Clinicopathological characteristics of desmoplastic ameloblastoma: A systematic review

The Effect of Conservative vs. Radical Treatment of Ameloblastoma on Recurrence Rate and Quality of Life: An Umbrella Review

Ameloblastoma is a rare, benign, but locally aggressive odontogenic tumor that originates from the epithelial cells involved in tooth development. The surgical approach to treating an ameloblastoma depends on the type, size, location, and extent of the tumor, as well as the patient's age and overall health. This umbrella review's aim is to summarize the findings from systematic reviews (SRs) and meta-analyses on the effect of radical or conservative treatment of ameloblastoma on the recurrence rate and quality of life, to evaluate the methodological quality of the included SRs and discuss the clinical management. Three electronic databases (PubMed, Scopus, The Cochrane Library) were checked. The primary outcome was the recurrence rate after surgical treatment, while the secondary outcomes were the post-operative complications, quality of life, esthetic, and functional impairment. The methodological quality of the included SRs was assessed using the updated version of "A Measurement Tool to Assess Systematic Review" (AMSTAR-2). Eighteen SRs were included. The quality of the included reviews ranged from critically low (three studies) to high (eight studies). Four studies were included in meta-analysis, and they revealed that the recurrence rate is about three-times more likely in the conservative treatment group compared to the radical treatment group, and this result is statistically significant. Despite the high recurrence rate, the latter was more appropriate in the case of smaller lesions and younger patients, due to better post-operative quality of life and reduced functional and esthetic impairments. Based on the results of this overview, conservative treatment may be recommended as the first-line approach for intraosseous ameloblastoma not involving soft tissue. However, given the expectation of a higher recurrence rate, it is advisable to reduce the interval between follow-up visits. However, further prospective studies are needed to establish the best treatment choice and follow-up period.

Unicystic ameloblastoma: A retrospective study on recurrent factors from a single institute database

OBJECTIVE

Unicystic ameloblastomas are a variant of ameloblastoma with a definite recurrence rate because of the biological behaviours of the tumour. The risk factors associated with disease recurrence were analysed in this retrospective study.

METHODS

A total of 132 patients with primary unicystic ameloblastoma reported in a tertiary hospital from 2005 to 2015 were analysed to identify the clinic-pathological and radiological factors associated with recurrence using univariate and multivariate Cox regression analyses.

RESULTS

The mean volume was 30.54cm3 ± 12.55 cm3, and this value differed significantly according to recurrence (p < 0.001). Root resorption and bone cortex/soft tissue invasion were also significantly associated with recurrence among unicystic ameloblastoma patients (p = 0.017 vs. p < 0.001, respectively). A new stage classification system was developed to predict disease recurrence of patients. The multivariate Cox regression analysis revealed that the new stage classification system was the only predictor of disease recurrence in unicystic ameloblastoma patients (p < 0.001), regardless of root resorption, position and site characteristics.

CONCLUSIONS

Volume, root resorption and bone cortex/soft tissue invasion were risk factors for disease recurrence among unicystic ameloblastoma patients. The new stage classification was an independent predictor of disease recurrence in patients with unicystic ameloblastoma.

Recurrence Rates of Intraosseous Ameloblastoma Cases With Conservative or Aggressive Treatment: A Systematic Review and Meta-Analysis

Objective

This study aimed to systematically investigate and compare the post-treatment recurrence of intraosseous ameloblastoma in patients treated with conservative or aggressive approaches.

Methods

Systemic searches of PubMed, Medline, Cochrane Library, and Embase databases from inception to October 28, 2020, were conducted. Studies that aimed to evaluate the recurrence of intraosseous ameloblastoma by conservative and aggressive treatment approaches were included.

Results

A total of 20 studies with 942 ameloblastoma cases were included. Fourteen studies included patients with ameloblastoma who received conservative treatment, and 16 studies reported the overall recurrence rate for patients undergoing aggressive treatment. The pooled results indicated that the recurrence rate for aggressive treatment [0.12, 95% confidence interval (CI) = 0.09–0.16] was significantly lower than that for conservative treatment, with a recurrence rate of 0.30 (95% CI = 0.23–0.39). Similar results were obtained when stratifying the participants by the histological classification. When trying stratification analysis following the original included studies, multicystic ameloblastoma presented a much higher recurrence rate than solid and unicystic ameloblastomas.

