Proceedings of the 2023 North American Society of Head and Neck Pathology Companion Meeting, New Orleans, LA, March 12, 2023: Odontogenic Tumors: Have We Achieved an Evidence-Based Classification

Implant-supported prosthetic rehabilitation after Ameloblastomas treatment: a systematic review

“…Odontogenic tumors (OTs) are a heterogeneous group of lesions whose pathogenesis is associated with alterations in components of signaling pathways involved in tooth formation (Wnt, BMP, FGF, Shh, and Eda) [ 60 , 61 ]. The first accepted classification of OTs was published by WHO in 1971, then revised and updated in 1992, 2005, and 2017 [ 62 ], and finally, 5 years later, in 2022, thanks to advances in the technology of molecular tools used for clinical and research purposes. This new classification presents some modifications; however, based on the biological behavior and the origin of the tumor tissue, OTs are classified into benign and malignant; in turn, benign OTs are classified into epithelial, mixed (epithelial and mesenchymal), and mesenchymal, while malignant OTs are classified into carcinomas, sarcomas, and carcinosarcomas respectively [ 1 ].…”

Vascular Invasion-type Retraction Artifact in Ameloblastoma

“…The well-known microscopic indicators of ameloblastic carcinoma, such as nuclear pleomorphism and hyperchromatism, cellular crowding and budding, increased mitosis, a high Ki-67 index, and focal necrosis, are not so clear cut, and the literature is discordant as to their thresholds. 2,3 Neural invasion, if present, can assist the diagnosis of ameloblastic carcinoma, [2][3][4] but this may be challenging because benign neural involvement was described in a subset of mandibular ameloblastoma. 4 Moreover, it has long been recognized that neural tracking by non-neoplastic odontogenic epithelium is a normal anatomic feature.…”

“…4 Moreover, it has long been recognized that neural tracking by non-neoplastic odontogenic epithelium is a normal anatomic feature. 2,4 In the setting of cytological atypia, vascular invasion ˗ although infrequent (<30% of ameloblastic carcinomas 5 ) ˗ may be a decisive criterion of malignancy. 2,6 Unlike bona fide vascular invasion with therapeutic and prognostic implications, vascular pseudoinvasion resulting from intraoperative or postoperative mechanical displacement of a tumor or normal tissue into vascular spaces is an iatrogenic artifact.…”

“…2,3 Neural invasion, if present, can assist the diagnosis of ameloblastic carcinoma, 2–4 but this may be challenging because benign neural involvement was described in a subset of mandibular ameloblastoma. 4 Moreover, it has long been recognized that neural tracking by non-neoplastic odontogenic epithelium is a normal anatomic feature. 2,4 In the setting of cytological atypia, vascular invasion ˗ although infrequent (<30% of ameloblastic carcinomas 5 ) ˗ may be a decisive criterion of malignancy.…”

“…4 Moreover, it has long been recognized that neural tracking by non-neoplastic odontogenic epithelium is a normal anatomic feature. 2,4 In the setting of cytological atypia, vascular invasion ˗ although infrequent (<30% of ameloblastic carcinomas 5 ) ˗ may be a decisive criterion of malignancy. 2,6…”