AI-Assisted Screening of Oral Potentially Malignant Disorders Using Smartphone-Based Photographic Images.

The prevalence of oral potentially malignant disorders (OPMDs) and oral cancer is surging in low- and middle-income countries. A lack of resources for population screening in remote locations delays the detection of these lesions in the early stages and contributes to higher mortality and a poor quality of life. Digital imaging and artificial intelligence (AI) are promising tools for cancer screening. This study aimed to evaluate the utility of AI-based techniques for detecting OPMDs in the Indian population using photographic images of oral cavities captured using a smartphone. A dataset comprising 1120 suspicious and 1058 non-suspicious oral cavity photographic images taken by trained front-line healthcare workers (FHWs) was used for evaluating the performance of different deep learning models based on convolution (DenseNets) and Transformer (Swin) architectures. The best-performing model was also tested on an additional independent test set comprising 440 photographic images taken by untrained FHWs (set I). DenseNet201 and Swin Transformer (base) models show high classification performance with an F1-score of 0.84 (CI 0.79-0.89) and 0.83 (CI 0.78-0.88) on the internal test set, respectively. However, the performance of models decreases on test set I, which has considerable variation in the image quality, with the best F1-score of 0.73 (CI 0.67-0.78) obtained using DenseNet201. The proposed AI model has the potential to identify suspicious and non-suspicious oral lesions using photographic images. This simplified image-based AI solution can assist in screening, early detection, and prompt referral for OPMDs.

Roles of the matricellular protein Tenascin-C in T-lymphocyte trafficking and etiopathogenesis of Oral Lichen Planus.

OBJECTIVE: This study was aimed at examining the role of Tenascin-C in T cell trafficking in Oral Lichen Planus (OLP). DESIGN: For the in vivo immunohistochemical analyses, 115 OLP samples were collected from patients and immunostaining was performed. The intensity and distribution of TN-C expression were quantified and correlated with histological analyses of basement membrane integrity and presence of inflammatory infiltrate. For the in vitro study, TN-C and collagen were coated on culture plates and migration of T lymphocytes was assessed. RESULTS: TN-C immunoexpression was increased in terms of both distribution and intensity along the basement membrane zone. These changes were significantly associated with basement membrane duplication (distribution p < 0.002 and intensity p < 0.001) and bands of inflammation (distribution p < 0.002 and intensity p < 0.001) assessed by Chi-square test. T lymphocytes demonstrated significant migration towards TN-C as compared to collagen (n = 3, p < 0.05). CONCLUSIONS: These findings indicate TN-C may have a key role in promoting T cell migration at the epithelial-mesenchymal junction in OLP. These observations suggest TN-C could be a good target for therapeutic intervention, either in itself or synergistically with anti-inflammatory directed strategies in this chronic disease management.

Role of immunoreactive patterns of lymph nodes in neck dissection cases of oral squamous cell carcinoma: a clinical and histopathological study.

OBJECTIVES: Metastasis in oral squamous cell carcinoma (OSCC) can occur in a variety of ways, and draining lymphatics and lymph nodes serve as a common route. Prior to metastasis, lymph nodes elicit an immune response to either wall off or create a favorable environment for homing of tumor cells. This immune response to tumor stimuli is visualized by recognizing various immunoreactive patterns exhibited by the lymph node. The present study aims to evaluate the role of immuno-morphologic patterns of the lymph node in neck dissection for cases of OSCC. MATERIALS AND METHODS: Our retrospective study included 50 neck dissection cases of OSCC and a total of 1,078 lymph nodes. The grades of primary tumors with eight different immunoreactive patterns were compared. Vascularity and metastasis in lymph nodes were also evaluated. RESULTS: The lymphocyte predominant pattern was the most common immunoreactive pattern found in 396 of 1,078 lymph nodes. Patterns of lymphocyte predominant (P=0.0005), sinus histiocytosis (P=0.0500), paracortical hyperplasia (P=0.0001), cortical hyperplasia (P=0.0001), and increased vascularity (P=0.0190) were significantly associated with tumor grade. CONCLUSION: The present study adds to the understanding of lymph node immunoreactivity patterns and their correlation with tumor grade. We recommend further study of lymph node patterns for all sentinel lymph node biopsies and routine neck dissections for OSCCs.

