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.

The Role of Peritumoral Depapillation and Its Impact on Narrow-Band Imaging in Oral Tongue Squamous Cell Carcinoma

A recent study reported that the occurrence of depapillated mucosa surrounding oral tongue squamous cell carcinomas (OTSCC) is associated with perineural invasion (PNI). The present study evaluates the reliability of depapillation as a PNI predictor and how it could affect narrow-band imaging (NBI) performance. This is thus a retrospective study on patients affected by OTSCC submitted to radical surgery. The preoperative endoscopy was evaluated to identify the presence of depapillation. Differences in distribution between depapillation and clinicopathological variables were analyzed. NBI vascular patterns were reported, and the impact of depapillation on those was studied. We enrolled seventy-six patients. After evaluation of the preoperative endoscopies, 40 (53%) patients had peritumoral depapillation, while 59 (78%) had a positive NBI pattern. Depapillation was strongly correlated to PNI, 54% vs. 28% (p = 0.022). Regarding the NBI pattern, there was no particular association with depapillation-associated tumors. The presence of depapillation did not affect the intralesional pattern detected by the NBI, while no NBI-positive pattern was found in the depapillation area. Finally, the NBI-guided resection margins were not affected by depapillation. Peritumoral depapillation is a reliable feature for PNI in OTSCC. NBI margin detection is not impaired by depapillation.

Accuracy of narrow band imaging for detecting the malignant transformation of oral potentially malignant disorders: A systematic review and meta-analysis

Objective

Oral potentially malignant disorders (OPMDs) are a spectrum of diseases that harbor the potential of malignant transformation and developing into oral squamous cell carcinoma (OSCC). Narrow band imaging (NBI) has been clinically utilized for the adjuvant diagnosis of OPMD and OSCC. This study aimed to comprehensively evaluate the diagnostic accuracy of NBI for malignant transformations of OPMD by applying the intraepithelial papillary capillary loop (IPCL) classification approach.

Methods

Studies reporting the diagnostic validity of NBI in the detection of OPMD/OSCC were selected. Four databases were searched and 11 articles were included in the meta-analysis. We performed four subgroup analyses by defining IPCL I/II as negative diagnostic results and no/mild dysplasia as negative pathological outcome. Pooled data were analyzed using random-effects models. Meta-regression analysis was performed to explore heterogeneity.

Results

After pooled analysis of the four subgroups, we found that subgroup 1, defining IPCL II and above as a clinically positive result, demonstrated the most optimal overall diagnostic accuracy for the malignant transformation of OPMDs, with a sensitivity and specificity of NBI of 0.87 (95% confidence interval (CI) [0.67, 0.96], p < 0.001) and 0.83 [95% CI (0.56, 0.95), p < 0.001], respectively; while the other 3 subgroups displayed relatively low sensitivity or specificity.

Conclusions

NBI is a promising and non-invasive adjunctive tool for identifying malignant transformations of OPMDs. The IPCL grading is currently a sound criterion for the clinical application of NBI. After excluding potentially false positive results, these oral lesions classified as IPCL II or above are suggested to undergo biopsy for early and accurate diagnosis as well as management.

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.

[The application of NBI endoscopy in finding concealed primary lesions of misdiagnosis of oropharyngeal cancer]

Objective:The aim of this study is to analyze the application value of NBI endoscopy in finding the concealed primary lesions of misdiagnosis of oropharyngeal cancer. Methods:The clinical data of patients with missed oropharyngeal cancer treated in the Department of Otolaryngology Head and neck surgery, the Second Affiliated Hospital of Xi'an Jiaotong University from May 2018 to June 2021, were retrospectively studied, and the missed diagnosis was also analyzed combined with results of NBI endoscopy. Results:In 31 cases of misdiagnosis of oropharyngeal cancer patients, including 25 males and 6 females, there was no significant difference in age, BMI index, course of disease and TNM stage （P> 0.05）, and the pharyngeal or cervical symptoms were the first clinical manifestations of them, containing pharyngeal pain in 17 cases（54.8%） , pharyngeal foreign body sensation in 4 cases（12.9%） and unilateral cervical mass in 10 cases （32.3%）. No laryngoscopy was performed （21 cases） or no primary lesion was found by laryngoscopy （10 cases） at initial diagnosis. Among them, "inflammatory lesions" were given anti-inflammatory treatment with ineffective results or surgical resection was explored for suspicious lesions （17 cases）, or imaging examination （9 cases, including 6 cases with CT and MRI, 3 cases with PET-CT） and cervical lymph node biopsy （5 cases） were carried out for further diagnosis. According to these results, they were given ordinary laryngoscope （2 cases） or NBI endoscopy （29 cases） subsequently, finally they were confirmed as oropharyngeal squamous cellcarcinoma after localized biopsy at the suspicious lesions, indicating that the accuracy of NBI endoscopy in finding the concealed primary lesions of oropharyngeal cancer （93.55%） is significantly higher than that of ordinary electronic laryngoscope （6.45%）（χ²=43.613, P<0.01）. Conclusion:NBI endoscopy has unique advantages in finding oropharyngeal cancer in concealed parts such as tonsil, root of tongue, soft palate and lateral wall of oropharynx, which could reduce misdiagnosis of oropharyngeal cancer.

