Narrow band imaging for the diagnosis of head and neck squamous cell carcinoma: A systematic review

Assessment of Narrow-Band Imaging Algorithm for Video Capsule Endoscopy Based on Decorrelated Color Space for Esophageal Cancer: Part II, Detection and Classification of Esophageal Cancer

Esophageal carcinoma (EC) is a prominent contributor to cancer-related mortality since it lacks discernible features in its first phases. Multiple studies have shown that narrow-band imaging (NBI) has superior accuracy, sensitivity, and specificity in detecting EC compared to white light imaging (WLI). Thus, this study innovatively employs a color space linked to décor to transform WLIs into NBIs, offering a novel approach to enhance the detection capabilities of EC in its early stages. In this study a total of 3415 WLI along with the corresponding 3415 simulated NBI images were used for analysis combined with the YOLOv5 algorithm to train the WLI images and the NBI images individually showcasing the adaptability of advanced object detection techniques in the context of medical image analysis. The evaluation of the model's performance was based on the produced confusion matrix and five key metrics: precision, recall, specificity, accuracy, and F1-score of the trained model. The model underwent training to accurately identify three specific manifestations of EC, namely dysplasia, squamous cell carcinoma (SCC), and polyps demonstrates a nuanced and targeted analysis, addressing diverse aspects of EC pathology for a more comprehensive understanding. The NBI model effectively enhanced both its recall and accuracy rates in detecting dysplasia cancer, a pre-cancerous stage that might improve the overall five-year survival rate. Conversely, the SCC category decreased its accuracy and recall rate, although the NBI and WLI models performed similarly in recognizing the polyp. The NBI model demonstrated an accuracy of 0.60, 0.81, and 0.66 in the dysplasia, SCC, and polyp categories, respectively. Additionally, it attained a recall rate of 0.40, 0.73, and 0.76 in the same categories. The WLI model demonstrated an accuracy of 0.56, 0.99, and 0.65 in the dysplasia, SCC, and polyp categories, respectively. Additionally, it obtained a recall rate of 0.39, 0.86, and 0.78 in the same categories, respectively. The limited number of training photos is the reason for the suboptimal performance of the NBI model which can be improved by increasing the dataset.

Diagnostic Performance of a Novel Ultra-Thin Endoscopy under Narrow-Band Imaging for Superficial Squamous Cell Carcinoma of the Pharynx and Esophagus

This study aimed to evaluate the diagnostic utility of the ultra-thin endoscope (UTE) for superficial squamous cell carcinoma (SSCC) compared to magnifying endoscopy (ME) under narrow-band imaging. Participants underwent endoscopic examination, and images of pharyngeal and esophageal SCCs, as along with suspicious SSCC lesions, were collected using UTE and ME on the same day. Three image catalogs (UTE, ME-1, and ME-2) were created and reviewed by three expert endoscopists. ME-1 and ME-2 contained the same endoscopic images. The primary endpoint was the intra-observer agreement for diagnosing SCC. Eighty-six lesions (SCC = thirty-nine, non-SCC = forty-seven) in 43 participants were identified. The kappa values for the intra-observer agreement between UTE and ME-1 vs. the control (ME-1 vs. ME-2) were 0.74 vs. 0.84, 0.63 vs. 0.76, and 0.79 vs. 0.88, respectively. The accuracies for diagnosing SCC by UTE and ME-1 were 87.2% vs. 86.0%, 78.0% vs. 73,2%, and 75.6 vs. 82.6%, respectively, with no significant differences (p > 0.05). The rates of lesions that were diagnosed with confidence by UTE and ME-1 were 30.2% vs. 27.9%, 55.8% vs. 62.8%, and 58.1% vs. 55.8%, respectively. UTE demonstrates substantial diagnostic performance for SSCC in the pharynx and esophagus.

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.

Vocal fold leukoplakia recurrence risk model

The paper aims to define the variables that elevate the risk of VFL recurrence after adequate primary treatment, and to present the Recurrence Risk Model with practical conclusions to handle pVFL and rVFL. Out of 207 patients with primary vocal fold leukoplakia (pVFL), in 41 (19.8%) recurrent VFL (rVFL) was diagnosed. All patients were assessed by using a trans-nasal flexible video-endoscope using white light, and NBI. The primary measure of our study was to investigate whether morphological features of pVFL in WL, vascular pattern in NBI, and primary histological findings could predict VFL recurrence. To create a model of risk factors, two methods were used: logistic regression and a conditional inference decision tree. The study showed smoking was the factor that significantly and most strongly increased the likelihood of rVFL, as well as the older age groups have a greater odds of rVFL. Types IV, V and VI, according to Ni 2019 classification, were associated with a significantly higher risk of rVFL. The algorithm combining patients' dependent variables and the combination of two classifications improves the predictive value of the presented VFL Recurrence Risk Model.

Cost-Effectiveness Analysis of PET-CT Surveillance After Treatment of Human Papillomavirus-Positive Oropharyngeal Cancer

OBJECTIVE

To determine the cost-effectiveness of surveillance imaging with PET/CT scan among patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma.

STUDY DESIGN

Cost-effectiveness analysis.

SETTING

Oncologic care centers in the United States with head and neck oncologic surgeons and physicians.

METHODS

We compared the cost-effectiveness of 2 posttreatment surveillance strategies: clinical surveillance with the addition of PET/CT scan versus clinical surveillance alone in human papillomavirus-positive oropharyngeal squamous cell carcinoma patients. We constructed a Markov decision model which was analyzed from a third-party payer's perspective using 1-year Markov cycles and a 30-year time horizon. Values for transition probabilities, costs, health care utilities, and their studied ranges were derived from the literature.

RESULTS

The incremental cost-effectiveness ratio for PET/CT with clinical surveillance versus clinical surveillance alone was $89,850 per quality-adjusted life year gained. Flexible fiberoptic scope exams during clinical surveillance would have to be over 51% sensitive or PET/CT scan cost would have to exceed $1678 for clinical surveillance alone to be more cost-effective. The willingness-to-pay threshold at which imaging surveillance was equally cost-effective to clinical surveillance was approximately $80,000/QALY.

