Diagnostic Variability of Laryngeal Premalignant Lesions

Is Binary Grading Better Than WHO System for Grading Epithelial Dysplasia? A Systematic Review and Meta-Analysis

BACKGROUND

This meta-analysis summarizes the current evidence on the intra- and inter-observer agreement between WHO and the binary grading systems used to assess epithelial dysplasia (ED).

METHODS

A systematic search for observational studies that compared the level of agreement among pathologists between WHO and binary grading systems for ED was conducted using three databases: Medline, Scopus, and EBSCOhost. For the meta-analysis, summary estimations of kappa value (κ) and standard error (SE) were utilized.

RESULTS

The pooled analysis of observations by 46 pathologists from a total of eight studies showed better interobserver agreement in the interpretation of ED for the binary system (κ = 0.31; 95% confidence interval [CI], 0.23-0.40) in comparison with the WHO (κ = 0.14; 95% CI, 0.10-0.19). The intra-observer agreement was reported only by five studies and was also found to be higher for the binary system (κ = 0.44; 95% CI, 0.31-0.57) compared to the WHO (κ = 0.25; 95% CI, 0.11-0.39).

CONCLUSIONS

Our results validate that the binary system has better overall intra-observer and interobserver agreement than the WHO system. Further studies with larger cohorts are mandatory before clinically relevant conclusions are drawn, as evidence remains inadequate.

Malignant Transformation of Dysplastic Vocal Fold Lesions: A Systematic Review and Meta-Analysis

Importance

The reported rates of malignant transformation of dysplastic laryngeal lesions are highly variable, as is time to malignant degeneration.

Objective

To evaluate the rate of and time to malignant transformation of dysplastic laryngeal lesions based on the World Health Organization (WHO) dysplasia classification system.

Data Sources

PubMed, MEDLINE, Embase, CINAHL, CENTRAL, and Cochrane Reviews were searched from the date of database inception to June 8, 2023.

Study Selection

English-language articles assessing the rate of malignant transformation using the 2005 WHO dysplasia classification system were included in this systematic review and meta-analysis.

Data Extraction and Synthesis

The study was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Data extraction was performed by 2 independent investigators. Study quality was assessed using a validated quality tool. When possible, data were pooled using random-effects meta-analysis.

Main Outcome Measures

The primary outcome measure was the malignant transformation rate in each laryngeal dysplasia category. Secondary outcome measure was the time interval over which malignant transformation had occurred.

Results

A total of 5585 records were screened, 61 full texts were assessed, and 18 retrospective cohort studies with 3243 participants were included in the final review. The weighted pooled mean malignant transformation rates of mildly, moderately, and severely dysplastic lesions were 10.9%, 23.3%, and 30.5%, respectively. Malignant transformation rate of nondysplastic laryngeal lesions was 4.5%. Moderately and severely dysplastic lesions had significantly higher odds of malignant transformation compared with mildly dysplastic lesions (moderate: odds ratio [OR], 2.90 [95% CI, 2.06-4.09]; I2 = 0%; severe: OR, 3.42 [95% CI, 2.11-5.52]; I2 = 40%). Lesions without dysplasia had a significantly lower odds of malignant transformation compared with lesions with mild dysplasia (OR, 0.48; 95% CI, 0.28-0.81; I2 = 0%). The overall mean time to malignant transformation was 28.8 months (range, 22.0-35.6 months) for all dysplasia grades.

Conclusion and Relevance

This systematic review and meta-analysis found that the rate of malignant transformation increased with the grade of laryngeal dysplasia. Moderately dysplastic lesions were more likely to undergo malignant degeneration compared with mildly dysplastic lesions.

Diagnosis with confidence: deep learning for reliable classification of laryngeal dysplasia

BACKGROUND

Diagnosis of head and neck (HN) squamous dysplasias and carcinomas is critical for patient care, cure, and follow-up. It can be challenging, especially for grading intraepithelial lesions. Despite recent simplification in the last WHO grading system, the inter- and intraobserver variability remains substantial, particularly for nonspecialized pathologists, exhibiting the need for new tools to support pathologists.

