The hidden link of exosomes to head and neck cancer

Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Head and neck squamous cell carcinoma (HNSCC) represents an aggressive and heteroge-nous group of cancers whose pathologies remain largely unresolved. Despite recent advances in HNSCC therapeutic strategies, the overall survival of HNSCC patients remains poor and continues to prompt efforts to develop more effective therapies. Exosomes are a subtype of extracellular vesicles secreted by a variety of cells that have begun to spark significant interest in their roles in cancer. As membranous vesicles, spanning from 30–150 nm in diameter, exosomes mediate the transport of various molecules, such as proteins, nucleic acids, and lipids, intercellularly throughout the body. In doing so, exosomes not only act to deliver materials to cancer cells but also as signals that can confer their progression. Accumulating evidence shows the direct correlation between exosomes and the aggressiveness of HNSCC. However, more research is warranted in this field to further our under-standing. In this review, we attempt to highlight the tumor-supporting roles and therapeutic potential of exosomes in HNSCC. We introduce first the biogenesis and component features of exosomes, followed by their involvement in HNSCC proliferation and metastasis. We then move on to discuss HNSCC-derived exosomes’ influence on the tumor microenvironment and their function in tumor drug resistance. Finally, we explore the promising potential of exosomes as HNSCC biomarkers and therapeutic targets and drug carriers for HNSCC treatments.Peer reviewe

Determinants of delay and association with outcome in head and neck cancer:A systematic review

Introduction: Head and neck cancers (HNC) are relatively fast-growing tumours, and delay in treatment initiation is associated with tumour progression and adverse outcome. An overview of factors contributing to delay can provide critical insights on necessary adjustments to optimize care pathways. This systematic review aims to identify factors associated with delay and summarize the effect of delay on oncological outcome measures. Methods: A search strategy was conducted according to PRISMA guidelines to search electronic data-bases for studies assessing the carepathway interval (days between first visit in head and neck oncology center and treatment initiation) and/or time-to-treatment-initiation interval (days between histological diagnosis and treatment initiation) and 1) determinants of delay and/or 2) effect of delay on outcome within these timeframes. Due to heterogeneity between included studies, a meta-analysis was not possible. Results: Fifty-two studies were eligible for quantitative analysis. Non-Caucasian race, academic setting, Medicaid/no insurance and radiotherapy as primary treatment were associated with delay. Advanced tumour stage was related to increased time-to-treatment initiation in the four common sites combined (oral cavity, oropharynx, hypopharynx, larynx). Separate determinants for delay in different tumour locations were identified. In laryngeal, oral cavity cancer and the four common HNC sites combined, delay in start of treatment is associated with decreased overall survival, although no cut-off time point could be determined. Conclusion: Race, facility type, type of insurance and radiotherapy as primary treatment were associated with delay and subsequent inferior survival in the four common sites combined. (C) 2021 The Authors. Published by Elsevier Ltd

A systematic review and recommendations on the use of plasma EBV DNA for nasopharyngeal carcinoma

Introduction: Nasopharyngeal carcinoma (NPC) is an endemic malignancy in Southeast Asia, particularly Southern China. The classical non-keratinising cell type is almost unanimously associated with latent Epstein-Barr virus (EBV) infection. Circulating plasma EBV DNA can be a useful biomarker in various clinical aspects, but comprehensive recommendations and international guidelines are still lacking. We conducted a systematic review of all original articles on the clinical application of plasma EBV DNA for NPC; we further evaluated its strengths and limitations for consideration as standard recommendations. Methods: The search terms 'nasopharyngeal OR nasopharynx', and 'plasma EBV DNA OR cell-free EBV OR cfEBV' were used to identify full-length articles published up to December 2020 in the English literature. Three authors independently reviewed the article titles, removed duplicates and reviewed the remaining articles for eligibility. Results: A total of 81 articles met the eligibility criteria. Based on the levels of evidence and grades of recommendation assessed, it is worth considering the inclusion of plasma EBV DNA in screening, pre-treatment work-up for enhancing prognostication and tailoring of treatment strategy, monitoring during radical treatment, post-treatment surveillance for early detection of relapse, and monitoring during salvage treatment for recurrent or metastatic NPC. One major limitation is the methodology of measurement requiring harmonisation for consistent comparability. Conclusions: The current comprehensive review supports the inclusion of plasma EBV DNA in international guidelines in the clinical aspects listed, but methodological issues must be resolved before global application. 2021 Elsevier Ltd. All rights reserved

