Intraosseous salivary tissue: jawbone examples of choristomas, hamartomas, embryonic rests, and inflammatory entrapment: another histogenetic source for intraosseous adenocarcinoma

First report-parotid tissue choristomas within and adjacent to TMJ ligaments

PURPOSE

To report the first examples of ectopic salivary glands of TMJ ligaments & capsules.

METHODS AND MATERIALS

Nine subjects with chronic TMJ disorders were found incidentally to have ectopic salivary glands (choristomas) within or near damaged TMJ ligaments and capsules. Clinicopathologic characteristics of 12 TMJs are summarized.

RESULTS

The 9 subjects were ages 22-64 years (average = 43.0); 6 were female. Microscopic examination revealed major, almost complete ligament replacement by dense, avascular fibrous scar tissue in all but 1 sample. Chronic inflammatory cells were present in the stroma of 3 samples. A total of 33 lobular, independent salivary structures of variable sizes were embedded in or near ligaments and/or capsules. Half were multiple in the same joint; 13 were bilaterally located in the joints of a single subject, with 8 small glandular lobules in one TMJ. All glands consisted of histologically normal serous acini except 1 which showed a focal lobule of mucus acini and another comprised only of mucus acini. Serial sections showed no connection to parotid glands. Some choristomas showed the aging phenomena of fatty infiltrates (n = 7) and oncocytosis (n = 7). Additionally, 3 of the 12 TMJ samples contained preauricular lymph nodes, with 3 nodes in 1 joint and bilateral involvement in 1 subject. Of the 5 identified nodes, all but one was hyperplastic, with nonspecific inflammatory histiocytosis.

CONCLUSIONS

We report, for the first time, independent salivary gland choristomas (n = 33) within the soft tissues of the TMJ (n = 12), with one joint containing 8 such choristomas. All consisted of normal serous tissue except one, a mucus gland. Additionally, a fourth of TMJ surgical samples contained hyperplastic preauricular lymph nodes.

Assessment of MUC5AC and MUC2 Immunoexpression in Glandular Odontogenic Cysts, Dentigerous Cysts, and Mucoepidermoid Carcinomas

Glandular odontogenic cysts (GOCs) and dentigerous cysts may show mucous metaplasia. Central mucoepidermoid carcinoma is very rare and mostly associated with dental cysts. It is hypothesized that odontogenic cysts showing mucus differentiation in their lining, have a propensity to transform into MEC. The present study is the first attempt to explore the relationship between odontogenic cysts [GOCs and dentigerous cysts with mucus metaplasia (DCMM)] and MEC by evaluating immunoexpression of MUC5AC and MUC2. Immunoexpression of MUC5AC and MUC2 was evaluated semiquantitatively in GOCs (20 cases), DCMMs (20 cases), and MECs (20 cases). The percentage of positive cells, intensity, and localization of immunoexpression were assessed for each marker in all cases. Of GOCs, DCMMs, and MECs cases, 85%, 70%, and 80%, respectively, were immunopositive for MUC5AC. Strong cytoplasmic immunoreactivity for MUC5AC was noted, particularly in mucous cells present diffusely within MECs. However, the immunoreactivity was limited to the epithelial lining of GOCs and DCMMs. Most of the MECs (60%) showed more than 25% positivity for MUC5AC, followed by GOCs, and the least in DMMCs. Mild cytoplasmic and nuclear positivity of MUC2 was noted only in epithelial lining cells of 70% GOCs and 45% DCMMs. Whereas, 55% of MECs displayed moderate to strong cytoplasmic and membranous immunopositivity for MUC2 exclusively within mucous cells. As MECs showed strong MUC5AC immunoreactivity in mucous cells, immunoexpression of MUC5AC in odontogenic cysts with mucus cells can possibly explain the pathogenesis of MEC from cysts. However, the variable expression of MUC2 did not give any strong evidence regarding its role as a marker.

Central Pleomorphic Adenoma of Mandible Mimicking Ameloblastoma - A Rare Case Report

Salivary gland neoplasms account for 3% of all head and neck tumours. Pleomorphic adenoma (PA) is the most common salivary gland tumour that mainly occurs in the parotid gland, followed by minor salivary glands of the oral cavity, however, the occurrence of PA inside the jaw bones is exceedingly rare and very few cases have been reported in the literature. Inside jaw bones these lesions tend to imitate large osteolytic lesions encompass a diagnostic challenge. An exhaustive review of the literature revealed only 10 cases of central pleomorphic adenoma. We present a rare case of primary PA that occurred inside the mandible and was provisionally diagnosed as ameloblastoma.

