The value of narrowband imaging using the Ni classification in the diagnosis of laryngeal cancer

Binary Classification of Laryngeal Images Utilising ResNet-50 CNN Architecture

In India, laryngeal cancer is a significant health concern, underlining the critical need for early detection methods. This study introduces a novel approach to classify laryngeal lesions into nine morphological categories; due to data scarcity for all the nine classes, the data is divided into cancer and non-cancer classes, including both non-cancerous and Squamous Cell Carcinoma (SCC), by analysing endoscopy images with advanced convolutional neural networks, deep learning, and image processing techniques. A dataset of 1978 endoscopy images from 960 patients at a tertiary care center in Lucknow, between May 2015 and December 2023, was utilised for this purpose. These images, captured using an Olympus CV-170 processor and annotated via the CVAT tool, were processed to highlight Regions of Interest (ROI) for detailed examination. The dataset was split, with 90% for training/validation and 10% for testing. A total of 197 images out of 1978 were selected for testing, which included 43 cancerous and 154 non-cancerous images. For the feature extraction, ResNet50 was utilised. The model's evaluation through the Receiver Operating Characteristic (ROC) curve demonstrated high effectiveness, with areas of 0.95, 0.98, and 0.93 for combined, NBI-only, and WL-only datasets, respectively. The accuracy rates were notably high across all datasets, highlighting the potential of this model to significantly aid in the early detection and classification of laryngeal cancer. In India, where the incidence of head and neck cancer is high and there is a lack of both advanced instruments and expertise in Narrow Band Imaging (NBI), this model could be instrumental in the early detection of laryngopharyngeal cancer. Level of Evidence: 2 C.

Laryngeal Carcinoma Characteristics Associated with Positive Margins and Endoscopic Understaging

Background/Objectives: The study aims to analyse the factors associated with positive margins and endoscopic understaging in laryngeal carcinoma. It also aims to assess the diagnostic accuracy of Narrow Band Imaging (NBI) in comparison to White Light Endoscopy (WLE) and other diagnostic methods. Methods: In this retrospective comparative cohort analysis, 206 patients who underwent endoscopic laser surgery for T1 and T2a glottic squamous cell carcinoma between 1 January 2016 and 30 April 2023 were included. The data were collected from endoscopy, CT, histopathology, and NBI images. Statistical analysis was performed and associations between variables were analysed using binary logistic regression and receiver operating characteristic analysis. Results: The types of cordectomy performed included type III (51 patients), type IV (40 patients), and type VI (23 patients). Positive margins were found in 14.01% of patients, with significant correlations observed between positive margins and bilateral laryngeal carcinoma, right-sided laryngeal carcinoma, higher clinical and histopathologic T categories, and higher NBI grade. Endoscopic understaging versus histopathologic T category correlated with various factors, including cordectomy type, tumour size, and clinical T category. The NBI findings correlated with positive margins but did not correlate with endoscopic understaging. Conclusions: The study highlights several clinical and pathological factors associated with positive margins and endoscopic understaging in laryngeal carcinoma. NBI demonstrated high diagnostic accuracy, correlating with histopathological results and serving as an independent predictive factor for positive margins. Recognizing these factors is crucial for improving preoperative assessments, refining treatment strategies, and enhancing patient care.

Correlation of Narrow Band Imaging Patterns with Histopathology Reports in Head and Neck Lesions

Introduction

Head and neck malignancies are associated with poor prognosis and poor quality-of-life if detected late. Narrow-Band-Imaging(NBI) is one of the important tools, which helps in detecting these lesions earlier. By using narrow-wavelength(400-550 nm) it enhances the mucosal and submucosal vascularity against the pale mucosal background which helps us detecting benign, pre-malignant and malignant lesions.

Objective

The objective of this study was to evaluate the accuracy of NBI in the diagnosis of various mucosal lesions of head and neck region and its correlation with the histopathology reports.

Materials and Methods

This was a prospective diagnostic study conducted between June 2020 - June 2022 where 118 patients(oral cavity-28, laryngeal-87,and hypopharyngeal-3) who fulfilled the inclusion and exclusion criteria were recruited. All-118-patients underwent NBI endoscopy under local/general anaesthesia followed by biopsies from the most suspicious-areas. Type of vascular-pattern noted from NBI and their respective histopathological reports were correlated.