Leukoplakia: An Invasive Cancer Hidden within the Vocal Folds. A Multivariate Analysis of Risk Factors

Introduction

Discerning the preoperative nature of vocal fold leukoplakia (VFL) with a substantial degree of certainty is fundamental, seeing that the histological diagnosis of VFL includes a wide spectrum of pathology and there is no consensus on an appropriate treatment strategy or frequency of surveillance. The goal of our study was to establish a clear schedule of the diagnostics and decision-making in which the timing and necessity of surgical intervention are crucial to not miss this cancer hidden underneath the white plaque.

Material and Methods

We define a schedule as a combination of procedures (white light and Narrow Band Imaging diagnostic tools), methods of evaluating the results (a combination of multiple image classifications in white light and Narrow Band Imaging), and taking into account patient-related risk factors, precise lesion location, and morphology. A total number of 259 patients with 296 vocal folds affected by leukoplakia were enrolled in the study. All patients were assessed for three classifications, in detail according to Ni 2019 and ELS 2015 for Narrow Band Imaging and according to Chen 2019 for white light. In 41 of the 296 folds (13.9%), the VFL specimens in the final histology revealed invasive cancer. We compared the results from the classifications to the final histology results.

Results

The results showed that the classifications and evaluations of the involvement of anterior commissure improve the clinical utility of these classifications and showed improved diagnostic performance. The AUC of this model was the highest (0.973) with the highest sensitivity, specificity, PPV, and NPV (90.2%, 89%, 56.9%, and 98.3%, respectively).

Conclusion

The schedule that combines white light and Narrow Band Imaging, with a combination of the two classifications, improves the specificity and predictive value, especially of anterior commissure involvement.

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.

Validation of the European Laryngological Society classification of glottic vascular changes as seen by narrow band imaging in the optical biopsy setting

Purpose

In 2016, the European Laryngological Society (ELS) proposed a classification for vascular changes occurring in glottic lesions as visible by narrow band imaging (NBI), based on the dichotomic distinction between longitudinal vessels (not suspicious) and perpendicular ones (suspicious). The aim of our study was to validate this classification assessing the interobserver agreement and diagnostic test performance in detecting the final histopathology.

Methods

A retrospective study was carried out by reviewing clinical charts, preoperative videos, and final pathologic diagnosis of patients submitted to transoral microsurgery for laryngeal lesions in two Italian referral centers. In each institution, two physicians, independently re-assessed each case applying the ELS classification.

Results

The cohort was composed of 707 patients. The pathologic report showed benign lesions in 208 (29.5%) cases, papillomatosis in 34 (4.8%), squamous intraepithelial neoplasia (SIN) up to carcinoma in situ in 200 (28.2%), and squamous cell carcinoma (SCC) in 265 (37.5%). The interobserver agreement was extremely high in both institutions (k = 0.954, p < 0.001 and k = 0.880, p < 0.001). Considering the diagnostic performance for identification of at least SIN or SCC, the sensitivity was 0.804 and 0.902, the specificity 0.793 and 0.581, the positive predictive value 0.882 and 0.564, and the negative predictive value 0.678 and 0.908, respectively.

Conclusion

The ELS classification for NBI vascular changes of glottic lesions is a highly reliable tool whose systematic use allows a better diagnostic evaluation of suspicious laryngeal lesions, reliably distinguishing benign ones from those with a diagnosis of papillomatosis, SIN or SCC, thus paving the way towards confirmation of the optical biopsy concept.

Videomics: bringing deep learning to diagnostic endoscopy

PURPOSE OF REVIEW

Machine learning (ML) algorithms have augmented human judgment in various fields of clinical medicine. However, little progress has been made in applying these tools to video-endoscopy. We reviewed the field of video-analysis (herein termed 'Videomics' for the first time) as applied to diagnostic endoscopy, assessing its preliminary findings, potential, as well as limitations, and consider future developments.

RECENT FINDINGS

ML has been applied to diagnostic endoscopy with different aims: blind-spot detection, automatic quality control, lesion detection, classification, and characterization. The early experience in gastrointestinal endoscopy has recently been expanded to the upper aerodigestive tract, demonstrating promising results in both clinical fields. From top to bottom, multispectral imaging (such as Narrow Band Imaging) appeared to provide significant information drawn from endoscopic images.

SUMMARY

Videomics is an emerging discipline that has the potential to significantly improve human detection and characterization of clinically significant lesions during endoscopy across medical and surgical disciplines. Research teams should focus on the standardization of data collection, identification of common targets, and optimal reporting. With such a collaborative stepwise approach, Videomics is likely to soon augment clinical endoscopy, significantly impacting cancer patient outcomes.

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.

Quantification of structural and microvascular changes for diagnosing early-stage oral cancer

Changes in mucosal microvascular networks, called intraepithelial papillary capillary loops (IPCL), are an important key factor for diagnosing early-stage oral cancer in vivo. Nevertheless, there are a lack of tools to quantify these changes objectively. This is the first study to quantify the IPCL changes in vivo to differentiate benign or malignant oral lesions by the optical coherence tomography (OCT) technique. K14-EGFP-miR-211-GFP transgenic mice were inducted by 4-Nitroquinoline-1-oxide to produce oral carcinogenesis in different stages, including normal, premalignancy and cancer. The results showed significant differentiation between benign or malignant lesions by OCT quantitative parameters, including epithelial thickness, IPCL density, radius and tortuosity.

