Maxillary dentigerous cyst showing squamous odontogenic tumor-like proliferation: surgical approach and literature review

Squamous odontogenic tumor (SOT) is a rare benign neoplasm of the jaw that likely arises from remnants of the dental lamina. It is a slow-growing lesion, with a radiolucent appearance in the central variant. Microscopically, SOT shows islands of squamous epithelium supported by fibrous stroma. In rare cases, squamous odontogenic tumor-like proliferation (SOT-LP) can be observed arising from odontogenic cysts (SOT-LPOC). Herein, we describe the case of a 42-year-old man who presented with discreet bleeding in the maxillary gingiva. Imaging revealed a well-defined, ovoid-shaped lesion with sclerotic margins involving tooth #18 in the intraosseous location. Fine needle aspiration supported the cystic nature of the lesion. After surgery, microscopy revealed a dentigerous cyst showing SOT-LP features. There was no recurrence after a 3-year follow-up. To the best of our knowledge, this is the first report of a dentigerous cyst showing SOT-LP features in the maxilla. Such cysts should be identified to avoid misdiagnosis, with the finding having therapeutic and prognostic implications.

Squamous odontogenic tumor: report of a case of unusual involvement / Tumor odontogênico escamoso: relato de um caso de envolvimento incomum

ABSTRACT The squamous odontogenic tumor (SOT) is defined as a very rare benign neoplasm, locally infiltrative and can extend to neighboring structures. This study aimed to report a case of SOT unusual involvement. A female patient, 56-year-old, smoker showed mild swelling in the chin region in the portion between the left canine and right first premolar. Axial, coronal and sagittal images showed expansive hypodense lesion in the mandibular symphysis and parasymphysis. Partial removal of the lesion was performed, which led to the diagnosis of SOT. The patient presented no recurrence during 4 years and 2 months follow-up.

RESUMO O tumor odontogênico escamoso (TOE) é definido como uma neoplasia benigna rara, localmente infiltrativa, podendo estender-se a estruturas vizinhas. Objetivou-se relatar um caso de TOE de acometimento incomum. Paciente do sexo feminino, 56 anos de idade, fumante, demonstrou leve aumento de volume na região do mento na porção compreendida entre o canino esquerdo e o primeiro pré-molar direito. Imagens axial, coronal e sagital demonstraram lesão expansiva hipodensa na sínfise e na linha média mandibular. Fez-se a remoção parcial da lesão, o que levou ao diagnóstico de TOE. A paciente não apresentou recidiva durante quatro anos e dois meses de acompanhamento.

Simultaneous occurrence of an odontogenic keratocyst and squamous odontogenic tumor in the mandible : a case report and immunohistochemical study

A squamous odontogenic tumor (SOT) is rare disease and it is believed to originate from epithelial rests of Malassez of the periodontal membrane. Neither sex nor site predilection in either jaw has been established. Some lesion can be shown in juxtaposition in tooth roots. Although most lesions remain smaller than 2 cm, our cases involved a half of left mandibular ramus. The exact pathogenesis is still unknown. We report a case of SOT including the results of immunohistochemical study of pancytokeratin and p53.