The diagnostic utility of BRAF VE1 mutation-specific immunohistochemistry in ameloblastoma.

Ameloblastoma is a benign, locally aggressive odontogenic neoplasm with variable solid and cystic morphology. On account of its histologic variety, diagnostically challenging cases can bear resemblance to odontogenic keratocyst/keratocystic odontogenic tumor (KCOT) or dentigerous cyst (DC). BRAFV600E mutation has been reported to be specific for and frequent in ameloblastoma, and this study evaluated the usefulness of immunohistochemistry (IHC) using the BRAF VE1 mutant-specific antibody as a diagnostic adjunct in this setting. We investigated 46 ameloblastomas, 30 KCOTs, and 30 DCs. BRAF VE1 IHC was performed on all cases and allele-specific polymerase chain reaction (AS-PCR) for BRAFV600E mutation was performed on 30 ameloblastomas and any IHC-positive KCOT/DC. BRAF VE1 IHC was positive in 31/37 (83.8%) mandibular ameloblastomas but not in any maxillary ameloblastomas (0/9), KCOT (0/30), or DC (0/30). Equivocal staining was seen in 1/37 (3.3%) mandibular ameloblastomas. Of the 30 ameloblastomas subjected to AS-PCR, BRAFV600E mutation was identified in 19/23 (82.6%) mandibular ameloblastomas and 0/7 (0.0%) maxillary ameloblastomas. BRAFV600E mutant ameloblastomas were positive by IHC in 18/19 (94.7%) cases and equivocal in 1/19 (5.3%) cases. All 11 (100.0%) BRAF-wild type ameloblastomas were negative by IHC. BRAF VE1 is an excellent tool for the diagnosis of mandibular ameloblastoma but of limited utility in the maxilla, where it less commonly occurs and where BRAFV600E mutation is considerably less frequent.

Management of Mandible Angle Fractures With a Right Angle Drill: Description of Technique.

ABSTRACT: Management of mandible angle fractures can be challenging within the confines of the oral cavity where the use of linear instruments may result in structural weakness or malalignment secondary to improper placement. A right angle drill can facilitate a more ergonomic approach, with direct perpendicular placement of the instrument over the angle fracture. In addition, local soft tissue strain is minimized, and the need for a transcutaneous exposure can be avoided for additional plate placement. The right angle drill technique is simple, reproducible, and can be easily incorporated into routine mandible angle fracture management.

Giant Cell Lesions of the Jaws Involving RASopathy Syndromes.

Objective: Giant cell lesions of the jaws (GCLJ) may rarely occur in the setting of RASopathy syndromes such as Noonan syndrome or neurofibromatosis I. Recently, central giant cell granulomas (CGCG), the most common of the GCLJ, have been recognized as benign neoplasms characterized by Ras/MAPK signaling pathway mutations. This provides a rational basis for understanding GCLJ in RASopathy syndromes as syndromically occurring CGCG. This review aims to summarize the clinicopathologic features of syndromic CGCG and to review the salient clinical and craniofacial features of the syndromes in which they may rarely occur. Material and Methods: An electronic search in 3 databases was performed, looking for GCLJ/CGCG in RASopathy syndromes. Results: 124 CGCG in 56 patients were identified across 6 RASopathy syndromes. Median age at syndromic CGCG diagnosis is 11 years; 69.6% (39/56) patients developed two or more CGCG; 58.9% (33/56) presented with bilateral posterior mandibular CGCGs, mimicking cherubism. Of 88 CGCG with follow-up, 22.4% (13/58) of excised/resected CGCG recurred while 46.7% (14/30) of monitored CGCG showed continued growth. Conclusion: Syndromic CGCG involves multiple RASopathy syndromes and may mimic cherubism or, when solitary, sporadically occurring CGCG. Familiarity with other clinical findings of RASopathy syndromes is critical for appropriate diagnosis and patient management.