Assessment of cell block technique in head and neck pathology diagnoses: A preliminary study.

OBJECTIVE: The head and neck region is a composite site made of multiple tissue components. These tissues when affected by disease or pathology present with an array of changes in the tissue architecture and pattern. It is essential to visualize the cellular details and tissue patterns for accurate diagnosis and treatment planning. Aspiration cytology primarily makes use of the cellular details for diagnosing lesions of the head and neck. Despite the promising results, its use is still limited in certain cases of the head and neck. The reason implicated could be the indiscernible appearance of cells in the absence of tissue integrity. In this regard, cell blocks are known to facilitate the visualization of the cytomorphological as well as the tissue arrangement patterns. Thus, the present study was designed to evaluate the role of cell block cytology in the diagnosis of various lesions of the head and neck. METHODS: Odontogenic lesions, epithelial carcinomas and connective tissue pathology of the head and neck origin were included in the study (n = 45). Aspiration cytology smears and cell block diagnosis were compared with tissue biopsy diagnosis for determining their sensitivity (%) and diagnostic efficacy. RESULTS: Cell blocks showed distinct preservation of the architectural pattern. In case of fluid-filled lesions, the contents were preserved and correlated with the tissue biopsy results. The results of cell blocks were similar to that of tissue biopsy in majority of the cases (95.56%). CONCLUSION: We recommend using cell blocks as a part of routine laboratory practice for all head-neck cases.

Modified Alcohol-Formalin Cell Block Technique in Head and Neck Pathology Diagnosis.

OBJECTIVES: Cell block preparation is a recognized technique in histopathological diagnosis. This technique aids in maintaining an intact architecture and reducing the diagnostic errors associated with fine-needle aspiration cytology. Numerous techniques have been put forth, but the need for an optimal technique for routine use in the laboratory still persists. The aim of our study was to establish a cell block technique which aids in the accurate diagnosis of head and neck pathology. METHODOLOGY: A modified cell block technique was developed using alcohol-formalin as a fixative. Forty fine-needle aspiration fluids from clinically and radiologically diagnosed cases of head and neck pathology were used as samples. The cell block sections were compared with the cytology smears to determine the utility of the technique. RESULTS: The cell blocks presented with better preservation of the architectural framework and enabled a quick diagnosis. Cellular clumping was negligible, and nuclear as well as cellular details were maintained similar to tissue sections. It led to the integration of conventional techniques using 10% neutral buffered formalin with that of the 10% alcohol-formalin technique. CONCLUSION: Modified cell block technique can be used as a simple and effective tool in the routine diagnosis of head and neck pathology.

Immunoexpression of programmed cell death 4 protein in normal oral mucosa, oral epithelial dysplasia and oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the frequently reported cancer of the head and neck. Recent studies are being conducted to evaluate the role of potential markers for diagnosing the stages of development of OSCC from normal cells. AIM: The aim of this study is to evaluate and compare the immunoexpression of programmed cell death 4 (PDCD4) protein in normal oral mucosa, oral epithelial dysplasia (OED) and OSCC. MATERIALS AND METHODS: Histologically diagnosed, formalin-fixed paraffin-embedded archived cases (n = 100) of normal mucosa (n = 10), OED (n = 60) and OSCC (n = 30) were analyzed immunohistochemically in the present retrospective study using monoclonal rabbit antihuman PDCD4. OED and squamous cell carcinoma were graded according to the World Health Organization and Broder's histological grading criteria, respectively. Clinical parameters and immunohistochemical results were analyzed by Fisher exact test using SPSS software. P <0.05 was indicative of significant differences. RESULTS: PDCD4 expression was observed in the normal oral mucosa, OED and OSCC. The maximum expression was observed in the normal oral mucosa, which reduced significantly in OED and OSCC (P = 0.017). With the increase in the transformation from normal cells to cancer cells, a shift from nuclear to cytoplasmic staining was observed indicating predominant cytoplasmic localization of stain as a feature of altered cells. CONCLUSION: The present study delineates the molecular difference between the normal, dysplastic and carcinomatous cells; and points toward the role of PDCD4 localization in the proliferation of cells. This study thus highlights the need for further research with inclusion of long follow-up period and other pathological criteria such as inflammation and microenvironment, immune status of patient and tumor stage, which could aid in the development of prospective diagnostic options.