Tumor-associated tissue eosinophilia in nasopharyngeal carcinoma. A pathologic study of 422 primary and 138 metastatic tumors

Rare case of metachronous tumor: Nasopharyngeal and colorectal carcinoma

The study presents an unusual case of a patient with a personal history of a rectal malignant tumor in 2013, who after a period of 6 years, was diagnosed with an advanced nasopharyngeal carcinoma, locally and regionally invasive. It is possible that the colorectal malignant tumor affected the development of the nasopharyngeal carcinoma, or the other way around, depending on the presence of genetic instabilities. These two types of malignant tumors share a series of genes that can influence their progression, i.e., SPINK-6 and Bcl-2. The particularity of this case stems from the development of a metachronous tumor, a rectal adenocarcinoma and nasopharyngeal carcinoma, two malignant tumors with different patient prognosis and disease progression. Research needs to be continued on the multidisciplinary therapeutic management of nasopharyngeal cancer and the ways of identifying this cancer type in its early stages, considering that most patients come from a rural environment, have poor medical education, a number of comorbidities, and who frequently ignore the signs, symptoms and sometimes the treatment offered.

Quantitative analysis of tumor-associated tissue eosinophils and tumor-associated blood eosinophils in oral squamous cell carcinoma

Background:

Stromal response to cancer is usually characterized by intense lymphoplasmacytic infiltrate. However, recently, the attention has shifted to tumor-associated tissue eosinophils (TATE). Tumor-associated blood eosinophils (TABE) are rare in solid cancers; however, carcinoma of the head and neck shows its prevalence.

Aim:

The aim of the study was to investigate the prevalence and relationship of tissue and blood eosinophils in various grades of oral cancer. The purpose of the article is to emphasize the possible clinical and biological significance of eosinophils in patients of oral squamous cell carcinoma (OSCC) so that appropriate therapeutic strategies can be devised accordingly.

Study Design:

Thirty histologically confirmed cases of oral squamous cell carcinoma were divided into well, moderate and poorly differentiated carcinoma. Eosinophilic infiltration in the tissue was graded as low, moderate and massive TATE. The number of eosinophils per 100 WBCs was taken as the differential eosinophil count. Blood eosinophilia (BE) >6% was considered to be TABE.

Materials and Methods:

Hematoxylin and eosin-stained tissue sections at 5 μ were evaluated. Prolonged staining in dilute 0.05% aqueous eosin demonstrated eosinophils selectively. Blood smears were stained by Leishman stain.

Statistical Analysis:

Student's t-test, Chi-square test, ANOVA, Newman–Keuls Multiple Comparison Test and Karl Pearson correlation coefficient® method were used.

Results:

The mean TATE value was highest in poorly differentiated carcinoma. TABE was seen only in a few cases and was associated mostly with poorly differentiated OSCC.

Conclusion:

There was a statistically significant correlation between TATE and histological grades of OSCC. Eosinophilia of the peripheral blood is an adverse sign in patients with carcinoma.

Deciphering the role of eosinophils in solid organ transplantation

Eosinophils are rare granulocytes that belong to the innate arm of the immune system. This cell population is traditionally defined as a destructive and cytotoxic mediator in asthma and helminth infection. Limited data in transplantation have suggested that eosinophils play a similar role in potentiating deleterious organ inflammation and immunologic rejection. Contrary to this long-held notion, recent data have uncovered the possibility that eosinophils play an alternative role in immune homeostasis, defense against a wide range of pathogens, as well as downregulation of deleterious inflammation. Specifically, translational data from small animal models of lung transplantation have demonstrated a critical role for eosinophils in the downregulation of alloimmunity. These findings shed new light on the unique immunologic features of the lung allograft and demonstrate that environmental polarization may alter the phenotype and function of leukocyte populations previously thought to be static in nature. In this review, we provide an update on eosinophils in the homeostasis of the lung as well as other solid organs.

Opposing roles of eosinophils in cancer

Eosinophils are a subset of granulocytes mostly known for their ability to combat parasites and induce allergy. Although they were described to be related to cancer more than 100 years ago, their role in tumors is still undefined. Recent observations revealed that they display regulatory functions towards other immune cell subsets in the tumor microenvironment or direct cytotoxic functions against tumor cells, leading to either antitumor or protumor effects. This paradoxical role of eosinophils was suggested to be dependent on the different factors in the TME. In addition, the clinical relevance of these cells has been recently addressed. In most cases, the accumulation of eosinophils both in the tumor tissue, called tumor-associated tissue eosinophilia, and in the peripheral blood were reported to be prognostic markers for a better outcome of cancer patients. In immunotherapy of cancer, particularly in therapy with immune checkpoint inhibitors, eosinophils were even shown to be a potential predictive marker for a beneficial clinical response. A better understanding of their role in cancer progression will help to establish them as prognostic and predictive markers and to design strategies for targeting eosinophils.