Real-time imaging of head and neck squamous cell carcinomas using confocal micro-endoscopy and applicable dye: A preliminary study

OBJECTIVES

Confocal laser endomicroscopy (CLE) is a technology that enables microscopic visualization of lesions in real-time (optical biopsy) and has been successfully applied for clinical use in gastroenterology. Recently, it was also introduced for head and neck squamous cell carcinoma (HNSCC) diagnostics. We previously designed a self-made CLE, which can provide bichrome images, with topical contrast agents that are safe for use in patients. Herein, we report findings of a pilot study using our self-made CLE to image pairs of normal and cancerous tissues. This study aimed to characterize the features of HNSCC compared with normal mucosa and to establish a methodology of in vivo real-time optical biopsy of HNSCCs.

METHODS

HNSCC tissues were acquired from 10 patients who underwent surgical resection. Dissected specimens were first evaluated for their auto-fluorescence spectral profiles with 473 nm laser excitation and further optical observation. While obtaining the image, auto-fluorescence spectrum and intensity of the reflectance fluorescent signals were measured in real-time by a spectrometer. Subsequently, acriflavine was applied to the specimen to fluorescently label the nuclei and observe the difference between normal and cancerous tissues with 473 nm laser excitation. Finally, double staining with acriflavine and edible Food Red No.106 was performed to observe both nuclei and the cytoplasm of normal and cancerous tissues at 473 nm and 561 nm laser excitation.

RESULTS

Lower signals were detected from auto-fluorescence images of cancer tissues than normal tissues with 473 nm laser excitation. After acriflavine application, there was a clear difference between cancer and normal mucosa in the uniformity of nuclear size and shape. In normal mucosa, cells were arranged in an orderly manner, with each cell resembling a frog's egg. By contrast, in cancer tissues, the cell density was higher, and the cellular arrangement was less orderly. Using both acriflavine and Food Red No.106, images became more vivid, but more complicated because red dye staining of the cytoplasm emerged as fluorescence at different wavelengths.

CONCLUSIONS

Real-time in vivo imaging using the newly developed CLE and conditions may be used to distinguish cancer tissue from normal mucosa without invasive biopsy.

Comparison of narrow band imaging and the Storz Professional Image Enhancement System for detection of laryngeal and hypopharyngeal pathologies

OBJECTIVE

The aim of this study was to compare narrow band imaging (NBI) endoscopy and Storz Professional Image Enhancement System (SPIES) in observing epithelial and/or subepithelial microvascular irregularities and pathologies.

METHODS

A total of 73 patients with laryngeal or hypopharyngeal lesions were investigated using high-definition NBI endoscopy preoperatively in local anesthesia and using SPIES system intraoperatively in general anesthesia from August 2016 to October 2017. Superficial vascular structures were classified preoperatively (NBI) and intraoperatively (SPIES) according to descriptive guidelines of vascular changes by Arens. All lesions were endoscopically evaluated and divided according to the histological examination into four groups (A-benign lesions, B-recurrent respiratory papillomatosis, C-low-grade dysplasia, D-high-grade dysplasia, carcinoma in situ or invasive squamous cell carcinoma), and results were compared with NBI and SPIES optical biopsy.

RESULTS

Benign lesions (polyps, cysts, chronic inflammation, hyperkeratosis) were histologically confirmed in 26/73 (35.6%) cases and identified by NBI in 20/26 lesions (76.9%) and in 20/26 cases (76.9%) by SPIES, respectively. Recurrent respiratory papillomatosis was confirmed in 16/73 (21.9%) and detected in 15/16 cases (93.8%) by NBI and in 16/16 cases (100.0%) by SPIES. Low-grade dysplasia (mild and moderate dysplasia) was histologically detected in 7/73 patients (9.6%) and accurately identified by NBI in 6/7 (85.7%) and by SPIES in 6/7 (85.7%) cases, respectively. Histopathological features of severe dysplasia, carcinoma in situ or invasive squamous cell carcinoma were detected in 24/73 (32.9%) patients. According to the NBI endoscopy the suspected vascular neoangiogenesis was recognized in 19/24 cases (79.2%) and in 18/24 cases (75.0%) using SPIES endoscopy. Sensitivity and specificity of NBI endoscopy and SPIES system in correct prediction of histological diagnosis of already detected lesions were 83.0 and 98.0% and 86.0 and 96.0%, respectively. Results of NBI/SPIES endoscopy and histopathological features of laryngeal and hypopharyngeal lesions were compared and the level of agreement was 81.43%, kappa index κ = 0.7428 (95% CI 0.682-0.832) (p < 0.001) by NBI endoscopy and 81.16%, kappa index κ = 0.7379 (95% CI 0.638-0.880) (p < 0.001) by SPIES endoscopy, respectively. The agreement was confirmed as substantial and strong. Level of agreement of both endoscopic methods was 92.54%, kappa index κ = 0.8965 (95% CI 0.877-0.954) (p < 0.001), agreement was confirmed as almost perfect. Between NBI and SPIES endoscopic imaging methods is no significant differentiation.

