Evaluation of Cytotoxic T Lymphocytes and Natural Killer Cell Distribution in Oral Squamous Cell Carcinoma and Oral Epithelial Dysplasia: An Immunohistochemical Study.

Background The tumor microenvironment comprises stromal cells, a few immune cells, vascular channels, and an extracellular matrix. The immune cells play a pivotal role in arresting the development of various tumors by identifying and killing the abnormal tumor cells. These immune cells with cytotoxic function include the natural killer (NK) cells and CD8+ T lymphocytes. Human NK cells express the cell surface marker CD57 and can be identified by using monoclonal antibodies. CD8+ cytotoxic T cells are a critical subpopulation of T cells and are important mediators of adaptive immunity. The anti-tumor immunity is important to assess the prognosis of tumors and develop new therapies. This study aimed to evaluate the immunohistochemical expression of CD8 and CD57 immune cells in oral squamous cell carcinoma (OSCC), oral epithelial dysplasia (OED), and normal oral mucosa. Methodology Clinically diagnosed and histopathologically confirmed cases of OSCC (n = 22), oral leukoplakia with OED (n = 22), and normal oral mucosa (n = 22) comprised the study groups. The tissue sections were subjected to immunohistochemical analysis for CD8 and CD57 expression by calculation of the mean labeling index. The results were statistically analyzed using a one-way analysis of variance, Bonferroni multiple comparison test, and Student's t-test. SPSS software version 20.0 (IBM Corp., Armonk, NY, USA) was used for the statistical analysis, and the significance level was set at 0.05. Results An overall statistically significant difference was obtained in the number of CD8+ T lymphocyte cells and CD57+ NK cells when compared between OSCC, OED, and normal oral mucosa (p = 0.01). Variations in the number of CD8+ T lymphocyte cells and CD57+ NK cells were observed when a comparison was made between OED and OSCC and between OSCC and normal mucosal samples (p = 0.01). The study results showed that the mean labeling index of CD8 and CD57 increased in OSCC when compared to OED and normal mucosa (p = 0.01). Conclusions Samples of OED with moderate or severe dysplasia and samples of OSCC were accompanied by a higher level of infiltrating immune cells such as T cells, B cells, NK cells, and macrophages when compared to normal mucosa. The results suggested that the expression of CD8 and CD57 cells increased from normal mucosa to OED and the highest expression was found in OSCC. CD8 and CD57 could be used as surrogate markers to assess the malignant potential of the lesion and to determine the prognosis of patients with oral cancer.

Correlation of PD-1 and PD-L1 expression in oral leukoplakia and oral squamous cell carcinoma: an immunohistochemical study.

The programmed cell death protein (PD-1)/programmed cell death protein ligand (PD-L1) pathway and cytotoxic T lymphocyte antigen are the most important co-stimulatory molecules that play a key role in the negative regulation of T cells during carcinogenesis. We aimed to evaluate the immunohistochemical expression of PD-1 and PD-L1 in oral leukoplakia and squamous cell carcinoma compared with normal oral mucosa. Twenty-five cases of oral squamous cell carcinoma, oral leukoplakia and normal oral mucosa tissue specimens were immunohistochemically stained to assess PD-1 and PD-L1 expression. The PD-L1 positivity of subepithelial TAFs (p < 0.001) increased with increasing grades of oral leukoplakia. Pearson's correlation indicated a high positive correlation between the PD-L1 labelling index of epithelial tumour cells and the PD-1 labelling index of tumour infiltrating lymphocytes (p value: 0.005) in OSCC. A high positive correlation was noted between the H-score of PD-L1 positive tumour epithelial cells and the H-score of PD-1 positive tumour infiltrating lymphocytes in OSCC (p value: 0.001). PD-L1 positivity increased in dysplastic epithelial cells from premalignant lesions to malignancy. The sub-epithelial PD-L1 positive TAFs were higher in oral leukoplakia compared to OSCC inferring that PD-L1 positivity in TAFs decreased with malignant transformation. The PD-1 positivity in TILs was higher in oral leukoplakia than in OSCC.

Epithelial-mesenchymal transition in cancer stem cells: Therapeutic implications.

Cancer stem cells (CSCs) are cancer cells that possess characteristics associated with normal stem cells, specifically the ability to give rise to all cell types found in a particular cancer sample. CSCs may generate tumors through the processes of self-renewal and differentiation into multiple cell types. CSCs present in tumors are normally resistant to conventional therapy and may contribute to tumor recurrence. Tumor residuals present after therapy, with CSCs enrichment, have all the hallmarks of epithelial-mesenchymal transition (EMT). In this review, we discuss the relationship between EMT and CSCs in cancer progression and its therapeutic implications in oral squamous cell carcinoma.

Chondrosarcoma of the maxilla in a young female: A case report.