CONCLUSION

Despite lower recurrence rates of human papillomavirus-positive oropharyngeal cancer, a single PET/CT scan within 6 months after primary treatment remains a cost-effective tool for routine surveillance when its cost does not exceed $1678. The cost-effectiveness of this strategy is also dependent on the clinical surveillance sensitivity (flexible fiberoptic pharyngoscopy), and willingness-to-pay thresholds which vary by country.

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer: A Randomized Controlled Trial

OBJECTIVE

Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes.

STUDY DESIGN

Randomized controlled trial, performed between September 2015 and November 2022.

SETTING

A tertiary referral hospital in The Netherlands.

METHODS

TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed.

RESULTS

Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p = .002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p = .07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p = .09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p = .02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p = .02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p = .08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p = .16).

CONCLUSION

The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.

Electric Bioimpedance Sensing for the Detection of Head and Neck Squamous Cell Carcinoma

The early detection of head and neck squamous cell carcinoma (HNSCC) is essential to improve patient prognosis and enable organ and function preservation treatments. The objective of this study is to assess the feasibility of using electrical bioimpedance (EBI) sensing technology to detect HNSCC tissue. A prospective study was carried out analyzing tissue from 46 patients undergoing surgery for HNSCC. The goal was the correct identification of pathologic tissue using a novel needle-based EBI sensing device and AI-based classifiers. Considering the data from the overall patient cohort, the system achieved accuracies between 0.67 and 0.93 when tested on tissues from the mucosa, skin, muscle, lymph node, and cartilage. Furthermore, when considering a patient-specific setting, the accuracy range increased to values between 0.82 and 0.95. This indicates that more reliable results may be achieved when considering a tissue-specific and patient-specific tissue assessment approach. Overall, this study shows that EBI sensing may be a reliable technology to distinguish pathologic from healthy tissue in the head and neck region. This observation supports the continuation of this research on the clinical use of EBI-based devices for early detection and margin assessment of HNSCC.

Cervical squamous cell carcinoma of unknown primary: Oncological outcomes and prognostic factors

Background/Objectives

Cervical squamous cell carcinoma of unknown primary (SCCUP) is a rare entity within head and neck cancer and both treatment regimens as well as identified potential predictors for oncological outcomes vary between published series. In this study, we evaluated oncological outcomes and identified potential prognostic factors for outcome.

Patients and methods

This retrospective monocentric cohort study includes 82 SCCUP patients diagnosed and treated between January 2000 and June 2021. Overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS) and locoregional recurrence-free survival (LRFS) were evaluated. The Cox proportional hazards model was used to analyze the prognostic effect of patient and tumor characteristics on oncological outcomes.

Results

Five year OS, DSS, DFS and LRFS were respectively 53.9%, 72.2%, 68.9% and 67.3%. The p16 status was evaluated in 55 patients with 40% being p16 positive. On univariable analysis, p16 negative SCCUPs had significantly worse survival and recurrence rates in the presence of clinical extranodal extension (cENE) (OS: p=0.0013, DSS: p=0.0099, DFS: p=0.0164, LRFS: p=0.0099) and radiological extranodal extension (rENE) (OS: p=0.0034, DSS: p=0.0137, DFS: p=0.0167, LRFS: p=0.0100). In p16 positive SCCUP patients, rENE had a significantly negative prognostic effect on DFS (p=0.0345) and LRFS (p=0.0367). Total group multivariate analysis identified rENE as an independent negative predictor for all oncological outcomes. The “number of positive lymph nodes” was a second independent predictor for DSS (p=0.0257) and DFS (p=0.0435).

Conclusions

We report favorable oncological outcomes, comparable to previously published results. Although the presence of rENE seems associated with poor oncological outcomes, the differential effect of clinical, radiological and pathological ENE in both p16 positive and negative subgroups remain to be elucidated by further prospective research.

NBI and Laryngeal Papillomatosis: A Diagnostic Challenge: A Systematic Review

Highlights

Abstract

Narrow-band imaging (NBI) represents a valid aid in laryngeal squamous cell carcinoma (LSCC) diagnosis for detecting vascular changes. However, LSCC and laryngeal papillomatosis (LP) show similar vascular patterns that may lead to misdiagnosis and improper treatment. This review aims to deepen this NBI limit in order to stress a careful preoperative evaluation of laryngeal lesions. The research was carried out on PubMed, Web of Science and Scopus databases using specific keywords. The topic of research was assessed by these parameters: accuracy, sensitivity, specificity, and positive and negative predictive values. This review included only five articles: they demonstrated that NBI is better than white-light endoscopy in detecting LSCC and LP. They also reported that LP is frequently mistaken for LSCC, resulting in high rates of false positives using NBI. This is the first review that emphasized this NBI limitation in distinguishing between LP and LSCC in cases of a type V pattern of intraepithelial papillary capillary loop. Although NBI application increased the rate of early cancer detection, LP reduces NBI accuracy. This drawback may lead to misdiagnosis and improper treatment. Our advice is to be careful in cases of type V pattern on NBI and to research LP epithelial and clinical features because it could be a pitfall.

Diagnostic Accuracy of High-Grade Intraepithelial Papillary Capillary Loops by Narrow Band Imaging for Early Detection of Oral Malignancy: A Cross-Sectional Clinicopathological Imaging Study

Simple Summary

This study aimed to clarify the advantages and disadvantages of conventional visual inspection (CVI), endoscopic white light imaging (WLI), and narrow-band imaging (NBI) and to examine the diagnostic accuracy of intraepithelial papillary capillary loops (IPCL) for the detection of oral squamous cell carcinoma (OSCC). All OSCC cases showed high-grade (Type III–IV) IPCL. A non-homogeneous lesion with high-grade IPCL strongly suggested malignancy. Our results indicate that WLI and NBI are powerful tools for detecting precancerous and cancerous lesions using IPCL. However, NBI is influenced by mucosal thickness; therefore, image interpretation is important.