Results

The mean age was 53.28 ± 1.24 years ranging from 16 to 88 years. The sensitivity, specificity, Positive-Predictive-Value(PPV) and Negative-Predictive-Value(NPV) in detecting benign lesions were 100%, 90%, 74% and 100% respectively. The sensitivity, specificity, PPV and NPV in detecting premalignant lesions were 70%, 92%, 56% and 96% respectively. The sensitivity, specificity, PPV and NPV in detecting malignant lesions were 83%,97.5%, 98.5% and 97.5% respectively. NBI has a strong association with the histopathological reports, which is statistically significant(p-value < 0.001).

Conclusion

NBI has high specificity and negative predictive value in detecting and classifying various mucosal lesions of head-neck region. Its findings had a strong correlation with histopathological reports.

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.

Treatment of Early Glottic cancer with Transoral Laser Microsurgery: An Australian Experience

Introduction

Early laryngeal carcinomas may be treated by transoral laser microsurgery (TLM) or external beam radiotherapy. We review our experience of surgical treatment of laryngeal pre-malignant and malignant lesions over the past 15 years in a high-volume head neck unit.

Methods

A review of a prospective patient database of patients with laryngeal SCC, who were treated with CO2 TLM between 2004 and 2019 was carried out.

Results

83 patients with a mean age of 67.7 (SD: 10.6) years underwent primary curative TLM for T1a/b SCC. 5-year overall survival was 93.2% (95%CI 86.9-100%), disease free survival was 86.0% (95%CI 78.1-94.6%), locoregional control was 91.2% (95%CI: 85.1-97.7%) and larynx preservation rate of 95.1% at 5 years.

Conclusion

TLM is an excellent treatment modality for T1 early glottic SCC, with excellent locoregional control and disease-free survival. It is minimally invasive, outpatient-based, and cost-effective procedure preserving upper aerodigestive tract dysfunction for all activities of daily living.

Dysplastic Lesions of the Larynx

There have been many advancements in the clinical and histologic diagnosis of laryngeal dysplasia (LD), but diagnosis still necessitates invasive histologic evaluation. Furthermore, despite improved histologic identification of dysplastic lesions, the exact details of pathophysiologic progression and the risk of malignant transformation is still uncertain. These unknowns create a barrier to establishing an ideal grading and classification system, which prevents the establishment of a precise and consistent treatment paradigm. Identifying these gaps in knowledge serves to highlight where further studies are warranted, ideally focusing on a better understanding of the biological behavior of LD. This would ultimately allow for the creation of a reliable grading and classification system and for the formalization of management and treatment guidelines for LD.

Arytenoid granuloma: a single-institution experience of management of 62 cases

OBJECTIVE

This retrospective study was undertaken to assess the outcome of the medical and/or surgical management of patients presenting with clinical features of arytenoid granuloma.

METHODS

The records of 53 males and 9 females were reviewed for predisposing factors, types of treatment received and recurrence following the treatment.

RESULTS

Most of the patients (48 out of 62, 77.4 per cent) were treated conservatively with medical management and voice therapy, which resulted in complete resolution of arytenoid granuloma in over two-thirds of the patients treated (32 out of 48, 66.6 per cent). Overall, 28 patients (out of 62, 45.1 per cent) required surgery (14 failed medical treatment cases and 14 surgery as first-line treatment cases). Of these, five patients (out of 28, 17.9 per cent) had recurrence, and were managed with revision surgery and concurrent local injection of Botox.

CONCLUSION

Anti-reflux medication and voice therapy are effective first-line management options. Pre- and post-surgery adjuvant treatment improves the results of surgery. Local injection of Botox was successful in the treatment of failed surgical cases.

A Case Report of Rare Vocal Cord Hemangioendothelioma in a Paediatric Larynx

Hemangioendothelioma (HEM) is a vascular tumour which is locally aggressive with a low-grade malignant potential. We present a rare case of HEM arising from the vocal cord of a 10-year-old female child. Video laryngoscopy clearly showed a large vocal cord polyp-like mass attached to middle one-third of left cord. Histopathological examination showed fragments of tissue with a neoplasm composed of spindle cells arranged diffusely admixed with numerous small vascular channels. These specific cells were positive for CD31, CD34, vimentin and ERG. Flexiblescopy and narrow band imaging were performed 3 weeks after surgery which showed no residual mass. Treatment of HEM is hampered by lack of proper guidelines and protocol. In this case of localized vocal cord lesion, a wide excision with regular follow up is considered ideal.

