Significance of eosinophil counting in tumor associated tissue eosinophilia (TATE)

Prognostic assessment of different methods for eosinophils detection in oral tongue cancer

BACKGROUND

TATE has been proposed as a prognostic factor in oral cancer staging; however, the controversial literature data limit its application in the routine diagnosis. The aim of this study was to evaluate the prognostic value of TATE in patients with oral tongue cancer. The second aim was to identify any difference in the methods of eosinophil quantification or in the cutoff values reported in literature.

METHODS

Clinic-pathological data of 204 patients treated at "Ospedali Riuniti" Hospital, Ancona, Italy, were collected. Evaluation of TATE was performed on hematoxylin-and-eosin-stained slides and correlation with survival outcomes was evaluated. The number of eosinophils per square millimeter was evaluated by using two methods, namely density (TATE-1) and classical (TATE-2) methods. For each of the 2 methods tested, patients were stratified into two or three groups, according to the most used cutoff values reported in literature.

RESULTS

Regardless of the method of eosinophil quantification or the cutoff values used, patients with high TATE had a significantly better disease-specific survival. The density method (TATE-1) showed a better predictive performance, in particular when applying a single cutoff of 67 eosinophils/mm² , two cutoffs of 10 and 100 eosinophils/mm² , or two cutoffs of 50 and 120 eosinophils/mm² .

CONCLUSION

The evaluation of TATE is simple, cost-effective, and easy to implement in daily practice with the aim of improving risk stratification of patients affected by oral tongue cancer. Results of prognostic performance analysis suggest using density (TATE-1) method as the standard approach to evaluate TATE in future studies, enhancing replicability.

Eosinophils as Major Player in Type 2 Inflammation: Autoimmunity and Beyond

Eosinophils are a subset of differentiated granulocytes which circulate in peripheral blood and home in several body tissues. Along with their traditional relevance in helminth immunity and allergy, eosinophils have been progressively attributed important roles in a number of homeostatic and pathologic situations. This review aims at summarizing available evidence about eosinophils functions in homeostasis, infections, allergic and autoimmune disorders, and solid and hematological cancers.Their structural and biological features have been described, along with their physiological behavior. This includes their chemokines, cytokines, granular contents, and extracellular traps. Besides, pathogenic- and eosinophilic-mediated disorders have also been addressed, with the aim of highlighting their role in Th2-driven inflammation. In allergy, eosinophils are implicated in the pathogenesis of atopic dermatitis, allergic rhinitis, and asthma. They are also fundamentally involved in autoimmune disorders such as eosinophilic esophagitis, eosinophilic gastroenteritis, acute and chronic eosinophilic pneumonia, and eosinophilic granulomatosis with polyangiitis. In infections, eosinophils are involved in protection not only from parasites but also from fungi, viruses, and bacteria. In solid cancers, local eosinophilic infiltration is variably associated with an improved or worsened prognosis, depending on the histotype. In hematologic neoplasms, eosinophilia can be the consequence of a dysregulated cytokine production or the result of mutations affecting the myeloid lineage.Recent experimental evidence was thoroughly reviewed, with findings which elicit a complex role for eosinophils, in a tight balance between host defense and tissue damage. Eventually, emerging evidence about eosinophils in COVID-19 infection was also discussed.

Tumor-associated tissue eosinophilia versus tumor associated blood eosinophilia: A ratio of diagnostic importance in oral squamous cell carcinoma

Introduction

Eosinophils are multifunctional granulocytes, which play a pivotal role in health and disease. Tumor Associated Tissue Eosinophilia (TATE) has long been evaluated in the diagnosis and progression of oral squamous cell carcinomas (OSCCs). However, their association with Tumor Associated Blood Eosinophilia (TABE) in OSCCs is still far fetched. We, therefore, attempted to evaluate their individual roles and to achieve a ratio between TATE and TABE in order to signify its usage in objectifying the diagnosis.

Materials and Methods

TATE was evaluated using H and E stain per 10 high power fields in 33 previously diagnosed cases of OSCC which were retrieved from department archives. TABE values were achieved from complete blood hemogram reports of patients. TATE/TABE ratio was calculated. All the parameters were clinicopathologically correlated and statistically evaluated using SPSS.