Allergic diseases: From bench to clinic - Contribution of the discovery of interleukin-5

T helper 2 cells produce a number of cytokines including inteleukin (IL)-5, IL-4 and IL-13. Group 2 innate lymphoid cells (ILC2s) also produce IL-5 under sterile conditions. IL-5 is interdigitating homodimeric glycoprotein and a member of the four α helical bundle motifs conserved among hematopoietic cytokines. IL-5 exerts its effects on target cells via IL-5 receptor (IL-5R), composed of an IL-5R α and βc subunit. The membrane proximal proline-rich motif of the cytoplasmic domain of both IL-5R α and βc subunits is essential for IL-5 signal transduction. Although IL-5 was initially identified by its ability to support the growth and terminal differentiation of mouse B cells into antibody-secreting cells, recombinant IL-5 exerts pleiotropic activities on various target cells. For example, IL-5 is now recognized as the major maturation and differentiation factor for eosinophils in mice and humans. Overexpression of IL-5 in mouse significantly increases eosinophil numbers and antibody levels in vivo, while mice lacking a functional gene for IL-5 or IL-5R display developmental and functional impairments in B cell and eosinophil lineages. In mice, the role of the IL-5/IL-5R system in the production and secretion of Immunoglobulin (Ig) M and IgA in mucosal tissues has been reported. Although eosinophils protect against invading pathogens including virus, bacteria and helminthes, they are also involved in the pathogenesis of various diseases, such as food allergy, asthma, and inflammatory bowel diseases. The recent expansion in our understanding in the context of IL-5 and IL-5-producing ILC2s in eosinophil activation and the pathogenesis of eosinophil-dependent inflammatory diseases has led to advances in therapeutic options. A new therapy currently under invetigarion in clinical trials uses humanized monoclonal antibodies against IL-5 or the IL-5R. In this review, we summarize our current understanding of the functions of IL-5 and its receptor, the innate regulation of IL-5-producing cells, and therapeutic potential of anti-IL-5 and anti-eosinophil (IL-5R) antibodies.

The Microenvironment in Epstein-Barr Virus-Associated Malignancies

The Epstein–Barr virus (EBV) can cause a wide variety of cancers upon infection of different cell types and induces a highly variable composition of the tumor microenvironment (TME). This TME consists of both innate and adaptive immune cells and is not merely an aspecific reaction to the tumor cells. In fact, latent EBV-infected tumor cells utilize several specific mechanisms to form and shape the TME to their own benefit. These mechanisms have been studied largely in the context of EBV+ Hodgkin lymphoma, undifferentiated nasopharyngeal carcinoma, and EBV+ gastric cancer. This review describes the composition, immune escape mechanisms, and tumor cell promoting properties of the TME in these three malignancies. Mechanisms of susceptibility which regularly involve genes related to immune system function are also discussed, as only a small proportion of EBV-infected individuals develops an EBV-associated malignancy.

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.

Eosinophils: The unsung heroes in cancer?

Prolonged low-grade inflammation or smoldering inflammation is a hallmark of a cancer. Eosinophils are components of the immune microenvironment that modulates tumor initiation and progression. Although canonically associated with a detrimental role in allergic disorders, these cells can induce a protective immune response against helminthes, viral and bacterial pathogens. Eosinophils are a source of anti-tumorigenic (e.g., TNF-α, granzyme, cationic proteins, and IL-18) and protumorigenic molecules (e.g., pro-angiogenic factors) depending on the milieu. In several neoplasias (e.g., melanoma, gastric, colorectal, oral and prostate cancer) eosinophils play an anti-tumorigenic role, in others (e.g., Hodgkin's lymphoma, cervical carcinoma) have been linked to poor prognosis, whereas in yet others they are apparently innocent bystanders. These seemingly conflicting results suggest that the role of eosinophils and their mediators could be cancer-dependent. The microlocalization (e.g., peritumoral vs intratumoral) of eosinophils could be another important aspect in the initiation/progression of solid and hematological tumors. Increasing evidence in experimental models indicates that activation/recruitment of eosinophils could represent a new therapeutic strategy for certain tumors (e.g., melanoma). Many unanswered questions should be addressed before we understand whether eosinophils are an ally, adversary or neutral bystanders in different types of human cancers.

Bidirectional Mast Cell-Eosinophil Interactions in Inflammatory Disorders and Cancer

Human mast cells (MCs) and eosinophils were first described and named by Paul Ehrlich. These cells have distinct myeloid progenitors and differ morphologically, ultrastructurally, immunologically, biochemically, and pharmacologically. However, MCs and eosinophils play a pivotal role in several allergic disorders. In addition, these cells are involved in autoimmune disorders, cardiovascular diseases, and cancer. MCs are distributed throughout all normal human tissues, whereas eosinophils are present only in gastrointestinal tract, secondary lymphoid tissues, and adipose tissue, thymus, mammary gland, and uterus. However, in allergic disorders, MCs and eosinophils can form the "allergic effector unit." Moreover, in several tumors, MCs and eosinophils can be found in close proximity. Therefore, it is likely that MCs have the capacity to modulate eosinophil functions and vice versa. For example, interleukin 5, stem cell factor, histamine, platelet-activating factor (PAF), prostaglandin D2 (PGD2), cysteinyl leukotrienes, and vascular endothelial growth factors (VEGFs), produced by activated MCs, can modulate eosinophil functions through the engagement of specific receptors. In contrast, eosinophil cationic proteins such as eosinophil cationic protein and major basic protein (MBP), nerve growth factor, and VEGFs released by activated eosinophils can modulate MC functions. These bidirectional interactions between MCs and eosinophils might be relevant not only in allergic diseases but also in several inflammatory and neoplastic disorders.

