Narrow band imaging for early diagnosis of epithelial dysplasia and microinvasive tumors in the upper aerodigestive tract

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.

A comparison of the efficacy of narrow band imaging and contact endoscopy in an early diagnosis of squamous malignancies of the upper aerodigestive tract

Background

This study aims to compare the efficacy of narrow band imaging (NBI) endoscopy and contact endoscopy in early diagnosis of squamous malignancies of upper aerodigestive tract.

Methods

This study was of 18 months duration, sample size 50, and carried out at tertiary care hospital. The patients were subjected initially to NBI endoscopy followed by contact endoscopy. Thereafter, the lesion was biopsied and subjected to histopathological examination as is done routinely. The images obtained were analyzed based on criteria proposed by earlier studies and compared with histopathological examination as gold standard.

Results

The sensitivity, specificity, and negative predictive values of NBI in early diagnosis of squamous malignancies of upper aerodigestive tract were high and better than contact endoscopy.

Conclusion

Endoscopic NBI is a noninvasive and promising tool used for in vivo differentiation between malignant and nonmalignant lesions of upper aerodigestive tract by using morphology of mucosal capillaries and is more efficacious than contact endoscopy. It can be employed as part of routine ENT examination in outpatient departments; however, it has got a learning curve associated with it.

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.

Role of Narrow Band Imaging Technology in the Diagnosis and Follow up of Laryngeal Lesions: Assessment of Diagnostic Accuracy and Reliability in a Large Patient Cohort

BACKGROUND

The aim of this study was to assess diagnostic accuracy and reliability of narrow band imaging (NBI) in the differential diagnosis of laryngeal premalignant lesion, early cancers and recurrences.

MATERIAL AND METHODS

We enrolled 231 patients who underwent endoscopic examination with white light endoscopy (WLE) + NBI and divided them into two groups, group A, without previous radiochemotherapy and group B, with previous radiochemotherapy. When indicated, we performed surgical biopsies to evaluate sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and likelihood of endoscopic examination comparing WLE alone and WLE + NBI.

RESULTS

A positive NBI lesion, compared with a negative NBI lesion, had a 29.68 (group A) and 13.96 (group B) times higher probability to be histologically positive (i.e., confirmed) compared with WLE alone improving the diagnostic accuracy. In group A, the NBI mode showed excellent sensitivity (95.0%), which was higher than WLE 2 mode (77.5%). However, the greatest differences were recorded regarding specificity (96.8% vs. 40.6%). In group B, both NBI alone and WLE + NBI mode showed a 94.1% specificity compared with WLE alone, which had a maximum specificity of 85.3%. The mode comparison between NBI and WLE in both groups showed a statistically significant difference, with p-values <0.0001.

CONCLUSIONS

NBI represents a reliable technology in challenging situations, especially in the context of post-radiotherapy or post-surgical mucosal changes showing a high NPV. NBI could reduce the number of unnecessary biopsies related to increased microvascular anomaly revelation, which could help to identify early-stage lesions suitable for minimally invasive surgery and, consequently, decrease hospital admissions.

Diagnostic Accuracy of Narrow Band Imaging in Patients with Oral Lichen Planus: A Prospective Study

OBJECTIVE

Oral lichen planus (OLP) is a chronic mucocutaneous immune-mediated disease affecting 1% to 4% of the worldwide population. Development of malignant lesions is reported but only affects a minority of patients. The aim of our study was to assess the diagnostic potential of narrow band imaging (NBI) in OLP patients; focusing on the identification of high-grade dysplasia/carcinoma in newly developed lesions.

METHODS

Prospective evaluation of 56 patients with histopathologic diagnosis of OLP and presenting newly developed lesions not responding to medical treatment. All lesions were assessed by high-definition (HD) white light (WL) and HD-NBI endoscopy. All patients underwent biopsy regardless of the appearance at HD-WL and HD-NBI. Histology was defined as "positive" in case of high-grade dysplasia or carcinoma.

RESULTS

Five lesions (9%) were diagnosed as high-grade dysplasia/carcinoma. In this setting, overall diagnostic potential of HD-NBI was optimal, with a sensitivity of 100% (95% CI, 48-100), specificity of 96% (95% CI, 86-99), negative predictive value of 100% (95% CI, not calculable), positive predictive value of 71% (95% CI, 39-91), and accuracy of 96% (95% CI, 88-100).

CONCLUSIONS

Despite the diffuse inflammatory pattern derived from OLP, NBI improved the diagnostic accuracy and the capability to detect high-grade dysplasia/carcinoma.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E1156-E1161, 2021.

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.

