Xanthoma of the Jaw Bones: Cases Series and Review of Literature

BACKGROUND

Intraosseous xanthomas are rare benign lesions sometimes associated with excess lipid production. Xanthoma of the jaw bones (XJB) was first reported in 1964, and fewer than 50 cases have been reported in the English literature to date. The etiopathogenesis of XJB is highly suggestive of a reactive process or a metabolic condition.

METHOD

Seven cases of XJBs were retrieved from the archives of 4 oral and maxillofacial pathology services. Clinical, radiographic and histopathologic features of all these cases were retrospectively analyzed. Immunohistochemical (IHC) stains for S100 and CD68 were performed.

RESULTS

All seven cases involved the mandible. Patients' age ranged between 13 and 69 years with an evenly distributed female to male ratio. One patient had a medical history of hyperlipidemia, but the medical and dental histories of the others were unremarkable. For most cases, XJB was an incidental finding discovered during routine radiographic examination. Swelling and cortical expansion were noted in a few cases. Radiographically, cases typically presented as either well-defined multilocular or unilocular lesions, which were either radiolucent or mixed radiolucent/radiopaque. All the lesions were treated with surgical curettage and no recurrence was observed during subsequent follow-ups. Each of the seven cases exhibited sheets of foamy macrophages. The diagnosis is established by exclusion of entities with overlapping microscopic features and involved correlation with the clinical, histological, radiographic and IHC profiles. Immunohistochemically, all the cases expressed diffuse positivity for CD68 and were negative for S100.

CONCLUSION

XJB is a rare lesion of unknown etiology, which may mimic other benign or reactive jaw lesions. Due to its rarity and the potential diagnostic challenges it presents, clinicians must remain vigilant and consider CXJ in their differential when assessing radiolucent jaw anomalies.

COVID-related mucormycosis mimicking dental infection

A recent increase in the prevalence of mucormycosis of the head and neck in patients who have recovered from COVID-19 following hospitalization has been reported. A Majority of the cases have been reported from India. Conditions such as diabetes mellitus, use of corticosteroids for other autoimmune conditions, organ transplant, immunosuppression, immunodeficiency, and malignancies especially hematologic ones, are all known risk factors for mucormycosis. Recently, hospitalization for COVID-19 has been added to the list of risk factors for opportunistic mucormycosis infection. This is likely attributable to the high doses and prolonged use of corticosteroids in the treatment of hospitalized COVID-19 patients. Case Description: Two patients with post-COVID-19 associated rhinocerebral mucormycosis presented with profound unexplained dental disease including tooth mobility and dental abscess mimicking periodontal disease. The patients were previously hospitalized for COVID-19 and received prolonged treatment with high doses of corticosteroids. The patients responded well to the surgical debridement with or without antifungal therapy. Conclusion: Oral healthcare providers including oral and maxillofacial surgeons, dentists, dental hygienists, and other dental practitioners can play a vital role in the recognition and early diagnosis of rhinocerebral mucormycosis given the large number of patients with severe COVID-19 infection who have recovered following hospitalization and/or received long-term high doses of immunosuppressive treatment.

A RARE CASE OF PERIPHERAL ADENOID AMELOBLASTOMA WITH DENTINOID

Adenoid ameloblastoma with dentinoid (AAD) is an extremely rare central neoplasm of the gnathic bones with no reported case of peripheral AAD. Adenoid ameloblastoma with dentinoid was first reported by Slabbert et al. in 1992 under the term "dentinoameloblastoma." However, the Armed Forces Institute of Pathology introduced the name "adenoid ameloblastoma with dentinoid" in 1994. Histologically, AAD shows features of ameloblastoma and adenomatoid odontogenic tumor along with a calcified product resembling dentin. The biological behavior of central AAD is not well established, though, in the literature, several reports consider it to be among the more aggressive odontogenic neoplasms, with a propensity for local invasion and recurrence. The demographic characteristics, clinical features, behavior, and prognosis of the peripheral AAD (PAAD) are unknown. To the best of our knowledge, this is the first reported case of PAAD in a 62-year-old woman.

Essentials of oral manifestations of leukemia for the dental practitioner

Oral lesions may be the initial or only manifestation of leukemia and can be the key to early diagnosis. The varied nature of presenting signs and dentists' general lack of familiarity with oral presentations makes diagnosis challenging. This retrospective review reports a series of cases of leukemia to familiarize dentists with the oral manifestations and facilitate earlier diagnosis or recognition of relapse of this life-threatening disease. Following institutional review board approval, the University of Florida Oral Pathology Biopsy Service archive from 1994 to 2018 was queried for all oral biopsies resulting in a diagnosis of leukemia. Cases with insufficient diagnostic information or extraoral manifestations were excluded. Demographic, clinical, and histologic findings were tabulated. Ten cases with 12 biopsy sites were identified. Men (n = 6) were affected more commonly. The mean age of the patients was 58.4 years (range of 17 to 88 years). The gingiva was the most frequently biopsied site (n = 6; 50%). Importantly, 40% of the patients (n = 4) had no prior diagnosis of leukemia. A wide spectrum of clinical impressions was rendered, pyogenic granuloma being the most common, and the reported duration of lesions ranged from several weeks to 6 months. The rarity of patients presenting with leukemia may lead to low levels of clinical suspicion, misdiagnosis, and delays in treatment. However, oral lesions may be the first and only manifestation of leukemia, and clinicians should be aware of the clinical characteristics of these oral presentations to ensure early diagnosis and treatment, thereby helping to reduce disease-related morbidity and mortality.

Adenomatoid odontogenic tumor: a series of 28 cases from a biopsy service

OBJECTIVE

Adenomatoid odontogenic tumor (AOT) is a benign odontogenic tumor with an excellent prognosis, often seen in children and young adults. The aim was to examine the spectrum of clinical, radiographic, and histologic attributes of AOT and assess clinician recognition of this entity. In addition, diagnostic considerations and treatment modalities were explored.

METHOD AND MATERIALS

With Institutional Review Board approval, archival cases of AOT from the University of Florida Oral Pathology Biopsy Service (1994-2019) were examined. Clinical and demographic data along with accompanying radiographs and original slides were reviewed.

RESULTS

A total of 28 cases of AOT were identified. These were all solitary in nature, with a mean age of 20.6 years (range 12-67 years). Most patients were under 20 (75.0%) with a definite female predilection (64.3%). Anterior jaws remained the most common location (85.2%), with a higher maxillary predilection (57.1%). Clinical impression included odontogenic lesions such as dentigerous cyst, lateral periodontal cyst, and odontogenic keratocyst.

