In the 2022, World Health Organisation classification of odontogenic tumours, the clear cell odontogenic carcinoma is designated as a malignant odontogenic tumour with high recurrence and aggressive behaviour. Deceptive behaviour in the context of a wide range of differentials presents a significant diagnostic problem. It is the fifth most commom type of malignant odontogenic tumor. A systematic assessment of published cases, case series, and retrospective investigations of diagnostic significance of EWSR1 gene in clear cell odontogenic carcinoma is presented to determine trends in presentation, diagnostic characteristics, treatment, and patient outcome. To locate papers reporting clear cell odontogenic carcinoma and EWSR1, extensive database searches were carried out. Demographics, tumour location, immunohistochemical and molecular tests, treatment, follow-up, and recurrence were the variables. 34 cases were detected; 52.9% (n = 18) of the cases were females. The average age was 62.5 years, with a range of 43-82 years. The average size ranged from 3.4 to 8 cm. The mandibular body was the most common location, followed by the maxilla. Maximum immunohistochemistry positivity revealed by CK 19, CKAE1/3, EMA and p63. Most common gene fusion detected was EWSR1-ATF1 in 62.4% of cases contributing to its diagnostic attributes. Surgical treatment was used in 97% of cases. The average follow-up period was 30.3 months, and recurrence was reported in 52.4% of the cases. CCOC can metastasize, and the prognosis is fair. This is first systematic review, where we have attempted to consolidate the mutational expression of EWSR1 in Clear cell odontogenic carcinoma. It is difficult to identify from other clear cell tumours of the head and neck region. It is crucial to distinguish it from other clear cell lesions because of its aggressiveness.

BACKGROUND: The BRAF p.V600E genetic variant facilitates the pathogenesis of various tumors by triggering tumor proliferation and progression. The aim of this study was to analyze the prevalence of BRAF p.V600E in benign mixed epithelial and mesenchymal and malignant odontogenic tumors. In addition, we discussed the different detection methods used to assess for aberrant BRAF.
METHODS: This systematic review followed the PRISMA guidelines and was registered in Prospero (CRD42023445689). A comprehensive search of the PubMed/MEDLINE, Scopus, Web of Science, and Embase electronic databases was performed to answer the question \"What is the prevalence of the BRAF p.V600E mutation in benign mixed and malignant odontogenic tumors?\" The methodological quality of the selected studies was assessed using the JBI\'s Critical Appraisal Tool.
RESULTS: Initially, 387 records were identified, but only 11 articles met the inclusion criteria. A total of 70 patients with benign mixed epithelial and mesenchymal odontogenic tumors and 63 with malignant odontogenic tumors were included in the analysis. We found that the BRAF p.V600E mutation had a prevalence of 31.42% in mixed tumors and 26.98% in malignant odontogenic tumors. Moreover, immunohistochemistry showed high concordance with DNA-based molecular methods.
CONCLUSIONS: In general, the BRAF p.V600E variant exhibited a prominent prevalence in mixed and malignant odontogenic tumors. However, most of the findings are based on small cohorts of patients and further studies with larger cohorts are needed.

Odontogenic carcinosarcoma (OCS) is a rare malignant odontogenic tumor (OT) with only a few cases reported in the literature. Its synonyms are ameloblastic carcinosarcoma, malignant mixed OT. It is characterized by a true mixed tumor showing malignant cytology of both epithelial and mesenchymal components. The tumor invaded into adjacent tissues by destroying the bone. A 24-year-old patient visited the outpatient clinic of GITAM Dental College and Hospital, with a chief complaint of growth in the lower right back tooth region for 6 months. Based on clinical and radiographic features, it has been diagnosed as an aggressive central jaw lesion. The patient was further referred for histological examination for confirmatory diagnosis. It has been diagnosed as an adenomatoid OT. The OCS most commonly affects the posterior part of the mandible. A larger number of cases were reported recently, and prolonged follow-up is needed to further clarify the nature of OCS.

Clear cell Odontogenic Carcinoma (CCOC) is an uncommon malignant odontogenic tumor (MOT). It is the fifth most common MOT. A systematic review is presented of reported cases, case series and retrospective studies of CCOC, to determine trends in presentation, diagnostic features, treatment, and patient outcome. Searches of detailed databases were carried out to identify papers reporting CCOC. The variables were demographics, patient symptoms, tumor location, histopathological findings, immunohistochemical studies, treatment, follow-up, and recurrence. 117 cases were identified; CCOC was most frequently seen in mature females 65% (n = 76). The total average age was 55.4 with a range from 17 to 89 years, for females 56.4 and males 53.6 years. The mean size was 3.41 cm. The most common location was in the mandibular body 36.2% (n = 42), followed by the anterior mandible 23.3% (n = 27). The most common clinical presentation was a swelling 80.4% (n = 74), and the main symptom was pain 41.3% (n = 31), followed by painless lesion 24% (n = 18). The most common Immunohistochemistry positive expression was CK19, EMA, and CEA, and for special staining periodic acid Shiff (PAS); 97% of cases were treated surgically. The average follow-up was 30.3 months, and recurrence was reported in 52.4% of the cases. Conclusion: CCOC shows a strong predilection for the body and anterior mandible, and females are more frequently affected. CCOCs can be painful and the principle clinical sign is swelling, CCOCs can metastasize, and the prognosis is fair.