Abstract

This study aimed to clarify the advantages and disadvantages of conventional visual inspection (CVI), endoscopic white light imaging (WLI), and narrow-band imaging (NBI) and to examine the diagnostic accuracy of intraepithelial papillary capillary loops (IPCL) for the detection of oral squamous cell carcinoma (OSCC). This cross-sectional study included 60 participants with oral mucosal diseases suspected of having oral potentially malignant disorders (OPMDs) or OSCC. The patients underwent CVI, WLI, NBI, and incisional biopsy. Images were evaluated to assess the lesion size, color, texture, and IPCL. Oral lichen planus (OLP) and oral leukoplakia lesions were observed in larger areas with NBI than with WLI; 75.0% were associated with low-grade (Type 0–II) IPCL. Various types of oral leukoplakia were seen; however, all OSCC cases showed high-grade (Type III–IV) IPCL. The diagnostic accuracy of high-grade IPCL for OSCC showed a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 100%, 80.9%, 59.1%, 100%, and 85.0%, respectively. A non-homogeneous lesion with high-grade IPCL strongly suggested malignancy. Overall, our results indicate that WLI and NBI are powerful tools for detecting precancerous and cancerous lesions using IPCL. However, NBI is influenced by mucosal thickness; therefore, image interpretation is important for accurate diagnosis.

An overview of the current clinical status of optical imaging in head and neck cancer with a focus on Narrow Band imaging and fluorescence optical imaging

Early and accurate identification of head and neck squamous cell carcinoma (HNSCC) is important to improve treatment outcomes and prognosis. New optical imaging techniques may assist in both the diagnostic process as well as in the operative setting by real-time visualization and delineation of tumor. Narrow Band Imaging (NBI) is an endoscopic technique that uses blue and green light to enhance mucosal and submucosal blood vessels, leading to better detection of (pre)malignant lesions showing aberrant blood vessel patterns. Fluorescence optical imaging makes use of near-infrared fluorescent agents to visualize and delineate HNSCC, resulting in fewer positive surgical margins. Targeted fluorescent agents, such as fluorophores conjugated to antibodies, show the most promising results. The aim of this review is: (1) to provide the clinical head and neck surgeon an overview of the current clinical status of various optical imaging techniques in head and neck cancer; (2) to provide an in-depth review of NBI and fluorescence optical imaging, as these techniques have the highest potential for clinical implementation; and (3) to describe future improvements and developments within the field of these two techniques.

Endoscopic diagnosis value of narrow band imaging Ni classification in vocal fold leukoplakia and early glottic cancer

OBJECTIVES

To explore the diagnostic value and the correlation between histological diagnosis and the Ni classification under narrow band imaging (NBI) for vocal fold leukoplakia (VFL) and early glottic cancer.

METHODS

A total of 91 patients with 119 vocal fold lesions were selected from January 2017 to May 2020. All these patients were subsequently examined by white light imaging (WLI) and NBI endoscopy, and then all lesions were classified by the Ni classification according to the characteristics of intraepithelial papillary capillary loop (IPCL) observed. The gold standard of diagnosis was histopathological results. Eventually, the chi-square and kappa test were applied, respectively, to evaluate the diagnostic value of NBI endoscopy and the consistency of Ni classification and pathological results.

RESULTS

The accuracy and sensitivity of NBI endoscopy were significantly higher than that of WLI endoscopy (P < 0.05). For the diagnosis of precancerous lesions under the NBI, the sensitivity, specificity, positive and negative predictive value were 69.6% (16/23), 90.6% (87/96), 64.0% (16/25) and 92.6% (87/94), which for malignant lesions were 84.4% (65/77), 92.9% (39/42), 95.6% (65/68) and 76.5% (39/51). Moreover, for patients with low-grade intraepithelial neoplasia (mild and moderate dysplasia), type IV lesions accounted for the most (69.6 vs 30.4%; χ² = 36.961, P < 0.001). For high-grade intraepithelial neoplasia or carcinoma in situ, type Va lesions were predominant (χ² = 30.526, P < 0.001), while type Vb and Vc lesions were dominant in invasive carcinoma (χ² = 64.373, P < 0.001). Besides, the kappa test revealed that there was a high consistency between Ni classification and pathological diagnosis (Kappa = 0.667, P < 0.001).

CONCLUSIONS

The Ni classification can improve the diagnosis accuracy of vocal fold lesions which enables clear visualization of mucosal microvasculature. This is essential for the early diagnosis of VFL and early glottic cancer during routine endoscopic examination.

Diagnostic approaches to carcinoma of unknown primary of the head and neck

Squamous cell carcinoma in cervical lymph nodes arising from an undetected primary tumour, termed carcinoma of unknown primary (SCCUP), is a well-recognized clinical presentation within head and neck oncology. SCCUP is a common presentation for patients with human papillomavirus-mediated oropharyngeal cancer (HPV + OPSCC), as patients with HPV + OPSCC often present with smaller primary tumours and early nodal metastasis. Meticulous work-up of the SCCUP patient is central to the management of these patients as identification of the primary site improves overall survival and allows for definitive oncologic resection or more focused radiation when indicated. This review summarizes the comprehensive diagnostic approach to the SCCUP patient, including history and physical examination, methods of biopsy of the cervical lymph node, imaging modalities and intraoperative methods to localize the unknown primary. Novel techniques such as transcervical ultrasound of the oropharynx, narrow band imaging and diagnostic transoral robotic surgery are also discussed.

Narrow band imaging observed oral mucosa microvasculature as a tool to detect early oral cancer: an Indian experience

BACKGROUND

Narrow band imaging (NBI) is a novel method with the potential to improve the diagnostic capability of white-light.