CONCLUSION

The spectrum of features of AOT is described. As clinicians were unfamiliar with AOT, highly characteristic features of AOT and more unique variants are discussed extensively to improve diagnostic aptitude. Clinicians must remain aware of this entity, as treatment is minimal compared to other odontogenic entities.

Peripheral ameloblastic fibro-odontoma-Report of 2 cases of a very rare entity

Ameloblastic fibro-odontoma (AFO) is a rare benign mixed odontogenic tumor that affects children and young adults. AFO occurs mainly intraosseous. Extraosseous AFO is extremely rare. We report 2 cases of rare peripheral ameloblastic fibro-odontoma in 2- and 12-year-old female patients. Microscopic examination revealed a benign proliferation of odontogenic epithelium associated with a dentinoid material distributed within a cell-rich mesenchymal stroma resembling dental papilla. Simple surgical excision of the lesion is usually curative. There was no recurrence after a short period of follow-up. Clinicians should be cognizant of this rare entity, which can be considered in a differential diagnosis of gingival growths that are noted in early childhood.

Central odontogenic fibroma in association with brown tumor of hyperparathyroidism in a patient with neurofibromatosis type 1

We present a patient with bone abnormalities and a myriad of lesions secondary to his redeveloping renal failure and neurofibromatosis type 1 (NF1). A 21-year-old male renal transplant recipient with NF1 presented with painless masses and large, irregular radiolucent lesions in the maxilla and mandible. After histologic examination, the lesion was diagnosed as a central odontogenic fibroma (COdF) in association with a central giant cell lesion, most consistent with brown tumor of hyperparathyroidism. The bone changes were interpreted to be highly suggestive of renal osteodystrophy. Around 30 cases of hybrid central giant cell granuloma-like lesion in association with central odontogenic fibroma have been reported. This, to our knowledge, is the first reported case of brown tumor in association with COdF. Our case provides further evidence of the giant cell component as the initiating entity in these hybrid lesions.

Secretory Carcinoma of the Oral Cavity: A Retrospective Case Series with Review of Literature

Secretory carcinoma (SC) is an uncommon salivary gland neoplasm of the oral cavity that microscopically may mimic acinic cell carcinoma (ACC) and mucoepidermoid carcinoma (MEC). This study describes a series of SC in minor glands with a literature review. We performed a retrospective search for oral SC, within the archives of the University of Florida, Oral Pathology and Surgical Pathology Biopsy services from 2010 to 2018. A total of 10 SCs were identified in the oral and maxillofacial region, four of which were in the minor salivary glands. The demographic, clinical, histological, and molecular findings were aggregated for all 4 cases. Patient age varied from 30 to 60 years, with an average of 45 years. Two cases each were in female and male patients. Two cases presented on the labial mucosa, and one each on the hard and soft palate. Immunohistochemical (IHC) staining showed mammaglobin positivity in all cases, GATA3 positivity in two cases, S100 positivity in three cases, and SOX10 positivity in only one case. Fluorescence in situ hybridization demonstrated positivity for ETV6-NTRK3 fusion in 4 cases. Although oral SC is rare, pathologists should be aware of the histologic overlap between the SC and other salivary gland neoplasms such as ACC and MEC. A judicious application of IHC staining would aid in diagnosis. SC should be considered in the differential diagnosis for intraoral salivary gland tumors.

Case of squamous cell carcinoma of the tongue in a pregnant woman, with literature review

Oral squamous cell carcinoma (OSCC) is an extremely rare occurrence during pregnancy. OSCC accounts for less than 2% of all malignancies in pregnant women, with an average mortality rate of 36%. Understanding the features of this tumor during pregnancy is important; however, the paucity of reports in the literature makes this challenging. Case presentation: The following is a case presentation of a woman who was diagnosed with SCC of the tongue (TSCC) at 13 weeks gestation. The article also provides a review of the literature of TSCC affecting pregnant women aged 30 years and under. Conclusion: Although OSCC in young women of reproductive age is rare, recent literature suggests an increased risk for this age group. The rarity of OSCC in pregnancy may potentially lead to low clinical index of suspicion, misdiagnosis, and delay in treatment. Additionally, treatment modalities, prognosis, and the long-term impact on the developing fetus are not well established, due to rarity of OSCC in pregnancy. Further studies to identify specific etiologic factors are needed to establish the association of OSCC with pregnancy, aid in prevention, and improve treatment and outcome.

Oral Hairy Leukoplakia in Immunocompetent Patients Revisited with Literature Review

Oral hairy leukoplakia (OHL) is an Epstein-Barr virus (EBV) related lesion seen in severely immunocompromised patients especially, those with concomitant human immunodeficiency virus (HIV) infection. It has been rarely reported in immunocompetent patients. OHL most often presents on the lateral border of the tongue as an asymptomatic, white, and corrugated plaque that does not rub off. With Institutional Review Board (IRB) approval, the University of Florida Oral & Maxillofacial Pathology Biopsy Service archives spanning 1994-2020 were queried. All cases of OHL affecting immunocompetent patients were identified. Data related to age, gender, clinical presentation, results of Epstein-Barr virus in situ hybridization (EBER-ISH), and periodic acid-Schiff (PAS)-fungus stains were recorded. Medical history and histology of all cases were reviewed for confirmation of diagnosis. A total of 11 cases were identified, the majority of which were males (63.6%) with a mean age of 62 years. All patients were Caucasian. Lesions entirely were located on the lateral borders of the tongue. OHL should not be considered pathognomonic for HIV infection and should be included in the differential diagnoses of keratotic lesions affecting the lateral border of tongue even in immunocompetent elderly patients. The etiology of OHL in this group of patients is not clearly understood.

Calcifying epithelial odontogenic tumor: a case series spanning 25 years and review of the literature

OBJECTIVE

The calcifying epithelial odontogenic tumor (CEOT) is a rare benign neoplasm that makes up less than 1% of all odontogenic tumors. This study aims to describe a case series of CEOT spanning 25 years and to review and compare our results with the existing literature.

STUDY DESIGN

With institutional review board approval, all CEOT archival cases from the University of Florida Oral Pathology Biopsy Service between 1994 and 2019 were retrieved. A total of 20 cases were included. Based on current criteria, 2 cases that stained positively for CD1 a were excluded, because these most likely represented the amyloid-rich variant of central odontogenic fibroma.