ABSTRACT: Sarcomas of the head and neck region are rare tumors, constituting less than 1% of malignant neoplasms in this area. Approximately 20% of these sarcomas originate from bone or cartilage. Chondrosarcomas are malignant mesenchymal tumors showing cartilaginous differentiation. These tumors usually show a predilection to the male gender and occur commonly in the older age group. Here, we report a case of chondrosarcoma of the anterior maxilla in a young female.

Significance of tumour budding and invasive characteristics in grading of oral squamous cell carcinoma.

Background: Tumour budding has been recognized as a morphologic marker of tumour invasion. Invasive characteristics such as depth of invasion, mode of invasion and worst pattern of invasion are potentially powerful parameters predicting the regional metastasis. Aim: This study was done to understand the significance of tumour budding and various characteristics of invasion and their impact on grading of oral squamous cell carcinoma. Materials and Methods: An immunohistochemical study was performed on tissue sections obtained from 34 paraffin-embedded blocks of clinically and histologically diagnosed cases of oral squamous cell carcinoma. The sections were stained with pan cytokeratin and observed under high power magnification. Results: Tumour budding and the invasive patterns were found to be significant in OSCC. A proposed grading system based on tumour budding and cell nest was found to have a significant correlation with the WHO grading system. Conclusion: This study demonstrated the importance of using tumour buds as an additional parameter in the grading system and also assessed the importance of invasive patterns, cellular atypia and stromal contents in OSCC.

Immunohistochemical evaluation of galectin-3 expression in oral squamous cell carcinoma, oral leukoplakia and normal mucosa.

Background: Galectin 3 (Gal-3) has diverse functions critical in cancer biology including cell proliferation, apoptosis, evasion of immune responses and angiogenesis. The expression of Gal-3 is heterogeneous in normal and neoplastic tissues. In oral squamous cell carcinoma (OSCC) and oral leukoplakia (OL), both increased and decreased expressions of Gal-3 were elicited in numerous studies. Aims: To evaluate, compare and correlate the immunohistochemical expression of Gal-3 in OSCC, OL and normal oral mucosa. Settings and Design: The study was conducted at the Department of Oral Pathology and Microbiology at PMS College of Dental Science and Research, Vattapara, Thiruvananthapuram. This is a retrospective analytical study. Methods and Material: Clinically diagnosed and histopathologically confirmed cases of OSCC (n = 21), OL (n = 21), and normal oral mucosa (n = 21) were included in the study. Paraffin-embedded tissues were subjected to immunohistochemical analysis for Gal-3 expression. Gal-3 staining expression, staining distribution and cellular localisation were evaluated. All sampled categories were compared using immunohistochemical scoring analysis such as the H-score, labelling index (LI), immunoreactive score (IRS) and staining intensity (SI). Statistical Analysis: The results were statistically analysed using multivariate analysis of variance (MANOVA) within and among the groups. Results and Conclusion: The statistical inferences obtained found that the H-score could be used as a guideline for better differentiation between the groups and among the groups. The P value obtained was < 0.0125 and was found to be significant. The observation in our study shows that the immunohistochemical expression of Gal-3 gradually decreased from normal oral mucosa to OL to OSCC.

Expression of transmembrane protein aquaporin-3 in oral epithelial dysplasia and oral squamous cell carcinoma.

OBJECTIVES: The objective of this study was to evaluate aquaporin-3 (AQP3) expression in patient samples of oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC), thereby assessing the potential of AQP3 as a molecular marker for tumor progression. STUDY DESIGN: An in vitro comparative study was done to determine the AQP3 expression on 20 surgical biopsy specimens each of OED and OSCC using immunohistochemistry. Twenty specimens of normal oral mucosa were kept as controls. The results were statistically analyzed using one-way analysis of variance and post hoc analysis. RESULTS: The expression of AQP3 was analyzed and further semiquantified using H-scores. The mean H-score showed a statistically significant difference between OSCC, OED, and normal oral mucosa (P < .05). There was a significant increase in the expression of AQP3 in OSCC and OED compared to normal oral mucosa. The highest expression was observed in OSCC (P < .01). CONCLUSION: The observations of the study indicate that staining intensity of AQP3 increased from dysplastic noninvasive lesion to invasive OSCC, suggesting a possible role of AQP3 as a biomarker for tumor progression.

Prevalence of oral potentially malignant disorders and oral malignant lesions: A population-based study in a municipal town of southern Kerala.

Oral cancer burden poses a major challenge in India. Oral cancer in the majority of instances arises from preexisting oral potentially malignant disorders (OPMDs). Early detection of OPMD and elimination of primary risk factors such as smokeless and smoking tobacco help in reduction of oral cancer. A study was conducted to find the prevalence and associated risk factors of OPMDs and oral malignant lesions (OMLs) in Punalur township of South Kerala. A total of 2368 patients were screened, out of which 156 were identified with OPMD and 5 with OML. A male predominance was noted for both OPMD and OML. Strong association with smokeless tobacco and smoking tobacco habits was seen with patients having OPMD and OML.

