Unicystic plexiform ameloblastoma with mural proliferation: a full-blown lesion

Abstract

Ameloblastoma is the most common aggressive benign odontogenic tumour of the jaws and has received considerable attention due to its frequency, clinical subtypes and high tendency to infiltrate and recur. There are various types of this tumour and confusion still exists among clinicians as to its correct classification. Multicystic ameloblastoma is the most frequent subtype while unicystic ameloblastoma can be considered a variant of the solid or multicystic subtype. Unicystic ameloblastoma is considered a less aggressive tumour with a variable recurrence rate. However, its frequency is often underestimated. Ameloblastoma is often asymptomatic, presenting as a slowly enlarging facial swelling or an incidental finding on radiograph. It is seen in all age groups but is most commonly diagnosed in the third and fourth decades. We report a case of unusual unicystic ameloblastoma and present its clinical, radiological and full-blown histological changes and treatment modalities, providing new insights into ameloblastomas.

Luminal, Intramural Unicystic Ameloblastoma with Marked Fluid-Fluid Level: Validity of CT and MRI Findings

“…Radiographically, ameloblastomas show considerable variation on plain films, and are commonly classified as uni-or multilocular radiolucencies with well-defined margins, except for desmoplastic ameloblastoma, which has mixed radiolucent/radiopaque areas and ill-defined margins, similar to the situation seen with fibro-osseous lesions 25,31) . Unicystic ameloblastomas are usually unilocular, although rare cases show the characteristic soap bubble appearance of a multilocular lesion 2) . Furthermore, there can be varying degrees of bony expansion with a UA, and they sometimes have the so-called scalloped appearance.…”

Extensive ameloblastoma in young patient: 5-year follow-up with no recurrence using conservative treatment

“…According to the latest edition of the book on Head and Neck Tumors published by the World Health Organization (WHO) [9] at the beginning of 2017, ameloblastoma can be classified as: ameloblastoma, unicystic ameloblastoma or extraosseous/peripheral ameloblastoma, with the terminology solid or multicystic, used since the last WHO classification in 2005, being discarded as it has no biological meaning, while the term desmoplastic will no longer be used as a clinicalpathological entity but rather as a histological subtype. Ameloblastoma is regarded as the variant with the highest rate of recurrence, more aggressive [10] and more common than the unicystic or extraosseous form [11,12]. The final diagnosis is performed via a microscopic examination, however clinical examinations, and imaging examinations using radiography and computed tomography, help to provide a differential diagnosis [13].…”

Extenso ameloblastoma unicístico em mandíbula: relato de caso

“…Radiograficamente, os AUs apresentam-se como lesões císticas, uniloculares, geralmente em região posterior ou anterior de mandíbula 6,9 . Apesar de sua terminologia, o aspecto multilocular pode estar presente em AU, sendo esta característica mais comum para os ACs 10 . Ainda, é possível que a lesão esteja associada a um dente incluso e provoque reabsorções radiculares em unidades adjacentes 6,11 .…”

“…Uma vez que nenhuma das características clínicas ou radiográficas descritas são exclusivas do AU, o diagnóstico para esta lesão não pode ser predito antes do exame histológico da lesão inteira 12 . A microscopia dos AUs revela a presença de uma cápsula conjuntiva revestida por um epité-lio ameloblástico, com células colunares de polaridade invertida e com núcleos hipercromáticos, dispostas em paliçada 10 . Ademais, em algumas áreas, as células se arranjam mais frouxamente conforme o padrão de um retículo estrelado no órgão do esmalte 10 .…”

“…A microscopia dos AUs revela a presença de uma cápsula conjuntiva revestida por um epité-lio ameloblástico, com células colunares de polaridade invertida e com núcleos hipercromáticos, dispostas em paliçada 10 . Ademais, em algumas áreas, as células se arranjam mais frouxamente conforme o padrão de um retículo estrelado no órgão do esmalte 10 . Quando estas células epiteliais limitam-se ao revestimento cístico, afirma-se haver um padrão histológico luminal 8 .…”