Laryngeal preneoplastic lesions and cancer: challenging diagnosis. Qualitative literature review and meta-analysis

Discrimination of vocal folds lesions by multiclass classification using autofluorescence spectroscopy: An ex vivo study

BACKGROUND

Autofluorescence spectroscopy is effective for noninvasive detection but underutilized in tissue with various pathology analyses. This study evaluates whether AFS can be used to discriminate between different types of laryngeal lesions in view of assisting in vocal fold surgery and preoperative investigations.

METHODS

A total of 1308 spectra were recorded from 29 vocal fold samples obtained from 23 patients. Multiclass analysis was performed on the spectral data, categorizing lesions into normal, benign, dysplastic, or carcinoma.

RESULTS

Through an appropriate selection of spectral components and a cascading classification approach based on artificial neural networks, a classification rate of 97% was achieved for each lesion class, compared to 52% using autofluorescence intensity.

CONCLUSIONS

The ex vivo study demonstrates the effectiveness of AFS combined with multivariate analysis for accurate classification of vocal fold lesions. Comprehensive analysis of spectral data significantly improves classification accuracy, such as distinguishing malignant from precancerous or benign lesions.

Clinical significance of type IV vascularization of laryngeal lesions according to the Ni classification

Background

Scattered, small, dot-like intraepithelial papillary capillary loops (IPCLs) represent type IV epithelial vascularization according to "Ni classification" and are considered to be nonmalignant. According to the European Laryngological Society classification, these loops are malignant vascular changes. This contradiction has high clinical importance; therefore, clarification of the clinical significance of type IV vascularization according to the Ni classification is needed.

Methods

The study was performed between June 2015 and December 2022. All recruited patients (n = 434) were symptomatic, with macroscopic laryngeal lesions (n = 674). Patients were investigated using the enhanced endoscopic methods of narrow band imaging (NBI) and the Storz Professional Image Enhancement System (IMAGE1 S). The microvascular patterns in the lesions were categorized according to Ni classification from 2011 and all lesions were examined histologically.

Results

A total of 674 lesions (434 patients) were investigated using flexible NBI endoscopy and IMAGE1 S endoscopy. Type IV vascularization was recognized in 293/674 (43.5%) lesions. Among these 293 lesions, 178 (60.7%) were benign (chronic laryngitis, hyperplasia, hyperkeratosis, polyps, cysts, granulomas, Reinkeho oedema and recurrent respiratory papillomatosis); 9 (3.1%) were squamous cell carcinoma; 61 (20.8%) were mildly dysplastic, 29 (9.9%) were moderately dysplastic, 14 (4.8%) were severe dysplastic and 2 (0.7%) were carcinoma in situ. The ability to recognize histologically benign lesions in group of nonmalignant vascular pattern according to Ni (vascularization type I-IV) and distinguish them from precancers and malignancies was with accuracy 75.5%, sensitivity 54.4%, specificity 94.4%, positive predictive value 89.6% and negative predictive value 69.9%.

Conclusion

Laryngeal lesions with type IV vascularization as defined by Ni present various histological findings, including precancerous and malignant lesions. Patients with type IV vascularization must be followed carefully and, in case of progression mucosal lesion microlaryngoscopy and excision are indicated.

Comparison of narrow-band imaging with autofluorescence imaging for endoscopic detection of squamous cell carcinoma of the tonsil

PURPOSE

Early detection of mucosal neoplastic lesions is crucial for a patient's prognosis. This has led to the development of effective optical endoscopic diagnostic methods such as narrow band imaging (NBI) and autofluorescence (AFI). Independent of each other, both of these methods were proven useful in the detection of mucosal neoplasias. There are limited reported data comparing both methods for oropharyngeal cancer diagnostics. The aim of the study was to compare NBI and AFI endoscopic visualization of signs in identifying tonsillar squamous cell carcinoma (SCC) and assessing its extent and to determine whether the score was related to the evaluator's experience.

METHODS

Patients with tonsillar SCC underwent endoscopic pharyngeal examination using NBI and AFI. Fiftyseven video sequences of examinations of lesions proven to be SCC were evaluated by three reviewers. The accuracy of determination of lesion extent and visualization of its endoscopic signs of malignancy were evaluated.

RESULTS

Endoscopic visualization of tumour spread was significantly better using AFI than NBI (p = 0.0003). No significant difference was found between NBI and AFI in the visualization of endoscopic malignancy determining signs (p = 0.1405). No significant difference was found among the three reviewers in the visualization of tumour spread and for identifying malignancy-determining signs in NBI endoscopy or AFI endoscopy.

CONCLUSIONS

The results show that AFI obtained better results for assessing the extent of tonsillar cancers than NBI. Both methods were proven to be equal in the visualization of endoscopic malignancy-determining signs. Both are useful even for less experienced evaluators.

Predicting survival of advanced laryngeal squamous cell carcinoma: comparison of machine learning models and Cox regression models

Laryngeal squamous cell carcinoma (LSCC) is a common tumor type. High recurrence rates remain an important factor affecting the survival and quality of life of advanced LSCC patients. We aimed to build a new nomogram and a random survival forest model using machine learning to predict the risk of LSCC progress. The study included 671 patients with AJCC stages III-IV LSCC. To develop a prognostic model, Cox regression analyses were used to assess the relationship between clinic-pathologic factors and disease-free survival (DFS). RSF analysis was also used to predict the DFS of LSCC patients. The ROC curve revealed that the Cox model exhibited good sensitivity and specificity in predicting DFS in the training and validation cohorts (1 year, validation AUC = 0.679, training AUC = 0.693; 3 years, validation AUC = 0.716, training AUC = 0.655; 5 years, validation AUC = 0.717, training AUC = 0.659). Random survival forest analysis showed that N stage, clinical stage, and postoperative chemoradiotherapy were prognostically significant variables associated with survival. The random forest model exhibited better prediction ability than the Cox regression model in the training cohort; however, the two models showed similar prediction ability in the validation cohort.

Contact Endoscopy - Narrow Band Imaging (CE-NBI) data set for laryngeal lesion assessment

The endoscopic examination of subepithelial vascular patterns within the vocal fold is crucial for clinicians seeking to distinguish between benign lesions and laryngeal cancer. Among innovative techniques, Contact Endoscopy combined with Narrow Band Imaging (CE-NBI) offers real-time visualization of these vascular structures. Despite the advent of CE-NBI, concerns have arisen regarding the subjective interpretation of its images. As a result, several computer-based solutions have been developed to address this issue. This study introduces the CE-NBI data set, the first publicly accessible data set that features enhanced and magnified visualizations of subepithelial blood vessels within the vocal fold. This data set encompasses 11144 images from 210 adult patients with pathological vocal fold conditions, where CE-NBI images are annotated using three distinct label categories. The data set has proven invaluable for numerous clinical assessments geared toward diagnosing laryngeal cancer using Optical Biopsy. Furthermore, given its versatility for various image analysis tasks, we have devised and implemented diverse image classification scenarios using Machine Learning (ML) approaches to address critical clinical challenges in assessing laryngeal lesions.

Real-time detection of laryngopharyngeal cancer using an artificial intelligence-assisted system with multimodal data

BACKGROUND

Laryngopharyngeal cancer (LPC) includes laryngeal and hypopharyngeal cancer, whose early diagnosis can significantly improve the prognosis and quality of life of patients. Pathological biopsy of suspicious cancerous tissue under the guidance of laryngoscopy is the gold standard for diagnosing LPC. However, this subjective examination largely depends on the skills and experience of laryngologists, which increases the possibility of missed diagnoses and repeated unnecessary biopsies. We aimed to develop and validate a deep convolutional neural network-based Laryngopharyngeal Artificial Intelligence Diagnostic System (LPAIDS) for real-time automatically identifying LPC in both laryngoscopy white-light imaging (WLI) and narrow-band imaging (NBI) images to improve the diagnostic accuracy of LPC by reducing diagnostic variation among on-expert laryngologists.

