Predictors and Prevalence of Nodal Disease in Salvage Oropharyngectomy.

BACKGROUND: Patients with recurrent oropharyngeal cancer often require extensive salvage surgery. For patients with clinically N0 necks, the indication for concurrent neck dissection remains unclear. This study aimed to determine predictors, prevalence, and distribution of nodal disease in patients treated with salvage oropharyngectomy. METHODS: In a case series with data collection at a single tertiary academic National Cancer Institute (NCI)-designated comprehensive cancer center, this study analyzed patients treated with prior radiation or chemoradiation who had persistent, recurrent, or second primary squamous cell carcinoma of the oropharynx requiring oropharyngeal resection between 1998 and 2017 (n = 95). Clinical and oncologic characteristics and treatment outcomes were collected, and statistical analyses were performed. RESULTS: The overall rate of nodal positivity was 21% (24/95), and the rate of occult nodal disease was 6% (4/65). Ipsilateral and contralateral level 2 were the most common areas harboring positive nodes. Bivariate analysis showed female sex (p = 0.01), initial overall stage (p = 0.02), and N status (p = 0.03), as well as recurrent overall and T stage (p = 0.05) to be predictors of nodal disease. In the multivariate analysis, recurrent T stage continued to be significantly predictive of pathologic nodal disease. Both computed tomography (CT) and positron emission tomography-CT were moderately accurate in predicting nodal disease in the salvage setting (area under the curve, 0.79 and 0.80, respectively). CONCLUSION: Occult nodal disease is observed in few patients undergoing salvage oropharyngeal resection. This study identified factors predictive of nodal disease in patients undergoing salvage oropharyngectomy and appropriate diagnostic tests in this setting.

Rationale for the advancement of PI3K pathway inhibitors for personalized chordoma therapy.

PURPOSE: Chordomas are rare and serious tumors with few effective treatments outside of aggressive surgery and radiation. Targeted therapies may present a more effective option for a subset of patients with lesions possessing certain genetic biomarkers. METHODS: A small molecule inhibitor library was tested in patient-derived UM-Chor1 cells to identify targeted therapies with potential efficacy. Targeted exome sequencing of UM-Chor1 and UM-Chor2 cells was performed to investigate genetic aberrations in relevant pathways. Chordoma cell lines were treated with inhibitors of the phosphotidylinositol 3-kinase (PI3K), epidermal growth factor receptor (EGFR), and cyclin dependent kinase (CDK) pathways, and responses were determined using resazurin cell viability assays, Annexin V apoptosis assays, and western blotting. Pan-PI3K inhibitor BKM120 was also tested in five chordoma xenograft models. RESULTS: Unbiased small molecule profiling nominated PI3K-AKT-mTOR pathway inhibitors as a promising therapy in chordoma, and genetic analyses of UM-Chor1 and UM-Chor2 cell lines revealed aberrations in PTEN, EGFR, and CDKN2A. Treatment of UM-Chor1 and UM-Chor2 with targeted PI3K, EGFR, and CDK inhibitors inhibited growth and proliferation and induced apoptosis more robustly than imatinib, a currently used chordoma therapy. Furthermore, BKM120 significantly inhibited tumor growth in a subset of the xenograft models tested. CONCLUSION: Targeted therapies, especially those inhibiting PI3K, display promising effects in multiple chordoma cell line and xenograft models. Nevertheless, the limited effects of PI3K, EGFR, and CDK targeting agents in other models reveal the presence of resistance mechanisms, which motivates future research to both identify biomarkers of response and develop combination therapies.

HPV-driven oncogenesis-much more than the E6 and E7 oncoproteins.

High-risk human papillomaviruses are well-established drivers of several cancer types including cervical, head and neck, penile as well as anal cancers. While the E6 and E7 viral oncoproteins have proven to be critical for malignant transformation, evidence is also beginning to emerge suggesting that both host pathways and additional viral genes may also be pivotal for malignant transformation. Here, we focus on the role of host APOBEC genes, which have an important role in molecular editing including in the response to the viral DNA and their role in HPV-driven carcinogenesis. Further, we also discuss data developed suggesting the existence of HPV-derived miRNAs in HPV + tumors and their potential role in regulating the host transcriptome. Collectively, while recent advances in these two areas have added complexity to the working model of papillomavirus-induced oncogenesis, these discoveries have also shed a light onto new areas of research that will be required to fully understand the process.

Integrative sequencing discovers an ATF1-motif enriched molecular signature that differentiates hyalinizing clear cell carcinoma from mucoepidemoid carcinoma.

OBJECTIVES: Salivary gland tumors are comprised of a diverse group of malignancies with widely varying prognoses. These cancers can be difficult to differentiate, especially in cases with limited potential for immunohistochemistry (IHC)-based characterization. Here, we sought to define the molecular profile of a rare salivary gland cancer called hyalinizing clear cell carcinoma (HCCC), and identify a molecular gene signature capable of distinguishing between HCCC and the histopathologically similar disease, mucoepidermoid carcinoma (MEC). MATERIALS AND METHODS: We performed the first integrated full characterization of five independent HCCC cases. RESULTS: We discovered insulin-like growth factor alterations and aberrant IGF2 and/or IGF1R expression in HCCC tumors, suggesting a potential dependence on this pathway. Further, we identified a 354 gene signature that differentiated HCCC from MEC, and was significantly enriched for genes with an ATF1 binding motif in their promoters, supporting a transcriptional pathogenic mechanism of the characteristic EWSR1-ATF1 fusion found in these tumors. Of the differentially expressed genes, IGF1R, SGK1 and SGK3 were found to be elevated in the HCCCs relative to MECs. Finally, analysis of immune checkpoints and subsequent IHC demonstrated that CXCR4 protein was elevated in several of the HCCC cases. CONCLUSION: Collectively, our data identify an ATF1-motif enriched gene signature that may have clinical utility for molecular differentiation of HCCCs from other salivary gland tumors and discover potential actionable alterations that may benefit the clinical care of recurrent HCCC patients.