Results

TATE represented higher values in well-differentiated squamous cell carcinoma (WDSCC) and poorly differentiated squamous cell carcinoma (PDSCC) and was least in moderately differentiated squamous cell carcinoma (MDSCC), whereas TABE linearly increased from WDSCC to PDSCC. TNM Stage II cases revealed the highest TATE and lowest TABE. TATE/TABE ratio was the highest in WDSCC.

Conclusion

Due to the dual nature of eosinophils in early and late carcinogenesis events, evaluation of only TATE might not be conclusive in determining tumor grade. Hence, in a first of its kind attempt, the TATE/TABE ratio may be suitable to achieve a criterion for the determination of tumor grade and may also help to unfold the underlying biologic events.

Tumour-associated tissue eosinophilia (TATE) in oral squamous cell carcinoma: a comprehensive review

Oral squamous cell carcinoma is the most common head and neck malignancy, characterised by high invasive capacity, lymph node metastasis, and high recurrence rate. Among the morphological features of oral cancer, the tumour-associated tissue eosinophilia has gained growing interest in the last years. Eosinophils are a minor subpopulation of leukocytes, representing 1-3% of all circulating white blood cells. The presence of high levels of eosinophils is associated with several diseases, but their role in cancer pathophysiology is controversial. In particular, an uncertain and contradictory relationship exists between the exact role of tumour-associated tissue eosinophilia and oral cancer development. Many studies have shown that tumour-associated tissue eosinophilia increases both in the progression of oral potentially malignant disorders as well as in the grade and stage progression of oral cancer. Despite this, both negative and positive prognostic outcomes have been associated with eosinophil infiltration. The heterogeneous results may be partially due both to several methodological inconsistencies and to an incorrect interpretation of the physiological role of eosinophils. Therefore, further studies to elucidate the contribution of eosinophil infiltration are needed, focusing on the existence of eosinophil subpopulations regulated by the cancer immune microenvironment. Furthermore, the correct reporting of prognostic marker research is encouraged, in order to ensure the reproducibility and the comparability of the results from different studies.

Expression of CD34, VEGFR3 and eosinophil density in selected odontogenic tumors- a pilot study

Background

Limited statistically and clinically significant studies have been down on connective tissue factors in the odontogenic tumors. Therefore, the aim of this study was to determine the biological behavior of two selected epithelial odontogenic tumors (Ameloblastoma and Adenomatoid odontogenic tumor) by detecting CD34, VEGFR3 and eosinophil densities.

Methods

In this cross-sectional study, paraffin blocks including 20 cases of ameloblastoma and 20 (AOT), were selected. Totally, 4 sections were prepared for hematoxylin-eosin, Congo red staining, immunohistochemistry with CD34 and VEGFR3. Expression of VEGFR3, CD34 and lymphatic, blood vessels and eosinophil densities was examined.

Results

The mean of blood, lymphatic vessels and eosinophils densities in ameloblastoma were 14.9 ± 6.4, 4.4 ± 2 and 3.2 ± 2.7, respectively; and in AOT, they were 8.9 ± 3.4, 3.6 ± 1.3 and 1.2 ± 07, respectively. There was a significant difference in eosinophils and blood vessels densities between the two lesions (p = 0.005; p = 0.003). By increasing the density of eosinophils, the density of the blood vessels increased in both lesions (r = 0.539, P = 0.001) There was no positive relationship between eosinophils and lymphatic vessels densities in the two above mentioned odontogenic lesions (p = 0.288, R = 0.191).

Conclusion

It can be suggested that tumor angiogenesis and eosinophil densities may play a more effective role than lymphangiogenesis in local invasive behavior of ameloblastoma rather than AOT.