Prognostic significance of stromal eosinophilic infiltration in cancer of the larynx

OBJECTIVE: To investigate prevalence and possible role of tumor-associated tissue eosinophilia (TATE) as a prognostic factor in laryngeal squamous cell cancer.

STUDY DESIGN: Prospective case series.

METHODS: Seventy-eight consecutive patients with diagnosis of squamous cell carcinoma of the larynx and who were treated surgically in our center were evaluated. The possible role of TATE as a prognostic factor in laryngeal squamous cell cancer was investigated with respect to tumor differentiation, depth of invasion, perineural and vascular invasion (histopathological parameters), and neck metastasis (clinical parameter). The relation between presence of TATE and age was also examined.

RESULTS: TATE was positive in the tumors of 32% of the patients, including low grade, 20 (26%); medium grade, 4 (5%); and high grade, 1 (1%). The relationships between TATE and tumor differentiation, perineural invasion, vascular invasion, pathologic N stage, and depth of invasion were not statistically significant ( P >0.05). According to Spearman correlation analysis ( r = −0.383, P = 0.001), there is a negative correlation between TATE and age. Ages of TATE-positive patients tend to be clustered in the 5th and 6th decades of life, whereas the TATE-negative patients’ ages tend to be clustered in the 6th and 7th decades.

CONCLUSIONS: TATE has no correlation with prognostic parameters in laryngeal squamous cell cancer. Presence of TATE is highly correlated with age. Incidence of TATE is very low over the age of 60 years, and this may suggest that age influences the tissue inflammatory response to tumor. Further investigation is needed to explain the associations of TATE and age and also the host response to malignancy.

Comparative evaluation of eosinophils in normal mucosa, dysplastic mucosa and oral squamous cell carcinoma with hematoxylin-eosin, Congo red, and EMR1 immunohistochemical staining techniques

Background:

Oral squamous cell carcinoma is the most common malignant lesion of the oral cavity, and it involves various molecular mechanisms. The development of oral squamous cell carcinoma is influenced by the host immune cells, such as eosinophils. The present study was conducted to compare the presence of eosinophils in normal mucosa, dysplastic mucosa, and oral squamous cell carcinoma by -hematoxylin- eosin staining, Congo red staining, and epidermal growth factor-like (EGF-like) module containing a mucin–like hormone receptor1 (EMR1) immunohistochemical marker.

Methods:

In this cross-sectional study, 60 paraffinized samples were selected, consisting of 20 normal mucosae, 20 dysplastic mucosae, and 20 squamous cell carcinoma samples. After confirmation of the diagnosis, the mean number of eosinophils was evaluated by hematoxylin-eosin, Congo red, and immunohystochemical staining techniques. The data were analyzed by SPSS-10 software using the Kruskal-Wallis and Friedman tests.

Results:

The results showed that the number of eosinophils in dysplastic mucosa was significantly higher than the number in normal mucosa, and the number of eosinophils in squamous cell carcinoma was significantly higher than the number in dysplastic mucosa in all staining techniques (p<0.001). Moreover, the comparison of staining techniques showed a significantly higher number of eosinophils in EMR1immunohistochemicalmarker than were observed when Congo red and hematoxylin - eosin (H&E) staining techniques were used (p<0.001).

Conclusion:

It can be argued that eosinophil contributes to the identification of lesions that have a higher potential of malignant transformation. Moreover, eosinophil can be suggested as an indicator in the differentiation of oral lesions in cases with borderline diagnosis and in targeted molecular therapy.

Squamous cell carcinoma variants of the upper aerodigestive tract: a comprehensive review with a focus on genetic alterations

CONTEXT

Squamous cell carcinoma of the upper aerodigestive tract is a heterogenous entity. Although conventional squamous cell carcinomas are easily recognized, the morphologic variants of squamous cell carcinoma can present a diagnostic challenge. Familiarity with these variants is necessary because many are associated with unique risk factors and are characterized by specific molecular alterations (eg, nuclear protein in testis midline carcinomas). Perhaps the most important distinction is in identifying viral-related from nonviral-related carcinomas. The accurate diagnosis of these variants is necessary for prognostic and therapeutic reasons.

OBJECTIVES

To provide a clinicopathologic overview and summary of the molecular alterations of the common squamous cell carcinoma variants, including verrucous, spindle cell, acantholytic, adenosquamous, basaloid, and papillary squamous cell carcinoma, as well as nuclear protein in testis midline carcinoma, and to discuss the distinguishing features of human papillomavirus- and Epstein-Barr virus-related squamous cell carcinomas.

DATA SOURCES

Published peer-reviewed literature.

CONCLUSIONS

Familiarity with squamous cell carcinoma variants is essential for proper diagnosis and to guide appropriate clinical management. Further insight into the molecular alterations underlying those variants may lead to alterations in existing treatment approaches and to evolution of novel treatment modalities.

