Epidermal growth factor receptor, c-erbB-2 and p53 overexpressions in epithelial hyperplastic lesions of the larynx

The role of CD133 expression of cancer stem cells on radiotherapy response in early stage glottic cancers

PURPOSE

To investigate the relationship between CD133 positivity and radiotherapy (RT) response in early stage glottic laryngeal cancers.

METHODS

Thirty seven patients with early-stage glottic laryngeal carcinoma who were treated with primary RT were evaluated. Patients with regular follow-up of at least 3 years were included in the study. Patients who had previously received chemotherapy for laryngeal surgery or underwent surgery were excluded. The patients were divided into two groups as recurrent and non-recurrent. These two groups were compared in terms of CD133 expression by immunohistochemical method.

RESULTS

There were 37 patients in the study. Ten patients had recurrence and seven (70%) had CD133 positive and three had CD133 negative. Of 27 patients who had no recurrence, 16 (59%) had CD133 positive and 11 (41%) had CD133 negative. 7 (70%) of ten patients with recurrence were found to be positive for CD133; There was no statistically significant difference between recurrent and non-recurrent patient groups in terms of CD133 positivity (p > 0.05). There was no correlation between the final CD133 score and recurrence status as well (p > 0.05).

CONCLUSION

There was no relationship between radiotherapy response and CD133 staining in early-stage glottic laryngeal cancers. It is the largest study about CD133 and RT sensitivity in early stage glottic carcinomas.

Developing Classifications of Laryngeal Dysplasia: The Historical Basis

During the last 60 years numerous significant attempts have been made to achieve a widely acceptable terminology and histological grading for laryngeal squamous intraepithelial lesions. While dysplasia was included in the pathology of the uterine cervix already in 1953, the term dysplasia was accepted in laryngeal pathology first after the Toronto Centennial Conference on Laryngeal Cancer in 1974. In 1963 Kleinsasser proposed a three-tier classification, and in 1971 Kambic and Lenart proposed a four-tier classification. Since then, four editions of the World Health Organisation (WHO) classification have been proposed (1978, 1991, 2005 and 2017). Several terms such as squamous intraepithelial neoplasia (SIN) and laryngeal intraepithelial neoplasia (LIN) are now being abandoned and replaced by squamous intraepithelial lesions (SIL). The essential change between the 2005 and 2017 WHO classifications is the attempt to induce a simplification from a four- to a two-tier system. The current WHO classification (2017) thus recommends the use of a two-tier system with reasonably clear histopathological criteria for the two groups: low-grade and high-grade dysplasia. Problems with interobserver variability apart, subjectivities and uncertainties remain, but to a lesser degree. Ongoing and additional molecular studies may help to clarify underlying events that will increase our understanding and possibly can facilitate our attempts to obtain an even better classification. The classification needs to be easier for the general pathologist to perform and easier for the clinician to interpret. These two objectives are equally important to provide each patient the best personalised treatment available for squamous intraepithelial lesions.

Current understanding of the tumor microenvironment of laryngeal dysplasia and progression to invasive cancer

PURPOSE OF REVIEW

This review examines the historical tumor progression genetic model of laryngeal carcinomas, from dysplasia to invasive carcinoma and the role of infiltrating immune and inflammatory cells as contributors to this process.

RECENT FINDINGS

Classically, the genetic model of carcinogenesis describes overexpression of oncogenes and/or silencing of tumor suppressor genes which, when combined with exposure to environmental carcinogens over the course of time, results in damage to cellular DNA. Increasing evidence indicates that innate and adaptive immune mediators also play an important role in tumor progression of laryngeal carcinomas. Cellular mediators of immune suppression are often over represented in the tumor microenvironment and these cells release cytokines, which perpetuate immune suppression allowing for tumor immune evasion.

SUMMARY

Future therapies targeting laryngeal malignancies should focus on a combined approach which targets both genetic variations and immune mediators.

Tissue microarray analysis of EGFR and HER2 oncogene copy number alterations in squamous cell carcinoma of the larynx

PURPOSE

To evaluate EGFR and HER2 copy number changes and to assess their significance to tumor progression in a large group of patients with larynx cancer through the construction of a tissue microarray (TMA) consisting of 1,385 biopsies.

METHODS

Fluorescent in situ hybridization (FISH) was applied to analyze the tumors. FISH was successful for EGFR in 1,080 (77.98%) and for HER2 in 683 (49.31%).

RESULTS

HER2 was amplified in 1.02% of cases. Amplification did not correlate with the tumor phenotype-clinical stage, and grade. The low frequency of amplification of HER2 oncogene in larynx tumors showed that the mechanism responsible for the high level of receptor overexpression still remains unclear in the majority of cases. Amplification of EGFR was found in 10.37% of cases. The analysis revealed a lack of correlation between amplification of the oncogenes and the tumor phenotype. We observed a lack of difference between the samples of primary tumors and advanced disease carcinomas--tumors with regional/distant metastases and recurrent tumors regarding oncogene amplification.

CONCLUSION

These results suggest that EGFR amplification is a relatively rare event in larynx carcinogenesis that obviously does not predispose to tumor progression.