METHODS

A prospective observational study of 50 consecutive patients, with suspicious malignant/premalignant lesions. White-light images were assessed as suspicious for malignancy/negative for malignancy, whereas NBI images were classified based on the IPCL patterns. All lesions underwent biopsy and accuracy was compared with the histopathology (Fig. 1). Fig. 1 Representative images of the IPCL patterns from Types I-IV RESULTS: 25 lesions (49%) were positive for malignancy, 2 (3.9%) lesions showed severe dysplasia, and 24(47%) were considered negative on histopathology. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of white light and NBI in detecting invasive carcinoma was 74.07%, 79.17%, 80.00%, 73.08% and 76.47%, and 92.67%, 90.16%, 92.56%, 91.67% and 92.16% respectively. The NBI group had a significantly better sensitivity and specificity to white light. The interobserver concordance was κ = 0.881.

CONCLUSION

NBI is a highly effective tool to detect invasive carcinomas amongst suspicious lesions of the oral cavity.

Contribution of narrow band imaging in delineation of laryngopharyngeal superficial cancer spread: a prospective study

PURPOSE

The aim of this study was to assess the performance of Narrow Band Imaging (NBI) added to White Light (WL) in the delineation of laryngopharyngeal superficial cancer spread during office-based transnasal flexible endoscopy.

METHODS

This bi-centric prospective study was conducted between October 2014 and December 2017. We included consecutive patients with laryngopharyngeal malignant tumors. Transnasal flexible endoscopy was performed by two endoscopists who were blinded to each other's assessments and who examined each patient independently. The first endoscopist only performed a WL examination, while the second endoscopist carried out both WL and NBI. The extent of tumor involvement was reported based on predefined anatomical sub-units. Biopsies in NBI + /WL- sub-units were subsequently performed during panendoscopy.

RESULTS

Eighty-four patients were included in the study. A total of 72 NBI + /WL- sub-units were sampled in 38 patients, and 37 of the biopsies were positive (51.4%): 16 for invasive carcinoma, 17 for high-grade dysplasia/carcinoma in situ and 4 for low-grade dysplasia. Ultimately, 26.2% of patients had at least one positive biopsy in an NBI + /WL- sub-unit and, therefore, a better tumor delineation. The clinical T stage was upgraded in 4.8% of cases examined.

CONCLUSION

Adding NBI to WL imaging during transnasal flexible endoscopy in patients presenting with laryngopharyngeal pre-malignant or malignant lesions improves the delineation of superficial cancer spread, thereby leading to better adapted treatments. Clinicaltrials.gov registration number: NCT02035735.

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.

NBI utility in oncologic surgery: An organ by organ review

The main aims of the oncologic surgeon should be an early tumor diagnosis, complete surgical resection, and a careful post-treatment follow-up to ensure a prompt diagnosis of recurrence. Radiologic and endoscopic methods have been traditionally used for these purposes, but their accuracy might sometimes be suboptimal. Technological improvements could help the clinician during the diagnostic and therapeutic management of tumors. Narrow band imaging (NBI) belongs to optical image techniques, and uses light characteristics to enhance tissue vascularization. Because neoangiogenesis is a fundamental step during carcinogenesis, NBI could be useful in the diagnostic and therapeutic workup of tumors. Since its introduction in 2001, NBI use has rapidly spread in different oncologic specialties with clear advantages. There is an active interest in this topic as demonstrated by the thriving literature. It is unavoidable for clinicians to gain in-depth knowledge about the application of NBI to their specific field, losing the overall view on the topic. However, by looking at other fields of application, clinicians could find ideas to improve NBI use in their own specialty. The aim of this review is to summarize the existing literature on NBI use in oncology, with the aim of providing the state of the art: we present an overview on NBI fields of application, results, and possible future improvements in the different specialties.

Role of Narrow Band Imaging Endoscopy in Preoperative Evaluation of Laryngeal Leukoplakia: A Review of the Literature

INTRODUCTION

Leukoplakia is a precancerous lesion considered to be within the spectrum of histopathological results from parakeratosis, through stages of dysplasia to invasive cancer. Narrow band imaging (NBI) endoscopy has been introduced to improve early diagnosis of benign and malignant laryngeal lesions. The aim of this literature review was to evaluate the accuracy of preoperative evaluation of vocal fold leukoplakia with NBI endoscopy in comparison with histology.

METHODS

A systematic review of the literature was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using 3 different databases: PubMed, Embase, and Scopus. The included articles in the systematic review were identified combining each of the following terms: "narrow band imaging" OR "NBI," [AND] with each of these terms: "laryngeal leukoplakia," OR "vocal fold leukoplakia," OR "vocal cord leukoplakia."

RESULTS

The articles that fully met the inclusion criteria were 5 case series, conducted between January 2010 and February 2018, and published between 2017 and 2019. The selected articles included 312 patients (86% males and 14% females), affected by 382 vocal cord leukoplakia, evaluated with NBI endoscopy and that underwent surgical microlaryngoscopy with biopsy. Based on the studies included in the review, accuracy of NBI in predicting malignancy within leukoplakia ranged from 81% to 97.8%, demonstrating to be an accurate method to predict the risk of malignant transformation of vocal fold leukoplakia.

CONCLUSION

Narrow band imaging can help otolaryngologists in the decision-making process on the necessity to perform a biopsy and transoral surgery or long-term follow-up. Larger studies are necessary to confirm the high association of NBI evaluation of the epithelium surrounding the leukoplakia with the histological diagnosis.

Metastatic Squamous Cell Carcinoma to the Cervical Lymph Nodes From an Unknown Primary Cancer: Management in the HPV Era

Background

Patients with metastases in the lymph nodes of the neck and no obvious primary tumor, neck cancer with unknown primary (NCUP), represent a management challenge. A majority of patients have metastatic squamous cell carcinoma (SCC), although other histologies do occur.

Methods

We comprehensively reviewed the literature, compared available guidelines, and conferred with an international team of experts.

Results

Positron emission tomography-computed tomography (PET-CT) and fine needle aspiration (FNA) under ultrasound guidance increase accuracy of diagnosis. Immunohistochemistry (IHC), determination of human papilloma virus (HPV) status, by p16 staining or by in situ hybridization (ISH), and next-generation gene sequencing can guide us regarding probable primary sites and tumor biology. Narrow Band Imaging (NBI) has been introduced for the early detection of subtle mucosal lesions. Direct laryngoscopy (DL) and tonsillectomy have long been procedures used in the search for a primary site. More recently, TransOral Robotic Surgery (TORS) or Transoral LASER Microsurgery (TLM) have been introduced for lingual tonsillectomy.