The controversy in the management of the N0 neck for squamous cell carcinoma of the maxillary sinus

Squamous cell carcinoma (SCC) of the maxillary sinus is a relatively rare disease. As the reported incidence of regional metastasis varies widely, controversy exists as to whether or not the N0 classified neck should be treated electively. In this review, the data from published series are analyzed to decide on a recommendation of elective treatment of the neck in maxillary SCC. The published series consist of heterogeneous populations of different subsites of the paranasal sinuses, different histological types, different staging and treatment modalities used and different ways of reporting the results. These factors do not allow for recommendations based on high levels of evidence. Given this fact, the relatively high incidence rate of regional metastasis at presentation or in follow-up in the untreated N0 neck, and the relatively low toxicity of elective neck irradiation, such irradiation in SCC of the maxillary sinus should be considered

Current management of stage IV nasopharyngeal carcinoma without distant metastasis

Up to one in four patients with nasopharyngeal carcinoma present with non-metastatic stage IV disease (i.e. T4 or N3). Distinct failure patterns exist, despite the routine adoption of contemporary treatment modalities such as intensity modulated radiotherapy and systemic chemotherapy. Concurrent chemoradiotherapy (CCRT) followed by adjuvant chemotherapy or induction chemotherapy followed by CCRT are commonly employed in this setting, with the latter emerging as the preferred option. Additionally, emerging radiation technologies like proton therapy has become available offering new opportunities for prevention of radiation-induced side effects. This article reviews not only the current treatment strategies, but also discusses novel ways to tackle this challenging disease with respect to the patterns of failure

Incidence of Occult Lymph Node Metastasis in Primary Larynx Squamous Cell Carcinoma, by Subsite, T Classification and Neck Level: A Systematic Review

Background: Larynx cancer is a common site for tumors of the upper aerodigestive tract. In cases with a clinically negative neck, the indications for an elective neck treatment are still debated. The objective is to define the prevalence of occult metastasis based on the subsite of the primary tumor, T classification and neck node levels involved. Methods: All studies included provided the rate of occult metastases in cN0 larynx squamous cell carcinoma patients. The main outcome was the incidence of occult metastasis. The pooled incidence was calculated with random effects analysis. Results: 36 studies with 3803 patients fulfilled the criteria. The incidence of lymph node metastases for supraglottic and glottic tumors was 19.9% (95% CI 16.4–23.4) and 8.0% (95% CI 2.7–13.3), respectively. The incidence of occult metastasis for level I, level IV and level V was 2.4% (95% CI 0–6.1%), 2.0% (95% CI 0.9–3.1) and 0.4% (95% CI 0–1.0%), respectively. For all tumors, the incidence for sublevel IIB was 0.5% (95% CI 0–1.3). Conclusions: The incidence of occult lymph node metastasis is higher in supraglottic and T3–4 tumors. Level I and V and sublevel IIB should not be routinely included in the elective neck treatment of cN0 laryngeal cancer and, in addition, level IV should not be routinely included in cases of supraglottic tumors

Management of locally recurrent nasopharyngeal carcinoma

As a consequence of the current excellent loco-regional control rates attained using the generally accepted treatment paradigms involving intensity-modulated radiotherapy for nasopharyngeal carcinoma (NPC), only 10-20% of patients will suffer from local and/or nodal recurrence after primary treatment. Early detection of recurrence is important as localized recurrent disease is still potentially salvageable, but this treatment often incurs a high risk of major toxicities. Due to the possibility of radio-resistance of tumors which persist or recur despite adequate prior irradiation and the limited tolerance of adjacent normal tissues to sustain further additional treatment, the management of local failures remains one of the greatest challenges in this disease. Both surgical approaches for radical resection and specialized re-irradiation modalities have been explored. Unfortunately, available data are based on retrospective studies, and the majority of them are based on a small number of patients or relatively short follow-up. In this article, we will review the different salvage treatment options and associated prognostic factors for each of them. We will also propose a treatment algorithm based on the latest available evidence and discuss the future directions of treatment for locally recurrent NPC.Peer reviewe