Immunohistological comparison of the World Health Organization (WHO) and Ljubljana classifications on the grading of preneoplastic lesions of the larynx

There is still controversy about the classification of laryngeal preneoplastic lesions. In this study, we compared the World Health Organization (WHO) and Ljubljana histological classifications with regard to laryngeal epithelial hyperplastic-dysplastic lesions in a single series to determine their relation to statistically significant criteria when the mechanisms of neoplastic progression are considered. Emphasis was put on p53 expression, proliferative activity, and angiogenesis. Fifty-four laryngeal biopsies with preneoplastic changes were re-evaluated and classified according to both classifications. The streptavidin-biotin method was used for immunohistochemical staining for Ki-67, p53, and CD34 antibodies. A positive correlation was obtained between the histological categories and Ki-67, p53, and CD34 expressions using both classifications (Spearman's Correlation test). There was a significant difference between the histological categories of both the WHO and the Ljubljana classifications, when the expression of the three markers was compared (Kruskal Wallis test, p = 0.000 for each). Further evaluation revealed a statistically significant difference between all categories of both classifications, excluding the p53 overexpression scores and vessel counts in mild and moderate dysplasia categories (Mann-Whitney U-test, p = 0.209, and 0.091 respectively), and the p53 overexpression scores in severe dysplasia and carcinoma in situ categories (Mann-Whitney U-test, p = 0.249) of the WHO classification. Similarly, no significant differences were found between severe dysplasia and carcinoma in situ, as well as between atypical hyperplasia and carcinoma in situ categories using both classifications for the Ki-67 expression (Mann-Whitney U-test, p = 0.806, and 0.111, respectively). Our results suggest that regarding the mechanisms of neoplastic progression such as p53 expression and angiogenesis, the histological categories of the Ljubljana classification seem to depend on additional evidence. Therefore, we support the use of the Ljubljana classification.

The spectrum of laryngeal neoplasia: the pathologist's view

Several types of neoplastic change with different prognostic implications typically involve the laryngeal squamous epithelium. The purpose of this review is to examine the spectrum of these changes, as well as their relationship to benign squamous epithelial proliferative states. Since these pathological changes are apt to occur in regions where the epithelial lining is typically squamous, it is important to recognize that the epithelium of the larynx varies from stratified squamous to respiratory-type, depending on the location. The lingual (anterior) surface of the epiglottis is lined by a stratified squamous type, while the laryngeal (posterior) surface is stratified squamous merging into respiratory-type. In the larynx, the supraglottic and infraglottic portions are a respiratory-type, which contrasts with the stratified squamous epithelium of the glottis. This typical distribution does show some degree of variability in those patches of squamous epithelium and is frequently seen within the respiratory-type epithelial regions. The junction between the two epithelial types may be abrupt or separated by a transitional zone.

The expression of p53, c-erbB-1 and c-erbB-2 molecules and their correlation with prognostic markers in patients with head and neck tumors

Molecular prognostic and predictive factors have extensively been studied in different cancers during the past decades, some of which were found to be useful in diagnosis, follow up or even treatment of some malignant tumors. To assess the significance of c-erbB-1, c-erbB-2 and p53 expression in head and neck tumors among Iranian patients and their correlation with known prognostic factors, samples from 53 patients with squamous cell carcinomas of larynx and tongue were studied immunohistochemically. Strong immunoreactivity of c-erbB-1, c-erbB-2 and p53 was observed in 37 (70%), 40 (76%) and 37 (70%) of cases, respectively. The coexpression of these molecules was detected in 27 (50.9%) samples. Neither histological grading nor nodal involvement revealed correlation with c-erbB-1 and/or c-erbB-2 expression. No correlation was found between p53 expression and histological grade. However, a significant positive association was observed between p53 expression and nodal involvement. This data, which is the first report on head and neck squamous cell carcinomas (HNSCC) in Iran, indicates the significance of p53 protein expression which may result from p53 tumor suppressor gene inactivation in lymph node metastasis of HNSCC among Iranian patients.

Immunohistochemically stained markers (p53, PCNA, bcl-2) in dysplastic lesions of the larynx

The percentage of malignant transformation of laryngeal dysplastic lesions is difficult to estimate. There is a need for new histological markers which could enable more objective assessment of the premalignant stages of the larynx and help in estimation of the potential of future neoplastic progression. We performed a retrospective study to determine whether immunohistochemical staining for the proliferating cell nuclear antigen (PCNA), tumour suppressor gene protein p53 and antiapoptotic protein bcl-2 may be prognostic factors in laryngeal epithelial lesions. Staining was performed on 57 paraffin-embedded biopsies from patients with clinically detected precancerous stages of the larynx. Histopathologic examination revealed normal epithelium in six cases, mild dysplasia in 20 cases, moderate dysplasia in 18 cases, severe dysplasia in seven cases, CA in situ in four cases, papilloma in one case and CA invasivum in one case. The p53 count in mild and moderate dysplasia was 26.8 and 38.6%, respectively. This difference was statistically significant. There was significant correlation between PCNA and p53 scores. There was also a relationship between the scores of these markers and bcl-2 expression. In ten out of 45 cases of dysplastic lesions the invasive cancer developed in 4 years of follow-up. The correlation between PCNA score and malignant progression of the dysplastic lesions was on the statistical borderline. There was significant relationship between malignant transformation and age of the patients.