Clinicopathological and immunohistochemical analysis of plasma cell gingivitis- A retrospective study.

Background: This study aims to describe the demographics and clinicopathological characteristics of the cases of plasma cell gingivitis (PCG) reported in our institute, supported by a review of pertinent literature. Further, we investigated the role of the cluster of differentiation CD138, Ki67, CD56, and CD117 immunoexpression in the differential diagnosis of PCG from plasma cell dyscrasias. Materials and Methods: All histopathologically confirmed cases of PCG, whose relevant details could be obtained, were included in this study. They were subjected to panel of immunohistochemical markers to exclude plasma cell malignancies. Further, published English literature for PCG since 1970-2020 was reviewed. Results: Nine histopathologically confirmed cases of PCG, were retrieved from the archives of our department. The cases comprised 3 males and 6 females with their ages ranging between 14 and 82 years. The plasma cells exhibited equivocal reactivity for kappa and lambda; and immunonegativity for CD56, CD117 with low Ki67 proliferation index. Published literature in English showed 43 cases of PCG were predominantly female; the diffuse involvement of maxilla and mandible was a common finding. Conclusion: In addition to kappa lambda reactivity, an immunoprofile of CD138, Ki67, CD56, and CD117 may be used as a diagnostic adjunct to exclude malignant plasma cell lesions in confusing cases.

Distribution of biopsied gingival lesions according to the proceedings from the 2017 World Workshop classification: A three-year retrospective study.

BACKGROUND: The gingiva is a common site for neoplastic or non-neoplastic lesions. Neoplasms refer to progressive autonomous growth that can have either a benign or a malignant course. On the other hand, non-neoplastic lesions are mainly inflammatory, or occur as a reaction to some kind of irritation or lowgrade injury. OBJECTIVES: Assessing the frequency distribution of gingival lesions is important to optimize oral health care services. The present study retrospectively analyzed the frequency distribution of gingival lesions on the basis of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. The secondary objective was to compare this system with the 1999 International Workshop classification system. MATERIAL AND METHODS: The hematoxylin and eosin (H&E)-stained histopathological slides of the gingival lesions reported over the last 3 years (2018-2020) were retrieved from the archive of the Division of Oral Pathology and Microbiology at a tertiary care hospital in New Delhi, India. Correlating clinical, radiological and pathological details enabled the categorization of lesions according to the new classification system. RESULTS: In total, 73 gingival lesions were analyzed. Among these, reactive processes were the most frequent (39.73%), followed by inflammatory and immune conditions and lesions (26.03%), malignant tumors (21.92%), benign epithelial lesions (5.48%), and oral potentially malignant disorders (OPMDs) (5.48%). Genetic/developmental disorders were the least frequent (1.37%). However, as per the 1999 American Academy of Periodontology (AAP) system, the majority of lesions belonged to a non-specified category. CONCLUSIONS: The frequency distribution of biopsied gingival lesions according to the 2017 World Workshop classification in comparison with the previous classification system showed that differences between the 2 systems could be attributed to heterogeneous terminology rather than to real geographical variations.

Role of MDM2, CDK4, BCL2, Parafibromin and Galectin 1 in Differentiating Osteosarcoma from its Benign Fibro-osseous Lesions.

Benign fibro-osseous lesions (BFOLs) are a diverse group of lesions showing considerable degree of overlap with low grade osteosarcoma (LGOS). Further, de-differentiated osteosarcoma (DOS) is usually indistinguishable from conventional high-grade OS (COS) if LGOS foci are not identified. Thus, there is a need for adjunctive immunohistochemical markers to differentiate OS from benign FOLs as well as DOS from COS. This study evaluated the role of immunohistochemical expression of MDM2, CDK4, parafibromin, BCL-2 and Galectin-1 (Gal-1) in accurate characterization of benign FOLs and in differentiating them from OS. From our archives, we retrieved 101 tissue samples which were diagnosed as osteosarcoma (OS) /ossifying fibroma (OF) / fibrous dysplasia (FD) or fibrous hyperplasia (FH) and examined their immunohistochemical staining pattern with the aforementioned antibodies. MDM2 showed 100% specificity for diagnosing OS. CDK4 and Gal-1 showed linear increase in immunoexpression from benign BFOLs to OS. BCL-2 showed equivocal immunopositivity in OF and OS, but the positivity was higher than that observed in FD. The highest immunoexpression for parafibromin was seen in FD followed by OF and OS cases. Thus, MDM2 is most specific, and Gal-1 is most sensitive of all the markers studied in differentiating OS from benign mimics. Combination of these two markers can be used as an adjunct to conventional imaging and microscopy in accurate characterization of these lesions. Further MDM2 overexpression can differentiate DOS and COS.