METHODS

All 31,543 laryngoscopic images from 2382 patients were categorised into training, verification, and test sets to develop, validate, and internal test LPAIDS. Another 25,063 images from five other hospitals were used as external tests. Overall, 551 videos were used to evaluate the real-time performance of the system, and 200 randomly selected videos were used to compare the diagnostic performance of the LPAIDS with that of laryngologists. Two deep-learning models using either WLI (model W) or NBI (model N) images were constructed to compare with LPAIDS.

RESULTS

LPAIDS had a higher diagnostic performance than models W and N, with accuracies of 0·956 and 0·949 in the internal image and video tests, respectively. The robustness and stability of LPAIDS were validated in external sets with the area under the receiver operating characteristic curve values of 0·965-0·987. In the laryngologist-machine competition, LPAIDS achieved an accuracy of 0·940, which was comparable to expert laryngologists and outperformed other laryngologists with varying qualifications.

CONCLUSIONS

LPAIDS provided high accuracy and stability in detecting LPC in real-time, which showed great potential for using LPAIDS to improve the diagnostic accuracy of LPC by reducing diagnostic variation among on-expert laryngologists.

Difficult glottis: Diagnostic dilemma in viewof the clinical presentation

<br><b>Introduction:</b> The taxonomy of vocal fold lesions has been refined, and it serves as a common descriptive language for diagnosis, treatment algorithms, and reporting of outcomes. However, we observe rare cases when numerous pathologies overlap, resulting in an unclear and complicated clinical presentation of the glottis.</br> <br><b>Aim:</b> The aim of this paper is to present cases of overlapping etiopathological factors which poses a challenge when making a diagnosis and referring a patient for adequate treatment.</br> <br><b>Material and method:</b> The study presents different photographs of the glottis, including some unique and unusual images in which overlapping pathologies were captured. The photographs are accompanied by case descriptions, comments, and pathological analyses.</br> <br><b>Results:</b> Four selected photographs showed a bunch of exophytic growth lesions with foci of whitish plaques, covered by yellowish crusts, with thinned, reddened vocal folds presenting foci of leukoplakia. The study discussed possible causes of vocal folds edema, diffuse erythema, presence of crusts or exudate, whitish debris/plaques or development of leukoplakia, non-neoplastic ulceration, as well as injected and reddened mucous membrane. Chronic infectious laryngitis, idiopathic ulcerative laryngitis, and drug-induced laryngitis were also mentioned. The study also raised the issues concerning diabetics and patients treated with inhaled corticosteroids, including candidiasis and primary aspergillosis of the larynx.</br> <br><b>Conclusions:</b> To conclude, everyday clinical practice involves encountering cases of unclear onset and course, with complicated presentation of the glottis. Therefore, comprehensive history-taking and thorough investigation of systemic causes are of immense importance. Recommended management includes conducting the most meticulous differential diagnosis, implementing treatment for the most likely cause, and, whenever possible, refraining from biopsy in order to avoid permanent damage to vocal cords.</br>.

Narrow Band Imaging Technology: Role in the Detection of Recurrent Laryngeal and Hypopharyngeal Cancers Post-radiotherapy

To assess the diagnostic accuracy of NBI endoscopy for the diagnosis of early recurrent laryngeal and hypopharyngeal cancers after radiotherapy. The study was conducted over a period of two and a half years from June 2019 to February 2022 and included 123 post-RT patients with laryngeal and hypopharyngeal cancers. The patients were planned for endoscopy with white light and narrow-band imaging. The biopsy was carried out in NBI suspected lesions and sent for histopathological examination. The pathologist was blinded to the outcome of NBI and WLE results to eliminate observer bias. The age group most commonly affected in our study was 40-50 years. Out of the 123 patients, 106 were males and 17 were females. The overall Sensitivity, Specificity, Positive predictive value and Negative predictive value of NBI for malignant lesions were 90.6%, 99%, 95.2% and 98% respectively. NBI Technology is a first-rate diagnostic tool that can help in diagnosing early recurrent cancer lesions, especially after RT, in which the recurrence is otherwise difficult to differentiate from post-radiotherapy oedema. This technology can significantly reduce the rates of failure to detect cancers in early stages.

Diagnostic Assessment (Imaging) and Staging of Laryngeal Cancer

Diagnosis of larynx cancer relies on a detailed history and physical and objective assessment with endoscopy and imaging. Endoscopy is needed to assess for vocal fold function that directly affects staging. Computed tomography and MRI can be used to assess for tumor extent in relation to intra- and extra-laryngeal structures, especially paraglottic and pre-epiglottic space involvement as well as cartilage invasion. Accurate staging is critical for subsequent treatment decision-making regarding larynx preservation.

Ultrasound-guided core needle biopsy for accessing laryngeal masses with unsatisfactory laryngoscopy and biopsy results

BACKGROUND

Laryngoscopy and biopsy is the standard techniques to sample and diagnose laryngeal neoplasms, but not all patients with laryngeal neoplasm are eligible for biopsy via laryngoscopy (e.g., submucosal neoplasms).

PURPOSE

This study was conducted to evaluate the feasibility and diagnostic yield of ultrasound-guided core needle biopsy (US-CNB) for submucosal laryngeal neoplasms with unsatisfactory laryngoscopy and biopsy results.

METHODS

We retrospectively reviewed the medical records of 24 patients with unsatisfactory laryngoscopy and biopsy results who were referred to our center for US-CNB from January 2017 to November 2021. For all enrolled patients, we assessed consistency between the laryngoscopic biopsy, US-CNB, and final results. The final results were determined from the surgical biopsy results or clinical follow-up information (at least 3 month). Differences between biopsy techniques were compared using the Fisher's exact test. A P value less than 0.05 indicated statistical significance.

RESULTS

Twenty-four patients (median [range] age: 60.6 [41-76] years, 20 men) were included in our study. Among the 24 patients, 12 were eligible for laryngoscopic biopsy. In total, 24 patients underwent 26 US-CNB. Two patients underwent a repeat US-CNB for conformation of a benign histological result or due to inadequate specimen collection. The results of laryngoscopic biopsy and US-CNB were compared with the final result. The overall accuracy of US-CNB for differentiating benign from malignant lesions was 95.8 % (23/24), and this procedure had a sensitivity, specificity, positive predictive value, and negative predictive value of 95.2 %, 100 %, 100 %, and 75 %, respectively. The results of US-CNB are significantly better than those of laryngoscopic biopsy.

CONCLUSIONS

US-CNB is a safe, effective, and feasible technique for investigating suspicious submucosal laryngeal neoplasms and can serve as a complementary method for early and timely diagnosis of those neoplasms.

From Hype To Reality: A Narrative Review on the Promising Role of Artificial Intelligence in Larynx Cancer Detection and Transoral Microsurgery

Early larynx cancer detection plays a crucial role in improving treatment outcomes and recent studies have shown promising results in using artificial intelligence for larynx cancer detection. Artificial intelligence also has the potential to enhance transoral larynx microsurgery. This narrative review summarizes the current evidence regarding its use in larynx cancer detection and potential applications in transoral larynx microsurgery. The utilization of artificial intelligence in larynx cancer detection with white light endoscopy and narrow-band imaging helps improve diagnostic accuracy and efficiency. It can also potentially enhance transoral larynx microsurgery by aiding surgeons in real-time decision-making and minimizing the risk of complications. However, further prospective studies are warranted to validate the findings, and additional research is necessary to optimize the integration of artificial intelligence in our clinical practice.

Role of Narrow Band Imaging in Laryngeal Lesions: A Prospective Study from Southern India

To assess the utility of Narrow Band Imaging (NBI) as a diagnostic tool in evaluating laryngeal pathology in patients presenting with hoarseness. Study design: Prospective cross sectional diagnostic study. Methods: 200 patients with voice change were recruited and laryngeal findings documented with high definition flexible endoscopy with both white light and narrow band light and the representative still images recorded for analysis. The NBI intraepithelial papillary capillary loop (IPCL) patterns was compared with the histopathology report. Of the 200 patients evaluated, 84 lesions were biopsied which included both benign and malignant lesions. The sensitivity obtained was 73.3% [54.1-87.7% with 95% CI] and the specificity was 87% [75.1-94.6% with 95% CI] for detecting malignant lesions. NBI can be considered as a useful diagnostic tool in evaluating laryngeal pathology and can be used to detect early premalignant and malignant lesions.