Conclusions

New technologies have been developed which can better detect, diagnose, and treat occult primary tumors. Decisions regarding therapy are based on the primary tumor site (if discovered) and N stage. Options include neck dissection with or without postoperative adjuvant therapy, primary irradiation, or combined chemotherapy with irradiation. The preferred treatment of patients whose primary remains unidentified is controversial.

Effect of a training course on the diagnosis of vocal fold leukoplakia by narrow-band imaging

OBJECTIVE

To investigate the value of narrow-band imaging training for differentiating between benign and malignant vocal fold leukoplakia.

METHOD

Thirty cases of vocal fold leukoplakia were selected.

RESULTS

Narrow-band imaging endoscopy training had a significant positive effect on the specificity of the differential diagnosis of vocal fold leukoplakia. In addition, the consistency of diagnostic typing of vocal fold leukoplakia by narrow-band imaging improved to 'moderate agreement' following the combination of types I and II and the combination of types IV, V and VI in the typing of vocal fold leukoplakia.

CONCLUSION

The narrow-band imaging training course may improve the ability of laryngologists to diagnose vocal fold leukoplakia. The new endoscopic diagnostic classification by narrow-band imaging needs to be further simplified to facilitate clinical application.

Role of Transoral Robotic Surgery in the Work-up of the Unknown Primary

Unknown primary squamous cell carcinoma metastatic to cervical lymph nodes is a relatively rare tumor presentation, although the incidence may be increasing along with the rising incidence of human papilloma virus-mediated oropharyngeal cancers. Traditional diagnostic methods with palatine tonsillectomy and panendoscopy may identify the minority of primary tumors. The addition of a transoral lingual tonsillectomy may improve the diagnostic yield of identifying a primary tumor. Incorporation of transoral robotic surgery may be used for diagnostic purposes to identify a primary site and also for therapeutic purposes, whereby a primary tumor may be completely resected and combined with a neck dissection.

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

INTRODUCTION

Narrowband imaging (NBI) is a special endoscopic optical enhancement setting allowing better visualization of mucosal microvasculature compared to white light endoscopy. This study evaluates the validity of NBI using the Ni classification in the detection and differentiation of severe dysplasia (SD) and glottic squamous cell carcinoma (SCC).

METHODS

Patients with suspicious vocal cord lesions underwent conventional white light endoscopy followed by clinically indicated biopsy. At the same time, NBI images were obtained and graded independently. Lesions were graded from I to V according to the Ni classification and compared to histopathological findings.

RESULTS

Fifty-two patients were included in this study (40 SCC and 12 SD). The sensitivity and specificity of NBI in diagnosing laryngeal cancer was 95.0% (CI, 83.9%-99.4%) and 83.3% (CI, 51.6%-97.9%), respectively. The negative likelihood ratio was 0.06. Higher Ni grades correlated very strongly with more advanced disease.

CONCLUSIONS

NBI using the Ni classification is a sensitive diagnostic tool for the detection and differentiation of early neoplastic and preneoplastic glottic lesions. As higher Ni classification correlates strongly with advanced disease, it serves as a useful adjunct to white light endoscopy in the diagnosis of laryngeal cancer.Level of Evidence: Level IV.

Clinical experience of narrow band imaging (NBI) usage in diagnosis of laryngeal lesions

INTRODUCTION

One of the most recent methods used in imaging of the larynx is narrow band imaging (NBI). NBI enables us to detect specific patterns of pathological angiogenesis suggestive of premalignant or neoplastic lesions. The aim of the study was to compare imaging of laryngeal lesions in white light endoscopy (WLE) and NBI in relation to histopathological examination.

MATERIAL AND METHODS

333 patients with laryngeal lesions underwent endoscopic evaluation in WLE and NBI. Sensitivity, specificity, positive and negative predictive value (PPV, NPV) for WLE and NBI were calculated. The diagnostic value for WLE and NBI was evaluated for two assumptions (positive result is:1. severe dysplasia and cancer 2. only cancer) Results: Sensitivity, specificity, PPV, NPV of first assumption were respectively for white light compared to NBI: 95.4% vs 98.5%; 84.2% vs 98.5%; 79.6% vs 97.7% and 96.6% vs 99.0%. The values of second assumption were: 97.4% vs 100%; 79.3% vs 93.5%; 72.6% vs. 89.4% and 98.2% vs. 100.0%. Higher sensitivity was observed for the second assumption, while higher specifity was recorded for the first assumption. Specificity was significantly higher for NBI than for WLE (p&lt;0.001).

CONCLUSIONS

NBI enables us to detect and differentiate laryngeal lesions, which are invisible in WLE. Endoscopic examination, especially in NBI-mode, is non-invasive, repeatable and remains a useful tool in the daily practice and diagnosis of patients with pathological lesions in the larynx.

A systematic review on Transoral robotic surgery (TORS) for carcinoma of unknown primary origin: Has tongue base mucosectomy become indispensable?

Background

Transoral robotic surgery (TORS) is increasingly used in head and neck surgery and in carcinoma of unknown primary (CUP) origin specifically. Due to the rising incidence of human papillomavirus (HPV)‐related oropharyngeal squamous cell carcinoma (OPSCC), there is a rationale for finding ways to de‐escalate treatment strategies. This review aims to test the hypothesis that TORS is a meaningful adjunct in the diagnostic (and therapeutic) pathway in CUP in head and neck.

Methods

A structured search of the literature was performed with the search terms ‘TORS’ and ‘Carcinoma of Unknown Primary’.

Results

Two hundred and seventy four cases of CUP in which TORS was used were identified for further analysis. Workup for CUP was comparable in all series with regard to physical examination, fine and/or gross needle examination of cervical nodes, fibre optic endoscopy, imaging and robot assisted mucosectomy of the base of tongue (BOT). Identification rate of the primary tumour was 72% on average (range 17%‐ 90%), and 55%‐ 96% were HPV positive. Clear margins were achieved in 60% (range 0%‐85%) of resected occult tumours. Complication rate of TORS BOT mucosectomy was low with mainly grade I‐III sequelae according to Clavien–Dindo.

