Inter-observer Agreement in Laryngeal Pre-neoplastic Lesions

Abstract

In this series, laryngeal preneoplastic lesions were evaluated by the classifications of the World Health Organization (WHOC), Ljubljana (LC) and squamous intraepithelial neoplasia (SINC) by multiple observers. The inter-observer agreement (IA) by WHOC for laryngeal lesions had been previously evaluated, but to the best of our knowledge, there are no data for LC and SINC. H&E stained slides from 42 laryngeal biopsies were evaluated by fourteen participants according to WHOC and LC, and SINC was additionally applied by 6. The results were analyzed statistically. The diagnoses which were favored by most participants for each case, according to WHOC, were as follows: squamous cell hyperplasia (n = 5; 12%), mild dysplasia (n = 11; 26.2%), moderate dysplasia (n = 12; 28.6%), severe dysplasia (n = 7; 16.7%), carcinoma in situ (n = 5; 12%), and invasive squamous cell carcinoma (n = 2; 4.8%). There was a significant difference between the participants for all three classifications; some participants gave lower or higher scores than the others. The mean correlation coefficients (MCC) of the participants were higher for WHOC compared to LC (0.55 ± 0.15 and 0.48 ± 0.14, respectively). The mean linear-weighted kappa (wKappa) values of participants were not significantly different (0.42 ± 0.10, 0.41 ± 0.12 and 0.37 ± 0.07 for WHOC, LC and SINC, respectively). The kappa values in this series are in agreement with those in previous literature for WHOC, and the similar results obtained for LC and SINC are novel findings. Although the MCC of WHOC was higher, as the wkappa was not significantly different, the findings in this series are not in favor of any of the classifications for better IA for preneoplastic laryngeal lesions.

Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: What is New in the 2017 WHO Blue Book for Tumours of the Hypopharynx, Larynx, Trachea and Parapharyngeal Space

“…The treatment approaches of cases classified according to these grading systems are not harmonized and their results have proved not to be comparable [6,9,46]. In recent inter-observer studies, in which pathologists used all three classifications, no significant advantage was found for any of the applied grading systems and inter-observer agreements among pathologists were not encouraging [47][48][49]. Despite a certain degree of subjectivity, grading precursor lesions in the upper aerodigestive tract remains the most important prognostic factor for the biological behaviour of disease and the leading guidance for clinicians in selecting appropriate treatment.…”

Biomarkers predicting malignant progression of laryngeal epithelial precursor lesions: a systematic review

“…First, histological grading of laryngeal epithelial precursor lesions is not highly reproducible. Both inter-observer and intra-observer reproducibility is poor, usually associated with a low non-weighted or weighted kappa statistic (j value) [7][8][9]. Second, the presence and degree of dysplasia do not reliably predict biological behavior.…”

Current Views and Perspectives on Classification of Squamous Intraepithelial Lesions of the Head and Neck

“…0.12 and 0.37 ? 0.007) were not significantly different for the WHO-dysplasia system, LC and SIN, respectively [13].…”

“…Preference depends on a pathologist's training, bias and local custom [5]. Numerous articles have reported attempts to evaluate the reliability and inter-observer agreement of these grading systems for oral and laryngeal SILs [6][7][8][9][10][11][12][13]. Some of them have also compared WHO grading systems with new proposals, such as a binary grading system and other classifications for oral lesions or, more widely, for the whole head and neck region (Table 1) [2,7,9,[15][16][17].…”