Clinical impact of tumor-infiltrating inflammatory cells in primary small cell esophageal carcinoma

Primary small cell esophageal carcinoma is a rare and aggressive type of gastrointestinal cancer with poor prognosis. In the present study, the impact of tumour infiltrating inflammatory cells on clinico-pathological characteristics and the patients' prognosis were analysed. A total of 36 small cell esophageal carcinomas, 19 adjacent normal tissues and 16 esophageal squamous cell carcinoma samples were collected. Qualified pathologists examined eosinophils, neutrophils, lymphocytes and macrophages on histochemical slides. The infiltration of eosinophils and macrophages in small cell esophageal carcinoma was significantly increased as compared with tumor adjacent normal tissues, and was significantly less in esophageal squamous cell carcinoma. Macrophage count was significantly associated with (p = 0.015) lymph node-stage in small cell esophageal carcinoma. When we grouped patients into two groups by counts of infiltrated inflammatory cells, Kaplan-Meier analysis revealed that high macrophage infiltration group (p = 0.004) and high eosinophil infiltration group (p = 0.027) had significantly enhanced survival. In addition, multivariate analysis unveiled that eosinophil count (p = 0.002) and chemotherapy (Yes vs. No, p = 0.001) were independent prognostic indicators. Taken together, infiltration of macrophages and eosinophils into the solid tumor appear to be important in the progression of small cell esophageal carcinoma and patients' prognosis.

The impact of the immune system on tumor: angiogenesis and vascular remodeling

Angiogenesis, the formation of new blood vessels, as well as inflammation with massive infiltration of leukocytes are hallmarks of various tumor entities. Various epidemiological, clinical, and experimental studies have not only demonstrated a link between chronic inflammation and cancer onset but also shown that immune cells from the bone marrow such as tumor-infiltrating macrophages significantly influence tumor progression. Tumor angiogenesis is critical for tumor development as tumors have to establish a blood supply in order to progress. Although tumor cells were first believed to fuel tumor angiogenesis, numerous studies have shown that the tumor microenvironment and infiltrating immune cell subsets are important for regulating the process of tumor angiogenesis. These infiltrates involve the adaptive immune system including several types of lymphocytes as well as cells of the innate immunity such as macrophages, neutrophils, eosinophils, mast cells, dendritic cells, and natural killer cells. Besides their known immune function, these cells are now recognized for their crucial role in regulating the formation and the remodeling of blood vessels in the tumor. In this review, we will discuss for each cell type the mechanisms that regulate the vascular phenotype and its impact on tumor growth and metastasis.

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.

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.

Identification of innate IL-5-producing cells and their role in lung eosinophil regulation and antitumor immunity

IL-5 is involved in a number of immune responses such as helminth infection and allergy. IL-5 also plays roles in innate immunity by maintaining B-1 B cells and mucosal IgA production. However, the identity of IL-5-producing cells has not been unambiguously characterized. In this report, we describe the generation of an IL-5 reporter mouse and identify IL-5-producing non-T lymphoid cells that reside in the intestine, peritoneal cavity, and lungs in naive mice. They share many characteristics with natural helper cells, nuocytes, and Ih2 cells, including surface Ags and responsiveness to cytokines. However, these phenotypes do not completely overlap with any particular one of these cell types. Innate non-T IL-5-producing cells localized most abundantly in the lung and proliferated and upregulated IL-5 production in response to IL-25 and IL-33. IL-33 was more effective than IL-25. These cells contribute to maintaining sufficient numbers of lung eosinophils and are important for eosinophil recruitment mediated by IL-25 and IL-33. Given that eosinophils are shown to possess antitumor activity, we studied lung tumor metastasis and showed that innate IL-5-producing cells were increased in response to tumor invasion, and their regulation of eosinophils is critical to suppress tumor metastasis. Genetic blockade or neutralization of IL-5 impaired eosinophil recruitment into the lung and resulted in increased tumor metastasis. Conversely, exogenous IL-5 treatment resulted in suppressed tumor metastasis and augmented eosinophil infiltration. These newly identified innate IL-5-producing cells thus play a role in tumor surveillance through lung eosinophils and may contribute to development of novel immunotherapies for cancer.

Pathobiology of selected tumors of the base of the skull

Skull base surgery is a new subspeciality, and, up to this point, most articles on this subject have focused on innovative operative-reconstructive approaches to tumors in this region. It is now important that we embark on a new era, the era of tumor biology, and concentrate on new ways of evaluating these neoplasms from a pathologic viewpoint. The hematoxylin-cosin section is no longer an end point, but just a beginning. This is the age of molecular biology. It is important that these tumors be evaluated, either prospectively or retrospectively, employing immunohistochemical staining, flow cytometry, oncogene expression, cytogenetics, or other techniques in order to identify important prognostic features. Data from these additional studies may then be used to develop new treatment strategies. Skull base societies should develop protocols for one or more of these tumors to ensure that they are indeed evaluated uniformly. In this article I emphasize the importance of accurate histologic classification or subclassification of these neoplasms and focus on contemporary parameters that may or may not impact on prognosis.