Eosinophil Density in Common Benign and Malignant Salivary Gland Tumors with Congo Red Staining

Purpose: Eosinophils are multifunctional leukocytes with unknown mechanisms in salivary gland tumors. Some researchers associate eosinophils with tumor progression and others have proposed them as antitumoral. The present study was conducted to compare the density of eosinophils in common salivary gland tumors and its relationship with the degree of differentiation in malignant salivary gland tumors. Materials and Methods: In this present descriptive-analytical, cross-sectional study, 15 cases of pleomorphic adenoma, 15 cases of adenoid cystic carcinoma (ACC), 30 cases of mucoepidermoid carcinoma (MEC), and 5 cases of normal salivary glands were extracted. Sections were prepared of these cases for Congo red staining. The malignant salivary gland tumors were classified as high-grade and low-grade malignancies. The slides were observed under ×10, and the highest-density areas were selected and counted in ten microscopic fields under ×40. Results: The density of the eosinophils was 4.5 ± 5.6 in the pleomorphic adenoma, 16.2 ± 6.01 in the low-grade MEC, 1.05 ± 1.1 in the high-grade MEC (Grade III), and the ACC, and 0.4 ± 0.89 in the normal salivary gland. Eosinophil density was significantly higher in low-grade malignancies compared to in benign or high-grade malignant neoplasms and normal salivary gland (P < 0.001). Conclusion: This is suggested which the density of eosinophils is associated with the process of tumorigenesis and the degree of malignancy in malignant salivary gland tumors.

Eosinophilia is a favorable prognostic marker for oral cavity and lip squamous cell carcinoma

Eosinophils are frequently encountered with squamous cell carcinomas (SCC) and it has been proposed that tumor-associated tissue eosinophilia (TATE) could be of prognostic significance in oral SCC. The aim was to evaluate TATE in 83 oral cavity and 16 lip SCCs as well as the best possible use of TATE as a prognostic marker. The number of eosinophils was counted per high power fields (HPF, ×400) in three different representative areas of the tumor and its stroma. The degree of TATE was analyzed in relation to clinicopathological features of tumors and patients' survival (follow-up mean 40.7 months) using Fisher's exact test. TATE was detected in 58 (70%) oral and 8 (50%) lip SCC samples. The median number of eosinophils between oral and lip SCC was different (p = 0.028) but TATE was similar per HPF (p = 0.085). Totally, 6% of lip and 21% of oral SCC patients died during the follow-up. The patients with the higher TATE had significantly better survival than the patients with the lower TATE (p = 0.0136). The best cut-off value predicting the survival was 4 eosinophils/HPF. TATE is a prognostic marker for oral and lip SCC: more than 4 eosinophils/HPF may predict more favorable prognosis.

Quantitative assessment of tumor-associated tissue eosinophilia and mast cells in tumor proper and lymph nodes of oral squamous cell carcinoma

Background

Oral squamous cell carcinoma (OSCC) is the most common cancer of the oral cavity. Tumor stage, thickness, lymph node metastasis (LNM), extranodal spread, perineural invasion, tumor differentiation, mutations, human papillomavirus infection and tumor microenvironment are independent prognostic indicators of OSCC. However, clinically, among all factors, LNM is considered an important prognostic factor in OSCC as it not only determines the stage of disease but also the strongest independent factor which predicts recurrence of disease. Further research proves that there are several biologically important factors in tumor tissue and LNs which promote or defend LNM. While it is proposed that tumor-associated tissue eosinophils (TATE) and mast cells (MCs) have "immuno-protective" effect, this remains unproven and various researchers have conflicting opinion.

Aim

The aim is to determine the presence of TATE and MCs in OSCC and to evaluate if any association exists between them and LNM.

Study Design

It is a comparative retrospective study between two groups including 35 OSCC cases positive and 35 negative for LNM.

Materials and Methodology

Quantification of cells was done by counting total number of cells in 10 high-power fields under ×40 objective lens using "zigzag" method and dividing it by total number of fields. Eosinophils stained bright red with carbol chromotrope and MCs purple-violet with toluidine blue.

Statistics

Independent t-test and Pearson's correlation were done using STATA IC 0.2 software. The level of significance was at 5%. Comparison of eosinophil and MC infiltration was done based on gender, metastatic, nonmetastatic LN and in tumor proper.

