CHRISMED Journal of Health and Research

CASE REPORT
Year
: 2016  |  Volume : 3  |  Issue : 1  |  Page : 79--82

Desmoplastic ameloblastoma


Aesha Imran, Sandhya Arun Kumar, Sriram, Satish Muthu Kumar 
 Department of Oral and Maxillofacial Pathology, Chettinad Dental College and Research Institute, Kelambakam, Chennai, Tamil Nadu, India

Correspondence Address:
Aesha Imran
Lecturer, Chettinad Dental College and Research Institute Kelambakkam, Chennai - 603 103, Tamil Nadu
India

Abstract

The most common odontogenic neoplasm, it accounts for only 1% of all jaw tumors. A variant of Ameloblastoma- Desmoplastic type is known for its unique features and propensity to recur. A 44 year old male patient, report with a swelling in anterior part of lower jaw. Radiograph reveals a mixed radiopaque and radiolucent lesion. Histopathology shows features of Desmoplastic ameloblastoma.



How to cite this article:
Imran A, Kumar SA, Sriram, Kumar SM. Desmoplastic ameloblastoma.CHRISMED J Health Res 2016;3:79-82


How to cite this URL:
Imran A, Kumar SA, Sriram, Kumar SM. Desmoplastic ameloblastoma. CHRISMED J Health Res [serial online] 2016 [cited 2020 Oct 31 ];3:79-82
Available from: https://www.cjhr.org/text.asp?2016/3/1/79/172393


Full Text

 Introduction



Ameloblastomas are odontogenic tumors of epithelial origin and are slow growing lesion with local infiltrative growth potential.[1] Based on clinical and radiographic features, generally they are classified into three clinical types which includes: (1) Conventional solid or multicystic intraosseous ameloblastoma (SMA) (2) unicystic ameloblastoma and (3) peripheral ameloblastoma [1] which is supported by differing therapeutic consideration and prognosis.[1] Desmoplastic ameloblastoma is traditionally considered to be a subtype of SMA and was initially reported by Eversole et al.[2] World Health Organization (WHO) 2005 histological classification of odontogenic tumors categorize desmoplastic ameloblastoma as a separate entity and defines it as variant of ameloblastoma with specific clinical, imaging, and histologic features.[3] We report a case of desmoplastic ameloblastoma in 44-year-old male patient based on typical clinical, radiological and histopathological features.

 Case Report



A 44-year-old male presented with a chief complaint of a hard swelling in the anterior part of the lower jaw for 3 months duration. On clinical examination extraorally, a mild swelling was seen in the anterior mandible region [Figure 1]a.{Figure 1}

Intraoral examination revealed expansion of the labial cortical plate causing obliteration of the labial vestibule in relation to left canine, left lateral, and left central incisor teeth. Swelling was non tender and bony hard in consistency with normal appearing overlying mucosa. Crowding of lower anterior teeth was evident [Figure 1]b. There was no evidence of lymphadenopathy or fistulae. The mandibular occlusal radiograph revealed a diffuse, ill-defined predominantly radio opaque lesion interspersed with fine radiolucent areas extending from mesial aspect of right second premolar to the distal aspect of left second premolar. Root displacement was seen in relation to 33 and 32 with no evidence of root resorption [Figure 2].{Figure 2}

Considering the clinical location, that is, anterior jaw region and the mixed radiographic pattern a provisional diagnosis of desmoplastic ameloblastoma was made with ossifying/cemento-ossifying fibroma, calcifying epithelial odontogenic tumor, ameloblastic fibro dentinoma/odontoma in the differential diagnosis.

Incisional biopsy was planned under local anesthesia; mucoperiosteal flap was raised in relation to the labial aspect of 33, 32, and 31 region. Representative lesional tissue was obtained by penetrating the labial cortical plate, and the tissue was sent for histopathological examination. Hematoxylin and Eosin stained sections basically showed follicles and islands of odontogenic epithelium with inconspicuous peripheral columnar ameloblast like cells, in the dense fibrous connective tissue stroma. Evidence of osseous metaplasia was seen within the stroma [Figure 3]a. Myxoid areas were seen immediately surrounding few of the small odontogenic epithelial islands [Figure 3]b.{Figure 3}

Correlating the clinical and radiographic features, a histopathological diagnosis of desmoplastic ameloblastoma was given and resection of the mandible from left second premolar region to right first premolar region was performed followed by autologous iliac bone graft [Figure 4]a and [Figure 4]b.{Figure 4}

 Discussion



Desmoplastic ameloblastoma is a rare odontogenic tumor, characterized by marked stromal desmoplasia. It is a benign locally infiltrative odontogenic epithelial neoplasm. It comprises 4–13% of all ameloblastomas. The highest incidence is in the Japanese population. Occurs in fourth to fifth decade of life, with no gender predilection and seen equally in males and females.[4] The commonly involved site includes anterior part of the mandible, this is in contrast to the conventional type of ameloblastoma.[4] Its location could be one of the reasons for early identification, as in our current case.

Philipsen and Reichart [5] in the revision of 1992 classification of odontogenic tumours suggested to include desmoplastic ameloblastoma as separate clinical variant based on its specific clinical, radiological, histological and biological behavior and the same was accepted in 2005 WHO classification of odontogenic tumours.[3]

The radiographic features of desmoplastic ameloblastoma differ in almost all cases from that of ameloblastoma which are classically described as a unilocular or multilocular radiolucency with well-defined borders, whereas desmoplastic ameloblastomas have a mixed radiolucent/radiopaque appearance in 64% of cases and are radiolucent in 36% of cases with ill-defined borders.[6]

The unique radiographic pattern which differs from that typical ameloblastoma is generally believed to be due to osseous metaplasia that occurs in the stroma.[4] However Takata et al.[7] believed that when desmoplastic ameloblastoma infiltrates the bone marrow spaces remnants of original non metaplastic bone that remain in the tumor tissue, can contribute to mixed radiographic appearance.

A confirmatory diagnosis of desmoblastic ameloblastoma was made by histopathological evaluation. The microscopic feature usually include (1) stromal desmoplasia, in the form of moderately cellular, fibrous connective tissue with abundant collagen, which is the most consistent and distinguishing feature (2) Islands of different shapes of odontogenic epithelium, (3) peripheral layer of cuboidal cells and (4) hypercellular central area composed of spindle-shaped or polygonal epithelial cells.[8]

Our case also revealed similar features having dense fibrous connective tissue which is the most consistent feature and it also had regions of the mature lamellar bone. This Histopathological feature may indicate the feature of local invasion and also accounts for a diffuse appearance on radiographs.

Prognosis

Since desmoplatic ameloblastoma tends to infiltrate into the bony trabeculae, curettage often reveals islands of tumor within the bone, which eventually leads to recurrence.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/ their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

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