Artificial Intelligence in Laryngeal Endoscopy: Systematic Review and Meta-Analysis

Background: Early diagnosis of laryngeal lesions is necessary to begin treatment of patients as soon as possible to preserve optimal organ functions. Imaging examinations are often aided by artificial intelligence (AI) to improve quality and facilitate appropriate diagnosis. The aim of this study is to investigate diagnostic utility of AI in laryngeal endoscopy. Methods: Five databases were searched for studies implementing artificial intelligence (AI) enhanced models assessing images of laryngeal lesions taken during laryngeal endoscopy. Outcomes were analyzed in terms of accuracy, sensitivity, and specificity. Results: All 11 studies included presented an overall low risk of bias. The overall accuracy of AI models was very high (from 0.806 to 0.997). The accuracy was significantly higher in studies using a larger database. The pooled sensitivity and specificity for identification of healthy laryngeal tissue were 0.91 and 0.97, respectively. The same values for differentiation between benign and malignant lesions were 0.91 and 0.94, respectively. The comparison of the effectiveness of AI models assessing narrow band imaging and white light endoscopy images revealed no statistically significant differences (p = 0.409 and 0.914). Conclusion: In assessing images of laryngeal lesions, AI demonstrates extraordinarily high accuracy, sensitivity, and specificity.

Deep Convolution Neural Network for Laryngeal Cancer Classification on Contact Endoscopy-Narrow Band Imaging

(1) Background: Contact Endoscopy (CE) and Narrow Band Imaging (NBI) are optical imaging modalities that can provide enhanced and magnified visualization of the superficial vascular networks in the laryngeal mucosa. The similarity of vascular structures between benign and malignant lesions causes a challenge in the visual assessment of CE-NBI images. The main objective of this study is to use Deep Convolutional Neural Networks (DCNN) for the automatic classification of CE-NBI images into benign and malignant groups with minimal human intervention. (2) Methods: A pretrained Res-Net50 model combined with the cut-off-layer technique was selected as the DCNN architecture. A dataset of 8181 CE-NBI images was used during the fine-tuning process in three experiments where several models were generated and validated. The accuracy, sensitivity, and specificity were calculated as the performance metrics in each validation and testing scenario. (3) Results: Out of a total of 72 trained and tested models in all experiments, Model 5 showed high performance. This model is considerably smaller than the full ResNet50 architecture and achieved the testing accuracy of 0.835 on the unseen data during the last experiment. (4) Conclusion: The proposed fine-tuned ResNet50 model showed a high performance to classify CE-NBI images into the benign and malignant groups and has the potential to be part of an assisted system for automatic laryngeal cancer detection.

Diagnostic value of autofluorescence laryngoscope in early laryngeal carcinoma and precancerous lesions: A systematic review and meta-analysis

OBJECTIVE

We aim to evaluate the diagnostic value of autofluorescence laryngoscope (AFL) in early laryngeal carcinoma and precancerous lesions. aWe also assess the value of AFL in diagnosis of early laryngeal carcinoma and precancerous lesions in comparison with that of white light laryngoscope (WL).

METHODS

The databases consisting of PubMed, Cochrane Library, Web of science and CNKI were systematically searched to find pertinent literatures of AFL in diagnosing early laryngeal carcinoma and precancerous lesions. We made a quality evaluation of every study we included using the modified Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). The pooled sensitivities, specificities were calculated using Meta-Disc 1.4. And we estimated the summary receiver operating characteristic curves (SROC) and area under the curves (AUC).

RESULTS

We finally included 23 studies. The results of AFL in diagnosing early laryngeal carcinoma and precancerous lesions showed higher sensitivity of 0.91 (95%CI: 0.89-0.93; χ²=43.78, p = 0.0025) and specificity of 0.80 (95%CI: 0.77-0.82; χ²=130.64, p = 0.000), and the weighted AUC of AFL was 0.948 ± 0.013 (95%CI: 0.921-0.974) and the diagnostic accuracy (Q*) was 0.887 ± 0.018. The sensitivity and specificity of WL were 0.74 (95%CI: 0.70-0.77; χ²=52.40, p = 0.000) and 0.89 (95%CI: 0.87-0.90; χ²=299.22, p = 0.000), and the weighted AUC of WL was 0.835 ± 0.029 (95%CI: 0.777-0.892) and the diagnostic accuracy (Q*) was 0.767 ± 0.027.

CONCLUSION

The meta-analysis and systematic review suggested that AFL had high diagnostic value in early laryngeal carcinoma and precancerous lesions, and its diagnostic value was higher than that of WL. These results indicated that AFL can provide good guidance for the early detection of laryngeal carcinoma and precancerous lesions.

Knockdown of Circular RNA hsa_circ_PVT1 Inhibited Laryngeal Cancer Progression via Preventing wnt4/β-Catenin Signaling Pathway Activation

Aim

To explore the function and mechanism of circular has_circ_PVT1 on laryngeal cancer (LC).

Methods

Microarray chip was performed to screen the differential expression of circRNA. Western blot and qRT-PCR was employed to detect the protein and mRNA level. CCK-8, clone formation, cell cycle, wound healing, and Transwell assay were performed to detect the cell proliferation, migration, and invasion ability. Luciferase assay and Fish were used to confirm the relationship between circ_PVT1/CBX4 and miR-21-5p. Flow cytometry and TUNEL assay were carried out to assess the apoptosis level.

Results

The upregulation of circ_PVT1 was found in LC tissues and cells. Silencing of circ_PVT1 inhibited LC progression via targeting miR-21-5p and indirectly controlling CBX4. Wnt4/β-catenin signal pathway was inactivated by inhibiting the expression of circ_PVT1.

Conclusion

Knockdown of circ_PVT1 prevented LC progression via targeting miR-21-5p/CBX4 by inhibiting wnt4/β-catenin signal pathway, which could provide a novel therapeutic target for LC.

Vocal Fold Leukoplakia: Which of the Classifications of White Light and Narrow Band Imaging Most Accurately Predicts Laryngeal Cancer Transformation? Proposition for a Diagnostic Algorithm

The management of Vocal Fold Leukoplakia (VFL) remains problematic. There is no consensus on the indications or the timing for surgery. The objective was to select the most accurate classification for predicting low- and high-risk VFL in White Light Imaging (WLI) and Narrow Band Imaging (NBI) and to establish a diagnostic algorithm with a timely referral for treatment. A total of 259 VFL patients were included in the study; 186 lesions were classified as low-grade and 110 as high-grade dysplasia. The results of WLI acc. to the two-tier and the three-tier Chen 2019 classifications and NBI classifications: ELS, Ni 2011, and Ni 2019 with different cut-off points were compared with the pathological examination (HP). In WLI, the greatest agreement was obtained between type 3 of the three-tier classification and high-grade dysplasia (accuracy, specificity, and PPV: 80.4%, 92.0%, and 81.5%, respectively). Assessing VFL periphery in NBI, cut-off point 5 (Ni 2011 type V) demonstrated a higher accuracy, specificity, and PPV than 4 (83.1%, 93.6%, 85.5% and 77.4%, 74.9%, and 65.4%, respectively). In NBI, we observed higher accuracy, sensitivity, and PPV (84.1%, 93.0%, 85.2% vs. 80.7%, 81.3% and 71.3%, respectively) for cut-off point 5 (Ni 2019 type V and VI) in comparison to the cut-off point 4 group (type IV, V, and VI) (80.7%, 81.3%, 71.3%, respectively), and a higher kappa value (0.68 vs. 0.58) was obtained. We have shown that both the plaque image and the microvascular pattern on the leukoplakia periphery are critical in the diagnosis of high-risk VFL. The most accurate predictor of VFL malignant transformation in WLI is type 3 according to the Chen 2019 classification, while in NBI type V and VI according to the Ni 2019 classification.