Results and Conclusion

Our study showed weak positive correlation between mean eosinophils count in tumor and LNs which implies a definite association between the microenvironment of tumor, its progression and LNM. There was a significant association between MC density and decreased LNM also. We conclude that an increased number of immunological cells (TATE and MCs) are a favorable prognostic indicator in OSCC. There is evidence of reduction in LNM with increasing density of these immunological cells. Recognition of TATE and MCs as integral to tumor biology opens an avenue for novel approaches to cancer therapies.

Evaluation of myeloid cells (tumor-associated tissue eosinophils and mast cells) infiltration in different grades of oral squamous cell carcinoma

Background:

The multifunctional involvement and infiltration of myeloid cells (tumor-associated tissue eosinophils [TATE] and mast cells) can provide a unique opportunity to define relevant effectors functions that may represent novel, therapeutic options for modulation of tumor onset/growth.

Aim:

Our study aimed to evaluate infiltration of myeloid cells (TATE and Mast cells) infiltration in different grades (WHO grading) of oral squamous cell carcinoma (OSCC).

Materials and Methods:

Total 30 cases of OSCC were selected for this study. Hematoxylin and eosin stain and toluidine blue special stain, to evaluate TATE and the mast cells infiltration, were used. Three-year follow-up of OSCC cases was done.

Result:

Among 30 cases, 63.33% cases of OSCC showed TATE-positive and 36.66% cases showed TATE-negative. Regarding mast cells infiltration, 66.66% OSCC cases showed mast cells positive and 33.33% cases did not show significant mast cells infiltration. We found significant association of TATE and mast cells infiltration in OSCC cases. These myeloid cells infiltration significantly associated with age of patients but did not show any significant association with gender, site, and habit of cases. When we compared these cells infiltration with clinical stages and different histological grades of tumor, we found their infiltration is decreasing, from Stages 1 to Stage 3 of tumor and from well to poorly differentiated carcinoma. We have also found the less infiltration of these myeloid in recurrence cases of OSCC.

Conclusion:

As the infiltration of TATE and mast cells are correlated, along with evaluation of TATE, we should also evaluate the presence of mast cells infiltration in OSCC. The assessment of myeloid cells could become, in the future, useful for therapeutic approaches in this subset of the patient.

Assessment of tissue eosinophilia as a prognosticator in oral epithelial dysplasia and oral squamous cell carcinoma-an image analysis study

Association of tissue eosinophilia with oral squamous cell carcinoma has shown variable results ranging from favourable to unfavourable or even having no influence on prognosis. Also, very few studies have been done to know the role of eosinophils in premalignancy. So the present study investigated role of eosinophilic infiltration in oral precancer and cancer and its possible use as a prognosticator. 60 histopathologically proven cases (20 cases each of metastatic and nonmetastatic oral squamous cell carcinoma and oral leukoplakia with dysplasia of various grades) were included. Congo red is used as a special stain for eosinophils. Each specimen slide was viewed under high power in 10 consecutive microscopic fields for counting of eosinophils. As a result, a significant increase in eosinophil count was found in oral carcinomas compared to dysplasia. Nonmetastatic cases showed higher counts than metastatic carcinomas. So, it is concluded that eosinophilia is a favourable histopathological prognostic factor in oral cancer. Moreover, higher eosinophil counts in carcinoma group compared to dysplasia group proved that they might have a role in stromal invasion thus suggesting that quantitative assessment of tissue eosinophilia should become a part of the routine histopathological diagnosis for oral precancer and OSCC.