Efficacy of Transnasal Flexible Videoendoscopy With Narrow Band Imaging for Follow-Up of Patients After Transoral Laser Cordectomy

BACKGROUND AND OBJECTIVES

Transoral laser surgery is the optimal surgical treatment modality for the early stages of glottic cancer. To allow for further treatment to be as effective and as minimal as possible, persistent or recurrent tumors should be detected very soon. The main aim is to minimize the risk of necessity of performing a total laryngectomy. Flexible videoendoscopy with narrow band imaging (NBI) was recommended by the European Laryngological Society as a diagnostic method for the follow-up of patients treated for laryngeal cancer. Nevertheless, the efficacy of this technique has not been extensively studied in patients after transoral laser cordectomies for vocal fold cancer. The aim of this study was to evaluate the efficacy of in-office transnasal NBI flexible videoendoscopy in the follow-up of patients after transoral laser cordectomy for glottic cancer. We also focused on describing the specific characteristics of recurrent tumor appearance.

MATERIALS AND METHODS

The presented study was conceived as a prospective study. Ninety-four consecutive patients who underwent transoral laser cordectomy for severe dysplasia, Tis, T1, and T2 glottic cancer in the period from June 2010 to August 2015 were enrolled in the study. All patients were postoperatively regularly followed using transnasal videoendoscopic examinations with NBI. Whenever a suspect lesion was identified during in-office examination, its nature was proven histologically.

RESULTS

We discovered 23 suspect findings in 21 patients by means of flexible videoendoscopy with NBI. Fifteen (65.2%) of them were histologically confirmed as recurrent tumors, whereas in 8 (34.8%) of them, the recurrent tumor was not proven. In two patients, the recurrent tumor was evident on computed tomography or magnetic resonance imaging, but NBI endoscopy did not reveal relapsing disease. The rest (71 patients) were considered true negative. Of the 15 recurrent tumors detected by NBI-coupled videoendoscopy, 8 (53.3%) were identified as submucosal masses with nonsignificant or no vascular changes, 4 (26.7%) were noted as the progression of leukoplakia without visible vascular changes, only 2 (13.3%) showed typical vascular changes, and, in 1 (6.7%) case, evident, significantly exophytic tumor with pathological vascularization was discovered. The sensitivity, specificity, and positive and negative predictive values of the in-office transnasal videolaryngoscopy with NBI were calculated to be 88%, 92%, 71%, and 97%, respectively.

CONCLUSIONS

The results of the study demonstrate that transnasal endoscopy with NBI in an outpatient setting is an excellent method for the follow-up of patients after transoral laser cordectomy for glottic cancer. The method achieves high sensitivity, specificity, and negative predictive value and a slightly low positive predictive value. Nevertheless, we must bear in mind that recurrent tumors after previous endoscopic resection may have a completely different appearance than new tumors originating from previously untreated tissues. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

How we improve the transoral resection for oral and oropharyngeal cancer: the CO2 waveguide laser

PURPOSE

The main aim of this study was to evaluate the CO₂ waveguide laser (CO₂ WGL) with flexible fiber (Lumenis, Santa Clara, CA) in the treatment of oral and oropharyngeal cancers specifically focusing on the lateral thermal damage (LTD) induced by this instrument and therefore on the reliability of the analysis of frozen sections collected during margin mapping.

METHODS

A total of 48 patients with oral and oropharyngeal cancers from T1 to T4a were prospectively enrolled in the study. We collected data about LTD, pathologic tumor and node stage (pTNM), surgical intervention, kind of reconstruction (no flap, local vs free flap), need for tracheotomy and time of removal, postoperative complications (such as bleeding, mucosal dehiscence, and fistula), need for feeding tube and time of removal.

RESULTS

Mean LTD was 164.7 ± 92.4 μm. Comparing frozen section histology before and after formalin embedding we found 5 true positives, 170 true negatives, 4 false positives and 4 false negatives, with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 55.6%, 98%, 55.6%, 98%, and 96.1%, respectively.

CONCLUSION

CO₂ WGL is a very manageable tool, which allows a precise cut. However, its high costs, the inability to re-use the fibers and its low coagulation capability must be considered.

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

Purpose

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

Methods

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

Results

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

Conclusions

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

Probe-based confocal laser endomicroscopy for diagnosis of nasopharyngeal carcinoma in vivo

OBJECTIVES/HYPOTHESIS

Probe-based confocal laser endomicroscopy (pCLE) is a novel technique allowing real-time evaluation of the histological features of tissues in vivo at the cellular level. This study aimed to evaluate the feasibility of using pCLE in the diagnosis of nasopharyngeal carcinoma (NPC).

STUDY DESIGN

Feasibility study.

