The role of M1 (CD11c) and M2 (CD163) interplay in the pathogenesis of oral submucous fibrosis and its malignant transformation: An immunohistochemical analysis.

OBJECTIVES: The M1/M2 macrophage framework is crucial in organ fibrosis and its progression to malignancy. This study investigated the possible role of M1/M2 macrophage interplay in the pathogenesis of oral submucous fibrosis (OSF) and its malignant transformation by analysing immunohistochemical expression of CD11c (M1) and CD163 (M2) markers. METHODS: Immunohistochemistry was performed using primary antibodies against CD11c and CD163 on ten formalin-fixed paraffin-embedded tissue blocks for each group: (i) Stage 1 OSF, (ii) Stage 2 OSF, (iii) Stage 3 OSF, (iv) Stage 4 OSF, (v) well-differentiated squamous cell carcinoma (WDSCC) with OSF, and (vi) WDSCC without OSF. Ten cases of healthy buccal mucosa (NOM) served as controls. RESULTS: Epithelial quick scores of M1 (CD11c) in NOM, Stages 1-4 OSF, and WDSCC with and without OSF were 0, 1.8, 2.9, 0.4, 0, 0, and 0, while connective tissue scores were 0, 3.2, 4.3, 2.7, 0.5, 1.2, and 2.4, respectively. Epithelial scores for M2 (CD163) were 0, 0.8, 0.8, 2.1, 0.6, 0.8, and 0.2, and connective tissue scores were 0, 1.8, 2.6, 3.9, 2.2, 5, and 4.4, respectively. Stages 3 and 4 OSF, WDSCC with and without OSF exhibited higher M2/M1 ratios compared to NOM and Stages 1-2 OSF. CONCLUSION: The interaction between M1 (CD11c) and M2 (CD163) macrophages, leading to M2 polarisation, plays a crucial role in the pathogenesis of OSF and its potential malignant transformation.

Persistent Buccopharyngeal Membrane - A Systematic Review of Case Reports and Case Series.

OBJECTIVE: Persistent buccopharyngeal membrane (PBM) is a rare anomaly associated with failure of ecto-endodermal resorption of the buccopharyngeal membrane on the 26th day of intrauterine life. The current literature has insufficient information about PBM. DESIGN: Systematic Review. PATIENTS, PARTICIPANTS: Online electronic databases such as PubMed-MEDLINE, Embase, and Scopus were searched using appropriate keywords from the earliest available data until 30th August 2022, with no language restriction. Additional sources such as Google Scholar, major journals, gray literature, conference proceedings, and cross-referencing were also explored. MAIN OUTCOME MEASURES: The present systematic review evaluated and analysed the data available on PBM along with its treatment options and clinicopathological findings, prevalence, and prognosis of the patient. RESULTS: Thirty-four publications with 37 reported cases were included in this systematic review. The majority of patients had dyspnea (n = 18), followed by dysphagia (n = 10). Approximately 16 patients suffering from PBM reported orofacial abnormalities. Seventeen patients reported complete PBM, and 18 patients had partial PBM. The treatment modality followed by most patients (n = 15) was surgical excision of the membrane, along with stent placement in four patients. Oropharyngeal reconstruction was performed in four cases. The overall prognosis and survival rate of this rare condition is good. CONCLUSION: This review suggests that PBM is poorly understood, and the diagnosis of partial PBM is confirmed only when the patient complains of difficulty in breathing or eating. In-depth analysis and follow-up of the reported cases should be performed to diagnose the disease early so that clinicians can provide adequate treatment to the patients.