Myeloid cells in the tumor microenvironment: modulation of tumor angiogenesis and tumor inflammation

Myeloid cells are a heterogeneous population of bone marrow-derived cells that play a critical role during growth and metastasis of malignant tumors. Tumors exhibit significant myeloid cell infiltrates, which are actively recruited to the tumor microenvironment. Myeloid cells promote tumor growth by stimulating tumor angiogenesis, suppressing tumor immunity, and promoting metastasis to distinct sites. In this review, we discuss the role of myeloid cells in promoting tumor angiogenesis. Furthermore, we describe a subset of myeloid cells with immunosuppressive activity (known as myeloid-derived suppressor cells). Finally, we will comment on the mechanisms regulating myeloid cell recruitment to the tumor microenvironment and on the potential of myeloid cells as new targets for cancer therapy.

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.

The role of myeloid cells in the promotion of tumour angiogenesis

The use of various transgenic mouse models and analysis of human tumour biopsies has shown that bone marrow-derived myeloid cells, such as macrophages, neutrophils, eosinophils, mast cells and dendritic cells, have an important role in regulating the formation and maintenance of blood vessels in tumours. In this Review the evidence for each of these cell types driving tumour angiogenesis is outlined, along with the mechanisms regulating their recruitment and activation by the tumour microenvironment. We also discuss the therapeutic implications of recent findings that specific myeloid cell populations modulate the responses of tumours to agents such as chemotherapy and some anti-angiogenic therapies.

Eosinophilic granulocytes and damage-associated molecular pattern molecules (DAMPs): role in the inflammatory response within tumors

The development of a tumor over many years typically leads to reciprocal alternations in the host and the tumor, enabling tumor growth paradoxically in the setting of substantial necrosis and inflammation. When evaluating a tumor, it is important to assess 3 elements: (1) the quantity and quality of tumor-associated leukocytes, (2) their state of activation, and (3) tumor microenvironment. Peripheral blood eosinophilia and tumor-associated tissue eosinophilia are frequently associated with some tumor types and also found after immunotherapy with IL-2, IL-4, granulocyte-macrophage colony-stimulating factor, and antibody to CTLA-4. Within several tumor types including gastrointestinal tumors, tumor-associated tissue eosinophilia is associated with a significantly better prognosis. The converse is true in other tumor types such as differentiated oral squamous cell carcinoma. On the basis of the emergent data, tumor-associated eosinophils have at least 2 dominant nonoverlapping activities: (1) destructive effector functions potentially limiting tumor growth as well as causing recruitment and activation of other leukocytes, (2) immunoregulative and remodeling activities which suppress immune response and promote tumor proliferation. The mechanism by which eosinophils in particular are recruited into tumor tissue is largely unknown. Candidates for causing eosinophil chemotaxis into tumor tissue are the released damage-associated molecular pattern molecules (DAMPs) including the nuclear protein high mobility group box 1. High mobility group box 1 is released upon necrotic cell death and secreted by many cells, particularly during periods of nutrient, hypoxic, or oxidant stress. This overview on eosinophil biology in the context of cancer and necrosis, introduces intriguing and novel strategies targeting eosinophils to enable more effective biologic therapy for cancer patients.

Primary squamous cell carcinoma of the thyroid arising in Hashimoto's thyroiditis in an adolescent

Squamous cell carcinoma is a rare thyroid neoplasm that has been described exclusively in adults. We report what appears to be the first example of a primary squamous cell carcinoma of the thyroid gland arising in a background of Hashimoto's thyroiditis in an adolescent female. The tumor was well demarcated, confined to the right thyroid lobe, and did not metastasize, although follow up has been limited. The squamous cell carcinoma was well to moderately differentiated, and the stroma contained an abundant inflammatory infiltrate rich in lymphocytes and eosinophils. The lack of goblet cells, extracellular mucin, and extensive stromal sclerosis excluded the diagnosis of sclerosing mucoepidermoid carcinoma with eosinophilia. Immunohistochemical staining revealed focal expression of cytokeratin 7 and diffuse labeling with cytokeratin AE1/AE3. The squamous cell carcinoma overexpressed p53 protein and showed increased proliferative activity, as evidenced by the high MIB-1 labeling index. In contrast, the tumor did not show immunoreactivity for thyroglobulin or thyroid transcription factor 1.

Tissue Eosinophilic Infiltration

The assessment of stromal invasion in aerodigestive neoplastic squamous proliferation often poses diagnostic and therapeutic challenges. Eosinophilic infiltration is thought to be an adjunctive histologic criterion in determining tumor aggressiveness and invasion. We investigated whether an eosinophilic infiltration in head and neck squamous cell carcinoma measured in biopsies would aid in predicting tumor invasion, response to treatment, locoregional recurrence, and survival.

METHODS

Eighty-seven patients with in situ and invasive squamous cell carcinoma of the head and neck region were evaluated and treated according to their staging. The number of eosinophils per high-power field (eosinophil/HPF), and per 10 high-power fields (eosinophil/10 HPF) at the tumor interface and in tumor tissue, was counted and classified as focally or diffusely present. Each sample was assigned an eosinophilic index of 1-4 based on the number of eosinophils/HPF or 10 HPF. Of 87 patients, 20 patients were followed up after appropriate treatment for locoregional recurrence, distant metastasis, and disease-free survival.

