Ameloblastic fibrosarcoma

Ameloblastic fibroma is a rare mixed odontogenic benign tumor that can occur in either mandible or maxilla but mostly it is found in posterior region of mandible. It can present either peripherally or centrally with a majority of the cases predominantly occurring in first two decades of life and mostly affects male patients. It is characterized by epithelial islands and cords submerged in ectomesenchyme that bear resemblance to the dental papilla and enamel organ but without actual hard tissue formation. Ameloblastic fibroma is a rare odontogenic tumor consisting of neoplastic epithelial and mesenchymal tissues...

The advances in molecular technologies have allowed a better understanding of the molecular basis of odontogenic cysts and tumours. PTCH1 mutations have been reported in a high proportion of odontogenic keratocyst. BRAF p.V600E are recurrent in ameloblastoma and KRAS p.G12V/R in adenomatoid odontogenic tumour, dysregulating the MAPK/ERK pathway. Notably, BRAF p.V600E is also detected in ameloblastic carcinoma, but at a lower frequency than in its benign counterpart ameloblastoma. Recently, adenoid ameloblastoma has been shown to be BRAF wild-type and to harbour CTNNB1 (β-catenin gene) mutations, further suggesting that it is not an ameloblastoma subtype...

Ameloblastic fibrosarcoma (AFS) is an extremely rare malignant odontogenic tumor. It is composed of benign odontogenic epithelium, resembling that of ameloblastoma, and a mesenchymal part exhibiting features of fibrosarcoma. The development of this lesion in the jaws is either de novo or from preexisting ameloblastic fibroma which has been well documented. The most commonly affected site within the jaw is the posterior mandible. These tumors show local aggressiveness and a high tendency to recur. We present a case of a 33-year-old female patient with swelling of the right posterior mandible for 2 months and progressive paresthesia of the same region for the past 6 months...

Ameloblastic fibro-odontosarcoma (AFOS) now designated as odontogenic sarcoma is an extremely rare odontogenic tumor, which histologically presents as a biphasic neoplasm with a malignant mesenchymal component plus ameloblastic epithelium. Here we report a 27-year-old Chinese female with the complaint of a painful swelling for half a month in the right mandible. A segmental mandibulectomy, with an immediate mandibular reconstruction using a free vascularized osteocutaneous fibular flap was performed using surgical guide models...

Although several types of odontogenic tumors share the same mutations in MAPK pathway genes, their effects on MAPK activation remain unclarified. This study aimed to evaluate the associations between these mutations and ERK phosphorylation in ameloblastoma and mixed odontogenic tumors (MOTs) and to analyze the expression pattern of phosphorylated ERK (p-ERK) for determining the involvement of MAPK activation in the development and progression of odontogenic tumors. Forty-three odontogenic tumors consisting of 18 ameloblastomas and 25 MOTs were analyzed for BRAF, KRAS, and NRAS mutations by Sanger sequencing...

BACKGROUND: Ameloblastic fibromas and ameloblastic fibrosarcomas are rare odontogenic tumors, and controversy exists in the classification of cases presenting hard-tissue production: Ameloblastic fibrodentinoma (AFD) and ameloblastic fibro-odontoma (AFO). These cases are currently considered "developing odontomas" (hamartomatous lesions). AIM: To analyze the clinicopathologic features of these lesions and discuss the changes in the 2017 World Health Organization classification...

Ameloblastic fibrosarcoma (AFS) is the most common odontogenic sarcoma, but the incidence is relatively low, and its molecular biology is poorly understood. We experienced a young female patient with a rapidly growing soft tissue tumor of the left maxilla, which eventually occupied the left side of the oral cavity. Histologically, the tumor mainly consisted of a proliferation of atypical spindle to polygonal cells without any specific differentiation, but a small number of benign odontogenic epithelial foci mainly in the tumor periphery were also noted; thus, a diagnosis of AFS was made...

Giraffes ( Giraffa camelopardalis ) are commonly managed in zoos and conservation programs worldwide, but the current understanding of the occurrence and progression of neoplastic disease in this species is limited by the scarcity of published reports. This study collated documented cases of neoplasia on the basis of gross and histologic evaluation of ante- and postmortem samples. In total, 30 giraffes from 22 institutions across the United States were included. Subspecies was not reported in all cases, but those identified included Masai ( Giraffa camelopardalis tippelskirchi ), Rothschild ( Giraffa camelopardalis rothschildi ), and reticulated subspecies ( Giraffe camelopardalis reticulata )...

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An ameloblastic fibroma (AF) is a proliferative mixed tumor which includes components of both odontogenic epithelium and mesenchymal tissue. It is a relatively rare neoplasm, accounting for approximately only 1.5－4.5% of odontogenic tumors. This case report describes an AF that occurred in the mandibular anterior tooth region in a 9-year-old girl who presented with the chief complaint of swelling in the left mandibular anterior tooth region. Intraoral examination revealed a swelling along the labial gingiva, extending from the left mandibular lateral incisor region to the left mandibular canine...