RESULTS

Average patient age was 40 years. Females and males were affected equally (n = 10). The mandible was more commonly involved (60%, n = 12) than the maxilla (40%, n = 8). CEOT variants included incipient CEOT (10%, n = 2) and peripheral CEOT (10%, n = 2). One case exhibited features of adenomatoid odontogenic tumor in addition to CEOT. Congo red staining for amyloid was performed in 13 cases, all of which were positive.

CONCLUSION

Our results align with the literature. Awareness of the different variants of CEOT and of the separate but similar-appearing amyloid-rich variant of central odontogenic fibroma will help to ensure accurate diagnosis and appropriate treatment.

Proliferative Verrucous Leukoplakia: An Expert Consensus Guideline for Standardized Assessment and Reporting

The many diverse terms used to describe the wide spectrum of changes seen in proliferative verrucous leukoplakia (PVL) have resulted in disparate clinical management. The objective of this study was to produce an expert consensus guideline for standardized assessment and reporting by pathologists diagnosing PVL related lesions. 299 biopsies from 84 PVL patients from six institutions were selected from patients who had multifocal oral leukoplakic lesions identified over several years (a minimum follow-up period of 36 months). The lesions demonstrated the spectrum of histologic features described in PVL, and in some cases, patients developed oral cavity squamous cell carcinoma (SCC). An expert working group of oral and maxillofacial and head and neck pathologists reviewed microscopic features in a rigorous fashion, in combination with review of clinical photographs when available. The working group then selected 43 single slide biopsy cases for whole slide digital imaging (WSI) review by members of the consensus conference. The digital images were then reviewed in two surveys separated by a washout period of at least 90 days. Five non-PVL histologic mimics were included as controls. Cases were re-evaluated during a consensus conference with 19 members reporting on the cases. The best inter-observer diagnostic agreement relative to PVL lesions were classified as "corrugated ortho(para)hyperkeratotic lesion, not reactive" and "SCC" (chi-square p = 0.015). There was less than moderate agreement (kappa < 0.60) for lesions in the "Bulky hyperkeratotic epithelial proliferation, not reactive" category. There was ≥ moderate agreement (> 0.41 kappa) for 35 of 48 cases. This expert consensus guideline has been developed with support and endorsement from the leadership of the American Academy of Oral and Maxillofacial Pathology and the North American Society of Head and Neck Pathologists to recommend the use of standardized histopathologic criteria and descriptive terminology to indicate three categories of lesions within PVL: (1) "corrugated ortho(para)hyperkeratotic lesion, not reactive;" (2) "bulky hyperkeratotic epithelial proliferation, not reactive;" and (3) "suspicious for," or "squamous cell carcinoma." Classification of PVL lesions based on a combination of clinical findings and these histologic descriptive categories is encouraged in order to standardize reporting, aid in future research and potentially guide clinical management.

Marginal linear gingival leukoplakia progressing to "ring around the collar"-An ominous sign of proliferative verrucous leukoplakia

BACKGROUND

Potentially malignant lesions of the gingiva may frequently present as well-demarcated white lesions confined to the marginal gingiva. These lesions often become thick and verrucoid and spread along the marginal gingiva to encircle the tooth. Some cases of marginal gingival leukoplakia, over time, progress to extensively involve the gingiva fulfilling the criteria for proliferative verrucous leukoplakia (PVL). The objective of this study is to raise awareness of this pattern of leukoplakia by reporting a series of cases of marginal gingival leukoplakia.

METHODS

An Institutional Review Board approved retrospective search of University of Florida and University of Nebraska Medical Center oral biopsy services was performed for all gingival biopsies. Inclusion criteria included cases exhibiting marginal gingival leukoplakia, and with accompanying clinical images.

RESULTS

A total of 30 cases of marginal gingival leukoplakia were included. All cases presented as well-demarcated leukoplakias, either on the buccal or lingual gingival margin, or circumferentially forming a "ring around the collar" of single or multiple teeth. Eight patients had recurrent lesions and 12 had multifocal involvement. Six of the 12 patients with multifocal involvement presented with a "ring around the collar." The histopathologic diagnoses were representative of benign lesions in seven cases, premalignant in 13, and malignant or suggestive of malignancy in 10 cases. Seven patients had carcinoma at the time of first biopsy, whereas 6 cases showed progression at time of follow-up.

CONCLUSION

This study aims to raise awareness that marginal gingival leukoplakia may represent potentially malignant lesions, and if circumferential and/or thick, may be the first manifestation of PVL.

Squamous Odontogenic Tumor: Review of the Literature and Report of a New Case

PURPOSE

Squamous odontogenic tumor (SOT) is a rare, benign, locally infiltrative odontogenic tumor of the gnathic bones. It is composed of islands of bland, well-differentiated squamous epithelium of varying shape and size. Because of histologic overlap, SOT has often been overdiagnosed as ameloblastoma and squamous cell carcinoma. It thus becomes important to understand the clinical, radiologic, histopathologic, and treatment characteristics of this tumor.

MATERIALS AND METHODS

Using the PubMed and Google Scholar databases, we searched for reported cases of SOT published in the English-language literature. We were able to retrieve 49 acceptable cases and perform a comprehensive literature review of the intraosseous SOTs, with emphasis on their clinical, radiographic, and pathologic characteristics, as well as treatment strategies. In addition, we present an additional case of SOT affecting the posterior mandible in a 44-year-old female patient.

RESULTS

The tumor in the posterior mandible in our patient was accompanied by acute pain and treated by enucleation. Histopathologic evaluation showed variably sized islands of benign squamous epithelium scattered in a fibrous stroma, consistent with the diagnosis of an SOT. Uneventful healing was noted at the 1-month postoperative appointment. However, the patient was lost to long-term follow-up. Our literature review showed that the average age at the time of diagnosis of SOT is 34.2 years. Men and women are equally affected, and the tumor does not show a predilection for either jaw bone. The most common locations are the anterior maxilla and posterior mandible. Most SOTs are treated conservatively by enucleation or curettage, whereas aggressive or recurrent tumors require radical resection.

CONCLUSIONS

Careful evaluation of the excised specimen, with immunohistochemical investigations, may prove rewarding in differentiating an SOT from other odontogenic neoplasms and thus minimize the patient's chances of undergoing an unnecessary aggressive intervention.