RESULTS

Eosinophilic counts were elevated focally and/or diffusely more frequently in invasive squamous cell carcinoma than in noninvasive tumors. The increased eosinophilic counts, specifically > 10/HPF and > 20/10 HPF, were both significantly associated with stromal invasion. Greater than 10 eosinophils/HPF and/or > 20 eosinophils/10 HPF had the highest predictive power for invasion, with sensitivity, specificity, and positive predictive values of 66%, 94%, 96% and 61%, 100%, and 100%, respectively. Eosinophilic counts greater than 20 eosinophils/10 HPF and eosinophilic indices > 2 were virtually diagnostic for tumor invasion. Patients' biopsies with eosinophilic indices < 2 had a better survival (P = 0.0156). Using Cox regression analysis, we found that most patients' biopsies that had eosinophilic indices > 2 recurred locally or regionally.

CONCLUSIONS

The elevated eosinophilic counts in biopsies and eosinophilic indices in specimens of squamous cell carcinoma of the aerodigestive tract are a histopathologic marker associated with tumor invasion and a clinical predictor for aggressive tumor biology. Similarly, the presence of eosinophils meeting these thresholds in an excisional specimen should indicate the need for additional therapeutic measures and close surveillance to detect earlier locoregional recurrence and possible distant metastasis.

Fine-needle aspiration cytology of metastatic nasopharyngeal carcinoma

Cytological features of nasopharyngeal carcinoma (NPC) were reviewed in an attempt to select cytological criteria that permit a specific recognition of metastases. For this purpose, 54 fine-needle aspiration (FNA) procedures from 43 patients with NPC were analyzed. Thirty-two (59.3%) procedures were performed before the histological diagnosis. In 25 (46.3%) procedures, smears showed many neoplastic single cells, clusters, and abundant lymphoid cells (mixed pattern). A dissociated (single cell) pattern consisting of individual neoplastic and lymphoid cells was seen in 18 (33.3%) cases. Finally, 11 (20.4%) cases showed cohesive epithelial clusters (cohesive pattern) without relevant cellular dissociation or lymphoid cells. Squamous-cell differentiation was seen in three of these cases. Most single neoplastic cells presented as large, pleomorphic naked nuclei. Other interesting findings were granulomas (n = 3), prominent eosinophilic infiltrates (n = 4), and suppurative changes (n = 5). In most smears with mixed and dissociated patterns, a nasopharyngeal origin could be suggested. On the contrary, those smears with a cohesive pattern were indistinguishable from other head and neck carcinomas. The presence (on cervical lymph nodes) of a dissociated or mixed (single cells and groups) architectural pattern of large, anaplastic cells and naked nuclei accompanied by an abundant lymphoid component is highly suggestive of undifferentiated NPC. Cytology offers a rapid diagnosis, establishes the necessity of a complete cavum examination, and helps in avoiding unnecessary and harmful biopsies.

Tissue eosinophilia: a morphologic marker for assessing stromal invasion in laryngeal squamous neoplasms

Background

The assessment of tumor invasion of underlying benign stroma in neoplastic squamous proliferation of the larynx may pose a diagnostic challenge, particularly in small biopsy specimens that are frequently tangentially sectioned. We studied whether thresholds of an eosinophilic response to laryngeal squamous neoplasms provides an adjunctive histologic criterion for determining the presence of invasion.

Methods

Eighty-seven(n = 87) cases of invasive squamous cell carcinoma and preinvasive squamous neoplasia were evaluated. In each case, the number of eosinophils per high power field(eosinophils/hpf), and per 10 hpf in the tissue adjacent to the neoplastic epithelium, were counted and tabulated. For statistical purposes, the elevated eosinophils were defined and categorized as: focally and moderately elevated (5–9 eos/hpf), focally and markedly increased(>10/hpf), diffusely and moderately elevated(5–19 eos/10hpf), and diffusely and markedly increased (>20/10hpf).

Results

In the invasive carcinoma, eosinophil counts were elevated focally and /or diffusely, more frequently seen than in non-invasive neoplastic lesions. The increased eosinophil counts, specifically >10hpf, and >20/10hpf, were all statistically significantly associated with stromal invasion. Greater than 10 eosinophils/hpf and/or >20 eosinophils/10hpf had highest predictive power, with a sensitivity, specificity and positive predictive value of 82%, 93%, 96% and 80%, 100% and 100%, respectively. Virtually, greater than 20 eosinophils/10 hpf was diagnostic for tumor invasion in our series.

Conclusion

Our study suggests for the first time that the elevated eosinophil count in squamous neoplasia of the larynx is a morphologic feature associated with tumor invasion. When the number of infiltrating eosinophils exceeds 10/hpf and or >20/10 hpf in a laryngeal biopsy with squamous neoplasia, it represents an indicator for the possibility of tumor invasion. Similarly, the presence of eosinophils meeting these thresholds in an excisional specimen should prompt a thorough evaluation for invasiveness, when evidence of invasion is absent, or when invasion is suspected by conventional criteria in the initial sections.