CONCLUSION

Both methods, NBI endoscopy and SPIES system, are comparable in detection and analysis of superficial neoangiogenesis, typical for benign lesion and for precancerous or cancerous changes in larynx and hypopharynx.

In-vivo optical imaging in head and neck oncology: basic principles, clinical applications and future directions

Head and neck cancers become a severe threat to human's health nowadays and represent the sixth most common cancer worldwide. Surgery remains the first-line choice for head and neck cancer patients. Limited resectable tissue mass and complicated anatomy structures in the head and neck region put the surgeons in a dilemma between the extensive resection and a better quality of life for the patients. Early diagnosis and treatment of the pre-malignancies, as well as real-time in vivo detection of surgical margins during en bloc resection, could be leveraged to minimize the resection of normal tissues. With the understanding of the head and neck oncology, recent advances in optical hardware and reagents have provided unique opportunities for real-time pre-malignancies and cancer imaging in the clinic or operating room. Optical imaging in the head and neck has been reported using autofluorescence imaging, targeted fluorescence imaging, high-resolution microendoscopy, narrow band imaging and the Raman spectroscopy. In this study, we reviewed the basic theories and clinical applications of optical imaging for the diagnosis and treatment in the field of head and neck oncology with the goal of identifying limitations and facilitating future advancements in the field.

Usefulness of office examination with narrow band imaging for the diagnosis of head and neck squamous cell carcinoma and follow-up of premalignant lesions

BACKGROUND

The purpose of this study was to evaluate the value of narrow band imaging (NBI) examination in the office for the diagnosis and follow-up of upper airway premalignant and malignant lesions.

METHODS

Four hundred eighty lesions were evaluated with white light endoscopy (WLE) and NBI before a biopsy/excision. Additionally, 151 premalignant lesions were followed up without proven biopsy. Carcinoma-free survival was calculated. The learning curve was analyzed.

RESULTS

Overall, the accuracy improved from 74.1% with WLE to 88.9% with NBI, being relevant in all anatomic subsites. The accuracy of NBI increased significantly with increasing experience (area under the curve [AUC] >0.9). After a follow-up of 25 months, 14 of 151 lesions (9.3%) converted into carcinoma. The 4-year carcinoma-free survival rate was 86.4%. The 4-year carcinoma-free survival rate differed significantly between lesions classified as benign/mild dysplasia versus those presenting as moderate/severe dysplasia (88.9% vs 73.5%; P = .018).

CONCLUSION

The NBI provided a greater accuracy than WLE and showed promising usefulness for the follow-up of premalignant lesions.

Narrow-band imaging in transoral laser surgery for early glottic cancer in relation to clinical outcome

BACKGROUND

The purpose of this study was to validate the prognostic value of adding narrow-band imaging (NBI) during transoral laser surgery (TLS) for early glottic cancer.

METHODS

In 84 patients, 93 transoral laser resections were performed for carcinoma in situ (Tcis), T1, or T2 glottic cancer. TLS was preceded by intraoperative evaluation using traditional white-light imaging (WLI) in 51 cases. In 42 cases, NBI was used in addition to WLI. Local recurrence rate and recurrence-free survival were retrospectively compared between both groups.

RESULTS

Local recurrences developed in 14% of the 93 cases: 12 of 51 patients (24%) were treated by TLS based on WLI alone, and in 1 of 42 patients (2%) in the NBI group (P < .01). Two-year recurrence-free survival was 82% in the WLI group and 98% in the NBI group (P < .05).

CONCLUSION

Additional use of NBI during TLS for early glottic cancer significantly improves clinical outcome.

Follow-up of oral and oropharyngeal cancer using narrow-band imaging and high-definition television with rigid endoscope to obtain an early diagnosis of second primary tumors: a prospective study

Narrow-band imaging (NBI) is an optical technique enhancing mucosal vasculature. The aim of this study is to assess the effectiveness of rigid NBI endoscopy in the early detection of second primaries or local recurrences after treatment for oral (OSCC) and oropharyngeal squamous cell carcinoma (OPSCC), its advantage over standard white-light (WL) endoscopy, and the influence of previous radiotherapy, the learning curve, and lesion site. Between January 2013 and June 2015, 195 patients treated for OSCC or OPSCC with surgery alone (group A) or radiotherapy with or without surgery and/or chemotherapy (group B) underwent additional follow-up assessments using NBI. Sensitivity, specificity, positive/negative predictive values (PPV and NPV), and accuracy for detecting second primaries or local recurrences were calculated for patients with at least two NBI assessments. The effect of previous radiotherapy was determined by test of proportions and that of the learning curve and lesion site with Fisher's exact test. 138/195 patients were included in the analysis. NBI sensitivity, specificity, PPV, NPV, and accuracy for groups A and B were 89.5 vs 100%, 85.2 vs 81.5%, 65.4 vs 69.7%, 96.3 vs 100%, and 86.3 vs 87%, respectively. The diagnostic gain of NBI was 88.2% in group A and 69.6% in group B. The learning curve was the main source of false positives (p = 0.025), whereas radiotherapy and lesion site were uninfluential (p = NS). NBI appears useful for follow-up after treatment for OSCC or OPSCC, its performance being affected only by the learning curve and not by previous treatment or lesion site.