Conclusion

These findings supported the hypothesis that aggressive treatment might lead to a lower recurrence rate than conservative treatment. More studies and meta-analyses following the new histological classification of ameloblastomas are needed to validate and support the findings.

Retrospective analysis of Desmoplastic Ameloblastoma: Clinical review

BACKGROUND

Desmoplastic Ameloblastoma (DA) is a rare, true neoplasm of jaws with reported incidence of 4-13% among other variants of Ameloblastoma, however this appears distinct than the classic Ameloblastoma in anatomical distribution and clinical presentation. This is often mistaken as a fibro-osseous lesion because of its similar radiological appearance.

MATERIAL AND METHODS

To describe the clinical, radiographic and histopathological characteristics through a series of new cases of histologically proven DA including a case of an exceptionally large, recurrent lesion along with retrospective analysis of cases from literature available for an improved understanding of the behaviour and prognosis of DA. A total of 50 cases were analysed for the anatomical distribution, radiographic presentation and management. Out of the 50 cases, 47 cases were from the English literature reported from 2011 to 2019 and 3 were new cases.

RESULTS

DA showed a slight male predilection (male: female=1.17:1) with a predominance in the fourth and fifth decade of life. Mandibular involvement (52%) was more commonly seen with a marked tendency for the anterior region. Radiographically, most of the lesions presented mixed radiopacity with radiolucency(80%) and root displacement was observed in only 70.27 % cases. Recurrence rate of 26 .47 % was observed. Cases treated with resection resulted in lesser recurrence as compared to those treated with enucleation and curettage.

CONCLUSIONS

DA is distinguished by a peculiar display of clinicalopathological parameters. DA has tendency of local disposition and propensity of recurrence, which thus necessitates its aggressive management. It is not possible to conclude or report on the aggressive/recurrent nature and appropriate treatment modality for DA due to inadequate follow-up results.

Central Odontogenic Fibroma with the Presence of Large Fibroblasts of Varying Morphology

A patient with an odontogenic fibroma (OF) with the presence of fibroblasts of varying morphology is presented, and the main microscopic differential diagnosis is discussed. Case report: a 51-year-old man complained of a swelling in the anterior region of the mandible. The panoramic radiograph showed a radiolucent, well-defined multilocular image, with displacement of the roots of the left mandibular incisors and canine. A cone beam computed tomography examination revealed a hypodense image, with delicate bone spicules inside, divergence of the tooth roots and destruction of the buccal cortical bone. Under the differential diagnosis of a desmoplastic ameloblastoma or a squamous odontogenic tumor, an incisional biopsy was made. Microscopically, deeply collagenized tissue with scarce odontogenic epithelium islands, large fibroblasts of varying morphology and calcified material was observed. A diagnosis of OF was made. Surgical removal was carried out, and the specimen was examined. Identical aspects were found, and the immunohistochemical reaction for pan-cytokeratin was carried out to identify the odontogenic epithelial cells. The definitive diagnosis of OF was confirmed, and we emphasize the importance of the correlation of all characteristics for a definitive diagnosis.

Keratinocyte dissociation (desmolysis/acantholysis) in ameloblastoma

Ameloblastoma is the only odontogenic tumor that displays diversified histomorphological features with subtypes like follicular, plexiform, acanthomatous, granular cell, clear cell, desmoplastic etc. In this paper we presented an extremely unusual presentation of ameloblastoma, which is characterized by desmolysis or acantholysis of stellate reticulum-like cells caused due to keratinocyte dissociation. A 35-year-old male patient presented with a painless hard 3×3 cm swelling in the mandibular right posterior region in the past 4-5 months. Radiographic examination revealed a multilocular radiolucent lesion in the body of mandible with resorption of the roots. Histopathological examination revealed ameloblastic follicles with central cells showing keratinocyte dissociation leading to desmolysis/acantholysis. Desmolytic cells were seen as an isolated entity in the follicular space with round to polygonal shaped morphology. Future retrospective studies on archival samples of ameloblastoma are recommended to relook into identification of such rare phenomenon. This will help in better understanding of the incidence rate and biological behavior of this rare variant of ameloblastoma.

Clinicopathological study of ameloblastoma and detection of human papilloma virus by immunohistochemistry

Objective:

To study the clinocopathological factors and presence of Human Pappiloma Virus in ameloblastoma by immnohistochemistry.