Retrospective Study of Buccal Mucosal Salivary Neoplasms

Salivary gland neoplasms of the buccal mucosa are relatively rare and often present with an unusual histopathologic profile when compared with other intraoral locations. We present a series of minor salivary gland neoplasms of the buccal mucosa and discuss demographics, clinical presentation, and histologic findings. An IRB approved retrospective search of University of Florida Oral Pathology Biopsy Service archive from 1994 to 2018 for all salivary gland neoplasms of the buccal mucosa was undertaken. Data related to age, gender, clinical presentation, diagnosis, and category of neoplasm recorded. Review for consensus of diagnosis and immunohistochemical (IHC) testing on current diagnostic standards was performed and diagnoses updated based on results. Of 66 cases identified majority were females (72.7%) and age mean was 63 years. Benign tumors were 56.06% and 43.94% malignant, with Mucoepidermoid carcinoma (MEC) being commonest (26/66, 39.4%), followed by canalicular adenoma (CLA) (14/66, 21.2%), ductal papilloma (DP) (10/66, 15.2%), cystadenoma (CA) (8/66, 12.1%), basal cell adenoma (BCA) (4/66, 6.1%), and 1(1.5%) each for pleomorphic adenoma (PA), secretory carcinoma (SC), adenoid cystic carcinoma (ACC) and adenocarcinoma not otherwise specified (ACNOS). This study with respect to demographics and percentage of benign and malignant buccal mucosal salivary gland neoplasms is in conformity with the literature. It underscores the fact that both benign and malignant salivary gland neoplasms should be included in the differential diagnosis of submucosal buccal masses. Future larger multicenter studies with detailed treatment and outcomes data may aid and assist in further understanding the behavior, diverse histomorphology and prognosis of these neoplasms.

Carcinosarcoma Arising from Inverted Papilloma in a Patient with History of Radiotherapy for Sinonasal Squamous Cell Carcinoma

Patient: Male, 72-year-old

Final Diagnosis: Sarcomatoid carcinoma arising from inverted papilloma

Symptoms: Nasal mass • nasal obstruction

Medication: —

Clinical Procedure: Excsion

Specialty: Pathology

Oral Verruciform Xanthoma: A Series of 212 Cases and Review of the Literature

Verruciform xanthoma (VX) of the oral cavity is an uncommon, reactive lesion of unknown etiology. In this study, we present a large series of VX with analysis of demographics, clinical appearance, histologic presentation and extensive review of literature. To the best of our knowledge, this is the largest series of oral VX reported to date. Following IRB approval, all cases diagnosed as VX found in the archives of the University of Florida Oral Pathology Biopsy Service (1994-2018) were included. Patient age, gender, location, clinical appearance, clinical impression, and duration of each lesion was collected. A total of 212 cases were included in our database with a mean age of 61 years (range of 9-94), and a female: male ratio of 1.06:1. The most common location in descending order was the gingiva (n = 110, 51.2%), followed by palate (n = 41, 19.3%), buccal mucosa (n = 18, 8.5%), tongue (n = 20, 9.4%), vestibule (n = 13, 6.1%), lip (n = 4, 1.9%), floor of mouth (n = 3, 1.4%), and unspecified (n = 1, 0.5%). The lesions were most frequently pink in color, and most often described as bumpy, rough, verrucoid and/or papillary. Clinical impression in descending order was papillary (n = 67, 31.6%), not specified or unknown (n = 41, 19.3%), hyperkeratosis (n = 24, 11.3%), fibroma (n = 20, 9.4%), leukoplakia (n = 17, 8.0%), dysplastic lesion (n = 13, 6.1%), pyogenic granuloma (n = 7, 3.3%), granulomatous reaction (n = 5, 2.4%), lichen planus, VX (n = 4 each, 2.0%), pigmented, other lesions (n = 3 each, 1.4%), and salivary and periapical lesions (n = 2 each, 0.9%). Three of the lesions were recurrences. The demographics and clinical parameters of this case series were in concordance with that of previously published reports. In our series, only 4 cases were suspected as VX, demonstrating the lack of familiarity clinicians have with this lesion.

p16INK4a as a proliferation marker unrelated to HPV expression in odontogenic cysts and tumors

INTRODUCTION

p16INK4a is a tumor suppressor protein that retards cell cycle progression from G1 to S phase. Prior studies have evaluated p16INK4a expression in odontogenic keratocyst and ameloblastoma, but data regarding other odontogenic cysts and tumors have been sparse.

METHODS

With IRB approval, cases from the following entities were identified from archives of the UF Oral Pathology Biopsy Service (2005-2015): benign incidental odontogenic rest, dentigerous cyst, lateral periodontal cyst, calcifying odontogenic cyst, glandular odontogenic cyst, odontogenic keratocyst, orthokeratinized odontogenic cyst, adenomatoid odontogenic tumor, calcifying epithelial odontogenic tumor, and ameloblastoma. All cases were submitted for p16INK4a immunohistochemical testing.

RESULTS

Results were scored as follows: nuclear and cytoplasmic staining of <5% cells (score 0), 5%-25% (score 1), 25%-50% (score 2), >50% (score 3). No significant difference in p16INK4a staining was noted between odontogenic cysts and the listed odontogenic tumors (chi-square, P = .540). When comparing lesions with higher recurrence rates (over 25% as reported in the literature) versus lesions with low recurrence rates (under 25%), higher recurrence correlated to significantly higher p16INK4a positivity (chi-square, P = .001). Follow-up testing was performed on 18 cases with "2" or "3" p16INK4a expression scores for high-risk HPV strains through HPV in situ hybridization (ISH) messenger RNA testing with no cases exhibiting a positive result.

CONCLUSION

This study exhibits an association between increased p16INK4a positivity and odontogenic lesions with higher recurrence rates and highlights the role of p16INK4a as a progression marker unrelated to HPV expression in this group of pathologic entities.

Lichenoid reaction with granulomatous stomatitis: A retrospective histologic study of 47 patients

OBJECTIVES

Lichenoid granulomatous reaction can be subcategorized into lichenoid granulomatous dermatitis or lichenoid granulomatous stomatitis. It is described in the literature as demonstrating a band-like lichenoid infiltration with clusters of histiocytic or granuloma formation. In this study, we presented a large case series of lichenoid granulomatous stomatitis including demographics, histological features, and subcategories and compared findings with current literature.

METHODS AND MATERIALS

We retrieved all cases diagnosed with lichenoid reaction with granulomatous inflammation between January 1, 2000, and August 1, 2016, from the University of Florida Oral Pathology Biopsy Service Archives.