Eosinophils in human oral squamous carcinoma; role of prostaglandin D2

Eosinophils are often predominant inflammatory leukocytes infiltrating oral squamous carcinoma (OSC) sites. Prostaglandins are secreted by oral carcinomas and may be involved in eosinophil infiltration. The objective of this study was to determine the factors contributing to eosinophil migration and potential anti-neoplastic effects on OSC. Eosinophil degranulation was evaluated by measuring release of eosinophil peroxidase (EPO). Eosinophil chemotaxis towards OSC cells was assessed using artificial basement membrane. Eosinophil infiltration was prominent within the tissue surrounding the OSC tumor mass. We observed growth inhibition of the OSC cell line, SCC-9, during co-culture with human eosinophils, in vitro, which correlated with EPO activity that possesses growth inhibitory activity. The PGD₂ synthase inhibitor, HQL-79, abrogated migration towards SCC-9. Our data suggest that OSC-derived PGD₂ may play an important role via CRTH2 (the PGD₂ receptor on eosinophils) in eosinophil recruitment and subsequent anti-tumor activity through the action of eosinophil cationic proteins.

Tumor-associated tissue eosinophilia as a prognostic factor in squamous cell carcinoma of the larynx

Inflammatory infiltration with eosinophilia in or around the tumoral tissue varies among the cases with invasive squamous cell carcinoma of the larynx. The aim of this study was to investigate the possible role of the tumor-associated tissue eosinophilia (TATE) as a predictive factor for the metastatic status in laryngeal squamous cell carcinoma in patients who had neck dissections. One hundred consecutive specimens from the patients who had been treated surgically for invasive squamous cell carcinoma of the larynx were re-evaluated in terms of TATE. Based on the eosinophil counts per 10 high power field (HPF), the cases were grouped into three different categories (I, II, III) according to three different cut off values (A, B, C). The number of eosinophil cells per 10 HPF for the groups were defined as: IA: 0-10; IB: 11-29; IC: 30 and greater; IIA: 0-20; IIB: 21-39; IIC: 40 and greater; IIIA: 0-30; IIIB: 31-49; IIIC: 50 and greater. Statistical significance between tissue eosinophil counts of the metastatic and non-metastatic lymph node groups were evaluated. This study comprised 97 male and three female patients with squamous cell carcinoma of the larynx (mean age 59.9). Forty-five were well differentiated, 50 were moderately differentiated and five were poorly differentiated invasive squamous cell carcinoma. At least one lymph node metastasis was observed in 34 cases. Eosinophil counts varied between 1 and 138 per 10 HPF in the tumor and/or peritumoral areas. In the three distinct categories with three different cut off values of eosinophil cell counts among nonmetastatic cases and cases with lymph node metastasis, correlation of eosinophil counts with lymph node metastasis were statistically insignificant (Crosstabs, χ(2)). Although in the series, numerical values of the TATE seem to be increased in patients with laryngeal squamous cell carcinoma with lymph node metastasis, this fact has not been confirmed with statistical analysis.

The role of eosinophils and eosinophil cationic protein in oral cancer: a review

Eosinophils are multifunctional leukocytes implicated in the pathogenesis of numerous inflammatory processes, such as allergies and parasitic infections. Increased number of these cells has been described in many human cancers, including oral squamous cell carcinoma, and its presence related to favourable as well as unfavourable prognosis. Although the exact role of eosinophils in tumours is not yet defined, the anti-tumour activity of these rare granulocytes has been associated with the release of their cytotoxic proteins, especially the eosinophil cationic protein, a single polypeptide chain with a molecular mass ranging from 15 to 22kDa encoded by the RNSE3 gene located on chromosome 14q11.2. Functional studies have implicated ECP in numerous processes, such as tissue remodelling in allergic inflammation; however its most striking function is the cytotoxic activity. The aim of this review is to summarise the role and functions of eosinophils and their granule-derived products in oral malignant tumours and the clinical value of the tumour-associated tissue eosinophilia for patients' prognosis.

Eosinophils and oral squamous cell carcinoma: a short review

The eosinophil cell has been related as a prognostic indicator for cancers. However, its exact function in tumour behaviour is still not clearly defined. In the oral cavity the presence of eosinophils can be a favourable prognostic indicator as well as it may be associated with a poor prognosis. In this short review, we briefly summarize the role of the eosinophils in the general context of immunoregulation and its relation to oral squamous cell carcinoma.