METHODS

In this study, the pCLE images of the lesions, as well as the surrounding or contralateral normal mucosa of the lesions, were acquired in vivo from each patient after intravenous injecting of 2.5 mL fluorescein. Biopsy specimens were collected at the imaged sites followed by a histopathological diagnosis by the pathologists, which was used as the gold standard. The pCLE images were compared to histopathological diagnosis of visualized sites by using sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV).

RESULTS

Diagnoses based on pCLE images correlated well with the gold standard diagnoses based on tissue histology. The overall sensitivity, specificity, PPV, and NPV for diagnosis of carcinoma versus nondysplasia were 93.8% (67.7%-99.7%), 90.5% (68.2%-98.3%), 88.2% (62.3%-97.9%), and 95.0% (73.1%-99.7%), respectively, and the four indices for pCLE diagnosis of dysplasia versus nondysplasia were 60.0% (17.0%-92.7%), 80.9% (57.4%-93.7%), 42.9% (11.8%-79.8%), and 89.5% (65.5%-98.2%), respectively. The overall sensitivity for diagnosis of carcinoma versus dysplasia was 93.8% (67.7%-99.7%), specificity was 40% (7.3%-83.0%), PPV was 83.3% (57.7%-95.6%), and the NPV was 66.7% (12.5%-98.2%).

CONCLUSIONS

CLE is a suitable and valid method for otolaryngologists to diagnose of NPC in vivo.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:897-902, 2019.

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.

Preliminary experience with 4K ultra-high definition endoscope: analysis of pros and cons in skull base surgery

During the last two decades endoscopic skull base surgery observed a continuous technical and technological development 3D endoscopy and ultra High Definition (HD) endoscopy have provided great advances in terms of visualisation and spatial resolution. Ultra-high definition (UHD) 4K systems, recently introduced in the clinical practice, will shape next steps forward especially in skull base surgery field. Patients were operated on through transnasal transsphenoidal endoscopic approaches performed using Olympus NBI 4K UHD endoscope with a 4 mm 0° Ultra Telescope, 300 W xenon lamp (CLV-S400) predisposed for narrow band imaging (NBI) technology connected through a camera head to a high-quality control unit (OTV-S400 – VISERA 4K UHD) (Olympus Corporation, Tokyo, Japan). Two screens are used, one 31" Monitor – (LMD-X310S) and one main ultra-HD 55" screen optimised for UHD image reproduction (LMD-X550S). In selected cases, we used a navigation system (Stealthstation S7, Medtronic, Minneapolis, MN, US). We evaluated 22 pituitary adenomas (86.3% macroadenomas; 13.7% microadenomas). 50% were not functional (NF), 22.8% GH, 18.2% ACTH, 9% PRL-secreting. Three of 22 were recurrences. In 91% of cases we achieved total removal, while in 9% near total resection. A mean follow-up of 187 days and average length of hospitalisation was 3.09 ± 0.61 days. Surgical duration was 128.18± 30.74 minutes. We experienced only 1 case of intraoperative low flow fistula with no further complications. None of the cases required any post- or intraoperative blood transfusion. The visualisation and high resolution of the operative field provided a very detailed view of all anatomical structures and pathologies allowing an improvement in safety and efficacy of the surgical procedure. The operative time was similar to the standard 2D HD and 3D procedures and the physical strain was also comparable to others in terms of ergonomics and weight.

Narrow band imaging for risk stratification of glottic cancer within leukoplakia

BACKGROUND

This study investigates relevance of narrow band imaging (NBI) in stratifying risk of malignant transformation within leukoplakia.

METHODS

We conducted a prospective analysis that included 62 patients with 91 changes of leukoplakia on vocal folds. The NBI was obtained before microsurgery. Categorization of the lesion as benign was made when vessels of surrounding epithelium were classified as type I, II, or IV according to Ni classification. If there were visualized intraepithelial papillary capillary loops of type V, the lesion was classified as malignant. Results were compared to the histopathological diagnosis.

RESULTS

The NBI assessment classified 75 lesions (82.4%) as benign and 16 (17.6%) as malignant. Histopathological results revealed the diagnosis of no dysplastic changes or low grade dysplasia in 77 cases (84.6%). Another 14 cases (15.4%) occurred with high-grade dysplasia, carcinoma in situ, and invasive cancer. Sensitivity, specificity, and accuracy of NBI in predicting malignancy within leukoplakia were 100%, 97.4%, and 97.8%, respectively. The kappa index was 0.92 (95% confidence interval 81.1%-100%).

CONCLUSION

The noninvasive procedure of an NBI endoscopy may be recommended as an accurate method in predicting the risk of malignant transformation within the vocal fold leukoplakia and, therefore, would be useful in the clinic for planning the patient's therapy.

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.