Conclusions

Transoral robotic surgery seems to be a useful and safe adjunct in the diagnostic and therapeutic pathway in case of CUP in an era of increasing incidence of HPV‐positive OPSCC.

Diagnostic Value and Pathological Correlation of Narrow Band Imaging Classification in Laryngeal Lesions

OBJECTIVES

To explore the diagnostic value and pathological correlation of narrow band imaging (NBI) classification in laryngeal lesions.

METHODS

A total of 112 patients (123 lesions) with laryngeal lesions from July 2018 to May 2019 were selected in this study. All patients were examined by NBI and white light imaging endoscopy. The NBI endoscopy was applied to classify the observed lesion sites according to intraepithelial papillary capillary loop pattern. The gold standard of diagnosis was pathological results. To evaluate the consistency of NBI classification and pathological results.

RESULTS

The sensitivity, specificity, positive predictive value, and negative predictive value of the diagnosis for benign, precancerous, and malignant lesions under the NBI endoscopy were 90.91%, 81.19%, 74.07%, 85.42%; 41.67%, 92.93%, 58.82%, 86.79%; and 93.51%, 65.22%, 91.14%, 68.18%, respectively. There was a high consistency between NBI classification and pathological results (κ = 0.679, P < .001).

CONCLUSIONS

The NBI classification can improve the accuracy of the diagnosis of laryngeal lesions. It is important for early diagnosis and treatment of vocal cord leukoplakia and laryngeal cancer.

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.

Diagnosis and Management of Squamous Cell Carcinoma of Unknown Primary in the Head and Neck: ASCO Guideline

PURPOSE

To provide evidence-based recommendations to practicing physicians and other health care providers on the diagnosis and management of squamous cell carcinoma of unknown primary in the head and neck (SCCUP).

METHODS

The American Society of Clinical Oncology convened an Expert Panel of medical oncology, surgery, radiation oncology, radiology, pathology, and advocacy experts to conduct a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 2008 through 2019. Outcomes of interest included survival, local and regional disease control, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 100 relevant studies to inform the evidence base for this guideline. Four main clinical questions were addressed, which included subquestions on preoperative evaluations, surgical diagnostic and therapeutic procedures, appropriate pathology techniques, and adjuvant therapy.

RECOMMENDATIONS

Evidence-based recommendations were developed to address preoperative evaluation for patients with a neck mass, surgical diagnostic and therapeutic procedures, appropriate treatment options in unilateral versus bilateral SCCUP.Additional information is available at www.asco.org/head-neck-cancer-guidelines.

A Mouse Model of Oropharyngeal Papillomavirus-Induced Neoplasia Using Novel Tools for Infection and Nasal Anesthesia

Human head and neck cancers that develop from the squamous cells of the oropharynx (Oropharyngeal Squamous Cell Carcinomas or OPSCC) are commonly associated with the papillomavirus infection. A papillomavirus infection-based mouse model of oropharyngeal tumorigenesis would be valuable for studying the development and treatment of these tumors. We have developed an efficient system using the mouse papillomavirus (MmuPV1) to generate dysplastic oropharyngeal lesions, including tumors, in the soft palate and the base of the tongue of two immune-deficient strains of mice. To maximize efficiency and safety during infection and endoscopy, we have designed a nose cone for isoflurane-induced anesthesia that takes advantage of a mouse’s need to breathe nasally and has a large window for oral manipulations. To reach and infect the oropharynx efficiently, we have repurposed the Greer Pick allergy testing device as a virus delivery tool. We show that the Pick can be used to infect the epithelium of the soft palate and the base of the tongue of mice directly, without prior scarification. The ability to induce and track oropharyngeal papillomavirus-induced tumors in the mouse, easily and robustly, will facilitate the study of oropharyngeal tumorigenesis and potential treatments.

Narrow band imaging in head and neck unknown primary carcinoma: A systematic review and meta-analysis

OBJECTIVE

To estimate the diagnostic performance of Narrow Band Imaging (NBI) in patients with cervical metastasis from head and neck squamous cell carcinoma of unknown primary (SCCUP) origin.

METHODS

PubMed, Embase, and Scopus databases were systematically scrutinized up to July 1, 2019, looking for studies that encompassed the NBI in the SCCUP diagnostic work up. The main inclusion criteria for eligible articles for the meta-analysis were non-evidence of primary tumor after physical examination and conventional cross-section imaging before NBI assessment and the availability of complete data on the diagnostic accuracy of NBI. A set of random-effects model meta-analyses was then performed following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines.

RESULTS

Five studies, conducted between January 2003 and September 2016, comprising 169 patients imaged with NBI, were included in the meta-analysis. The pooled sensitivity and specificity of NBI in patients with head and neck SCCUP was 0.83 (99% CI, 0.54-0.95) and 0.88 (99% CI, 0.55-0.97), respectively. The positive and negative likelihood ratios were 6.38 (99% CI, 1.6-25.44) and 0.06 (99% CI, 0.005-0.86). The pooled diagnostic odds ratio (DOR) was 82.15 (99% CI, 7.06-955). The overall detection rate of NBI was 0.35 (99% CI, 0.18-0.53), which allowed localization the primary tumor in 61 out of 169 patients, otherwise not detected by the usual diagnostic work-up.

CONCLUSIONS

Current available evidence suggests that NBI has a considerable diagnostic accuracy in patients affected by head and neck SCCUP. Laryngoscope, 130:1692-1700, 2020.

Role of narrow band imaging in the diagnosis of laryngeal lesions: Pilot study from India

INTRODUCTION

Narrow band imaging (NBI) is a new imaging technique developed to improve the diagnostic accuracy of head and neck cancers by depiction of tumor-specific neo-angiogenesis. The purpose of this study was to assess the value of NBI in the diagnosis of laryngeal lesions.

