (P & lt; 0.001) and overall (P = 0.0015) survival compared with KRASMUT;STK11/LKB1WT LUAC. Among 924 LUACs, STK11/LKB1 alterations were the only marker significantly associated with PD-L1 negativity in TMBIntermediate/High LUAC. The impact of STK11/LKB1 alterations on clinical outcomes with PD-1/PD-L1 inhibitors extended to PD-L1–positive non–small cell lung cancer. In Kras-mutant murine LUAC models, Stk11/Lkb1 loss promoted PD-1/PD-L1 inhibitor resistance, suggesting a causal role. Our results identify STK11/LKB1 alterations as a major driver of primary resistance to PD-1 blockade in KRAS-mutant LUAC. Significance: This work identifies STK11/LKB1 alterations as the most prevalent genomic driver of primary resistance to PD-1 axis inhibitors in KRAS-mutant lung adenocarcinoma. Genomic profiling may enhance the predictive utility of PD-L1 expression and tumor mutation burden and facilitate establishment of personalized combination immunotherapy approaches for genomically defined LUAC subsets. Cancer Discov; 8(7); 822–35. ©2018 AACR. See related commentary by Etxeberria et al., p. 794. This article is highlighted in the In This Issue feature, p. 781

Abstract: Purpose: The clinical utility of next-generation sequencing (NGS) in breast cancer has not been demonstrated. We hypothesized that we could perform NGS of a new biopsy from patients with metastatic triple-negative breast cancer (TNBC) in a clinically actionable timeframe. Experimental Design: We planned to enroll 40 patients onto a prospective study, Individualized Molecular Analyses Guide Efforts (IMAGE), to evaluate the feasibility of obtaining a new biopsy of a metastatic site, perform NGS (FoundationOne), and convene a molecular tumor board to formulate treatment recommendations within 28 days. We collected blood at baseline and at time of restaging to assess cell-free circulating plasma tumor DNA (ptDNA). Results: We enrolled 26 women with metastatic TNBC who had received ≥1 line of prior chemotherapy, and 20 (77%) underwent NGS of a metastatic site biopsy. Twelve (60%) evaluable patients received treatment recommendations within 28 days of consent. The study closed after 20 patients underwent NGS, based on protocol-specified interim futility analysis. Three patients went on to receive genomically directed therapies. Twenty-four of 26 patients had genetic alterations successfully detected in ptDNA. Among 5 patients, 4 mutations found in tumor tissues were not identified in blood, and 4 mutations found in blood were not found in corresponding tumors. In 9 patients, NGS of follow-up blood samples showed 100% concordance with baseline blood samples. Conclusions: This study demonstrates challenges of performing NGS on prospective tissue biopsies in patients with metastatic TNBC within 28 days, while also highlighting the potential use of blood as a more time-efficient and less invasive method of mutational assessment. Clin Cancer Res; 23(2); 379–86. ©2016 AACR.

Abstract: Rapid advancements in cancer genomics and in the development of targeted therapies provide expanding opportunities to use genomic profiling to improve patient outcomes. However, most patients do not have access to clinical genomic profiling platforms, and currently available assays capture a small set of known mutations or translocations tailored to specific tumor types. The spectrum of somatic alterations in leukemia, lymphoma, and myeloma includes substitutions, insertions/deletions (indels), copy number alterations (CNAs) and gene fusions; no current assay captures the different types of alterations in a single clinical genomic test. We developed a novel, CLIA-certified next-generation sequencing-based assay designed to provide targeted assessment of the genomic landscape of hematologic malignancies, including identification of all classes of genomic alterations using archived FFPE, blood and bone marrow aspirate samples with high accuracy in a clinically relevant timeframe. Methods DNA and RNA were successfully extracted from 350/362 (96%) specimens from 319 patients, including 57 FFPE samples, 150 blood samples and 142 bone marrow aspirates. The initial sample cohort included 20 ALL, 83 AML, 53 CLL, 57 DLBCL, 48 MDS, 32 MPN and 57 multiple myeloma samples. Adaptor ligated sequencing libraries were captured by solution hybridization