Tumour-associated tissue eosinophilia as a prognostic factor in oral squamous cell carcinomas

AIMS

Tumour-associated tissue eosinophilia has been described in many sites, including head and neck. The mechanism of eosinophil recruitment and its role in tumours has not yet been defined, and its presence has been related to a favourable as well as unfavourable prognosis. The aim of this study was to evaluate the influence of tumour-associated tissue eosinophilia on the prognosis of 125 oral squamous cell carcinoma patients.

METHODS AND RESULTS

The number of eosinophils was obtained by morphometric analysis and ranged from 0 to 392 per mm2. Tumour-associated tissue eosinophilia was classified according to intensity as mild, moderate, or intense and correlated statistically to the intensity of the mononuclear inflammatory infiltrate as well as to the location of the eosinophilic inflammatory infiltrate. The multivariate analysis demonstrated that intense tumour-associated tissue eosinophilia is an independent favourable prognostic factor for oral squamous cell carcinomas.

CONCLUSION

These findings suggest an anti-tumoral role of eosinophils not as yet well understood that should be better investigated.

Significance of epidermal growth factor receptor and tumor associated tissue eosinophilia in the prognosis of patients with nasopharyngeal carcinoma

OBJECTIVE

The expression of epidermal growth factor receptor (EGFR) is one of the indicators, which can predict the malignant potential of squamous cell carcinoma of the head and neck (HNSCC). On the other hand, previous histological studies have proved tumor-associated tissue eosinophilia (TATE) to be a favorable prognostic indicator for HNSCC. We studied the prognostic significance of co-expression of EGFR and TATE.

METHODS

We examined the expression of EGFR and TATE in 53 patients with nasopharyngeal carcinoma (NPC). Biopsy specimens were subjected to immunohistochemical-staining for EGFR expression and Luna-staining for TATE. EGFR staining was considered negative when immuno-stained cells were less than 25% in a field. TATE was divided into four grades as grade 0 for 0-2 eosinophils in a high power field, grade 1 for 3-9, grade 2 for 10-29, and grade 3 for 30 or more.

RESULTS

In terms of TATE expression, 27 patients were classified as grade 0, 12 as grade 1, six as grade 2, and eight as grade 3. Forty-four patients were EGFR positive and nine were negative. We found no statistical significance in the distribution of EGFR positivity and TATE grades. Among EGFR-positive patients, 5 year survival rates were significantly better in TATE-positive (grades 1, 2, 3) patients than in TATE-negative (grade 0) patients (P=0.0139).

CONCLUSION

Eosinophils may be activated in the tumor tissue, in which the expression of EGFR is up-regulated. This suggests that the activated eosinophils in EGFR-positive tumors resulted in better prognoses. TATE infiltration and EGFR expression may be closely related to the malignant potential of NPC, and co-expression of TATE and EGFR may be an important prognostic factor.

Stromal eosinophilia in colonic epithelial neoplasms

OBJECTIVE

The purpose of this retrospective study was to determine the frequency and intensity of eosinophilic infiltration (or tissue eosinophilia) in the stroma of colonic adenomas, hyperplastic polyps, and colorectal adenocarcinomas. Eosinophilic infiltration in various malignancies has been reported but has not been evaluated in benign colorectal adenomas and hyperplastic polyps.

METHODS

We analyzed 488 colonic neoplasms: 176 tubular adenomas, 55 tubulovillous adenomas, 82 villous adenomas, 15 early carcinomas in polyps, 95 invasive adenocarcinomas, and 65 hyperplastic polyps for the presence of eosinophilic infiltration. The eosinophilic infiltration was graded as negative (< or =5%), mild to moderate (>5-40%), or marked (>40%), depending on the percentage of eosinophils relative to total inflammatory cells in the stroma.

RESULTS

Mild to moderate eosinophilia was noted in 75% of all adenomas. The transitional zone in all cases of invasive adenocarcinoma (zone between normal tissue and adenocarcinoma) revealed a high percentage of tissue eosinophilia. There was a striking absence of TE in the stroma of invasive adenocarcinomas. Only 5% of hyperplastic polyps had any eosinophilic infiltration.

CONCLUSIONS

These data suggest that, in the spectrum of colonic neoplasms, stromal eosinophilia is most prominent in adenomas and seems to decrease with progression through the adenoma-carcinoma sequence. The ramifications of this study may alter management plans and provide some prognostic information for clinical evaluation.

Prevalence and prognostic significance of tumor-associated tissue eosinophilia in nasopharyngeal carcinoma

BACKGROUND

Tumor-associated tissue eosinophilia (TATE) has been associated with an improved prognosis in a variety of neoplasms.

METHODS

Diagnostic biopsy specimens from 96 patients with nasopharyngeal carcinoma (NPC) were reviewed for the presence of TATE by an observer blinded to the patients' clinical histories. Comparisons between patients with and without TATE with respect to the probabilities of local recurrence, distant metastasis, and survival were performed using the log rank test on Kaplan-Meier product-limit estimates and the Cox proportional hazards model.

RESULTS

The prevalence of TATE in these patients was 32%, and was not significantly associated with local recurrence, distant metastasis, or survival.