METHODS

In this study we investigated the potential of deep learning to assist the pathologist with automatic and reliable classification of HN lesions following the 2022 WHO classification system. We created, for the first time, a large-scale database of histological samples (>2000 slides) intended for developing an automatic diagnostic tool. We developed and trained a weakly supervised model performing classification from whole-slide images (WSI). We evaluated our model on both internal and external test sets and we defined and validated a new confidence score to assess the predictions that can be used to identify difficult cases.

RESULTS

Our model demonstrated high classification accuracy across all lesion types on both internal and external test sets (respectively average area under the curve [AUC]: 0.878 (95% confidence interval [CI]: [0.834-0.918]) and 0.886 (95% CI: [0.813-0.947])) and the confidence score allowed for accurate differentiation between reliable and uncertain predictions.

CONCLUSION

Our results demonstrate that the model, associated with confidence measurements, can help in the difficult task of classifying HN squamous lesions by limiting variability and detecting ambiguous cases, taking us one step closer to a wider adoption of AI-based assistive tools.

Decrement of prognostic nutrition index in laryngeal diseases: from precancerous lesion to squamous cell carcinoma

BACKGROUND

Malnutrition and systemic inflammatory response have been confirmed to be important risk factors for various cancers.

OBJECTIVE

To compare pretreatment prognostic nutrition index (PNI) among patients with laryngeal squamous cell carcinoma (LSCC), laryngeal precancerous lesion (LPL) and laryngeal benign lesion (LBL).

METHODS

A total of 253 male patients with laryngeal lesions were divided into LBL, LPL with low risk (LPL (l)), LPL with high risk (LPL(h)), LSCC (i), LSCC (ii) and LSCC (iii) groups according to their histopathological findings and the TNM staging system. PNI and other clinical parameters were calculated. Kruskal-Wallis, Mann-Whitney U or Chi-square or Fisher's exact test were used for comparison of different parameters among groups. Logistic regression was performed to estimate the odds ratios (OR) and the corresponding 95% confidence intervals (CI).

RESULTS

The PNI in the LSCC group was significantly lower than those of the LBL and LPL groups (p = .013 and p = .004, respectively), and decreased from LPL(l) to LSCC (iii) (from 53.97 ± 3.69 to 50.02 ± 4.75). LPL patients with lower PNI values had a higher risk of LSCC, the OR was 0.91 (95% CI: 0.84, 0.97) for a one-unit decrease.

CONCLUSIONS

PNI could be a simple and reproducible marker for predicting the severity of laryngeal diseases.

Grading systems of oral cavity pre-malignancy: a systematic review and meta-analysis

PURPOSE

Oral potentially malignant disorders (OPMDs) may have varying degrees of oral epithelial dysplasia (OED). Traditional grading schemes separate OED into three-tiers (mild, moderate, and severe). Alternatively, a binary grading system has been previously proposed that stratifies OED into low-risk and high-risk categories based on a quantitative threshold of dysplastic pathologic characteristics. This systematic review evaluates the predictive value of a binary OED grading system and examines agreement between pathologists.

METHODS

This meta-analysis queried 4 databases (PubMed, Ovid-MEDLINE, Cochrane, and SCOPUS) and includes 4 studies evaluating binary OED grading systems. Meta-analysis of proportions and correlations was performed to pool malignant transformation rates (MTR), risk of malignant transformation between OED categories, and measures of interobserver agreement.

RESULTS

Pooled analysis of 629 lesions from 4 different studies found a six-time increased odds of malignant transformation in high-risk lesions over low-risk lesions [odds ratio (OR) 6.14, 95% 1.18-15.38]. Reported ORs ranged from 2.8 to 22.4. The overall MTR was 26.8%, with the high-risk and low-risk lesions having MTRs of 57.9% (95% CI 0.386-0.723) and 12.7% (95% CI - 0.210 to 0.438), respectively. Pooled unweighted interobserver kappa values for the binary grading system and three-tiered system were 0.693 (95% CI 0.640-0.740) and 0.388 (95% CI 0.195-0.552), respectively.

CONCLUSION

Binary grading of OED into low-risk and high-risk categories may effectively determine malignant potential, with improved interobserver agreement over three-tiered grading. Improved grading schemes of OED may help guide management (watchful waiting vs. excision) of these OPMDs.