Narrative Review of Classification Systems Describing Laryngeal Vascularity Using Advanced Endoscopic Imaging

Endoscopic methods are critical in the early diagnosis of mucosal lesions of the head and neck. In recent years, new examination methods and classification systems have been developed and introduced into clinical practice. All of these new techniques target the notion of optical biopsy, which tries to assess the nature of the lesion before histology examination. Many methods suffer from interpretation issues due to subjective interpretation of the findings. Therefore, multiple classification systems have been developed to assist the proper interpretation of mucosal findings and reduce the error rate. They provide various perspectives on the assessment and interpretation of mucosa changes. This article provides a comprehensive and critical view of the available classification systems as well as their advantages and disadvantages.

LPCANet: Classification of Laryngeal Cancer Histopathological Images Using a CNN with Position Attention and Channel Attention Mechanisms

Laryngeal cancer is one of the most common malignant tumors in otolaryngology, and histopathological image analysis is the gold standard for the diagnosis of laryngeal cancer. However, pathologists have high subjectivity in their diagnoses, which makes it easy to miss diagnoses and misdiagnose. In addition, according to a literature search, there is currently no computer-aided diagnosis (CAD) algorithm that has been applied to the classification of histopathological images of laryngeal cancer. Convolutional neural networks (CNNs) are widely used in various other cancer classification tasks. However, the potential global and channel relationships of images may be ignored, which will affect the feature representation ability. Simultaneously, due to the lack of interpretability, the results are often difficult to accept by pathologists. we propose a laryngeal cancer classification network (LPCANet) based on a CNN and attention mechanisms. First, the original histopathological images are sequentially cropped into patches. Then, the patches are input into the basic ResNet50 to extract the local features. Then, a position attention module and a channel attention module are added in parallel to capture the spatial dependency and the channel dependency, respectively. The two modules produce the fusion feature map to enhance the feature representation and improve network classification performance. Moreover, the fusion feature map is extracted and visually analyzed by the grad-weighted class activation map (Grad_CAM) to provide a certain interpretability for the final results. The three-class classification performance of LPCANet is better than those of the five state-of-the-art classifiers (VGG16, ResNet50, InceptionV3, Xception and DenseNet121) on the two original resolutions (534 * 400 and 1067 * 800). On the 534 * 400 data, LPCANet achieved 73.18% accuracy, 74.04% precision, 73.15% recall, 72.9% F1-score, and 0.8826 AUC. On the 1067 * 800 data, LPCANet achieved 83.15% accuracy, 83.5% precision, 83.1% recall, 83.1% F1-score, and 0.9487 AUC. The results show that LPCANet enhances the feature representation by capturing the global and channel relationships and achieves better classification performance. In addition, the visual analysis of Grad_CAM makes the results interpretable, which makes it easier for the results to be accepted by pathologists and allows the method to become a second tool for auxiliary diagnosis.

Diagnostic Value of Narrow Band Imaging in Visualization of Pathological Lesions in Larynx and Hypopharynx

INTRODUCTION

Narrow Band Imaging (NBI) is an endoscopic optical imaging enhancement technology that improves the contrast of mucosal surface texture and enhances visualization of mucosal and submucosal vasculature. Due to its properties, it can visualize suspected malignant or precancerous lesions earlier than conventional white light endoscopy. The aim of this study was to analyze the benefit of NBI in visualization of precancerous and malignant lesions in preoperative and intraoperative diagnostics and correlation with histopathologic results.

METHODS

A total of 589 patients with suspicious laryngeal or hypopharyngeal lesion were investigated using conventional white light endoscopy (WLE) and NBI endoscopy with high-definition TV (HDTV NBI) from 10/2013 to 12/2019. Patients were divided into two groups based on pre-operative NBI examination (group A, 345 patients) and intraoperative NBI examination (group B, 244 patients). All suspicious lesions were graded to 5 types of Ni classification and correlated with histopathologic results. The SPSS version 8.0.4 statistical software package was used for statistical analysis. In diagnosing premalignant and malignant lesions sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

RESULTS

The agreement between NBI endoscopy and histopathological analysis in group A was statistically significant (Қ = 0.76, p < 0.001), with a sensitivity of 86.2% (95% IS: 65.4-95.2) and specificity of 90.9% (95% IS: 70.6-94.1). Moreover, in group B was proven almost perfect agreement between NBI and histopathological analysis (Қ = 0.8461, p < 0.001), with a sensitivity of 84.0% (95% IS: 60.2-92.4) and specificity of 96.0% (95% IS: 87.0-99.2).

CONCLUSIONS

Based on our results, NBI using the Ni classification has great potential in improving diagnosis of precancerous and malignant lesions and correlates strongly with histopathologic results. It serves as a useful adjunct to white light endoscopy in the diagnosis of laryngeal and hypopharyngeal lesions, especially using HDTV NBI.