Tumor molecular profiling is a fundamental component of precision oncology, enabling the identification of genomic alterations in genes and pathways that can be targeted therapeutically. The existence of recurrent targetable alterations across distinct histologically-defined tumor types, coupled with an expanding portfolio of molecularly-targeted therapies, demands flexible and comprehensive approaches to profile clinically significant genes across the full spectrum of cancers. We established a large-scale, prospective clinical sequencing initiative utilizing a comprehensive assay, MSK-IMPACT, through which we have compiled matched tumor and normal sequence data from a unique cohort of more than 10,000 patients with advanced cancer and available pathological and clinical annotations. Using these data, we identified clinically relevant somatic mutations, novel non-coding alterations, and mutational signatures that were shared among common and rare tumor types. Patients were enrolled on genomically matched clinical trials at a rate of 11%. To enable discovery of novel biomarkers and deeper investigation into rare alterations and tumor types, all results are publicly accessible.

The identification of specific genetic alterations as key oncogenic drivers and the development of targeted therapies are together transforming clinical oncology and creating a pressing need for increased breadth and throughput of clinical genotyping. Next-generation sequencing assays allow the efficient and unbiased detection of clinically actionable mutations. To enable precision oncology in patients with solid tumors, we developed Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT), a hybridization capture-based next-generation sequencing assay for targeted deep sequencing of all exons and selected introns of 341 key cancer genes in formalin-fixed, paraffin-embedded tumors. Barcoded libraries from patient-matched tumor and normal samples were captured, sequenced, and subjected to a custom analysis pipeline to identify somatic mutations. Sensitivity, specificity, reproducibility of MSK-IMPACT were assessed through extensive analytical validation. We tested 284 tumor samples with previously known point mutations and insertions/deletions in 47 exons of 19 cancer genes. All known variants were accurately detected, and there was high reproducibility of inter- and intrarun replicates. The detection limit for low-frequency variants was approximately 2% for hotspot mutations and 5% for nonhotspot mutations. Copy number alterations and structural rearrangements were also reliably detected. MSK-IMPACT profiles oncogenic DNA alterations in clinical solid tumor samples with high accuracy and sensitivity. Paired analysis of tumors and patient-matched normal samples enables unambiguous detection of somatic mutations to guide treatment decisions.

IMPORTANCE Recurrent and/or metastatic head and neck cancer is usually incurable. Implementation of precision oncology for these patients has been limited by incomplete understanding of the molecular alterations underlying advanced disease. At the same time, the molecular profiles of many rare head and neck cancer types are unknown. These significant gaps in knowledge need to be addressed to rationally devise new therapies. OBJECTIVE To illuminate the distinct biology of recurrent and metastatic head and neck cancers and review implementation of precision oncology for patients with advanced disease. DESIGN, SETTING, AND PARTICIPANTS After exclusions, 151 patients with advanced, treatment-resistant head and neck tumors, including squamous cell carcinoma (HNSCC), adenoid cystic carcinoma (ACC), and other salivary and cutaneous cancers, whose tumors were sequenced between January 2014 and July 2015 at Memorial Sloan Kettering were recruited. Next-generation sequencing of tumors as part of clinical care included high-depth (median 600×) exonic coverage of 410 cancer genes and whole-genome copy number analysis. INTERVENTIONS Next-generation sequencing of tumors and matched normal DNA. MAIN OUTCOMES AND MEASURES Feasibility, the frequency of actionable molecular alterations, the effect on decision making, and identification of alterations associated with recurrent and metastatic disease. RESULTS Overall, 151 patients (95 men and 56 women; mean [range] age, 61.8 [17-100] years) were included in the study. Next-generation sequencing ultimately guided therapy in 21 of 151 patients (14%) (13 of 53 [25%] of patients with HNSCC) by refining diagnoses and matching patients to specific therapies, in some cases with dramatic responses on basket studies. Molecular alterations were potentially actionable in 28 of 135 patients (21%). The genetic profiles of recurrent and metastatic tumors were often distinct from primary tumors. Compared to primary human papillomavirus (HPV)-positive tumors, many recurrent and metastatic HPV-positive tumors exhibited a molecular profile more similar to HPV-negative tumors, including enriched frequencies of TP53 mutation (3 of 20 tumors [15%]), whole genome duplication (5 of 20 tumors [25%]), and 3p deletion (11 of 20 tumors [55%]). There were high rates of TERT promoter mutation in recurrent and metastatic HPV-negative HNSCC (13 of 30 tumors [43%]), cutaneous SCC (11 of 21 tumors [52%]), basal cell carcinoma (3 of 4 tumors [75%]), and ACC (5 of 36 tumors [14%]). Activating NOTCH1 mutations were enriched in metastatic ACCs (8 of 36 tumors [22%]). CONCLUSIONS AND RELEVANCE These findings reveal the molecular landscape of advanced disease and rare cancer subtypes, both predominant challenges in head and neck oncology. To understand the repertoire of targetable alterations in advanced cancers, it is necessary to sequence recurrent and metastatic tumors. These data are important first steps toward implementation of precision head and neck oncology.