RESULTS

A total of 47 patients with tissue from 50 biopsy sites were included. The majority of the cases were noted in females (64%) with a mean age of 59 years (range 30-88). Most patients were Caucasian, and the most common sites in descending order were: gingiva, buccal mucosa, vestibule, tongue, lip, palate, and occasional multifocal involvement. Clinical impressions by the treating clinicians included leukoplakia, dysplasia, carcinoma in situ, squamous cell carcinoma, lichen planus, vesiculobullous disease, trauma, and allergy. The histologic features of these cases ranged from lichenoid mucositis with numerous aggregates of histiocytes to well-formed granulomas, in accordance with previous classifications of similar dermatologic lesions. All cases revealed positive CD 68 in the histiocytic infiltrates and were negative for microorganisms utilizing acid-fast bacilli, Grocott methenamine-silver, and periodic acid-Schiff stains.

CONCLUSION

Lichenoid granulomatous disease may be more common than previously reported; however, its etiology remains unknown and patients should be kept under long-term clinical follow-up.

Oral Melanomas: A Case Series of a Deadly Neoplasm

PURPOSE

To describe and discuss the demographic and clinical features of oral melanomas, which are relatively rare but deadly neoplasms, and list the criteria for their diagnosis to increase early detection.

MATERIALS AND METHODS

An institutional review board-approved retrospective search of oral melanomas was performed in the archives of the University of Florida Oral and Maxillofacial Pathology Biopsy Service (Gainesville, FL) from 2015 through 2018. Exclusion criteria included cases with inconclusive diagnosis, skin involvement, and missing clinical data or slide material. Of 7 patients with a diagnosis of melanoma of the head and neck region, 6 (87.5%) were found to be diagnosed with oral melanomas and met the inclusion criteria.

RESULTS

All 6 patients were at least 45 years (range, 45 to 87 yr). The male-to-female ratio was 4:2. Three patients were asymptomatic and 3 experienced symptoms, including pain, swelling, and tingling. Seven lesions were detected in these 6 patients. Three of these lesions were located on the maxillary gingiva, 2 were on the mandibular gingiva, and 2 involved the palate. Two lesions were diagnosed as spindle cell melanoma, 4 were diagnosed as melanoma, and 1 was diagnosed as a mucosal lentiginous melanoma.

CONCLUSION

Oral melanomas should be considered in the differential diagnosis of oral pigmented lesions, especially on the gingiva or palate, in middle-age and elderly patients. Oral melanomas have a male bias. In addition, supportive criteria enabling early diagnosis of oral melanomas is addressed.

Inter-observer Variability in the Diagnosis of Proliferative Verrucous Leukoplakia: Clinical Implications for Oral and Maxillofacial Surgeon Understanding: A Collaborative Pilot Study

The use of diverse terminology may lead to inconsistent diagnosis and subsequent mistreatment of lesions within the proliferative verrucous leukoplakia (PVL) spectrum. The objectives of this study were: (a) to measure inter-observer variability between a variety of pathologists diagnosing PVL lesions; and (b) to evaluate the impact of diverse terminologies on understanding, interpretation, and subsequent treatment planning by oral and maxillofacial surgeons (OMFS). Six oral pathologists (OP) and six head and neck pathologists (HNP) reviewed 40 digitally scanned slides of PVL-type lesions. Inter-observer agreement on diagnoses was evaluated by Fleiss' kappa analysis. The most commonly used diagnostic terminologies were sent to ten OMFS to evaluate their resulting interpretations and potential follow-up treatment approaches. The overall means of the surgeons' responses were compared by Student t test. There was poor inter-observer agreement between pathologists on the diagnosis of PVL lesions (κ = 0.270), although there was good agreement (κ = 0.650) when diagnosing frankly malignant lesions. The lowest agreement was in diagnosing verrucous hyperplasia (VH) with/without dysplasia, atypical epithelial proliferation (AEP), and verrucous carcinoma (VC). The OMFS showed the lowest agreement on identical categories of non-malignant diagnoses, specifically VH and AEP. This study demonstrates a lack of standardized terminology and diagnostic criteria for the spectrum of PVL lesions. We recommend adopting standardized criteria and terminology, proposed and established by an expert panel white paper, to assist pathologists and clinicians in uniformly diagnosing and managing PVL spectrum lesions.

Ulcerated Lesions of the Oral Mucosa: Clinical and Histologic Review

Ulcerated lesions of the oral cavity have many underlying etiologic factors, most commonly infection, immune related, traumatic, or neoplastic. A detailed patient history is critical in assessing ulcerative oral lesions and should include a complete medical and medication history; whether an inciting or triggering trauma, condition, or medication can be identified; the length of time the lesion has been present; the frequency of episodes in recurrent cases; the presence or absence of pain; and the growth of the lesion over time. For multiple or recurrent lesions the presence or history of ulcers on the skin, genital areas, or eyes should be evaluated along with any accompanying systemic symptoms such as fever, arthritis, or other signs of underlying systemic disease. Biopsy may be indicated in many ulcerative lesions of the oral cavity although some are more suitable for clinical diagnosis. Neoplastic ulcerated lesions are notorious in the oral cavity for their ability to mimic benign ulcerative lesions, highlighting the essential nature of biopsy to establish a diagnosis in cases that are not clinically identifiable or do not respond as expected to treatment. Adjunctive tests may be required for final diagnosis of some ulcerated lesions especially autoimmune lesions. Laboratory tests or evaluation to rule out systemic disease may be also required for recurrent or severe ulcerations especially when accompanied by other symptoms. This discussion will describe the clinical and histopathologic characteristics of a variety of ulcerated lesions found in the oral cavity.

Effect of patient and nurse ethnicity on emergency department analgesia for children with appendicitis in israeli government hospitals

BACKGROUND

Ethnicity is a risk factor for disparate Emergency Department (ED) analgesia. We aimed to explore ethnic variations in the administration of ED analgesia to children with acute appendicitis in Israeli government hospitals.

METHODS

Children discharged with an International Classification of Disease-Ninth Revision diagnosis of acute appendicitis between 2010 and 2015 were included. The association between patient ethnicity (Jewish, Arab) and analgesia administration (any, opioid) was assessed. Age, gender, triage category, pain score and time of arrival were tested as possible confounders. The effect of patient-nurse ethnic discordance (PNED) was examined.

