Odontogenic Myxoma: A 23-Year Retrospective Series of 38 Cases.

Odontogenic myxoma (OM) is an uncommon benign odontogenic tumor arising in the jaw. Though it has slight histologic overlap with other entities, definitive diagnosis is imperative considering the tumor's aggressive nature, high recurrence rate, and necessity of radical surgical intervention in large-sized lesions. With IRB approval, a retrospective search of the University of Florida College of Dentistry Oral Pathology Biopsy Service archives from 1994 to 2017 for diagnosis of OM of the jaw was performed. Biopsy reports and original slides for each case were assessed and reviewed along with any accompanying radiographs to confirm the diagnosis. Immunohistochemical staining was utilized to exclude entities with histologic overlaps, such as intraosseous myxoid neurofibroma. A total of 38 cases were included. The patients' age ranged from 6 to 84 years, with a mean age of 37.47 years. Females comprised two-thirds of the cases (n = 25) versus males (n = 13). The mandible was the most affected at 60.5% (n = 23), followed by maxilla 39.4% (n = 15). Posterior jaw involvement was higher than anterior in both the mandible (n = 20 versus n = 3) and the maxilla (n = 11 versus n = 4). Most lesions presented clinically as expansile masses with variable radiographic appearance. The clinical impression from submitting providers included "gelatinous masses", abscesses, odontogenic lesions, fibro-osseous lesions, soft tissue or bone neoplasms, and reactive gingival lesions. A consensus of odontogenic myxoma as a diagnosis was rendered for 30 cases (79%), while in 8 cases (21%) that exhibited a more fibrous stroma was identified as fibromyxoma. OM may exhibit a varied demographic and clinical profile with a wide spectrum of histologic presentations. Pathologists should be sentient of this variability in order to arrive at an accurate diagnosis and correctly manage these patients.

An Analysis of Clinical and Histopathologic Features of Fibrous Dysplasia of the Jaws: A Series of 40 Cases and Review of Literature.

Fibrous dysplasia (FD) is a rare condition commonly involving the jaws. While FD has a typical clinical and histological presentation, considerable variation exists. Moreover, overlap of features with other disorders is possible. This study serves to characterize the features of a large case series of FD of the jaws. With IRB approval, the University of Florida Oral Pathology Biopsy Service archive was retrospectively searched from 1994 to 2015 for cases of FD. Epidemiological data, location, duration, clinical and radiographic appearance, clinical impression and exact microscopic diagnosis were recorded. The average age was 37.3 years (range 7-87 years) with majority of cases in females (67.5%). The most common ethnicity was Caucasian. Maxillary location was predominant (59%), followed by mandible (38%) and multiple locations (3%). Expansion was reported in 78% of cases. Radiographically, most cases exhibited ground glass opacity, however some presented with a mottled or mixed radiopaque/radiolucent appearance. Histologically, a wide variation in terms of stromal cellularity, presence of osteoblastic rimming, and presence of calcified material mimicking cemento-osseous dysplasia was observed. Clinicians and pathologists should be cognizant of the significant variability in clinical, histopathologic, and radiographic presentation of FD, which may pose a diagnostic challenge.

Lichenoid Characteristics in Premalignant Verrucous Lesions and Verrucous Carcinoma of the Oral Cavity.

Verrucous hyperkeratosis (VH), verrucous carcinoma (VC) and the relentless, truly pre-malignant variant proliferative verrucous leukoplakia often exhibit lichenoid histologic features that may create a diagnostic dilemma for pathologists. This study aims to evaluate and categorize the frequency and the histopathologic patterns of lichenoid features seen in these lesions. Following IRB approval, cases of VH and VC from 1994 to 2014 were retrieved from the archives of UF Oral Pathology Biopsy Service. A panel of 4 board-certified oral and maxillofacial pathologists reviewed and scored the presence or absence of 5 lichenoid features: band-like infiltrate (BLI), saw tooth rete ridges (STRR), interface stomatitis (IS), civatte bodies (CB), and basement membrane degeneration (BMD). Cases not fulfilling the stringent selection criteria were excluded. A total of 70 cases of VH and 56 cases of VC were included. Approximately 25% of both VH and VC cases exhibited 3 or more lichenoid features. By Chi square testing, BLI (p = 0.000), IS (p = 0.005), and CB (p = 0.026) were significantly more common in VC than VH. Gingival lesions had significantly less frequent BLI (p = 0.004) and IS (p = 0.024) versus other sites. However, STRR was significantly more common in VH than VC (p = 0.000) in the gingiva. (p = 0.002). Statistical analysis revealed that the only significant valid association was the increased presence of band-like infiltrate in VC over VH (p = 0.001). Lichenoid features are common in both VH and VC and may represent a nonspecific inflammatory response to the dysplasia or malignancy rather than concomitant lichenoid disease. This could lead to significant under diagnoses of these premalignant or potentially malignant lesions by pathologists.

Direct immunofluorescence testing results in cases of premalignant and malignant oral lesions.

OBJECTIVES: Oral premalignant and malignant lesions may mimic oral lichen planus (OLP) clinically and microscopically. OLP often shows basement membrane fibrinogen positivity on direct immunofluorescence testing (DIF). This study examined fibrinogen positivity in oral premalignant lesions and squamous cell carcinoma. STUDY DESIGN: The University of Florida Oral Pathology Biopsy Service records were searched for the years 2003 to 2013 for oral premalignant lesions and squamous cell carcinoma with concurrent DIF testing. Demographic, clinical, and DIF or histologic information was collected and analyzed. RESULTS: Sixty-eight fibrinogen positive lesions were identified within a total of 164 cases. Low-grade dysplasia and premalignant verrucous lesions made up the majority of the fibrinogen positive lesions (combined n = 43; 63.2%), and the most common locations in positive cases were the buccal mucosa, tongue, and gingiva. A lichenoid distribution of the inflammatory infiltrate significantly predicted fibrinogen positivity (P < .0005). CONCLUSIONS: Fibrinogen positivity may be seen in premalignant and malignant oral lesions increasing the risk of misdiagnosis.

Ameloblastic carcinoma with features of ghost cell odontogenic carcinoma in a patient with suspected Gardner syndrome.

Ameloblastic carcinoma and ghost cell odontogenic carcinoma are rare malignancies arising in odontogenic epithelium within the jaws. Gardner syndrome is a multifaceted autosomal dominant condition, which results in multiple dentofacial anomalies along with premalignant colon polyp formation and tumor formation in the skin and other organs. We report a case of ameloblastic carcinoma with features of ghost cell odontogenic carcinoma and extensive clear cell change and melanin pigmentation in a patient with clinical features of Gardner syndrome. To the best of our knowledge, odontogenic carcinoma arising in a patient with features of Gardner syndrome has not been reported previously. The clinical, radiographic, and histologic features of the case are discussed along with a review of the relevant literature.