Interactive regulation of laryngeal cancer and neuroscience

Nerve fibres are distributed throughout the body along with blood and lymphatic vessels. The intrinsic morphological characteristics of nerves and the general characteristics of secretions in the tumour microenvironment provide a solid theoretical basis for exploring how neuronal tissue can influence the progression of laryngeal cancer (LC). The central nervous system (CNS) and the peripheral nervous system (PNS) jointly control many aspects of cancer and have attracted widespread attention in the study of the progression, invasion and metastasis of tumour tissue banks. Stress activates the neuroendocrine response of the human hypothalamus-pituitary-adrenal (HPA) axis. LC cells induce nerve growth in the microenvironment by releasing neurotrophic factors (NTFs), and they can also stimulate neurite formation by secreting axons and axon guides. Conversely, nerve endings secrete factors that attract LC cells; this is known as perineural invasion (PNI) and promotes the progression of the associated cancer. In this paper, we summarize the systematic understanding of the role of neuroregulation in the LC tumour microenvironment (TME) and ways in which the TME accelerates nerve growth, which is closely related to the occurrence of LC.

Current Intraoperative Imaging Techniques to Improve Surgical Resection of Laryngeal Cancer: A Systematic Review

Simple Summary

Laryngeal cancer is a prevalent head and neck malignancy, with poor prognosis and low survival rates for patients with advanced disease. The recurrence rate for advanced laryngeal cancer is between 25 and 50%. In order to improve surgical resection of laryngeal cancer and reduce local recurrence rates, various intraoperative optical imaging techniques have been investigated. In this systematic review we identify these technologies, evaluating the current state and future directions of optical imaging for this indication. Evidently, the investigated imaging modalities are generally unsuitable for deep margin assessment, and, therefore, inadequate to guide resection in advanced laryngeal disease. We discuss two optical imaging techniques that can overcome these limitations and suggest how they can be used to achieve adequate margins in laryngeal cancer at all stages.

Abstract

Laryngeal cancer is a prevalent head and neck malignancy, with poor prognosis and low survival rates for patients with advanced disease. Treatment consists of unimodal therapy through surgery or radiotherapy in early staged tumors, while advanced stage tumors are generally treated with multimodal chemoradiotherapy or (total) laryngectomy followed by radiotherapy. Still, the recurrence rate for advanced laryngeal cancer is between 25 and 50%. In order to improve surgical resection of laryngeal cancer and reduce local recurrence rates, various intraoperative optical imaging techniques have been investigated. In this systematic review, we identify these technologies, evaluating the current state and future directions of optical imaging for this indication. Narrow-band imaging (NBI) and autofluorescence (AF) are established tools for early detection of laryngeal cancer. Nonetheless, their intraoperative utility is limited by an intrinsic inability to image beyond the (sub-)mucosa. Likewise, contact endoscopy (CE) and optical coherence tomography (OCT) are technically cumbersome and only useful for mucosal margin assessment. Research on fluorescence imaging (FLI) for this application is sparse, dealing solely with nonspecific fluorescent agents. Evidently, the imaging modalities that have been investigated thus far are generally unsuitable for deep margin assessment. We discuss two optical imaging techniques that can overcome these limitations and suggest how they can be used to achieve adequate margins in laryngeal cancer at all stages.

Cyclist Effort Features: A Novel Technique for Image Texture Characterization Applied to Larynx Cancer Classification in Contact Endoscopy-Narrow Band Imaging

BACKGROUND

Feature extraction is an essential part of a Computer-Aided Diagnosis (CAD) system. It is usually preceded by a pre-processing step and followed by image classification. Usually, a large number of features is needed to end up with the desired classification results. In this work, we propose a novel approach for texture feature extraction. This method was tested on larynx Contact Endoscopy (CE)-Narrow Band Imaging (NBI) image classification to provide more objective information for otolaryngologists regarding the stage of the laryngeal cancer.

METHODS

The main idea of the proposed methods is to represent an image as a hilly surface, where different paths can be identified between a starting and an ending point. Each of these paths can be thought of as a Tour de France stage profile where a cyclist needs to perform a specific effort to arrive at the finish line. Several paths can be generated in an image where different cyclists produce an average cyclist effort representing important textural characteristics of the image. Energy and power as two Cyclist Effort Features (CyEfF) were extracted using this concept. The performance of the proposed features was evaluated for the classification of 2701 CE-NBI images into benign and malignant lesions using four supervised classifiers and subsequently compared with the performance of 24 Geometrical Features (GF) and 13 Entropy Features (EF).

RESULTS

The CyEfF features showed maximum classification accuracy of 0.882 and improved the GF classification accuracy by 3 to 12 percent. Moreover, CyEfF features were ranked as the top 10 features along with some features from GF set in two feature ranking methods.

CONCLUSION

The results prove that CyEfF with only two features can describe the textural characterization of CE-NBI images and can be part of the CAD system in combination with GF for laryngeal cancer diagnosis.

High-definition videolaryngoscopy is superior to fiberoptic laryngoscopy: a 111 multi-observer study

Purpose

This study aims to analyse differences in fiberoptic laryngoscopy (FOL) versus high definition laryngoscopy (HDL) by examining videolaryngoscopy images by a large group of observers with different levels of clinical expertise in ear, nose and throat (ENT) medicine.

Methods

This study is a 111 observer paired analysis of laryngoscopy videos during an interactive presentation. During a National Meeting of the Dutch Society of ENT/Head and Neck Surgery, observers assessed both FOL and HDL videos of nine cases with additional clinical information. Observers included 41 ENT consultants (36.9%), 34 ENT residents (30.6%), 22 researchers with Head and Neck interest (19.8%) and 14 with unspecified clinical expertise (12.6%). For both laryngoscopic techniques, sensitivity, specificity, positive and negative predictive value and diagnostic accuracy were determined for identifying a normal glottis, hyperkeratosis, radiotherapy adverse effects and squamous cell carcinoma. The sensitivities for FOL and HDL were analysed with regard to the different levels of clinical expertise.

Results

The overall sensitivity for correctly identifying the specific histological entity was higher in HDL (FOL 61% vs HDL 66.3%, p < 0.05). HDL was superior to FOL in identifying a normal glottis (FOL 68.1% vs HDL 91.6%, p < 0.01) and squamous cell carcinoma (FOL 70.86% vs HDL 79.41%, p = 0.02). Residents and researchers with Head and Neck interest diagnosed laryngeal lesions more correctly with HDL (p < 0.05).

Conclusions

In a large population of observers with different levels of clinical expertise, HDL is superior to FOL in identifying laryngeal lesions.

Evaluating Laryngopharyngeal Tumor Extension Using Narrow Band Imaging Versus Conventional White Light Imaging

OBJECTIVE/HYPOTHESIS

Comparing detection and extension of malignant tumors by flexible laryngoscopy in the outpatient setting with laryngoscopy under general anesthesia using both White Light Imaging (WLI) and Narrow Band Imaging (NBI).

STUDY DESIGN

Prospective study.

METHODS

Two hundred and thirty-three patients with laryngeal and pharyngeal lesions underwent flexible and rigid laryngoscopy, with both WLI and NBI. Extension of malignant lesions (n = 132) was compared between both techniques in detail.

RESULTS

Sensitivity of NBI during flexible endoscopy (92%), was comparable with that of WLI during rigid endoscopy (91%). The correlation of tumor extension between flexible and rigid laryngoscopy was high (r_s  = 0.852-0.893). The observed tumor extension was significantly larger when using NBI in both settings. The use of NBI during flexible laryngoscopy leads to upstaging (12%) and downstaging (2%) of the T classification.

CONCLUSIONS

NBI during flexible laryngoscopy could be an alternative to WLI rigid endoscopy. NBI improves visualization of tumor extension and accuracy of T staging.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:E2222-E2231, 2021.

Laryngeal Lesion Classification Based on Vascular Patterns in Contact Endoscopy and Narrow Band Imaging: Manual Versus Automatic Approach

Longitudinal and perpendicular changes in the vocal fold’s blood vessels are associated with the development of benign and malignant laryngeal lesions. The combination of Contact Endoscopy (CE) and Narrow Band Imaging (NBI) can provide intraoperative real-time visualization of the vascular changes in the laryngeal mucosa. However, the visual evaluation of vascular patterns in CE-NBI images is challenging and highly depends on the clinicians’ experience. The current study aims to evaluate and compare the performance of a manual and an automatic approach for laryngeal lesion’s classification based on vascular patterns in CE-NBI images. In the manual approach, six observers visually evaluated a series of CE+NBI images that belong to a patient and then classified the patient as benign or malignant. For the automatic classification, an algorithm based on characterizing the level of the vessel’s disorder in combination with four supervised classifiers was used to classify CE-NBI images. The results showed that the manual approach’s subjective evaluation could be reduced by using a computer-based approach. Moreover, the automatic approach showed the potential to work as an assistant system in case of disagreements among clinicians and to reduce the manual approach’s misclassification issue.