using a custom bait-set targeting 374 cancer-related genes and 24 frequently rearranged genes by DNA-seq, and 258 frequently-rearranged genes by RNA-seq. All captured libraries were sequenced to high depth (Illumina HiSeq) in a CLIA-certified laboratory (Foundation Medicine), averaging 590x for DNA and 〉 20M total pairs for RNA, to enable the sensitive and specific detection of substitutions, indels, CNAs and gene fusions. Results Sufficient tumor content (≥20%) was present in 317/350 (91%) of the samples (289/319 patients), and a total of 885 alterations were identified (3.1 alterations per sample), including 555 base substitutions, 213 indels, 36 splice mutations, 51 CNAs and 36 fusions/rearrangements. The most frequent alterations across all hematologic malignancies included mutations in TP53 (9%), ASXL1, KRAS, NRAS, IDH2, TET2, SF3B1, JAK2, MLL2, DNMT3A, RUNX1, and SRSF2 (2-5% each); FLT3 ITDs (2%); MLL PTDs (1%); homozygous loss of CDKN2A/B (3%); and focal amplification of REL (1%). Rearrangements in BCL2/6, MYC, MLL, MLL2, NOTCH2, ABL1 and ETV6 were identified using DNA and RNA targeted sequencing, demonstrating the ability of this platform to reliably identify gene fusions with immediate clinical relevance. Overall high accuracy of the assay for substitutions, indels and CNAs was previously demonstrated by extensive validation studies achieving 95-99% across alteration types with high specificity (PPV 〉 99%) [Frampton et al, Nat Biotech, in press]. Comparison of detected alterations to previous molecular testing for JAK2, NPM1, IDH2, FLT3 and CEBPA in MPN/AML samples demonstrated 97% sensitivity (33/34) in our ability to identify known mutations in these clinical samples. We identified additional clinically relevant mutations that were not detected using standard clinical assays, including alterations in JAK2, FLT3 and IDH2, which can inform therapeutic decisions. The use of our content rich sequencing platform allowed us to identify clinically actionable mutations in hematologic malignancies, including IDH1/2 mutations in a spectrum of myeloid/lymphoid malignancies, recurrent BRAF mutations in refractory CLL and myeloma, and mutations in the JAK-STAT signaling pathway in diffuse-large B cell lymphoma. These results demonstrate that a targeted sequencing platform which includes a large set of known disease alleles/therapeutic targets can identify mutations with therapeutic relevance in disease contexts where gene-specific assays are not currently performed in the clinical setting. Conclusions We have developed a sensitive, high throughput assay to detect somatic alterations in hundreds of genes known to be deregulated in hematologic malignancies, which can be used for clinical sequencing of frozen/paraffin samples. We demonstrate that targeted DNA and RNA sequencing can be used to identify all classes of genomic alterations in genes known to be therapeutic targets in a broad spectrum of hematologic malignancies. Disclosures: Lipson: Foundation Medicine, Inc: Employment, Equity Ownership. Nahas:Foundation Medicine, Inc: Employment, Equity Ownership. Otto:Foundation Medicine, Inc: Employment, Equity Ownership. Yelensky:Foundation Medicine, Inc: Employment, Equity Ownership. Wang:Foundation Medicine, Inc: Employment, Equity Ownership. He:Foundation Medicine, Inc: Employment, Equity Ownership. Rampal:Foundation Medicine: Consultancy. Brennan:Foundation Medicine, Inc: Employment, Equity Ownership. Brennan:Foundation Medicine, Inc: Employment, Equity Ownership. Young:Foundation Medicine, Inc: Employment, Equity Ownership. Donahue:Foundation Medicine, Inc: Employment, Equity Ownership. Sanford:Foundation Medicine, Inc: Employment, Equity Ownership. Greenbowe:Foundation Medicine, Inc: Employment, Equity Ownership. Frampton:Foundation Medicine, Inc: Employment, Equity Ownership. Fichtenholtz:Foundation Medicine, Inc: Employment, Equity Ownership. Young:Foundation Medicine, Inc: Employment, Equity Ownership. Erlich:Foundation Medicine, Inc: Employment, Equity Ownership. Parker:Foundation Medicine, Inc: Employment, Equity Ownership. Ross:Foundation Medicine, Inc: Employment, Equity Ownership. Stephens:Foundation Medicine, Inc: Employment, Equity Ownership. Miller:Foundation Medicine, Inc: Employment, Equity Ownership. Levine:Foundation Medicine, Inc: Consultancy.