Evaluation of the combined use of narrow band imaging and high-speed imaging to discriminate laryngeal lesions

BACKGROUND AND OBJECTIVE

Laryngeal lesions are usually investigated by microlaryngoscopy, biopsy, and histopathology. This study aimed to evaluate the combined use of Narrow Band Imaging (NBI) and High-Speed Imaging (HSI) in the differentiation of glottic lesions in awake patients.

STUDY DESIGN

Prospective diagnostic study.

MATERIALS AND METHODS

Thirty-six awake patients with 41 glottic lesions were investigated with both NBI and HSI, and the suspected diagnoses were compared to the histopathological results of tissue biopsies taken during subsequent microlaryngoscopies. Of the 41 lesions, 28 were primary lesions and 13 recurrent lesions after previous laryngeal pathologies.

RESULTS

Sensitivity, specificity, positive predictive value, and negative predictive value in the differentiation between benign/premalignant and malignant lesions with both NBI and HSI accounted to 100.0%, 79.4%, 50.0%, and 100.0%. Sensitivities and specificities were 100.0% and 85.7% for HSI alone, and 100.0% and 79.4% for NBI alone. Regarding only primary lesions the results were generally better with sensitivities and specificities of 100% and 81% for NBI, 100% and 84.2% for HSI and 100% and 85.7% for the combination of both methods, respectively.

CONCLUSION

NBI and HSI both seem to be promising adjunct tools in the differentiation of various laryngeal lesions in awake patients with high sensitivities. Specificities, however, were moderate but could be increased when using NBI and HSI in combination in a subgroup of patients with only primary lesions. Although both methods still have limitations they might ameliorate the evaluation of suspicious laryngeal lesions in the future and could possibly spare patients from repeated invasive tissue biopsies. Lasers Surg. Med. 49:609-618, 2017. © 2017 Wiley Periodicals, Inc.

The role of narrow-band imaging (NBI) endoscopy in optical biopsy of vocal cord leukoplakia

The aim of this study was to investigate whether observing microvascular changes by narrow-band imaging (NBI) endoscopy in the area surrounding leukoplakia is sufficient for discriminating between benign and malignant patterns of vocal cord leukoplakia. A total of 282 patients were investigated using white-light high-definition TV laryngoscopy and NBI endoscopy from 6/2013 to 8/2015, and 63 patients with a primary case of laryngeal leukoplakia were enrolled. Patients were divided into two groups based on leukoplakia with surrounding malignant intraepithelial papillary capillary loops (group I; 26/63) and leukoplakia with a surrounding benign vascular network (group II; 37/63), both by NBI endoscopy. All 63 patients were evaluated by blinded histological examination, and results were compared with NBI optical biopsy. Carcinoma in situ or invasive squamous cell carcinoma was confirmed in 22/26 cases (84.6 %) in group I. Hyperkeratosis or low-grade dysplasia was confirmed histologically in 31/37 (83.8 %) and squamous cell carcinoma in 2/37 (5.4 %) cases in group II. Accordance of NBI endoscopy and histopathological features of vocal cord leukoplakia lesions was statistically significant (kappa index 0.77, p < 0.001), with a sensitivity of 88.0 % (95 % CI 67.8-97.5 %) and specificity of 89.5 % (95 % CI 71.2-97.1 %). NBI is convenient for improving evaluation of laryngeal leukoplakias based on optic prehistological diagnosis. The close accordance between NBI features and histological results suggests that a negative NBI endoscopy may be an indication for long-term endoscopy follow-up without histological evaluation.

The diagnostic performance parameters of Narrow Band Imaging: A preclinical and clinical study

OBJECTIVES

The oral carcinoma is a widespread pathology and still presents poor prognosis. Among the available procedures for its early detection, Narrow Band Imaging technique allows to assess potential vascular network abnormalities. The reliability of this technique in the detection of dysplastic and neoplastic oral lesions was evaluated in a preclinical and clinical study.

MATERIALS AND METHODS

In the preclinical study, a chemical oral carcinogen was administered to 50 mice to induct both dysplastic and neoplastic oral lesions. In the clinical study 91 patients, bearing suspicious premalignant and malignant oral lesions, have been included. Images of animals' and patients' lesions were acquired under white and Narrow Band Imaging light prior to biopsy. Two expert raters examined the images and classified lesions, which were eventually compared to the histological diagnosis. The diagnostic performance included sensitivity, specificity, positive likelihood ratio, positive and negative predictive values, accuracy, percentages and degree of agreement between raters' evaluation and the histological report.

RESULTS

In the preclinical study sensitivity ranged from 0.57 to 1, specificity from 0.85 to 0.99, positive likelihood ratio from 6.54 to 65.04, positive predictive values from 0.32 to 0.96, negative predictive values from 0.91 to 1 and accuracy from 0.86 to 0.98. In the clinical study sensitivity ranged from 0.63 to 0.99, specificity from 0.89 to 1, positive likelihood ratio from 8.45 to 61.47, positive predictive values from 0.59 to 0.96, negative predictive values from 0.78 to 1 and accuracy from 0.82 to 0.99.

CONCLUSION

Narrow Band Imaging is an accurate technique, which holds a great potential for tumour angiogenesis evaluation and for the subsequent early detection of suspicious premalignant and malignant oral lesions.