The molecular pathogenesis of mixed odontogenic tumors has not been established, and understanding their genetic basis could refine their classification and help define molecular markers for diagnostic purposes. Potentially pathogenic mutations in the component tissues of 28 cases of mixed odontogenic tumors were assessed. Laser capture microdissected tissue from 10 ameloblastic fibromas (AF), 4 ameloblastic fibrodentinomas (AFD), 6 ameloblastic fibro-odontomas (AFO), 3 ameloblastic fibrosarcomas (AFS), and 5 odontomas (OD) were screened by next-generation sequencing and results confirmed by TaqMan allele-specific quantitative PCR...

Ameloblastic fibrosarcoma (AFS) is a rare, aggressive malignant odontogenic tumor. AFS is seen most frequently in second and third decades of life. We are reporting a case of a low grade AFS in a 21-year-old male complaining of a painless swelling in the right side of the maxilla. The patient was treated with surgical excision followed by radiotherapy, which is considered the most effective approach for most of soft tissue sarcomas. AFS has a high-reported recurrence rate (up to 37%); therefore, long-term surveillance for recurrence is crucial...

Ameloblastic fibrosarcoma (AFS) is a rare malignant odontogenic tumour classified by the WHO (1992) as an odontogenic sarcoma and defined as "a neoplasm with a similar structure to ameloblastic fibroma (AF) but in which the ectomesenchymal component shows the features of a sarcoma." The first report of AFS was published by Heath in 1887. AFS and related lesions are less frequently diagnosed than odontogenic carcinomas. Approximately two-thirds of AFSs seem to arise de novo, but others have developed in recurrent AF, in which the ectomesenchymal cells retain their embryonic appearance and develop malignant characteristics...

AIMS: Ameloblastic fibrosarcoma (AFS) is an aggressive odontogenic neoplasm featuring malignant mesenchymal stroma in addition to an ameloblastic epithelial component, and is hence considered to be the malignant counterpart of ameloblastic fibroma (AF). AFS is exceedingly rare, with <110 cases having been reported so far. Although BRAF mutations are recognised driver mutations in ameloblastoma, the molecular pathogenesis of AFS remains elusive. METHODS AND RESULTS: We herein describe seven AFSs that were analysed, for the first time, for mutations in the BRAF-NRAS pathway...

This study reports 2 odontogenic carcinosarcomas, including the clinicopathologic and immunoprofile characteristics of these rare tumors. The first case occurred in a 22-year-old male presenting a bilobular mass involving the gingiva and bone of the premolar region of the left mandible, with paresthesia of the lower lip. Microscopic examination revealed a tumor similar to ameloblastic fibrosarcoma, with atypical mesenchymal cells; however, the odontogenic epithelium also showed atypia. In the second case, a 16-year-old female had a painless, asymptomatic, large intraosseous mandibular lesion...

AFS is a rare tumor of odontogenic origin. Less than 100 cases have been reported so far in the literature. Due to its extreme rarity, we do not have clear management guidelines at present. The entire clinical spectrum and natural history of this uncommon malignancy is unknown. Most of the cases present with facial swelling along with varying degrees of oral signs and symptoms. AFS has higher incidence in male and common in third decade of life. However, presentation in female can be unique and may have a different course and outcome then what is known to us...

CONTEXT: This retrospective study was planned to ascertain the relative frequency of odontogenic tumors (OTs) in an Indian population in the light of the latest World Health Organization (WHO) classification. AIM: To compare data with various reports from other parts of the world. STUDY DESIGN: Retrospective study. MATERIALS AND METHODS: The histopathology records and archived slides of all lesions diagnosed as "OT" in the Department of Oral Pathology and Microbiology of Government Dental teaching institute, Mumbai, Maharashtra, India, were recovered from the period January 1981-December 2016...

OBJECTIVES: The aim of this study was to analyze the immunohistochemical expression of fatty acid synthase (FASN) and cyclooxygenase-2 (COX-2) in tooth germ (TG), ameloblastoma (AM), ameloblastic carcinoma (AC), ameloblastic fibroma (AF), and ameloblastic fibrosarcoma (AFS). STUDY DESIGN: Immunohistochemistry for FASN and COX-2 was performed in 10 TG, 44 AM, 10 AC, 9 AF, and 5 AFS specimens. The results were analyzed by using the immunoreactive score (IRS) and Kruskal-Wallis test followed by Dunn's post-test...

Ameloblastic fibro-odontoma (AFO) is a rare benign odontogenic tumor with the histologic features of ameloblastic fibroma (AF) but also contains enamel and dentin. It is most commonly observed in the pediatric population. Distinction between AFO and AF becomes important as ameloblastic fibromas are associated with higher recurrence rates of up to 18%, and 35% of these recurrent lesions can undergo malignant transformation to ameloblastic fibrosarcoma. Hence, for amelobastic fibroma, conservative curettage is recommended for the initial lesion and marginal resection is considered for recurrent cases...

INTRODUCTION: Odontogenic tumors (OTs) are a heterogeneous group of lesions that are derived from odontogenic apparatus comprised of odontogenic epithelium, ectomesenchyme, and/ or mesenchymal elements. The OTs show marked geographical variation. This study was conducted to analyze the epidemiology and clinicopathological presentation of OTs based on age, sex, and site. MATERIALS AND METHODS: This study was conducted in Department of Oral Pathology and Microbiology...