Incidence and malignant transformation of glottic precursor lesions in Denmark

Objectives: Glottic precursor lesion (GPL) is a well-known premalignant condition, but the existing knowledge of incidence and malignant potential is based on subpopulation studies. In this first, nationwide study we report data from all verified cases of GPL in Denmark during a 10-year period with focus on incidence and malignant transformation of GPL.Methods: Patients were identified by a search for GPL in the time period from 01.01.2000 to 31.12.2009 using the Danish Pathology Data Base, Patobank, which is a nationwide source of all cyto- and histopathological data obtained in Denmark. Data were validated and supplemented by medical chart review.Results: A 10-year national cohort of 965 patients (median age 60 years, male-female ratio 2:1) with histologically verified GPL was analyzed. The overall malignant transformation rate was 18.3% (mild dysplasia 7.7%, moderate dysplasia 19.8%, severe dysplasia 28.5%, and carcinoma in situ 40.3%) with a median progression time of 29 months. Eighty-eight percent of patients were active or former smokers. A significantly larger proportion of male patients (24.1%) experienced malignant transformation compared to females (6.6%) (p < .001).Conclusion: This nationwide population-based study of GPL patients confirmed a stable incidence of GPL in Denmark from January 2000 to December 2009 and a considerable malignant potential, correlated to the grading of GPL according to the World Health Organization classification of laryngeal precursor lesions from 2005, WHOC2005. The recent update, WHOC2017, of low-grade versus high-grade lesions may thus contain less nuanced prognostic information than WHOC2005.Level of evidence: 2b retrospective cohort study.

A Preliminary Study on Automatic Characterization and Classification of Vascular Patterns of Contact Endoscopy Images

The structure and organization of blood vessels in the vocal fold go through changes during the advancement from healthy to benign and further on to malignant stages. Contact Endoscopy (CE) is an optical technique providing real-time information related to the vascular structure of laryngeal mucosa. However, this technique comes with subjectivity in the interpretation of vascular patterns. In this study, a novel automated approach is proposed for vessel pattern charac-terization and classification of larynx CE + Narrow Band Imaging (NBI) images. This method is mainly based on the computation of indicators related to the level of disorder of vessels. 12 features were extracted from the indicators and were fed into two supervised classifiers. Linear Support Vector Machine (SVM) and K-Nearest Neighbor (KNN) showed an accuracy of 95.76% and 93.92% for vascular patterns and 86.04% and 82.23% for larynx histopathologies classification, respectively. These promising results show that the proposed method can potentially solve the subjectivity issues of CE.

Interrater variation of vascular classifications used in enhanced laryngeal contact endoscopy

PURPOSE

Combined use of contact endoscopy (CE) and Narrow Band Imaging (NBI, Olympus^®) is suggested for the visualization of specific vascular changes indicative of glottic neoplasia. We investigated the interrater reliability and agreement in 3 recognized classification systems of vascular changes applied to images from CE + NBI in patients suspected for glottic neoplasia.

METHODS

Six experienced head and neck surgeons familiar with NBI rated 120 images obtained by CE + NBI by 3 classification systems of vascular changes as suggested by Ni et al. (N-C), Puxeddu et al. (P-C), and the European Laryngological Society (ELS-C). Three raters were experienced in CE, and three raters had only limited experience with CE. Crude agreement and Fleiss' kappa with 95% confidence interval were estimated for all 6 raters, and for the 2 levels of expertise for each original classification system and for dichotomized versions of the N-C and the P-C based on suggested neoplastic potential.

RESULTS

The interrater crude agreement and the corresponding kappa values for the ELS-C were good and significantly higher than those for the N-C and P-C for all raters, irrespective of the level of experience with CE (p < 0.0001). There were no significant differences between the N-C and the P-C (p = 0.16). Kappa was considerably improved for both the N-C and the P-C to a level not different from the ELS-C (p = 0.21-0.71) when their 5 original categories were pooled into dichotomized classifications.

CONCLUSION

Difficulties in reliably classifying vascular changes in CE + NBI are evident. Two-tier classification systems are the most reliable.

Loss of Estrogen Receptors is Associated with Increased Tumor Aggression in Laryngeal Squamous Cell Carcinoma

Laryngeal squamous cell carcinoma (LSCC) responds to 17β-estradiol via estrogen-receptor (ER, transcribed from ESR1) dependent mechanisms, but is not recognized as a hormonally responsive cancer. 17β-estradiol production by LSCC cell lines UM-SCC-11A and UM-SCC-12 was examined. Wild type (WT) and ESR1-silenced LSCC cultures and xenografts were examined for 17β-estradiol responsiveness in vivo. 14 LSCC and surrounding epithelial samples at various pathological stages were obtained from patients; ERα and ERβ expression were verified using data from the total cancer genome atlas. UM-SCC-11A and UM-SCC-12 both produce 17β-estradiol, but only UM-SCC-12, not UM-SCC-11A, xenograft tumors grow larger in vivo in response to systemic 17β-estradiol treatments. ERα66 and ERα36 expression inversely correlated with clinical cancer stage and tumor burden. LSCC ERα66 expression was higher compared to surrounding epithelia in indolent samples but lower in aggressive LSCC. ERβ expression was highly variable. High ESR1 expression correlated with improved survival in LSCC. Loss of ERα66 expression inversely correlated with prognosis in LSCC. ERα66 may be a histopathological marker of aggression in LSCC.

Vocal-fold leukoplakia and dysplasia. Mini-review by the French Society of Phoniatrics and Laryngology (SFPL)

Vocal-fold leukoplakia and dysplasia are together designated "epithelial hyperplastic laryngeal lesions" (EHLL). Work-up and follow-up are founded on optical examination with high-definition imaging, stroboscopy and narrow-band imaging. Diagnosis is based on pathology, using the new 2017 WHO classification, dichotomizing "low grade" and "high grade". Statistically, the risk of cancerous progression is 20% within 5 to 10 years of diagnosis, or more in over-65 year-old males; risk for any given patient, however, is unpredictable. Research focuses on the genetic criteria of the lesion and characterization of the tumoral microenvironment. Treatment is exclusively microsurgical. Resection depth is adjusted according to infiltration. EHLL is a chronic disease, necessitating long-term follow-up, which may be hampered by residual dysphonia and surgical sequelae in the vocal folds. Sequelae need to be minimized by good mastery of microsurgical technique and indications. When they occur, biomaterials such as autologous fat and hyaluronic acid can be useful. Tissue bio-engineering is a promising field.

Evaluation of Vascular Patterns Using Contact Endoscopy and Narrow-Band Imaging (CE-NBI) for the Diagnosis of Vocal Fold Malignancy

The endoscopic detection of perpendicular vascular changes (PVC) of the vocal folds has been associated with vocal fold cancer, dysplastic lesions, and papillomatosis, according to a classification proposed by the European Laryngological Society (ELS). The combination of contact endoscopy with narrow-band imaging (NBI-CE) allows intraoperatively a highly contrasted, real-time visualization of vascular changes of the vocal folds. Aim of the present study was to determine the association of PVC to specific histological diagnoses, the level of interobserver agreement in the detection of PVC, and their diagnostic effectiveness in diagnosing laryngeal malignancy. The evaluation of our data confirmed the association of PVC to vocal fold cancer, dysplastic lesions, and papillomatosis. The level of agreement between the observers in the identification of PVC was moderate for the less-experienced observers and almost perfect for the experienced observers. The identification of PVC during NBI-CE proved to be a valuable indicator for diagnosing malignant and premalignant lesions.