RESULTS

Overall, 4714 children with acute appendicitis, 3520 Jewish and 1194 Arab, were cared for in the EDs; 1516 (32.2%) received any analgesia and 368 (7.8%) opioid analgesia. Stratified by pain score, no statistical differences were found in the administration of any or opioid analgesia between Jewish and Arab patients with either severe pain or moderate pain. In multivariate modelling adjusted for pain score and triage category, the rates of any analgesia for Arab and Jewish patients were 31.8% (95% CI, 30.9-32.6) and 36.5% (95% CI, 36.0-36.9), adjusted OR (aOR) = 1.16 (95% CI, 0.98-1.38), respectively. The rates of opioid analgesia for Arab and Jewish patients were 8.5% (95% CI, 8.2-8.9) and 7.9% (95% CI, 7.3-8.7), aOR = 0.77; (95% CI, 0.59-1.22), respectively. Jewish and Arab nurses treated proportionally fewer patients from the opposite ethnicity with any analgesia (p < 0.01).

CONCLUSION

Emergency Department analgesia was markedly low, and not associated with patient ethnicity. PNED was associated with decreased rates of analgesia.

SIGNIFICANCE

Emergency Department analgesia for children with acute appendicitis in Israeli government hospitals is markedly low. Patient-provider ethnic discordance may negatively influence the provision of analgesia. Significant efforts should be undertaken in order to increase analgesia provision rates and reduce social inequality.

Clinical characterization and treatment outcome of patients with burning mouth syndrome

Burning mouth syndrome (BMS) is a complex condition that affects the oral cavity, and data regarding effective treatment are limited. The purpose of this study was to explore the demographic and clinical information along with treatment outcomes for patients with BMS treated in a large referral center. Clinical records of the Oral Medicine Clinic at the University of Florida College of Dentistry were retrospectively searched for patients diagnosed between 2009 and 2014. Clinical data and treatment effectiveness were recorded. The records of 64 patients were included in this study. Women represented the majority of patients (81.2%), and the average age of all patients was 65 years. The most common systemic diseases were hypertension (59.4%), psycho-logical disorders (51.6%), and gastroesophageal reflux disease (50.0%). The majority of patients were taking 5 or more medications (70.3%). Treatment frequency and efficacy were as follows: a-lipoic acid, 47.5% frequency (57 prescribed treatments of 120 total treatments) and lasting improvement reported with 45.6% of prescribed treatments; clonazepam, 17.5% frequency (21/120) and improvement reported with 33.0% of prescribed treatments; oral disintegrating clonazepam, 15.8% frequency (19/120) and improvement reported with 52.6% of prescribed treatments; and topical vitamin E, 5.0% frequency (6/120) and improvement reported with 33.0% of prescribed treatments. Chi-square analysis indicated that a significantly better response to treatment was reported by women (P = 0.010) and patients who reported involvement limited to the tongue rather than multifocal oral involvement (P = 0.040); however, the significant relationships did not persist when the variables were evaluated together using logistic regression analysis. No other clinical or demographic features showed significant differences in response to treatment. Although treatment effectiveness in this study was variable and limited for some regimens due to infrequent usage, many of the patients reported alleviation of symptoms.

Dermatologic Lesions Submitted to an Oral and Maxillofacial Pathology Biopsy Service: An Analysis of 2487 Cases

Skin lesions are often submitted to oral and maxillofacial pathology practices. The purpose of this study is to evaluate the frequency, distribution, variability, and composition of dermatologic lesions within a large oral and maxillofacial pathology biopsy service. An IRB-approved retrospective search of skin lesions diagnosed at University of Florida oral and maxillofacial pathology biopsy service between 1994 and 2015 was performed. 2487 cases were included in the study. Gender was reported in 2466 cases, of which 59% were male and 41% female. Age was provided in 2367 cases and ranged from 2 weeks to 96 years with an average of 55 years. Location was indicated in 2473 cases. Lips were the most common (41.7%), followed by face (25.3%), neck (7.4%), nose (6.5%), periorbital (5.3%), ear (4.1%), and scalp (3.8%). Of the 2487 cases, five diagnoses (actinic keratosis/cheilitis, intradermal nevus, epidermal inclusion cyst, seborrheic keratosis, and basal cell carcinoma) constituted 84.4% of the cases. 69 of 2487 cases (2.8%) resulted in dermatopathologic consultation prior to final reporting. Skin lesions accounted for ~ 1.0% of all lesions submitted to an oral and maxillofacial pathology biopsy service. This study found a large variation in the dermatologic lesions submitted to an oral pathology biopsy service. Although most were routine in complexity, dermatopathology consultation was an important tool in the diagnosis of the more challenging cases. This study may help pathologists gain a better understanding of the frequency and variability of dermatologic lesions submitted to an oral and maxillofacial pathology biopsy service and promote more interdisciplinary consultation within the field. This study evaluated the incidence and scope of dermatologic lesions submitted to a large oral and maxillofacial pathology biopsy service over a long time period. A wide scope of lesions was found, and dermatopathology consultation was important to quality assurance.

Hybrid Central Odontogenic Fibroma with Giant Cell Granuloma like Lesion: A Report of Three Additional Cases and Review of the Literature

Central odontogenic fibroma (COF) is an uncommon intraosseous neoplasm of the gnathic bones which is composed of fibrous connective tissue, with or without calcifications, and variable amounts of inactive odontogenic epithelium. It makes up less than 5% of odontogenic tumors and is more commonly seen in females. Central giant cell granuloma (CGCG) is a locally destructive but benign lesion of the jaws containing osteoclast-like multinucleated giant cells in a fibrovascular stroma. CGCG makes up approximately 10% of all benign jaw tumors and typically occurs in females younger than 30 years of age. A hybrid lesion with histologic features of both COF and CGCG is very rare and was first described in 1992. To date, fewer than 50 cases of this lesion have been reported. In this study, we present three additional cases of COF developing in conjunction with giant cell granuloma-like lesion, as well as provide a comprehensive literature review. Two of the lesions presented in our study were located in the posterior mandible and one occurred in the anterior mandible. Buccal and/or lingual expansion was noted in two patients and no recurrence was reported. Histologically, all three lesions demonstrated a blend of odontogenic epithelial islands with numerous multinucleated giant cells in a highly cellular connective tissue stroma. Immunohistochemical staining with CK19 and CD68 highlighted the odontogenic epithelium and multinucleated giant cells respectively. The precise nature of these hybrid lesions remains obscure and additional molecular studies may be of help in understanding their pathogenesis.