Recent Changes of Classification for Squamous Intraepithelial Lesions of the Head and Neck

CONTEXT

- Interpretation of atypical squamous lesions of the head and neck has always been a nettlesome task for pathologists. Moreover, many different grading systems for squamous intraepithelial lesions have been proposed in past decades. The recent World Health Organization 2017 classification presents 2 types of 2-tier systems for laryngeal and oral precursor lesions.

OBJECTIVE

- To review the recent changes in classification and the clinical significance for squamous intraepithelial lesions of the head and neck.

DATA SOURCES

- Personal experience and data from the literature.

CONCLUSIONS

- The 2-tier grading system for laryngeal dysplasia, presented by World Health Organization in 2017, is expected to improve diagnostic reproducibility and clinical implication. However, the diagnostic criteria for low-grade dysplasia do not distinguish it clearly from basal cell hyperplasia. The World Health Organization 2017 classification of oral epithelial dysplasia remains unclear, and complicated and variable grading systems still make head and neck intraepithelial lesions difficult to interpret.

Laryngeal precursor lesions: Interrater and intrarater reliability of histopathological assessment

OBJECTIVE

The World Health Organization classification (WHOC) 2017 of low-grade versus high-grade laryngeal dysplasia recently replaced the previous WHOC 2005 of mild, moderate, and severe dysplasia and carcinoma in situ. Our objectives were to compare the interrater agreement of the WHOC 2017 with that of the WHOC 2005 and to test the intra-rater agreement of the WHOC 2005.

METHODS

Two expert head and neck pathologists rated 211 tissue samples that were initially diagnosed with laryngeal precursor lesions. The samples were rated twice according to the WHOC 2005 and once according to the WHOC 2017; estimates of interrater and intrarater agreements were calculated with kappa statistics.

RESULTS

The crude intrarater agreements using the WHOC 2005 were 0.93 for rater 1 and 0.62 for rater 2. The corresponding unweighted kappa values were 0.90 (95% confidence interval [CI], 0.86-0.95) for rater 1 and 0.43 (95% CI, 0.35-0.54) for rater 2, whereas the standard linear weighted kappa values were 0.93 (95% CI, 0.90-0.97) for rater 1 and 0.60 (95% CI, 0.53-0.69) for rater 2. The crude interrater agreement for the WHOC 2005 was 0.57, with a corresponding unweighted kappa value 0.38 (95% CI, 0.31-0.48) and a standard linear weighted kappa value 0.52 (95% CI, 0.42-0.60). The crude interrater agreement for the WHOC 2017 was 0.83, with a corresponding unweighted kappa value 0.45 (95% CI, 0.31-0.59) and a standard linear weighted kappa value 0.46 (95% CI, 0.30-0.60).

CONCLUSION

Our results indicate difficulties in providing reliable diagnosis of laryngeal precursor lesions, even with experienced head and neck pathologists and the application of a newly revised classification system.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:2375-2379, 2018.

[Reconstruction of the examination of the laryngeal carcinoma of Emperor Frederick III by Rudolf Virchow]

Rudolf Virchow is one of the founders of modern pathology, and many of his ideas on inflammatory and neoplastic diseases are still valid today. Even for Virchow, determination of malignancy was not always easy. As an example, the laryngeal disease of Crown Prince Frederick William, the later Emperor Frederick III, is presented.The clinical findings at the beginning of the disease were suggestive of a carcinoma, though an inflammatory lesion was also discussed. Several attempts were made to remove the lesion bioptically, but local recurrences occurred and the first tissue samples were not examined histopathologically. Since laryngeal tumour operations had a high mortality at that time, histopathologic examinations were made in order to decide for or against an operation. The samples taken after pre-treatment did not meet Virchow's criteria for determining a carcinoma. Contrary to the present concept of a carcinoma in situ-carcinoma sequence, Virchow's concept was based on the assumption that carcinomas are not derived from the epithelium, but arise from a mesenchymal-epithelial transformation from the connective tissue. The clinical suspicion of a laryngeal carcinoma was confirmed only shortly before the patient's death and later by a post-mortem examination.The question repeatedly asked is whether Virchow should have diagnosed a carcinoma at the beginning of the disease. The answer has been the same for more than a hundred years: the clinician is dissatisfied with the histopathological diagnosis, so the pathologist is to blame.