Differences in the diagnostic value between fiberoptic and high definition laryngoscopy for the characterisation of pharyngeal and laryngeal lesions: A multi-observer paired analysis of videos

OBJECTIVES

High definition laryngoscopy (HDL) could lead to better interpretation of the pharyngeal and laryngeal mucosa than regularly used fiberoptic laryngoscopy (FOL). The primary aim of this study is to quantify the diagnostic advantage of HDL over FOL in detecting mucosal anomalies in general, in differentiating malignant from benign lesions and in predicting specific histological entities. The secondary aim is to analyse image quality of both laryngoscopes.

DESIGN

Retrospective paired analysis with multiple observers evaluating endoscopic videos simulating daily clinical practice.

SETTING

A tertiary referral hospital.

PARTICIPANTS

In 36 patients, both FOL and HDL videos were obtained. Six observers were provided with additional clinical information, and 36 FOL and HDL videos were evaluated in a randomised order.

MAIN OUTCOME MEASURES

Sensitivity, specificity, positive and negative predictive value and diagnostic accuracy of observers using both flexible laryngoscopes were calculated for detection of mucosal lesions in general and uncovering malignant lesions. Sensitivities were calculated for prediction of specific histological entities. Image quality (scale 1-10) was assessed for both flexible laryngoscopes.

RESULTS

HDL reached higher sensitivity compared to FOL for detection of mucosal abnormalities in general (96.0% vs 90.4%; P = .03), differentiating malignant from benign lesions (91.7% vs 79.8%; P = .03) and prediction of specific histological entities (59.7% vs 47.2%; P < .01). Image quality was judged better with HDL in comparison with FOL (mean: 8.4 vs 5.4, P < .01).

CONCLUSIONS

HDL is superior to FOL in detecting mucosal anomalies in general, malignancies and specific histological entities. Image quality is considered as superior using HDL compared to FOL.

Laser induced autofluorescence lifetime to identify larynx squamous cell carcinoma: Short series ex vivo study

Laser induced autofluorescence (LIAF) lifetime is useful to distinguish between normal laryngeal tissues and squamous cell carcinoma (SCC) based on variations of their biochemical composition and structure alterations. LIAF was collected from samples constituted by pairs of normal and malignant tissue, which were excised from three patients. Exclusion criteria for samples harvest were: (i) macroscopic changes of normal vocal cord observed during surgery; (ii) previous surgical intervention on vocal cord, (iii) patients treated only with chemotherapy or radiotherapy for carcinoma. Inclusion conditions: men, aged 57-68, non-smokers. A pulsed laser diode excited LIAF at 375 nm and 31 MHz repetition rate; beam full-time width at half-maximum was 87 ps at an average power of 0.49 mW. Mean LIAF lifetime for normal tissues was (3.75 ± 0.49) ns and for malignant (4.37 ± 0.85) ns: it is longer in malignant than in normal tissue. Variance analysis made with Fisher's test has shown no significant difference between patients for normal tissues; the same was true for malignant. Though, when malignant tissue was compared to normal for the same patients as well as between patients, a significant difference (significance level of 5%) was evidenced. Time-resolved LIAF may allow better differentiation between normal and malignant tissues in patients diagnosed with larynx SCC.

Value of pre- and intraoperative diagnostic methods in suspected glottic neoplasia

PURPOSE

To evaluate the individual and combined ability of videostroboscopy (VS), high-speed digital imaging (HSDI), enhanced endoscopy (EE) and saline infusion (SI) to predict neoplasia, defined as glottic precursor lesion (GPL) or T1a glottic cancer, in patients suspected for glottic neoplasia.

METHODS

A nationwide prospective cohort study of patients treated by cordectomy for suspected GPL or T1a glottic cancer from August 1st 2016 to October 31st 2018 was conducted in the five Danish University Departments of Head and Neck surgery. Sensitivity, specificity, negative and positive predictive values, and area under Receiver Operating Curves (AUC-ROC) were calculated with 95% confidence intervals with respect to the histological diagnosis. Logistic regression with an imputation model for missing data was applied.

RESULTS

261 patients aged 34-91 years participated; 79 (30.3%) with non-neoplasia (i.e., inflammation, papilloma, hyperkeratosis) and 182 (69.7%) neoplasia, hereof 95 (36.4%) with GPL and 87 (33.3%) with T1a glottic cancer. Data from 188 VS, 60 HSDI, 100 preoperative EE, 209 intraoperative EE, and 234 SI were analyzed. In the complete case analysis the AUC-ROC of each diagnostic test was low, but increased when the tests were combined and especially if the combination included EE. However, multinomial logistic regression with imputation showed significant association (p < 0.05) only between age, male gender, and perpendicular vasculature in intraoperative EE, and the endpoint neoplasia.

CONCLUSIONS

Intraoperative EE was the most accurate diagnostic method in detecting neoplasia. The prediction ability of methods applied preoperatively was more limited, but improved when test modalities were combined.

GLUT-1 participates in the promotion of LncRNA CASC9 in proliferation and metastasis of laryngeal carcinoma cells

Increasing evidence indicates that long non-coding RNA (lncRNA) may play important roles in tumorigenesis. Increased lncRNA CASC9 occurs in laryngeal carcinoma, which accounts for 20% of all head and neck cancers, but its role in this disease remains unknown. Using quantitative reverse transcriptase PCR, we found higher expression of CASC9 and GLUT-1 in laryngeal carcinoma tissues and cells, compared to adjacent tissues and cells. A correlation analysis showed a positive relationship between CASC9 and GLUT-1 expression in laryngeal carcinoma tissues. An MTT assay of TU212 and Hep-2 cells showed increased cell proliferation after transfection with overexpressed CASC9 and decreased cell proliferation after transfection with silenced CASC9. A Transwell assay showed that overexpressing CASC9 increased and silencing CASC9 decreased cell migration of TU212 and Hep-2 cells. A flow cytometry assay showed that overexpressing CASC9 reduced and silencing CASC9 increased cell apoptosis. In other words, we found that overexpressing CASC9 increased cell proliferation and cell migration and decreased apoptosis both in TU212 and Hep-2 cells, whereas silencing CASC9 had the opposite effects. Moreover, overexpression vector of GLUT-1 was used to investigate the molecular mechanism of CASC9 in laryngeal carcinoma. The results showed that transfection with an overexpressed GLUT-1vector reversed the effects of silencing CASC9 on proliferation, migration, and apoptosis in TU212 and Hep-2 cells. In conclusion, our study of laryngeal carcinoma found that CASC9 was positively correlated with GLUT-1 expression and that CASC9 may promote proliferation and metastasis of laryngeal carcinoma cells by regulating GLUT-1.

High levels of ANXA2 are characteristic of malignant salivary gland tumors

OBJECTIVE

Malignant salivary gland tumors (MSGTs) present different phenotypic characteristics and various clinical outcomes, which proved to be a diagnostic challenge. Considering the heterogeneity of MSGT, this study aims to identify molecule related to the nature of MSGT.

METHODS

For screening, proteomic analysis comparing MSGT with pleomorphic adenoma (PA) and salivary gland was performed. The MSGT-associated protein which presented in the higher number in the Gene Expression Omnibus (GEO) database was selected. To validate the data, immunohistochemistry (IHC) was performed in 14 patients with PA, 22 patients with MSGT, and 14 controls.

RESULTS

16 proteins were associated with MSGT. ANXA2 was the primary protein, according to GEO database analyses. ANXA2 was most expressed in the cell membrane. However, some ANXA2 staining was also observed in the cytoplasm and nucleus. ANXA2 was highly expressed in MSGT in comparison with control. Also, ANXA2 has a higher expression in adenocarcinoma not otherwise specified (ANOS) and myoepithelial carcinoma (MC) in comparison with PA.

CONCLUSION

In conclusion, this study demonstrated that MSGT presented higher levels of ANXA2 in comparison with normal salivary glands. Also, ANXA2 might be interesting as a molecular marker of ANOS and MS.

Novel automated vessel pattern characterization of larynx contact endoscopic video images

Purpose

Contact endoscopy (CE) is a minimally invasive procedure providing real-time information about the cellular and vascular structure of the superficial layer of laryngeal mucosa. This method can be combined with optical enhancement methods such as narrow band imaging (NBI). However, these techniques have some problems like subjective interpretation of vascular patterns and difficulty in differentiation between benign and malignant lesions. We propose a novel automated approach for vessel pattern characterization of larynx CE + NBI images in order to solve these problems.