Abstract: Purpose: Micropapillary urothelial carcinoma (MPUC) is a rare and aggressive form of bladder cancer. We conducted genomic analyses [next-generation sequencing (NGS)] of MPUC and non-micropapillary urothelial bladder carcinomas (non-MPUC) to characterize the genomic landscape and identify targeted treatment options. Experimental Design: DNA was extracted from 40 μm of formalin-fixed paraffin-embedded sections from 15 MPUC and 64 non-MPUC tumors. Sequencing (NGS) was performed on hybridization-captured, adaptor ligation–based libraries to high coverage for 3,230 exons of 182 cancer-related genes plus 37 introns from 14 genes frequently rearranged in cancer. The results were evaluated for all classes of genomic alteration. Results: Mutations in the extracellular domain of ERBB2 were identified in 6 of 15 (40%) of MPUC: S310F (four cases), S310Y (one case), and R157W (one case). All six cases of MPUC with ERBB2 mutation were negative for ERBB2 amplification and Erbb2 overexpression. In contrast, 6 of 64 (9.4%) non-MPUC harbored an ERBB2 alteration, including base substitution (three cases), amplification (two cases), and gene fusion (one case), which is higher than the 2 of 159 (1.3%) protein-changing ERBB2 mutations reported for urinary tract cancer in COSMIC. The enrichment of ERBB2 alterations in MPUC compared with non-MPUC is significant both between this series (P & lt; 0.0084) and for all types of urinary tract cancer in COSMIC (P & lt; 0.001). Conclusions: NGS of MPUC revealed a high incidence of mutation in the extracellular domain of ERBB2, a gene for which there are five approved targeted therapies. NGS can identify genomic alteration, which inform treatment options for the majority of MPUC patients. Clin Cancer Res; 20(1); 68–75. ©2013 AACR.

Abstract: Gastric cancer (GC) is a major global cancer burden and the second most common cause of global cancer-related deaths. The addition of anti-ERBB2 (HER2) targeted therapy to chemotherapy improves survival for ERBB2-amplified advanced GC patients; however, the majority of GC patients do not harbor this alteration and thus cannot benefit from targeted therapy under current practice paradigms. Materials and Methods. Prospective comprehensive genomic profiling of 116 predominantly locally advanced or metastatic (90.0%) gastric cancer cases was performed to identify genomic alterations (GAs) associated with a potential response to targeted therapies approved by the U.S. Food and Drug Administration or targeted therapy-based clinical trials. Results. Overall, 78% of GC cases harbored one clinically relevant GA or more, with the most frequent alterations being found in TP53 (50%), ARID1A (24%), KRAS (16%), CDH1 (15%), CDKN2A (14%), CCND1 (9.5%), ERBB2 (8.5%), PIK3CA (8.6%), MLL2 (6.9%), FGFR2 (6.0%), and MET (6.0%). Receptor tyrosine kinase genomic alterations were detected in 20.6% of cases, primarily ERBB2, FGFR2, and MET amplification, with ERBB2 alterations evenly split between amplifications and base substitutions. Rare BRAF mutations (2.6%) were also observed. One MET-amplified GC patient responded for 5 months to crizotinib, a multitargeted ALK/ROS1/MET inhibitor. Conclusion. Comprehensive genomic profiling of GC identifies clinically relevant GAs that suggest benefit from targeted therapy including MET-amplified GC and ERBB2 base substitutions.