The clinical diagnostic value of target biopsy using narrow-band imaging endoscopy and accurate laryngeal carcinoma pathologic specimen acquisition

OBJECTIVE

To estimate the clinical significance of target biopsy for clinical diagnosis and determine accurate laryngeal lesion pathologic specimen acquisition via narrow-band imaging (NBI) endoscopy.

METHODS

A total of 138 samples from patients with laryngeal lesions (carcinoma, 118; hyperplasia, 3; mild dysplasia, 2; moderate dysplasia, 5; severe dysplasia, 5; vocal cord polyp, 1; and inflammatory lesion, 4) were collected from the Department of Otolaryngology Head and Neck Surgery of Tianjin Union Medical Center from 1 January 2013 to 1 February 2015. All patients were divided into the regular biopsy and NBI target biopsy groups; the imaging data were recorded and patient samples were biopsied. Pathologic diagnoses were used to evaluate the accuracies of regular and target biopsy.

RESULTS

Based on the pathologic diagnosis, NBI target pathology yielded an accurate laryngeal lesion pathologic specimen acquisition rate of 95.6% (65/68), significantly higher than that yielded by regular biopsy (75.7%, 53/70; χ² = 10.99, P = 0.001). In the NBI target pathology group, the correct accurate pathologic specimen acquisition rates at laryngeal cancer diagnostic stages 0 (Tis), I and II were 100%, 100% and 85.71%, respectively, which were higher than the corresponding rates in the regular biopsy group (0%, χ² = 10.000, P = 0.002; 25%, χ² = 5.625, P = 0.018; and 38.46%, χ² = 6.454, P = 0.011, respectively).

CONCLUSIONS

In cases of laryngeal carcinoma, NBI endoscopy plays an important role in clinical diagnosis and accurate pathologic specimen acquisition and could be a regular clinical method for laryngeal lesion detection.

Narrow band imaging improves observer reliability in evaluation of upper aerodigestive tract lesions

OBJECTIVES/HYPOTHESIS

Visualization by endoscopy is essential in the diagnosis of upper aerodigestive tract lesions. Recent studies showed that narrow band imaging (NBI) increases the diagnostic potential of conventional white light imaging (WLI) by highlighting the superficial vessels. The objective of this study was to evaluate whether the use of NBI would influence inter- and intraobserver agreement while making diagnostic decisions using rigid endoscopy of the upper aerodigestive tract.

STUDY DESIGN

Retrospective study.

METHODS

One hundred routinely collected pictures of laryngeal, hypopharyngeal, and oropharyngeal lesions were used. Rigid endoscopies and patient data collection were performed according to standard protocol. Twelve observers, grouped in different levels of experience, assessed all lesions twice with a 2 to 4 week interval. Fleiss and Cohen's kappa (κ) values were calculated to assess inter- and intraobserver agreement.

RESULTS

Overall interobserver agreement increased from κ = 0.34 to κ = 0.40 by adding NBI to WLI (WLI and WLI + NBI, respectively). In experienced observers, an improvement from κ = 0.39 to κ = 0.43 was observed; in less-experienced observers an improvement from κ = 0.30 to κ = 0.37 was observed. Overall intraobserver agreement increased from moderate (κ = 0.54) to substantial (κ = 0.63) with addition of NBI. Intraobserver agreement for less-experienced observers improved remarkably when WLI was combined with NBI (κ = 0.51 vs. κ = 0.67).

CONCLUSIONS

Addition of NBI during rigid endoscopies of the upper aerodigestive tract led to improvement of both inter- and intraobserver agreement.

LEVEL OF EVIDENCE

4 Laryngoscope, 126:2276-2281, 2016.

The diagnostic value of narrow band imaging in different oral and oropharyngeal subsites

The diagnostic value of narrow band imaging (NBI) in the "optical biopsy" of leukoplakias (LP) and erythroplakias (EP) in different oral cavity (OC) and oropharyngeal (OP) subsites is still to be defined. We evaluated 128 unbiopsied and untreated OC/OP LP and EP by conventional oral examination (COE), white light (WL) endoscopy, and NBI and categorized them as "suspicious" or "innocuous". All lesions were treated by excisional biopsy. True positives were those considered as "suspicious" and with histopathology ranging from mild dysplasia to invasive carcinoma. Epithelia were classified as follows: type 1, keratinized thick stratified (gingiva, hard palate, dorsal tongue); type 2a, non-keratinized thin stratified (floor of mouth, vestibule, ventral tongue, soft palate, palatine tonsils, base of tongue); type 2b, non-keratinized, very thick stratified (retromolar trigon, lateral tongue, labial and buccal mucosa). Histopathology revealed 32 % benign lesions, 13 % mild to moderate dysplasias, 15 % severe dysplasias/carcinoma in situ, 16 % microinvasive, and 23 % invasive carcinomas. The false positive rates were 32 % at COE, 27 % at WL, and 15 % at NBI. The false negative rates were 49, 22, and 11 %, respectively. Diagnositic performance was higher for NBI compared to COE (p < 0.001) and to WL (p = 0.004). Comparison of the diagnostic value of NBI among different OC/OP subsites did not show statistically significant difference. NBI as an "optical biopsy" tool significantly reduces the rates of false positives and false negatives in diagnosis of OC/OP cancer compared with COE and WL. No statistically significant difference was noted in its diagnostic value among different OC/OP subsites.