Melanoma of the Oral Cavity: an Analysis of 46 New Cases with Emphasis on Clinical and Histopathologic Characteristics

Melanoma of the oral cavity is a rare malignancy that carries a poor prognosis. We identified 46 new cases of both primary and metastatic melanoma to the oral cavity. Following IRB approval, these cases were obtained from the Oral Pathology Biopsy Service archives of the UF College of Dentistry (1994-2014), the UK College of Dentistry (1997-2015), and the UM Medical Center (1988-2015). All slides were reviewed. The location, age, race, gender, clinical impression, duration of lesion, histopathologic diagnosis, and histopathologic features were recorded. Cases from the facial skin and those with an ambiguous diagnosis were excluded. Forty-six cases fulfilled the inclusion criteria with 32 primary cases, 11 known metastases, and 3 cases where metastasis could not be excluded. The primary cases included a total of 20 females and 12 males with an average age of 66.7 (range 27-95), and the majority (80 %) of the patients were Caucasian when race was known. Twenty-two of the 32 primary cases (68.8 %) were located in the maxillary mucosa, 5 in the mandibular mucosa or bone, and 5 in other locations. The clinicians' impressions varied from benign fibrous growths to high grade malignancies. The histopathology varied widely among the cases, however two cell types predominated (often in combination): epithelioid cells (50.0 %) and spindle cells (50.0 %). Only 53.1 % demonstrated melanin pigmentation. Oral melanoma remains one of the most diverse clinical and histopathologic diagnoses. Better understanding of this neoplasm may promote earlier diagnosis and may lead to improved outcomes.

MicroRNA-375 as a biomarker for malignant transformation in oral lesions

OBJECTIVE

Malignant transformation of oral premalignant lesions is the key process in the progression to oral squamous cell carcinoma (OSCC). Previously, we identified miR-7 and miR-21 as candidate oncogenes and miR-375 and miR-494 as candidate tumor suppressors in OSCC. We aim to evaluate these microRNAs as biomarkers of malignant transformation in oral premalignant lesions.

STUDY DESIGN

Formalin-fixed, paraffin-embedded samples from progressive premalignant lesions and paired sequential OSCC tumors at the same site were obtained from same patients (n = 31). Total RNA was extracted and analyzed for microRNA levels using real-time polymerase chain reaction.

RESULTS

MiR-375 expression in progressive lesions was clearly lower than in nonprogressive control lesions (average eightfold difference, P = .0004). Furthermore, the expression of miR-375 decreased significantly after the progression from premalignant lesion to OSCC (P < .0001). Receiver operating characteristic curve analysis revealed that miR-375 was able to differentiate between progressive and nonprogressive premalignant lesions (P < .0001).

CONCLUSIONS

MiR-375 downregulation in oral premalignant lesions is associated with a higher risk of malignant transformation.

A mutation creating an out-of-frame alternative translation initiation site in the GRHPR 5'UTR causing primary hyperoxaluria type II

Primary hyperoxaluria type II is a recessive genetic disorder caused by mutations in the GRHPR gene. Although several dozen mutations have been described, all affect coding or transcript splicing. A man suspected of having primary hyperoxaluria type II was heterozygous for a novel single-nucleotide deletion (c.694delC) in GRHPR affecting Gln(232) , which introduced a pre-mature termination (p.Gln232Argfs*3). Two 5'untranslated region (UTR) variants of unknown significance were also noted. We show that these two variants occur in cis, on the opposite allele, and introduce - immediately upstream of the canonical translation initiation site - a novel out-of-frame translational start site. In vitro studies using the GRHPR 5'UTR fused to a luciferase reporter show that the variant start site pre-empted initiation at the canonical translational start site, and this was corroborated within the broader context of 1.3 kb of the GRHPR proximal promoter. This latter mechanism may be underappreciated in general; reports of clinically significant functional variation of this type are extremely rare.

Extensively ossifying oral leiomyoma: a rare histologic finding

Oral leiomyoma are rare neoplasms of the oral cavity. Ossification within leiomyoma is not unusual but is mostly reported in leiomyoma of the deep soft tissue. Ossifying leiomyoma is extremely rare in the head and neck. We identified a total of three cases of extensively ossified leiomyoma in the head and neck in the literature including lesions in the lateral pterygoid muscle and orbit. To the best of our knowledge, only one case of extensively calcified leiomyoma has been reported in the oral cavity. We present two such rare cases of oral leiomyoma with extensive intratumoral calcifications and ossification. Ossified leiomyoma should be considered in the differential diagnosis of calcified or hard/firm soft tissue masses in the oral cavity.

The clinical and histologic presentation of gingival squamous cell carcinoma: a study of 519 cases

OBJECTIVES

Gingival squamous cell carcinoma (SCCA) often presents with benign features, which may lead to delay in treatment. This study describes the clinical and histologic characteristics of a series of gingival SCCA cases.

STUDY DESIGN

A retrospective consecutive case review was performed using the University of Florida College of Dentistry Biopsy service's database, which yielded clinical and histologic information on 519 cases of gingival SCCA.

RESULTS

The average age of affected patients was 72.3 years. The most common site was the mandibular posterior gingiva. Approximately 72% of lesions were present for >2 months at biopsy. The majority of clinicians considered a malignancy in their differential diagnosis (64%), although 15% considered only reactive lesions. Most of the carcinomas presented as exophytic masses and, histologically, were moderately differentiated.

CONCLUSIONS

Gingival SCCA may present with varied clinical and histologic appearances and should be considered in the differential diagnosis of benign appearing lesions of the gingiva.

Papillary variant of squamous cell carcinoma arising on the gingiva: 61 cases reported from within a larger series of gingival squamous cell carcinoma

Papillary squamous cell carcinoma (PSCCA) is a rarely occurring variant of squamous cell carcinoma (SCCA) with distinctive exophytic and papillary features and a more favorable prognosis than conventional SCCA. The larynx is the most commonly affected site in the head and neck. The oral cavity, oropharynx, sinonasal tract, and nasopharynx are also affected. Within the oral cavity cases have been reported on the alveolar ridge, oral mucosa, floor of the mouth, ventral tongue, and rarely other areas. We identified 61 cases of gingival PSCCA within the parameters of a larger study of 519 cases of gingival SCCA. We evaluated the clinical and histologic features of these lesions. The average age of the PSCCA patient was 74 years, with a very slight male predominance of 1.2:1. The mandible was affected nearly twice as often (64 %, n = 39) as the maxilla (35 %, n = 21, and 1 % of cases unspecified), and the most common location by far was the mandibular posterior region (52 %, n = 32). Most lesions were reportedly present over 2 months in duration (48 %, n = 29) prior to biopsy but a significant amount of clinicians were unsure of the duration of the lesion as well (36 %, n = 22). Only 10 cases (16 %) were reportedly present less than 2 months. The most common clinical presentation was that of an erythematous or mixed white and red exophytic mass (74 %, n = 45). 62 % (n = 38) of submitting clinicians considered a malignant or premalignant lesion in their differential diagnosis, but other clinical impressions included papillomas, reactive gingival lesions, and fungal infections. Histologically, 88 % (n = 52 of 59 cases graded) of the lesions were either well or moderately-well differentiated. PSCCA is a rare subtype of SCCA which has been reported infrequently involving the gingiva or alveolar ridges but should be considered by clinicians for the differential diagnosis of papillary gingival masses.