Methods:

It was a cross sectional study on 50 surgical specimens of ameloblastoma, completed in six months. These were selected and processed for initial screening by H&E and then by immunohistochemistry (IHC) for detection of Human Papilloma Virus (HPV). The questionnaire was designed to study the clinicopathological factors associated in these patients. Sections of 4µm were cut, placed on special positive charged glass slides in the Department of Pathology, King Edward Medical University. It was then examined by the histopathologists for grading and scoring of these lesions. Chi Square test was used to assess the differences found in types of ameloblastomas. The p-value was smaller than 0.05 (p < 0.05).

Results:

The mean age of the patients (12-80 years old) was 38.6±15.1 years, with male-female ratio 2.84: 1. HPV was positive in 9 (18%), whereas negative in of 41 (82%) patients. Among the positive, reactive HPV with score-1 was 8 and score-2 was 1. According to histological variant, follicular was present in 78%, Plexiform pattern in 8%, Conventional and Desmoplastic variants in one patient each; and Cystic and Acanthomatous were seen in two and three patients respectively. The mandible was involved in 39 patients, maxilla and right maxilla involved in 4 patients each, right retromolar, cheek and angle of mandible was seen in one patient each. About 16% patients had anterior, 66% had posterior and 18% had both anterior and posterior regions involved. Among the HPV positive reactive statistically, no significant difference was found with smoking, Paan and exposure to pesticides, factory or mine (p-value > 0.05). Among HPV positive reactive patients, eight had ameloblastoma whereas, 1 had ameloblastomic fibroma. There was no statistical significance of type, location and region of tumor in HPV positivity.

Conclusion:

Mandible and posterior region was more commonly involved. Follicular pattern was most common. There was no effect of exposure to pesticides, factory or mine, smoke and human papilloma virus in the etiology of ameloblastoma because only 18% of patients showed the association of HPV16

Three-dimensional radiographic features of ameloblastoma and cystic lesions in the maxilla

OBJECTIVES

To characterize the radiographic features of maxillary ameloblastoma (AM), odontogenic keratocyst (OKC) and dentigerous cyst (DC) comparatively by using spiral CT and cone beam CT (CBCT).

METHODS

Clinical records, histopathological reports, and nonenhanced spiral CT or CBCT images of 191 consecutive patients with primary maxillary AMs, OKCs, or DCs were retrospectively acquired, and radiographic features were analyzed.

RESULTS

The study included 118 males and 73 females (age: 5-84 years). 72.0% of AMs and 84.3% of OKCs originated from the posterior maxilla, while 69.6% of DCs occurred in the anterior maxilla. Among 25 AMs, 44.0% were of desmoplastic type, with honey-combed appearance. 84.0% of AMs were circular or oval in shape, 84.0% expanded buccally, and 36.0% invade the nasal floor. Among 89 OKCs of 88 patients, 61.8% were circular or oval, 58.4% expanded buccally, 49.4% were dentigerous, 41.6% nearly filled the maxillary sinus, and 13.5% invaded the nasal floor. 93.7% (74/79) of DCs enveloped a single tooth, and the tooth-cyst relationship was centripetal in 35, eccentric in 30, and circumferential in 9. Moreover, 98.2% (55/56) of the cysts enveloping a supernumerary tooth were DCs, while 80.9% (38/47) of the cysts enveloping the third molar were OKCs.

CONCLUSIONS

Maxillary AMs tend to grow with buccal expansion and invade the nasal floor, and DAs with honey-combed lobularity are common. Maxillary OKCs have variant shapes and tend to invaginate the maxillary sinus. The tooth-cyst relationship of dentigerous OKCs and DCs can be centripetal, eccentric, or circumferential.

Ameloblastoma: Reconstruction Using Titanium Plates adapted Using Stereolithographic Models

Ameloblastoma is a benign but locally invasive odontogenic tumor that causes significant morbidity. The aim is to study an ameloblastoma treatment with reconstruction using titanium plates adapted using stereolithographic models. A 48-year-old female patient referred due to asymptomatic osteolytic lesion between teeth 47 and 48 discovered during routine radiographic study. The pathoanatomical study described a desmoplastic ameloblastoma. Due to the possibility of it being a malignant lesion, a computerized axial tomography scan was performed, which showed that the tumor was not malignant. A stereolithographic model was prepared to make the cutting guides and facilitate fitting of reconstruction plates. Three-dimensional printing technology enables fast, accurate mandibular reconstruction, helping to shorten operation time.