Abstract: Background: Micropapillary urothelial carcinoma of the urinary bladder (MPUC) encompasses approximately 5% of all bladder cancers and comprises approximately 3,000 to 4,000 new cases diagnosed each year in the US. MPUUPC is a highly aggressive form of bladder cancer associated with distant metastases and shortened patient survival. Once MPUC recurs progresses from loco-regional and progresses to metastatic disease, there is no currently no recognized effective treatment. We conducted a genomic analysis of a series of patients with MPUC to characterize the genomic landscape of MUPUC and identify targeted treatment options for patients with this lethal form of urologic malignancy. Methods: DNA was extracted from 40 microns of formalin-fixed paraffin embedded (FFPE) sections from 15 MPUC and 64 non-MPUC. Sequencing to high, uniform coverage was performed on hybridization-captured, adaptor ligated, hybridization capturedion based libraries for for 3,230 exons of 182 cancer-related genes plus 37 introns offrom 14 genes frequently rearranged in cancer to high, uniform coverage and evaluated for all classes of genomic alteration. Results: Extracellular domain mutations of ERBB2 were identified in 6/15 (40%) MPUC including: S310F (4 cases), S310Y (1 case) and R157W (1 case). All 6 cases of MPUC with ERBB2 mutation were negative for ERBB2 amplification which was confirmed by immunohistochemistry (IHC) in the 3 cases where additional tissue was available. In contrast, 6/64 (9.4%) of non-MPUC harbored an ERBB2 alteration: base substitutions (3 cases), amplifications (2 cases) and gene fusion (1 case), which is higher than the 2/159 (1.3%) of protein changing ERBB2 mutations reported in urinary tract cancer in COSMIC. The enrichment of ERBB2 alterations in MPUC compared to non-MPUC is significant inbetween this series (p & lt; 0.0084) and for all types of urinary tract cancer in COSMIC (p & lt; 0.001). All 9 ERBB2 WT MPUC cases harbored at least 1 actionable alteration, including alterations in AKT1, AKT2, CCND1, EGFR, PIK3CA, PIK3R1 and RAF1. Conclusions: Comprehensive genomic profiling of MPUC revealed actionable genomic alterations in all 15 specimens including a high incidence of ERBB2 extracellular domain mutation. We conclude that genomic profiling of MUPUC samples can reveal actionable alterations that can inform potential targeted treatment decisions for the majority of patients. Citation Information: Mol Cancer Ther 2013;12(11 Suppl):B122. Citation Format: Kai Wang, Jeff S. Ross, Laurie M. Gay, Rami N. Al-Rohil, Tipu Nazeer, Christine E. Sheehan, Timothy A. Jennings, Geoff A. Otto, Amy Donahue, Jie He, Gary Palmer, Siraj Ali, Michelle Nahas, Geneva Young, Elaine LaBrecque, Garrett Frampton, Rachel Erlich, John A. Curran, Tina Brennan, Sean R. Downing, Roman Yelensky, Doron Lipson, Matthew J. Hawryluk, Vincent A. Miller, Philip J. Stephens. A high frequency of activating extracellular domain ERBB2 (HER2) mutation in micropapillary urothelial carcinoma. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr B122.

Abstract: Histiocytic neoplasms are clonal, hematopoietic disorders characterized by an accumulation of abnormal, monocyte-derived dendritic cells or macrophages in Langerhans cell histiocytosis (LCH) and non-Langerhans cell histiocytosis (non-LCH), respectively. The discovery of BRAFV600E mutations in approximately 50% of these patients provided the first molecular therapeutic target in histiocytosis. However, recurrent driving mutations in the majority of patients with BRAFV600E–wild-type non-LCH are unknown, and recurrent cooperating mutations in non-MAP kinase pathways are undefined for the histiocytic neoplasms. Through combined whole-exome and transcriptome sequencing, we identified recurrent kinase fusions involving BRAF, ALK, and NTRK1, as well as recurrent, activating MAP2K1 and ARAF mutations in patients with BRAFV600E–wild-type non-LCH. In addition to MAP kinase pathway lesions, recurrently altered genes involving diverse cellular pathways were identified. Treatment of patients with MAP2K1- and ARAF-mutated non-LCH using MEK and RAF inhibitors, respectively, resulted in clinical efficacy, demonstrating the importance of detecting and targeting diverse kinase alterations in these disorders. Significance: We provide the first description of kinase fusions in systemic histiocytic neoplasms and activating ARAF and MAP2K1 mutations in non-Langerhans histiocytic neoplasms. Refractory patients with MAP2K1- and ARAF-mutant histiocytoses had clinical responses to MEK inhibition and sorafenib, respectively, highlighting the importance of comprehensive genomic analysis of these disorders. Cancer Discov; 6(2); 154–65. ©2015 AACR. This article is highlighted in the In This Issue feature, p. 109