CONCLUSIONS

These results are discordant with those of studies in other tumor models, although comparison is hampered by varying definitions of TATE. The differing results may be due to variations in the degree of activation of the eosinophils present in TATE in different tumors.

Eosinophilic infiltration in advanced laryngeal squamous cell carcinoma. Veterans Administration Laryngeal Cooperative Study Group

Tumor-associated tissue eosinophilia (TATE) has been related to prognosis in epithelial cancers, including cancers at several head and neck sites. This study prospectively examined 248 patients with stage III and IV laryngeal squamous cell carcinoma to determine prevalence and potential prognostic significance of TATE. Pretreatment tumor specimens were histopathologically evaluated. Presence and degree of TATE were analyzed with regard to other tumor characteristics, patient characteristics, and outcome criteria. Median follow-up was 48 months. Eosinophilia was found in 22.5% of specimens and was not related to tumor site, stage, patient age or sex, or treatment modality. Overall and disease-free survival rates and response to induction chemotherapy did not differ significantly with respect to TATE. This study represents the first long-term, prospective evaluation of TATE and its prognostic significance in a single head and neck site. Contrary to the findings of earlier preliminary reports, our results suggest that TATE is not a clinical useful prognostic parameter in advanced laryngeal squamous cell carcinoma.

Tumor-associated tissue inflammatory reaction and eosinophilia in primary superficial bladder cancer

In a retrospective study the data of 428 patients with primary superficial transitional cell carcinoma of the bladder were evaluated. The histologic slides were reviewed for presence of a tumor-associated tissue inflammatory reaction, especially tumor-associated eosinophilia. Tumor-associated cell infiltration was found in 23.1 percent and tumor-associated eosinophilia in 2.1 percent. Tumor-associated cell infiltration was associated with less recurrences (p = 0.01). Tumor progression rate was not significantly influenced by tumor-associated cell infiltration. Tumor-related death rate was lower in the group with tumor-associated cell infiltrate (p = 0.50). Using the Cox regression model carcinoma in situ of the tumor margin, tumor-associated cell infiltrate, and grade of differentiation appeared to be important factors in the prognosis for survival.

Local and systemic eosinophilia in patients with carcinoma of the uterine cervix undergoing radiation therapy: correlation with radiation response

Forty-nine patients with squamous carcinoma of the uterine cervix undergoing supervoltage 60Co radiotherapy were investigated to determine the significance of quantitation of eosinophils in the tumour tissue as well as in blood. The blood absolute eosinophil count (AEC) at presentation was higher in patients with Stages III and IV disease (0.52 +/- 0.09 x 10(9)/l, mean +/- SEM) when compared with early stages (Stages I and II, 0.35 +/- 0.07 x 10(9)/l). Forty-four patients (90%) showed a steady rise in AEC during the course of therapy. The patients showing good radiation response (n = 13, greater than or equal to 50% regression), displayed a more pronounced rise in AEC during the course of radiotherapy (0.66 +/- 0.24 x 10(9)/l) and had more eosinophils in the tumour tissue (7.4 +/- 0.66/oil immersion field) than the poor responders (n = 36, less than 50% regression, rise in eosinophil count 0.22 +/- 0.04 x 10(9)/l, eosinophils in tumour tissue 2.9 +/- 0.55/oil emersion field, P less than 0.0001 for both parameters). We conclude that quantitation of eosinophils in blood and tumour tissue before and during radiotherapy in patients with squamous carcinoma of the uterine cervix is useful in predicting radiation response.

Pelvic lymph node metastases in early invasive carcinoma of the cervix--histopathological 'risk' factors

Histopathological features in 89 cases of Stage 1B and early 2A invasive carcinoma of the cervix who underwent Wertheim radical hysterectomy and pelvic lymphadenectomy were studied. Depth of tumour invasion and lymphatic/vascular space permeation by tumour cells were significantly associated with lymph node metastases. The other features such as tumour type, and stromal leucocytic reaction showed no significant relationship to the presence of lymph node metastases.

DNA content in nasopharyngeal carcinoma

DNA analysis by flow cytometry was performed on tissue blocks from 41 patients with nasopharyngeal carcinoma. The histologic slides were reviewed by a pathologist and blindly classified according to the World Health Organization classification. The paraffin-embedded blocks were processed to obtain individual nuclei, which were then stained with propidium iodide. The nuclei were analyzed on a flow cytometer. Excluding 10 uninterpretable histograms, the remainder were interpreted blindly and classified as diploid or aneuploid. The Cox proportional hazards survival model was used to analyze stage, histology, radiation dose, and ploidy. We observed more diploids (23 of 31; 74%) than aneuploids (eight of 31; 26%). The 2-year survival rate of diploids was 55%, compared with 25% of aneuploids (P less than .05). We conclude that ploidy status is an independent prognostic factor in nasopharyngeal carcinoma.

Eosinophilic ulcer

A 10-year review of biopsy accessions revealed 15 cases of eosinophilic ulcer. Six manifested recurrent or multiple lesions, and two exhibited histologic atypia. The possible relationships to other oral and systemic diseases are discussed.