Narrow band imaging: clinical applications in oral and oropharyngeal cancer

Narrow Band Imaging (NBI) is an endoscopic optical imaging enhancement technology that improves the contrast of mucosal surface texture, and enhances visualisation of mucosal and submucosal vasculature. White light is filtered to emit two 30-nm narrow bands of blue (415 nm) and green light (540 nm) light simultaneously, the former corresponding to the main peak absorption spectrum of haemoglobin, and the latter allowing visualisation of blood vessels in the deeper mucosal and submucosal layers. NBI has been used to better assess oral potentially malignant disorders (OPMD), identify oral and oropharyngeal squamous cell carcinoma (SCC), and to define surgical margins of head and neck malignancies. NBI shows great potential in improving detection rates of OPMD, facilitating better assessment of oral and oropharyngeal SCC, and reducing the risk of recurrence for oral SCC. Although further research is required to better understand and define intrapapillary capillary loop (IPCL) patterns and to relate these with clinical, histopathological and molecular parameters especially for early mucosal changes, there is building evidence to recommend its use as the new gold standard for endoscopic assessment in head and neck oncology.

Evaluation of the Dysphonic Patient (in: Function Preservation in Laryngeal Cancer)

The evaluation of the dysphonic patient begins with a complete understanding of the laryngeal anatomy and physiology of voice production. A thorough history must be taken regarding the dysphonia qualities, alarming symptoms, and confounding factors. The complete head and neck examination culminates in a detailed visualization of the vocal folds using image-capturing laryngoscopy as well as stroboscopy or high-speed digital imaging to fully evaluate the viscoelastic properties of the vocal fold cover-body structure and function. Finally, the evaluation leads to the biopsy of any concerning lesions either under magnification in the operating room or topical anesthesia in the office.

Light-emitting diode-assisted narrow band imaging video endoscopy system in head and neck cancer

Background/Aims

To validate the effectiveness of a newly developed light-emitting diode (LED)-narrow band imaging (NBI) system for detecting early malignant tumors in the oral cavity.

Methods

Six men (mean age, 51.5 years) with early oral mucosa lesions were screened using both the conventional white light and LED-NBI systems.

Results

Small elevated or ulcerative lesions were found under the white light view, and typical scattered brown spots were identified after shifting to the LED-NBI view for all six patients. Histopathological examination confirmed squamous cell carcinoma. The clinical stage was early malignant lesions (T1), and the patients underwent wide excision for primary cancer. This is the pilot study documenting the utility of a new LED-NBI system as an adjunctive technique to detect early oral cancer using the diagnostic criterion of the presence of typical scattered brown spots in six high-risk patients.

Conclusions

Although large-scale screening programs should be established to further verify the accuracy of this technology, its lower power consumption, lower heat emission, and higher luminous efficiency appear promising for future clinical applications.

Nasal mucosa narrow band imaging in granulomatosis with polyangiitis (Wegener granulomatosis): A preliminary study

BACKGROUND

Narrow band imaging (NBI) endoscopy is a technique that allows for real-time visualization of mucosal and submucosal vascular patterns.

OBJECTIVE

Because granulomatosis with polyangiitis (GPA) (Wegener granulomatosis) is an autoimmune disease defined by vascular inflammation, we examined patients with GPA and with NBI to evaluate whether disease-specific mucosal vascular patterns were present. To the best of our knowledge, the use of NBI endoscopy for assessment of an immune system disease such as GPA has never been previously attempted.

METHODS

We conducted a prospective observational study by performing an endoscopic evaluation of upper airways with NBI on patients diagnosed with GPA; on patients with symptoms and signs suggestive for GPA, who were scheduled to undergo nasal biopsy to confirm diagnosis; on patients affected by chronic rhinosinusitis with nasal polyps; and on healthy controls.

RESULTS

We enrolled 69 patients. NBI vascular patterns in patients with GPA were consistently and recognizably different from healthy mucosal patterns in 53% of our cases. In patients with GPA, biopsy and NBI results were for the most part comparable, except for three cases.

CONCLUSION

Nasal mucosa NBI endoscopy can be considered a promising rapid and noninvasive live imaging technique for nasal mucosa GPA that, based on further study, could become a supplementary diagnostic tool in the complex workup of GPA and vasculitis.

Narrow-Band Imaging of Laryngeal Images and Endoscopically Proven Reflux Esophagitis

Objective

To compare the difference between white light (WL) and narrow-band imaging (NBI) endoscopy in evaluating patients who had reflux laryngitis and esophagitis.

Study Design

Retrospective review of medical records and endoscopic images.

Setting

Outpatient clinic.

Subjects and Methods

There were 102 consecutive patients with reflux esophagitis (mean age, 48 ± 11 years) who had office-based transnasal esophagoscopy (TNE) with WL and NBI views, including 60 men (59%) and 42 women (41%). We compared WL and NBI endoscopy in observing the laryngeal and esophageal epithelium. The nasopharynx, base of the tongue, epiglottis, hypopharynx, larynx, esophagus, gastroesophageal junction, and stomach were examined, and all procedures were digitally recorded. All patients were evaluated with WL and NBI views to determine the reflux finding score (RFS) in the larynx and Los Angeles (LA) classification grade in the esophagus.