AIM

To assess the sensitivity and specificity of combined white light endoscopy (WLE) and NBI compared with WLE alone in the diagnosis of laryngeal lesions.

SETTINGS AND DESIGN

Prospective study.

MATERIALS AND METHODS

Thirty consecutive patients with various laryngeal lesions scheduled for microlaryngoscopic evaluation underwent WLE followed by NBI. Endoscopic NBI findings were classified into five types (I-V) according to the intraepithelial papillary capillary loop features. Types I-IV are considered benign, whereas type V is considered malignant. The observations were compared with histopathology.

STATISTICAL ANALYSIS

Sensitivity, specificity, and positive and negative predictive values for the diagnosis of malignancy (i.e., invasive carcinoma and carcinoma in situ) by means of NBI with WLE were calculated.

RESULTS

The sensitivity of WLE combined with NBI (100%) was higher than WLE alone (82.6%) in detecting laryngeal cancers. NBI helped in identifying four malignant lesions missed by WLE alone. Two children with respiratory papillomatosis also demonstrated type V pattern, a potential pitfall, leading to an overall positive predictive value of 92% and a negative predictive value of 100%.

CONCLUSION

Combining NBI with WLE increases the sensitivity of detection of laryngeal cancer and its precursor lesions. NBI is also useful in some benign lesions as well as in post-radiotherapy patients.

Unlocking the Potential of Saliva-Based Test to Detect HPV-16-Driven Oropharyngeal Cancer

The incidence of human papillomavirus (HPV)-positive oropharyngeal cancer (OPC) is rising in high-income countries, including Australia. Increasing evidence suggests that accurate HPV testing is pivotal for clinical decision making and treatment planning in these patients. Recently, the eighth edition of the American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) tumor-node-metastasis (TNM) staging system for OPC (based on the p16INK4a (p16) status) was proposed and has been implemented. However, the applicability of this new staging system is still far from clear. In our study, n = 127 OPC patients from Queensland, Australia were recruited, and the tumor p16 expression in these patients was examined using immunohistochemical (IHC) analysis. HPV-16 genotyping, viral load, and physical status (episomal versus integrated) in the saliva samples of OPC patients were determined using the qPCR method. A good inter-rater agreement (k = 0.612) was found between tumor p16 expression and oral HPV-16 infection in OPC. Importantly, according to the eighth edition staging system, HPV-16 DNA viral load (>10 copies/50 ng) was significantly associated with the advanced stages of OPC. In concordance with previous studies, a mixed HPV-16 form (partially or fully integrated) was predominately found in OPC patients. Taken together, our data support HPV-16 detection in saliva as a screening biomarker to identify people within the community who are at risk of developing OPC.

Laryngeal dysplasia and narrow band imaging: Secondary analysis of published data supports the role in patient follow-up

BACKGROUND

Clinicians have recognised the role of narrow band imaging (NBI) in the management of head and neck cancer in several studies. However, a recent systematic review was unable to pool the data on diagnostic efficacy in this setting owing to the heterogeneity in the published data.

METHODS

Secondary analysis of data, utilising Bayes' theorem, from meta-analyses and randomised trials.

RESULTS

In patients with a histological diagnosis of mild dysplasia who show no abnormalities on NBI, the post-test probability of malignancy is estimated to be 2.3%, compared to 10.3% with conventional white light imaging (WLI). For severe dysplasia, similar post-test probabilities after NBI and WLI are estimated to be 8.0% and 29.7%, respectively. Post-test probabilities in this setting indicate the chance of missing malignancy following a negative NBI or WLI in patients who undergo no further intervention. This study also provides a nomogram designed for use in this setting.

CONCLUSIONS

This study identifies the evidence base for use of NBI in the follow-up for laryngeal dysplasia.

Intra and interobserver agreement of narrow band imaging for the detection of head and neck tumors

BACKGROUND

Narrow band imaging (NBI) in combination with white light endoscopy (WLE) has improved the accuracy for the diagnosis and follow-up of head and neck carcinomas by identifying changes in the vascular patterns of the mucosa. However, NBI evaluation is explorer-dependent and may be influenced by the learning curve. The aim of this study is to assess the intra and interobserver agreement of NBI and WLE at the office, under local anaesthesia, by either experienced or non-experienced observers.

METHODS

Eighty-seven images of head and neck lesions were routinely collected under WLE and NBI. A group of three experienced otolaryngologists and three medical students assessed the images after a brief training. No additional patient information was provided. The same protocol was repeated after three weeks. Intra and interobserver agreement were calculated with the kappa index.

RESULTS

NBI intraobserver agreement was substantial (κ = 0.62) and better than with WLE alone, which was moderate (κ = 0.57) in both groups. Interobserver agreement was moderate with WLE (κ = 0.58) and substantial with NBI (κ = 0.63). Both groups improved intraobserver and interobserver agreement with the implementation of NBI.

CONCLUSIONS

Intra and interobserver agreement with NBI for the evaluation of head and neck lesions are substantial, and improve the results of WLE alone in both, professionals and trainees.

A study on the value of narrow-band imaging (NBI) for the general investigation of a high-risk population of nasopharyngeal carcinoma (NPC)

Background

This study aims to explore the feasibility of narrow-band imaging (NBI) applied for the diagnostic screening of a high-risk population of nasopharyngeal carcinoma (NPC) and increase the accuracy rate of nasopharyngeal biopsy and the diagnosis rate of early-stage patients.

Methods

The positive high-risk population of NPC to EB virus antibody was followed up. At the same time, serological screening and pharyngorhinoscopy were carried out. The specific methods were as follows: (1) all subjects received nasopharyngeal examinations through both the HD endoscopic white light mode (WL) and NBI mode, (2) nasopharyngeal biopsy was conducted on positive subjects with microscopic examination, and, finally, (3) a comparative analysis was conducted between the biopsy pathology results and microscopy results. In addition, the following comparative indicators were recorded under different modes: sensitivity, specificity, accuracy, positive likelihood ratio, and negative likelihood ratio. Then, the area under the ROC curve and the kappa coefficient were calculated.