Tumor suppressor miR-375 regulates MYC expression via repression of CIP2A coding sequence through multiple miRNA-mRNA interactions

miR-375 interacts with five conserved target sites in the CIP2A coding region, whereas the CIP2A 3′ UTR is not conserved across mammalian species. Reexpression of the tumor suppressor miR-375 in cancer cells represses the expression of CIP2A, resulting in a decrease in the MYC protein level and leading to reduced cell proliferation, migration, and invasion.

MicroRNAs (miRNAs) are small, noncoding RNAs involved in posttranscriptional regulation of protein-coding genes in various biological processes. In our preliminary miRNA microarray analysis, miR-375 was identified as the most underexpressed in human oral tumor versus controls. The purpose of the present study is to examine the function of miR-375 as a candidate tumor suppressor miRNA in oral cancer. Cancerous inhibitor of PP2A (CIP2A), a guardian of oncoprotein MYC, is identified as a candidate miR-375 target based on bioinformatics. Luciferase assay accompanied by target sequence mutagenesis elucidates five functional miR-375–binding sites clustered in the CIP2A coding sequence close to the C-terminal domain. Overexpression of CIP2A is clearly demonstrated in oral cancers, and inverse correlation between miR-375 and CIP2A is observed in the tumors, as well as in NCI-60 cell lines, indicating the potential generalized involvement of the miR-375–CIP2A relationship in many other cancers. Transient transfection of miR-375 in oral cancer cells reduces the expression of CIP2A, resulting in decrease of MYC protein levels and leading to reduced proliferation, colony formation, migration, and invasion. Therefore this study shows that underexpression of tumor suppressor miR-375 could lead to uncontrolled CIP2A expression and extended stability of MYC, which contributes to promoting cancerous phenotypes.

CD44 expression in intraoral salivary ductal papillomas and oral papillary squamous cell carcinoma

CD44 is a transmembrane adhesion molecule which has been previously shown to be useful in the differentiation of benign papillary lesions from invasive carcinoma in several different areas including sinonasal mucosa and breast tissue. CD44 expression has previously been shown to be lost in invasive carcinoma and retained in benign papillary lesions in both of the above locations. In addition, studies have evaluated oral mucosal lesions for CD44 expression and found a loss with invasive squamous cell carcinoma when compared to normal epithelium, hyperplasia, and squamous papillomas, which stained particularly strongly. To the best of our knowledge, no study has evaluated CD44 expression when comparing salivary ductal papillomas in comparison to oral papillary SCCA. In this study 18 cases of intraductal papilloma were compared to 19 cases of oral papillary SCCA. Within the ductal papilloma group, all cases stained either absent (6%), weakly (33%), or moderately (61%) with 76% expressing the stain diffusely and 24% focally. In comparison, the papillary squamous cell carcinoma cases expressed the CD44 moderately (26%) or strongly (74%) with 100 % showing diffuse staining. Thus, the CD44 expression was contrary to expectation based on previous studies, which we hypothesize is due to the extremely well differentiated nature of papillary SCCA which expressed CD44 staining compatible with levels previously reported with oral squamous papillomas than invasive carcinoma.

The non-ossifying fibroma: a case report and review of the literature

The non-ossifying fibroma (NOF) is a benign, non-neoplastic lesion most commonly seen in the metaphyses of the long bones in children. While rare, the NOF has been reported in the mandible. The NOF in the extra-gnathic skeleton has a characteristic radiographic appearance, is typically asymptomatic and has a variable histologic make-up. Correlation of the radiographic appearance, clinical presentation and histopathology allows for differentiation of the NOF from odontogenic and non-odontogenic cysts and tumors. We report a new case of this interesting entity and review the radiographic, clinical and histologic features of the gnathic NOF reported in the literature. A thorough search of the English language literature returned a total of 19 cases of NOF involving the gnathic bones.

Melanotic neuroectodermal tumor of infancy

Melanotic neuroectodermal tumor of infancy (MNTI) is an uncommon lesion with remarkably consistent histopathologic features that arises primarily in the pediatric population. We describe a MNTI arising in the anterior maxilla of a 6-month-old boy.

Keratinization-associated miR-7 and miR-21 regulate tumor suppressor reversion-inducing cysteine-rich protein with kazal motifs (RECK) in oral cancer

MicroRNAs (miRNAs) are small non-coding RNAs that posttranscriptionally regulate gene expression during many biological processes. Recently, the aberrant expressions of miRNAs have become a major focus in cancer research. The purpose of this study was to identify deregulated miRNAs in oral cancer and further focus on specific miRNAs that were related to patient survival. Here, we report that miRNA expression profiling provided more precise information when oral squamous cell carcinomas were subcategorized on the basis of clinicopathological parameters (tumor primary site, histological subtype, tumor stage, and HPV16 status). An innovative radar chart analysis method was developed to depict subcategories of cancers taking into consideration the expression patterns of multiple miRNAs combined with the clinicopathological parameters. Keratinization of tumors and the high expression of miR-21 were the major factors related to the poor prognosis of patients. Interestingly, a majority of the keratinized tumors expressed high levels of miR-21. Further investigations demonstrated the regulation of the tumor suppressor gene reversion-inducing cysteine-rich protein with kazal motifs (RECK) by two keratinization-associated miRNAs, miR-7 and miR-21. Transfection of miR-7 and miR-21-mimics reduced the expression of RECK through direct miRNA-mediated regulation, and these miRNAs were inversely correlated with RECK in CAL 27 orthotopic xenograft tumors. Furthermore, a similar inverse correlation was demonstrated in CAL 27 cells treated in vitro by different external stimuli such as trypsinization, cell density, and serum concentration. Taken together, our data show that keratinization is associated with poor prognosis of oral cancer patients and keratinization-associated miRNAs mediate deregulation of RECK which may contribute to the aggressiveness of tumors.