Results

The NBI views were more sensitive than the WL views in the erythema/hyperemia, vocal cord edema, and global RFS scores. The NBI view facilitated the identification of the erythema/hyperemia change representing dilation or proliferation of microvessels caused by epithelial inflammation. The global RFS score was significantly associated with severity of LA grade only with the NBI view.

Conclusion

The endoscopic findings with the NBI view permit an easier identification of the RFS parameters of laryngeal erythema/vocal cord edema, which have a stronger correlation with the severity of reflux esophagitis, than the WL view. The importance of NBI in the evaluation of reflux laryngitis and gastroesophageal reflux disease deserves further study.

Efficacy of narrow band imaging for detection and surveillance of potentially malignant and malignant lesions in the oral cavity and oropharynx: a systematic review

OBJECTIVE

Narrow band imaging (NBI) is an endoscopic technique that enhances the mucosal surface texture, and mucosal and submucosal vascular morphology. This paper systematically reviews the available literature regarding the efficacy of NBI for the detection and monitoring of potentially malignant and malignant lesions in the oral cavity and oropharynx.

METHODS

Databases searched included PubMed, EMBASE, Web of Science and Scopus (to September 2013). Additional articles were found by conducting an author publication search using PubMed and by scanning the reference lists of relevant articles. Only trials that investigated and evaluated the effectiveness of both white light (WL) and NBI for aiding the detection of only oral potentially malignant lesions, oral squamous cell carcinomas and/or oropharyngeal squamous cell carcinomas were considered for this review. Two reviewers (ANV and CSF) independently assessed retrieved articles against the criteria, and included articles underwent data extraction and risk of bias assessment.

RESULTS

Two studies, one retrospective and one prospective, met the inclusion criteria. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for WL ranged between 56-96%, 60-100%, 33-100%, 87-99% and 66-89% respectively, whereas it was 87-96%, 94-98%, 73-96%, 97-98% and 92-97% respectively for NBI.

CONCLUSION

While more research is required to determine the full value of NBI, it has great potential in accurately aiding the detection and assessment of neoplastic lesions, and influencing how these lesions are managed.

Perspectives on narrow-band imaging endoscopy for superficial squamous neoplasms of the orohypopharynx and esophagus

BACKGROUND AND AIM

Narrow-band imaging (NBI) is widely available and over the last decade has been applied as a detection and characterization technique for superficial neoplasms of the aerodigestive tract. The aims of the present study were to systematically review clinical trials of NBI endoscopy and to investigate an upgraded NBI system using a novel endoscope for superficial squamous neoplasms in the orohypopharynx and esophagus.

METHODS

Studies on the diagnostic use of NBI endoscopy for superficial squamous neoplasms in the orohypopharynx and esophagus were retrieved from MEDLINE and PubMed and reviewed. An upgraded NBI system using a novel endoscope was investigated with our clinical cases.

RESULTS

In many clinical trials, NBI endoscopy with or without magnification had high diagnostic value for superficial squamousneoplasms in the orohypopharynx and esophagus. An upgraded NBI system can produce a significantly brighter endoscopic view than conventional endoscopes with high-quality magnified images that could be used to diagnose superficial squamous neoplasms.

CONCLUSIONS

NBI endoscopy with or without magnification has diagnostic utility for superficial squamous neoplasms in the orohypopharynx and esophagus. The upgraded NBI endoscopic system is expected to facilitate the use of NBI and magnifying endoscopic diagnosis.

Advances in optical adjunctive AIDS for visualisation and detection of oral malignant and potentially malignant lesions

Traditional methods of screening for oral potentially malignant disorders and oral malignancies involve a conventional oral examination with digital palpation. Evidence indicates that conventional examination is a poor discriminator of oral mucosal lesions. A number of optical aids have been developed to assist the clinician to detect oral mucosal abnormalities and to differentiate benign lesions from sinister pathology. This paper discusses advances in optical technologies designed for the detection of oral mucosal abnormalities. The literature regarding such devices, VELscope and Identafi, is critically analysed, and the novel use of Narrow Band Imaging within the oral cavity is also discussed. Optical aids are effective in assisting with the detection of oral mucosal abnormalities; however, further research is required to evaluate the usefulness of these devices in differentiating benign lesions from potentially malignant and malignant lesions.

Observation as an option for epithelial positive margin after partial glossectomy in stage I and II squamous cell carcinoma: analysis of 365 cases

OBJECTIVE

This study was conducted to assess local recurrence and clinical prognosis in patients diagnosed as having a positive margin in the epithelial layer after a partial glossectomy treated by close observation.

METHODS

A total of 365 cases of squamous cell carcinoma of the tongue diagnosed as clinical Stage I or II, treated by partial glossectomy in the National Cancer Center Hospital East between 1992 and 2006, were studied retrospectively.

RESULTS

Pathological findings showed that 13 cases had positive margins in the epithelial layer, 4 (30.8%) of whom showed up with local recurrence in 4.4 years (3.0-5.0) on average. Lymph node recurrence was not observed and the 5-year overall survival rate was 76.2% in those 13 cases. The treatment for the recurrent cases was an additional partial glossectomy without neck dissection, which resulted in no recurrence and a survival rate of 100% after an average follow-up of 6.7 years.

CONCLUSIONS

We suggest careful observation as one option for cases diagnosed with epithelial positive margin.