Prognostic significance of stromal eosinophilic infiltration in oral squamous cell carcinoma

Tumor-associated tissue eosinophilia (TATE) has been described in many sites, including head and neck. The aim of this study was to investigate the prevalence and possible role of TATE as a prognostic factor in oral squamous cell carcinoma (OSCC). Seventy-six consecutive patients with a diagnosis of OSCC were evaluated, and the number of eosinophils was obtained in 3 different areas in the tumor. The possible role of TATE as a prognostic factor in OSCC was investigated with respect to tumor differentiation; perineural, vascular, and muscular invasion (histopathologic parameters); and locoregional metastasis (clinical parameter). Tumor-associated tissue eosinophilia was low in most cases in 3 different areas. The mean eosinophil count was higher in the invasive front of tumor than intratumoral stroma and stroma subjacent the surface epithelium. The relations between TATE and tumor differentiation; perineural, vascular, and muscular invasion; and locoregional metastasis were not statistically significant (P > 0.05). Tumor-associated tissue eosinophilia has no correlation with prognostic parameters in OSCC.

Topographical distribution of bronchial eosinophilia: significance for biopsy diagnosis

Field-by-field (0.324 x 0.09 microM) counts of eosinophils were applied to the lamina propria of cartilaginous bronchi from 47 Los Angeles and 22 Miami residents 11 to 30 years of age who died suddenly from violence. A highly variable topographical distribution was found that appeared to be due mainly to variations in confluent eosinophil-positive fields and "hot spots" (>or=3 eosinophils per field). Since biopsy is the gold standard for the diagnosis of bronchial eosinophilia, there is a need to resolve the problem of non-uniformity. New measurements applicable to biopsy diagnosis are presented having potential usefulness for providing insight into the severity and topographical distribution of eosinophilia within bronchi that are the sites of biopsy. The additional finding of a 30.4% incidence of moderate to marked eosinophilia (>1.5 eosinophils/mm reticular basement membrane) suggests a high level of asthma or asthmatic-like disease in the young subjects of this study.

Significance of neo-angiogenesis and immuno-surveillance cells in squamous cell carcinoma of the tongue

Background

Neo-angiogenesis is an essential process in physiological and pathological conditions. However, it is a complex process. Several studies demonstrated that intra-tumoural microvessel number is a significant predictor of metastasis and clinical outcome in many tumours, including oral malignancies. The immuno-surveillance cells, mast cells and eosinophils are implicated in the biological behaviour of tumours. Nevertheless, their function in tissues is uncertain. Mast cells are involved in homeostatic regulation of blood vessels as well as host defence. In some malignancies, high mast cell density has been found to correlate with favourable prognosis. However, others reported unfavourable associations. Tumour associated tissue eosinophilia is a well-known phenomena. It has been associated with good and poor prognosis. However, the role of eosinophils in tumours remains controversial. Therefore, this study was designed to investigate the prognostic value of microvessel, mast cell and eosinophil densities in the context of clinico-pathological parameters and survival in squamous cell carcinoma of the tongue.

Materials and Methods

Anti-CD105 and anti-tryptase monoclonal antibodies were utilized to highlight and count microvessels and mast cells respectively in 81 cases of tongue squamous cell carcinoma. Eosinophils were demonstrated using carbol chromotrope histochemical stain. The densities were counted per mm2 and correlated with patients’ outcome and other clinico-pathological parameters using non-parametric tests and student's t-test. Clinically, the cases were divided into 4 main groups depending on survival time, lymph-node or distant metastasis.

Results

The 5 year survival was significantly lower in patients with a low mast cell density than those with a high density (p=0.006, Kruskal-Wallis test). The survival group-A demonstrated significantly higher mast cell and microvessel numbers than group-D (p=0.007, student's t-test) respectively. Patients with well- differentiated squamous cell carcinoma had significantly higher numbers of mast cells when compared to patients with poorly differentiated squamous cell carcinoma (p<0.05, student's t-test). The lymph node involvement correlation between the survival group-A and survival group-D was also significant (p=0.001, Mann-Whitney U test).

Conclusion

Data from this study indicates that accumulating mast cells in tumours play a part in inhibiting tumour progression and is potentially angiogenic in tumours.