Methods

In this approach, five indicators were computed to characterize the level of vessel’s disorder based on evaluation of consistency of gradient and two-dimensional curvature analysis and then 24 features were extracted from these indicators. The method evaluated the ability of the extracted features to classify CE + NBI images based on the vascular pattern and based on the laryngeal lesions. Four datasets were generated from 32 patients involving 1485 images. The classification scenarios were implemented using four supervised classifiers.

Results

For classification of CE + NBI images based on the vascular pattern, polykernel support vector machine (SVM), SVM with radial basis function (RBF), k-nearest neighbor (kNN), and random forest (RF) show an accuracy of 97%, 96%, 96%, and 96%, respectively. For the classification based on the histopathology, Polykernel SVM showed an accuracy of 84%, 86% and 84%, RBF SVM showed an accuracy of 81%, 87% and 83%, kNN showed an accuracy of 89%, 87%, 91%, RF showed an accuracy of 90%, 88% and 91% for classification between benign histopathologies, between malignant histopathologies and between benign and malignant lesions, respectively.

Conclusion

These promising results show that the proposed method could solve the problem of subjectivity in interpretation of vascular patterns and also support the clinicians in the early detection of benign, pre-malignant and malignant lesions.

The White Lesion, Hyperkeratosis, and Dysplasia

Laryngeal mucosal precursor lesions represent a challenging clinical entity. Updated classification systems allow for grade-based categorization. Multiple management options exist, with treatment decisions made jointly by physician and patient and focused on both appropriate lesion treatment and preservation of laryngeal structure and function. Traditional methods include cold steel and CO₂ laser excision, with newer modalities using angiolytic lasers for lesion ablation. Both operating room-based and office-based treatment options exist, and there are advantages and disadvantages to each approach. Research is ongoing to advance the understanding of lesion biology, and to optimize prevention and treatment.

Magnetic resonance imaging of the larynx in the pediatric population: A systematic review

BACKGROUND

Magnetic Resonance Imaging (MRI) techniques to image the larynx have evolved rapidly into a promising and safe imaging modality, without need for sedation or ionizing radiation. MRI is therefore of great interest to image pediatric laryngeal diseases. Our aim was to review MRI developments relevant for the pediatric larynx and to discuss future imaging options.

METHODS

A systematic search was conducted to identify all morphological and diagnostic studies in which MRI was used to image the pediatric larynx, laryngeal disease, or vocal cords.

RESULTS

Fourteen articles were included: three studies on anatomical imaging of the larynx, two studies on Diffusion Weighted Imaging, four studies on vocal cord imaging and five studies on the effect of anaesthesiology on the pediatric larynx. MRI has been used for pediatric laryngeal imaging since 1991. MRI provides excellent soft tissue contrast and good visualization of vascular diseases such as haemangiomas. However, visualization of cartilaginous structures, with varying ossification during childhood, and tissue differentiation remain challenging. The latter has been partly overcome with diffusion weighted imaging (DWI), differentiating between benign and malignant masses with excellent sensitivity (94-94.4%) and specificity (91.2-100%). Vocal cord imaging evolved from static images focused on vocal tract growth to dynamic images able to detect abnormal vocal cord movement.

CONCLUSION

MRI is promising to evaluate the pediatric larynx, but studies using MRI as diagnostic imaging modality are scarce. New static and dynamic MR imaging techniques could be implemented in the pediatric population. Further research on imaging of pediatric laryngeal diseases should be conducted.

Flexible transnasal endoscopy with white light or narrow band imaging for the diagnosis of laryngeal malignancy: diagnostic value, observer variability and influence of previous laryngeal surgery

Purpose

Flexible transnasal endoscopy is a common examination technique for the evaluation of laryngeal lesions, while the use of narrow band imaging (NBI) has been reported to enhance the diagnostic value of white light endoscopy (WLE). The purpose of this study is to assess observer variability and diagnostic value of both modalities and investigate the possible influence of previous laryngeal surgery on the detection rates of laryngeal malignancy.

Methods

The study was based on the retrospective evaluation of 170 WLE and NBI images of laryngeal lesions by three observers in a random order. The histopathological diagnoses serve as the gold standard.

Results

In identifying laryngeal malignancy, the sensitivity of NBI proved to be higher than that of WLE (93.3% vs. 77.0%). NBI was also superior to WLE in terms of accuracy (96.3% vs. 92%) and diagnostic odds ratio (501.83 vs. 120.65). Both modalities had a specificity of 97.3%. The inter-observer agreement was substantial (kappa = 0.661) for WLE and almost perfect (kappa = 0.849) for NBI. Both WLE and NBI showed a high level of intra-observer agreement. The sensitivity was significantly lower in images with history of previous laryngeal surgery compared to those without.

Conclusions

Flexible transnasal endoscopy has been proved to be a valuable tool in the diagnosis of laryngeal malignancy. The use of NBI can increase the sensitivity and observer reliability in that context and can also provide a diagnostic gain in cases with previous laryngeal surgery

Phonosurgical Resection Using Submucosal Infusion Technique for Early Glottic Lesions: Diagnostic and Therapeutic Procedure?

OBJECTIVES:

The aim of this study was to assess the feasibility of the submucosal infusion combined with microflap dissection via laser CO2 as both a diagnostic and therapeutic procedure for superficial glottic lesions. To define a safe surgical procedure in terms of local control, a morphometric study of surgical margins was performed.

METHODS:

From January 2011 to January 2016, we treated 122 patients with early glottic lesions with phonomicrosurgery. Patients with effective hydrodissection underwent a microflap and type I-II diagnostic cordectomy. In the others, a biopsy was carried out, and in the case of a malignant lesion, a type III to VI cordectomy was performed. Disease-free survival (DFS) for all the lesions was also determined according to comparative assessments of surgical margins. The Voice Handicap Index was used to evaluate functional outcomes.

RESULTS:

In 27 cases (32%), hydrodissection was effective; specifically, 24 (88.8%) were premalignant lesions, and 3 (11.2%) had a carcinoma. In 56 patients (68%), hydrodissection was not adequate, and a biopsy was performed: 9 (16%) were premalignant and 47 (84%) malignant lesions. The DFS analysis suggests that margins >0.7 mm resulted in a cutoff that can guarantee a safe procedure in the case of effective hydrodissection ( P < .05).

CONCLUSION:

Phonomicrosurgery may be both a diagnostic and therapeutic option with oncological efficacy for superficial glottic lesions of undetermined nature when surgical margins exceed 0.7 mm. In case of inadequate hydrodissection, the hypothesis of an infiltrative carcinoma warrants a wider cordectomy.

Correlating laryngoscopic appearance of laryngeal lesions with histopathology

OBJECTIVES/HYPOTHESIS

Meticulous scrutiny of laryngeal lesions with laryngoscopes and microscopes often identify angiogenic activity, one of the hallmarks of neoplastic and preneoplastic lesions. The aim of this study was to determine if there is an association between laryngoscopic appearance and histopathology of laryngeal lesions based on operative biopsies.

STUDY DESIGN

Retrospective case-control study.

METHODS

One hundred forty-four laryngeal biopsies from 92 patients between 2015 and 2017 met inclusion criteria. Cases were patients who had biopsy-proven laryngeal dysplasia or malignancy. Controls were patients who had benign laryngeal pathology. All of the laryngeal lesions had either keratosis or vascular stippling, an indication of angiogenic activity. Medical records, videostroboscopies and operative findings of these patients were reviewed. Multivariable logistic regression was used to examine the correlation between laryngoscopic appearance of laryngeal lesions and presence or absence of dysplasia and invasive carcinoma.

RESULTS

Fifty percent of the 144 laryngeal lesions were classified either as dysplastic or malignant by histopathology. Vascular stippling was present in 31% of all laryngeal lesions. On logistic regression, vascular stippling was significantly associated with dysplastic and malignant lesions (P = .0018). Overall sensitivity and specificity of vascular stippling and the presence of dysplasia and malignancy were 51% and 89%, respectively.