Results

A total of 115 subjects were detected to be positive by microscopic examination under the WL mode. Among these subjects, 19 subjects were diagnosed with NPC. In addition, 24 subjects were detected to be positive by microscopic examination under the NBI mode. Among these subjects, 23 subjects were diagnosed with NPC. Under the WL mode, the specific values of the comparative indicators were as follows: sensitivity, 82.61%; specificity, 0%; and area under the ROC curve, 0.413. Furthermore, the WL mode in the diagnosis on the high-risk population of NPC exhibited poor consistency with the biopsy pathology results (kappa coefficient = − 0.069). Under the NBI mode, the specific values of the comparative indicators were as follows: sensitivity, 100%; specificity, 98.96%; and area under the ROC curve, 0.995. Furthermore, the NBI mode in the diagnosis on the high-risk population of NPC exhibited relatively satisfactory consistency with the biopsy pathology results (kappa coefficient = 0.973). Therefore, the NBI mode is significantly superior to the WL mode.

Conclusion

NBI endoscopic examinations should be conducted on a routine basis for high-risk populations of NPC. This can decrease the frequency of biopsies and enhance diagnostic effects.

Screening for human papillomavirus-driven oropharyngeal cancer: Considerations for feasibility and strategies for research

The incidence and burden of human papillomavirus (HPV)‐driven oropharyngeal cancer is expected to increase for decades, thus motivating discussions regarding possibilities for screening. This article addresses issues related to the validity and timeliness of screening for HPV‐driven oropharyngeal cancer, and raises important questions, highlights deficits and confusion in the existing literature, and proposes needed steps in the research agenda.

Narrow band imaging for head and neck malignancies: Lessons learned from mistakes

BACKGROUND

The accuracy of white light endoscopy in combination with narrow band imaging (WLE + NBI) for diagnosis of squamous cell carcinoma (SCC) does not reach 100%. We evaluated the characteristics of the false-negative and false-positive cases.

METHODS

Five hundred thirty lesions of the upper airways were evaluated. The WLE was followed by NBI examination before performing a biopsy.

RESULTS

The false-negative lesions (7.36%) were represented by submucosal and non-SCC tumors. Among the 25 non-SCC tumors, 72% did not show any suspicious vascular pattern under NBI. The false-positive lesions (6.04%) were mainly represented by postradiotherapy mucosal changes, ulcers, and infections. Regarding papillomas, NBI accuracy reached 95.32%, although cases with dysplasia were difficult to distinguish from SCC.

CONCLUSION

The WLE + NBI improved diagnostic accuracy, but not all lesions were ideally evaluated with current defined patterns. An accurate anamnesis is mandatory, because, in some cases, it may be more relevant than the NBI pattern.

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.

Trans-oral robotic assisted tongue base mucosectomy for investigation of cancer of unknown primary in the head and neck region. The UK experience

OBJECTIVES

The diagnosis of cancer of unknown primary (CUP) in head and neck occurs when the treating clinicians have utilised all available diagnostic tests and failed to identify the origin of the disease. There is no agreed consensus on which diagnostic investigations to use, or the order in which to use them in, although broad recommendations exist. Small tumours arising in the tongue base can be below the limits of resolution of conventional diagnostic techniques. Given the difficulty in targeting the tongue base, current practice involves blind random biopsies, which leads to a variable detection rate. Robotically assisted surgical removal of the tongue base, tongue base mucosectomy (TBM) has been shown to improve diagnostic yield. This study reports the diagnostic hit rate for tongue base primaries using this technique.

DESIGN

Retrospective case review.

SETTING

UK Head and Neck Centres.

PARTICIPANTS

Patients presenting as an unknown primary, investigated with clinical examination, PET-CT and palatine tonsillectomy.

MAIN OUTCOME MEASURES

The detection of a primary site of head and neck cancer in the otherwise unknown primary tumour.

RESULTS

The primary tumour site was identified in the tongue base in 53% (n=17) of patients. In 15 patients the tumour was in the ipsliateral tongue base (88%) while in two cases (12%) the tumour was located in contra lateral tongue base.

CONCLUSIONS

Trans-oral robotic assisted TBM raises the possibility of identifying over 50% of tumours that would otherwise be classified as CUP. Identifying these in the contralateral tongue base has implications for treatment planning and outcome.

Early detection of squamous cell carcinoma in carcinogen induced oral cancer rodent model by ratiometric activatable cell penetrating peptides

OBJECTIVES

Ratiometric cell-penetrating-peptides (RACPP) are hairpin-shaped molecules that undergo cleavage by tumor-associated proteases resulting in measurable Cy5:Cy7 fluorescence ratiometric change to label cancer in vivo. We evaluated an MMP cleavable RACPP for use in the early detection of malignant lesions in a carcinogen-induced rodent tumor model.

METHODS

Wild-type immune-competent mice were given 4-nitroquinoline-oxide (4NQO) for 16weeks. Oral cavities from live mice that had been intravenously administered MMP cleavable PLGC(Me)AG-RACPP were serially imaged from week 11 through week 21 using white-light reflectance and Cy5:Cy7 ratiometric fluorescence.

RESULTS

In an initial study we found that at week 21 nearly all mice (13/14) had oral cavity lesions, of which 90% were high-grade dysplasia or invasive carcinoma. These high-grade lesions were identifiable with white light reflectance and RACPP Cy5:Cy7 ratiometric fluorescence with similar detectability, Area Under Curve (AUC) for RACPP detection was 0.97 (95% Confidence interval (CI)=0.92-1.02, p<0.001), sensitivity=89%, specificity=100%. In a follow up study, oral cavity lesions generated by 4NQO were imaged and histologically analyzed at weeks 16, 18 and 21. In this study we showed that RACPP-fluorescence detection positively identified 15 squamous cell carcinomas (in 6 separate mice) that were poorly visible or undetectable by white light reflectance.

CONCLUSIONS

RACPP ratiometric fluorescence can be used to accurately detect carcinogen-induced carcinoma in immunocompetent mice that are poorly visible or undetectable by white light reflectance.