Head and Neck Cancer Immunotherapy beyond the Checkpoint Blockade.

The success of immune checkpoint receptor blockade has brought exciting promises for the treatment of head and neck squamous cell carcinoma (HNSCC). While patients who respond to checkpoint inhibitors tend to develop a durable response, <15% of patients with HNSCC respond to immune checkpoint inhibitors, underscoring the critical need to alleviate cancer resistance to immunotherapy. Major advances have been made to elucidate the intrinsic and adaptive resistance mechanisms to immunotherapy. Central genomic events in HNSCC have been found to possess previously unknown roles in suppressing immune sensing. Such inhibitory function affects both the innate and adaptive arms of tumor-specific immunity. While checkpoint blockade effectively reinvigorates adaptive T-cell responses, additional targeting of the oncogenic inhibitors of innate immune sensing likely informs a novel and potent strategy for immune priming. This review discusses the recent advances on the identification of key HNSCC oncogenes that impair antitumor immunity and emerging immune-priming approaches that sensitize poorly immunogenic HNSCCs to checkpoint blockade. These approaches include but are not limited to cancer vaccine systems utilizing novel type I interferon agonists as immune adjuvants, radiation, DNA damage-inducing agents, and metabolic reprogramming. The goal of these multipronged approaches is to expand tumor-specific effector T-cells, break checkpoint receptor-mediated tolerance, and metabolically support sustained T-cell activation. The translation of therapeutics that reverses oncogenic inhibition of immune sensing requires thorough characterization of the HNSCC regulators of innate immune sensors, development of additional immunocompetent HNSCC mouse models, as well as engineering of more robust immune adjuvant delivery systems. Built on the success of checkpoint blockade, validation of novel immune-priming approaches holds key promises to expand the pool of responders to immunotherapy.

Novel Immunotherapeutic Approaches in Head and Neck Cancer.

Unresectable recurrent or metastatic head and neck cancer is an incurable disease with survival of approximately 12 months. Head and neck tumors exhibit numerous derangements in the tumor microenvironment that aid in immune evasion and may serve as targets for future therapies. Pembrolizumab is now approved as a first line therapy. Despite the promise of currently approved immunotherapies there continues to be low response rates and additional strategies are needed. Here, alterations in the immune microenvironment and current therapeutic strategies are reviewed with a focus on novel immunologic approaches.

Genomic sequencing and precision medicine in head and neck cancers.

Head and neck squamous cell carcinoma (HNSCC) remains a common and deadly disease. Historically, surgical and chemoradiation treatments have been met with modest success, and understanding of genetic drivers of HNSCC has been limited. With recent next generation sequencing studies focused on HNSCC, we are beginning to understand the genetic landscape of HNSCCs and are starting to identify and advance targeted options for patients. In this review, we describe current knowledge and recent advances in sequencing studies of HNSCC, discuss current limitations and future directions for further genomic analysis, and highlight the translational advances being undertaken to treat this important disease.

Surveilling the Potential for Precision Medicine-driven PD-1/PD-L1-targeted Therapy in HNSCC.

Immunotherapy is becoming an accepted treatment modality for many patients with cancer and is now approved for use in platinum-refractory recurrent or metastatic head and neck squamous cell carcinoma (HNSCC). Despite these successes, a minority of patients with HNSCC receiving immunotherapy respond to treatment, and few undergo a complete response. Thus, there is a critical need to identify mechanisms regulating immune checkpoints in HNSCC such that one can predict who will benefit, and so novel combination strategies can be developed for non-responders. Here, we review the immunotherapy and molecular genetics literature to describe what is known about immune checkpoints in common genetic subsets of HNSCC. We highlight several highly recurrent genetic lesions that may serve as biomarkers or targets for combination immunotherapy in HNSCC.

Moving towards personalised therapy in head and neck squamous cell carcinoma through analysis of next generation sequencing data.

Personalised medicine tumour boards, which leverage genomic data to improve clinical management, are becoming standard for the treatment of many cancers. This paper is designed as a primer to assist clinicians treating head and neck squamous cell carcinoma (HNSCC) patients with an understanding of the discovery and functional impact of recurrent genetic lesions that are likely to influence the management of this disease in the near future. This manuscript integrates genetic data from publicly available array comparative genome hybridization (aCGH) and next-generation sequencing genetics databases to identify the most common molecular alterations in HNSCC. The importance of these genetic discoveries is reviewed and how they may be incorporated into clinical care decisions is discussed. Considerations for the role of genetic stratification in the clinical management of head and neck cancer are maturing rapidly and can be improved by integrating data sets. This article is meant to summarise the discoveries made using multiple genomic platforms so that the head and neck cancer care provider can apply these discoveries to improve clinical care.