An extensive swelling in the anterior mandible - A case report.

INTRODUCTION: Glandular odontogenic cyst is a rare developmental odontogenic cyst, which often pose a challenge to diagnose it clinically. PRESENTATION OF A CASE: A 32 year old female patient was referred to the oral and maxillofacial surgery department with a chief complaint of a painless swelling in the anterior mandible, extending from mandibular left premolar to right first molar region, with fluctuancy and egg shell crackling at right premolar region. The associated teeth were firm. Radio graphically a large radiolucent lesion was seen extending from mandibular left premolar to right first molar region. DISCUSSION: We had many differential diagnoses including keratocystic odontogenic tumour, ameloblastoma and radicular cyst. Incisional biopsy was taken from the most fluctuant area, which was histopathologically suggestive of glandular odontogenic cyst. Enucleation of the cyst, peripheral ostectomy, extraction of teeth and Carnoy's solution application were done under general anaesthesia. CONCLUSION: We often neglect to include uncommon lesions in the differential diagnosis, which may lead to inadequacy in the management protocol. Whenever possible, incisional biopsy should be performed to confirm the lesion before surgical enucleation. Here we present a case in which we were fortunate enough to diagnose the lesion by an incisional biopsy and managed according to the standard protocol.

Uncommon opportunistic fungal infections of oral cavity: A review.

The majority of opportunistic oral mucosal fungal infections are due to Candida albicans and Aspergillus fumigatus species. Mucor and Cryptococcus also have a major role in causing oral infections, whereas Geotrichum, Fusarium, Rhodotorula, Saccharomyces and Penicillium marneffei are uncommon pathogens in the oral cavity. The broad spectrum of clinical presentation includes pseudo-membranes, abscesses, ulcers, pustules and extensive tissue necrosis involving bone. This review discusses various uncommon opportunistic fungal infections affecting the oral cavity including their morphology, clinical features and diagnostic methods.

Clear cell myoepithelioma of palate with emphasis on clinical and histological differential diagnosis.

Myoepitheliomas account for less than 1% of all salivary gland tumors and mostly occur in the parotid gland and palate. A 58-year old male patient reported to the Outpatient Department of PMS College of Dental Science and Research (Kerala, India) with a slow growing painless swelling on the palate for 4 years. Pleomorphic adenoma, basal cell adenoma, myoepithelioma, cyst adenoma, lipoma, neurofibroma, neurilemmoma and leiomyoma were considered. Histopathology revealed a thinly encapsulated tumor composed mainly of sheets of clear cells mixed with cells having eosinophilic cytoplasm. Histopathological differential diagnosis included pleomorphic adenoma, oncocytoma, oncocytic hyperplasia, sebaceous adenoma, malignant salivary gland neoplasms and metastatic lesions from kidney and thyroid. Myoepitheliomas mostly occur in the parotid gland and palatal region and various histological types of myoepithelioma are described. Myoepitheliomas of the palate are rare with clear cell variant even rarer.

Bisphosphonate induced osteonecrosis of jaw in breast cancer patients: A systematic review.

BACKGROUND: Bisphosphonate therapy is widely used for the treatment of bone metastasis in breast cancer patients. AIM: The aim of this study is to estimate the overall prevalence of bisphosphonate induced osteonecrosis of jaw (BONJ) in breast cancer patients with bone metastasis. MATERIALS AND METHODS: A literature review was conducted to search and evaluate all the articles that contained original data on the prevalence of BONJ in breast cancer patients from the year 2003-2009. Pubmed search terms used were bisphosphonate, osteonecrosis, breast cancer and jaw. Eleven publications that fulfilled the inclusion criteria were chosen for the study. Case reports and reviews were excluded from the analysis based on assessing the title and abstract. RESULTS: Of the 2490 breast cancer patients, 69 developed BONJ with the overall prevalence rate of 2.8%. All the patients with BONJ had received zoledronate or pamidronate, either alone or in combinations. CONCLUSION: BONJ is a significant complication occurring in 2.8% of the breast cancer patients receiving bisphosphonates for metastatic bone disease. It is very important to identify the trigger factors associated with BONJ and also to establish guidelines for the prevention and effective treatment of this condition.

A rare case of dentigerous cyst in a one year old child: the earliest known reported occurrence.

Dentigerous cysts are developmental odontogenic jaw cysts, commonly manifesting in the second and third decades of life. Very few of these cysts have been reported in children younger than 10 years of age. This article describes a rare case of dentigerous cyst in a 1-year-old boy, the youngest case to be documented. The clinical, radiographic and histopathologic features are discussed; the increased possibility of occurrence of these cysts at a very young age and the importance of timely diagnosis of such cysts to avoid future complications is emphasized.