The usefulness of narrow-band imaging for the diagnosis and treatment of vocal fold leukoplakia

OBJECTIVE

This research was aimed to explore the efficacy of narrow-band imaging (NBI) on distinguishing the degree of dysplasia of vocal fold leukoplakia.

METHODS

Patients were examined by flexible endoscopy, under white light endoscopy (WLE) and NBI. 78 lesions were divided into two groups according to the NBI classification. Group 1: non-dysplasia (ND), including squamous hyperplasia with hyperkeratosis or parakeratosis; Group 2: squamous hyperplasia with mild or moderate dysplasia (MD) or severe dysplasia (SD), or carcinoma in situ (CIS).

RESULTS

The diagnostic accuracy of NBI for Group 1 and Group 2 was 69.70% (23/33) and 95.56% (43/45), respectively, and the kappa index was 0.711 and a p value < .05, which was considered statistically significant.

CONCLUSIONS

The NBI could roughly estimate the degree of dysplasia. Differentiating between ND, MD, SD, and CIS, which may be useful for clinicians on selecting suitable therapies.

Laryngeal Dysplasia, Squamous Cell Carcinoma, and Variants

Squamous cell carcinoma (SCC) is a malignant epithelial tumor showing evidence of squamous differentiation. It is the most common malignancy of the larynx, with several variants (verrucous, exophytic or papillary, spindle-cell, basaloid, acantholytic, adenosquamous) recognized, with well-established precursor lesions. Dysplasia is now separated into only low-grade and high-grade categories. Each SCC variant has unique cytomorphologic features and histologic differential diagnoses that are important to consider, as management and outcomes are different.

SOX 1, contrary to SOX 2, suppresses proliferation, migration, and invasion in human laryngeal squamous cell carcinoma by inhibiting the Wnt/β-catenin pathway

Sex-determining region Y (SRY)-box protein 1 (SOX 1) has been reported to have the inhibiting effects on various cancer cells; however, the expression and effect of SOX 1 on laryngeal squamous cell carcinoma (LSCC) have not been determined. Therefore, the aim of this study was to assess the anti-proliferation and metastatic effects of SOX 1 and its related mechanisms on LSCC. According to our present study, first, we found that overexpression of SOX 1 could significantly inhibit proliferation and promote apoptosis in Tu212 cells. Additionally, overexpression of SOX 1 suppressed the migration and invasion potential of Tu212 cells via regulating Wnt/β-catenin pathway. Finally, we demonstrated for the first time that overexpression of SOX 1 could downregulate the expression of SOX 2, and co-expression of SOX 1 and SOX 2 could reverse the anti-tumor effect of SOX 1. In conclusion, our studies suggested that SOX 1 suppressed cell growth and invasion in Tu212 cells by inhibiting Wnt/β-catenin pathway, and the anti-tumor effect of SOX 1 could be weakened by SOX 2, which may be a potential molecular basis for clinical treatment of LSCC.

MicroRNA-10a-5p and microRNA-34c-5p in laryngeal epithelial premalignant lesions: differential expression and clinicopathological correlation

This study was to analyze the dys-regulation of microRNA-10a-5p and microRNA-34c-5p and their correlations with clinicopathological characteristics of laryngeal epithelial premalignant lesions (LEPL). Quantitative real-time polymerase chain reaction was performed to detect the expression of microRNA-10a-5p and microRNA-34c-5p in 94 cases of LEPL and 47 controls. Retrospective follow-up data of all patients were collected and the correlation between the dys-regulation of microRNA-10a-5p/microRNA-34c-5p and clinicopathological characteristics was examined by linear regression analysis. Expression of microRNA-10a-5p was down-regulated in LEPL, showing statistical difference between low-risk lesion group and high-risk lesion group, while microRNA-34c-5p expression was up-regulated gradually in LEPL groups and dropped suddenly in squamous cell carcinoma group. In addition, the differential expression of microRNA-10a-5p is profiled with either LEPL grade or gender, showing a linear correlation; and microRNA-34c-5p expression is correlated with alcohol consumption in LEPL patients (P < 0.05). The dys-regulation of microRNA-10a-5p and microRNA-34c-5p in LEPL and their correlations with clinicopathological characteristics might provide important theoretical and experimental basis for LEPL classification and the two microRNAs can serve as more valuable markers in diagnosis and clinical management of LEPL.