CONCLUSIONS

Laryngoscopic and microscopic appearance of vascular stippling could inform clinicians on diagnostic sampling of suspicious laryngeal lesions that reduces delay in diagnosis. The low sensitivity of vascular stippling underlies the importance of maintaining high clinical suspicion and proceeding to the operating theater for adequate tissue sampling.

LEVEL OF EVIDENCE

3 Laryngoscope, 129:1308-1312, 2019.

Development of three-dimensional laryngostroboscopy for office-based laryngeal diagnostics and phonosurgical therapy

OBJECTIVE

To develop a three-dimensional (3D) laryngostroboscopic examination unit, compare the optic playback quality in relation to established 2D procedures, and report the first case series using 3D rigid laryngostroboscopy for diagnosis and management of laryngotracheal diseases.

STUDY DESIGN

Laboratory study, prospective case series.

METHODS

The optical efficacy of newly developed rigid 3D endoscopes was examined in a laboratory setting. Diagnostic suitability was investigated in 100 subjects (50 male, 50 female) receiving 2D high-definition (HD) and 3D laryngostroboscopy. Two of the subjects subsequently underwent 3D-assisted office-based transoral phonosurgery under local anesthesia. Main outcome measures were comparative visualization of laryngotracheal pathologies, influence on preoperative planning, and evaluation of prognostic factors for the outcome of phonosurgical interventions.

RESULTS

Three-dimensional endostroboscopic procedures were effectively optimized to establish an examination protocol for all-day clinical use. Office-based 3D laryngostroboscopy was successfully applied in subjects with normal anatomy (n = 10) and various laryngotracheal findings (n = 90). In comparison to 2D HD videolaryngostroboscopy, the 3D view offered enhanced visualization of laryngotracheal anatomy, with qualitatively improved depth perception and spatial representation. In organic pathologies, this resulted in a more precise indication of phonosurgical procedures, increased accuracy in surgical planning, facilitated office-based endoscopic surgery, and better evaluation of prognostic factors for the outcome of phonosurgical interventions.

CONCLUSION

Three-dimensional laryngostroboscopy proved to increase the understanding of functional and surgical anatomy. Its application has enormous potential for improving the diagnostic value of laryngoscopy, surgical precision in laryngotracheal interventions, tissue preservation, and methods of teaching.

LEVEL OF EVIDENCE

NA Laryngoscope, 128:2823-2831, 2018.

Proposal of a form for the collection of videolaryngostroboscopy basic findings

Videolaryngostroboscopy is a useful investigation required for a correct diagnosis of laryngeal diseases and voice disorders. We present a form for the collection of basic laryngostroboscopic findings, which provides for the evaluation of the classical six parameters codified by Hirano (symmetry and periodicity of glottic vibration, glottic closure, profile of vocal fold edge, amplitude of vocal fold vibration, mucosal wave) and six other parameters which we have included in the form for an essential and complete laryngostroboscopic evaluation (supraglottic framework behaviour, seat of phonatory vibration, vocal fold morphology and motility, level of the vocal fold, stops of vocal fold mucosa vibration). This form was created in 2002 during the elaboration of the protocol for the assessment of dysphonia of the Italian Society of Phoniatrics and Logopedics, which follows the guidelines of the European Laryngological Society published in 2001. We used this form for 15 years in our daily laryngological practice with great satisfaction. We propose a more detailed version of this form, which provides for drawings which show the various videolaryngostroboscopic findings, helping the laryngologist in the collection of videolaryngostroboscopic examination basic findings.

The value of narrow band imaging combined with stroboscopy for the detection of applanate indiscernible early-stage vocal cord cancer

BACKGROUND

Narrow band imaging (NBI) and stroboscopy are non-invasive techniques to detect the malignant lesions of the vocal cord. This study was to assess the diagnostic value of combined endoscopic analysis in the applanate indiscernible early-stage vocal cord cancer.

METHODS

A total of 110 patients with 160 suspicious vocal cord malignant lesions were included in this retrospective study. Stroboscopy was immediately performed after NBI and white light endoscopy (WLE) were performed in all patients. Excisional biopsy was performed to examine histopathology examination.

RESULTS

We found that the diagnostic specificity and PPV were higher in the NBI and WLE combined with stroboscopy group than in the NBI and WLE group without stroboscopy (88.9% vs 72.5%, 88.4% vs 60.9%). However, the diagnostic sensitivity was not significantly different in those two groups (69.3% vs 67.7%).

CONCLUSION

NBI and WLE combined with stroboscopy is a promising method to detect early-stage vocal cord cancer with the advantage of clinical feasibility and diagnostic specificity.

The value of narrow band imaging in diagnosis of head and neck cancer: a meta-analysis

Head and neck cancer is difficult to diagnose early. We aimed to estimate the diagnosis value of narrow band imaging(NBI) in head and neck cancers. We identified relevant studies through a search of PubMed, Embase and the Cochrane Library. We used a random effect model. Subgroup analysis and meta-regression analysis were performed to estimate the factors which may influence the sensitivity and specificity of the NBI. We included 25 studies with total 6187 lesions. The pooled sensitivity, specificity, positive likelihood rate, negative likelihood rate and diagnostic odds ratios of NBI were 88.5%, 95.6%, 12.33, 0.11 and 121.26, respectively. The overall area under the curve of SROC was 96.94%. The location, type of assessment, type of endoscope system and high definition were not significant sources of heterogeneity (P > 0.05). However, magnification may be related to the source of heterogeneity (P = 0.0065). Therefore, NBI may be a promising endoscopic tool in the diagnosis of head and neck cancer.

Annexin A2 is an independent prognostic biomarker for evaluating the malignant progression of laryngeal cancer

Due to the lack of a definite diagnosis, a frequent recurrence rate and resistance to chemotherapy or radiotherapy, the clinical outcome for patients with advanced laryngeal cancer has not improved over the last decade. Annexin A2 is associated with the invasion and metastasis of cancer cells. In the present study, it was demonstrated using differential proteomics analysis that Annexin A2 is highly expressed in laryngeal carcinoma tissues and this was confirmed using immunohistochemistry, which demonstrated that the expression of Annexin A2 in laryngeal carcinoma tissues was significantly higher than in healthy adjacent tissue. In addition, its potential predictive value in the prognosis of patients with laryngeal carcinoma was evaluated. The results demonstrated that Annexin A2 expression was significantly associated with tumor size, lymph node metastasis, distant metastasis and clinical stage. In addition, higher Annexin A2 expression was associated with a poor prognosis of patients with laryngeal cancer. Thus, the results of the present study indicate that Annexin A2 expression is an independent prognostic biomarker for evaluating the malignant progression of laryngeal cancer.

The tissue distribution and significance of B7-H4 in laryngeal carcinoma

The costimulatory signals CD28 and B7 have been shown to control tumor invasion and metastasis by regulating T cell activation, whereas the distribution characteristics of B7-associated proteins in laryngeal carcinoma (LC) tissue are still unclear. Here, the expression of members of the B7 superfamily, including B7-H1 (PD-L1), B7-DC (PD-L2) and B7-H4, in fifty-two LC samples was determined by immunohistochemistry, and the relationship between B7-H4 and epithelial-mesenchymal transition (EMT)-associated markers was further assessed by immunofluorescence double staining. Furthermore, the human LC cell lines, Hep-2 and TU212 cells, were further transfected to overexpress B7-H4, and cell invasion and metastasis were analyzed. The results showed that B7-H1, B7-DC and B7-H4 were expressed in the tumor cells, and their expression was restricted to the cell membrane and the cytoplasm. The positive rates of these molecules in the tumor tissues were 57.7% (30/52), 32.7% (17/52) and 34.6% (18/52), respectively. Interestingly, double immunofluorescence staining showed that B7-H4 is coexpression with EMT-related markers, including p-Smad2/3, Snail and Vimentin, in carcinoma cells. Moreover, overexpression of B7-H4 in Hep-2 cells promotes the expression of pSmad2/3 and Snail by activating AKT-STAT3 signaling. Transwell and wound-healing assays demonstrated that B7-H4 enhanced both Hep-2 and TU212 cell invasion and metastasis. Our results suggest that B7-H4 transmits feedback signaling to tumor cells and promotes invasion and metastasis by promoting EMT progression. Therefore, blocking B7-H4 signaling might be a novel treatment strategy for LC.