Central Mucoepidermoid Carcinoma Radiographically Mimicking an Odontogenic Lesion

Central mucoepidermoid carcinoma (CMEC) is a rare pathological entity with only a few case reports in the literature. The present case reported an uncommon occurrence of CMEC mimicking an odontogenic lesion in a young patient. A 17-year-old female patient sought dental care due to a slight swelling located in the posterior region of the mandible on the left side. Radiographic exams revealed an osteolytic lesion with defined limits in relation to proximity to the pericoronal follicle of tooth #38. The clinical and radiographic diagnostic hypothesis was an odontogenic lesion. Histological sections showed the presence of a neoplasm of glandular origin, not encapsulated, with a predominantly cystic growth pattern. The neoplasm consisted of mucous, intermediate, and squamous cells. In the immunohistochemical staining, the neoplastic cells were positive for cytokeratin 7. Mucous cells were positive for PAS with diastase digestion. The final diagnosis consisted of mucoepidermoid carcinoma. The tumor was removed surgically, and the patient has shown no signs of relapse nor recurrence. In conclusion, CMEC may mimic radiographic features of various pathologies, but despite its rarity, clinicians and oral radiologists should consider CMEC as a diagnostic hypothesis for jaw lesions.

Intraosseous mucoepidermoid carcinoma of the mandible

Background

Mucoepidermoid carcinoma starts in the salivary glands and accounts for 5%-10% of all salivary gland tumours. Its intraosseous occurrence is rare and only accounts for 2%-3% of all mucoepidermoid carcinomas. This neoplasm often follows a long and indolent course. Also, given its ambiguous presentation and similarities to other dental pathologies, it often has a late diagnosis. In this instance, we present the case of a patient with an asymptomatic mandibular lesion, who underwent mandibular resection and reconstruction with fibula free flap.

Case report

A 32-year-old male patient reported discomfort when chewing, which was attributable to a self-detected mass localised in proximity to teeth 47 and 48. The lesion presented as a slight swelling without clear expression in the oral cavity mucosa. The rest of the physical examination revealed no abnormalities. Both the panoramic radiograph and computed tomography of the maxillary bones revealed lytic lesions in proximity to teeth 47 and 48, close to the mandibular angle. An incisional biopsy was performed, for which the pathological anatomy showed low-grade mucoepidermoid carcinoma. A resection was then performed, which involved a right hemimandibulectomy with ipsilateral cervical lymphadenectomy. The reconstruction was performed with a right fibula-free flap. Upon histological evaluation of the surgical specimen, an intermediate-grade mucoepidermoid carcinoma was found. The patient presented good post-operative evolution. Following a multidisciplinary assessment, the use of adjuvant radiation therapy was deemed necessary. The patient currently presents good evolution and has regular check-ups.

Conclusion

Intraosseous mucoepidermoid carcinoma is a rare salivary gland tumour. Given its low frequency, there are no studies that accurately describe its biological behaviour and prognosis.

The prevalence of Stafne bone cavity: A meta-analysis of 355,890 individuals

Background/purpose

A Stafne bone cavity (SBC) is an incidental depression in the lingual surface of the mandible. The aim of this study is to provide pooled estimates of the frequency of Stafne bone cavity and to correlate its presence with such variables as sex, laterality, diagnostic methods and population.

Materials and methods

Potential studies were searched through four electronic databases: Google Scholar, PubMed, Scopus, and Journal Storage. Titles, abstracts, and full texts of the articles were screened.

Results

A total of 54 studies relating to 355,890 subjects met the inclusion criteria for meta-analysis. A meta-analysis using the DerSimonian-Laird model revealed an overall prevalence of 0.17% (CI:0.14%-0.21%, I ² = 80.7%). SBC was four times more common in males than females (z = 6.94, P < 0.01), and was unilateral in almost all cases (z = 12.90, P < 0.01). Radiographic studies yielded a lower SBC prevalence at 0.12% (CI:0.09%-0.15%, I ² = 71.7%) than computed tomography studies, skeletal studies and excavation studies. Ancient populations had three times higher SBC prevalences (0.47%, CI:0.21%-0.73%, I ² = 89.5%) than the average populations today (z = 3.21, P < 0.01).

Conclusion

The prevalence of Stafne bone cavity is approximately 0.17%, and was four times more prevalent in males than females. This variant bone cavity was also present unilaterally in the majority of cases. Awareness of SBC is important for dentists, maxillofacial surgeons and other practitioners performing routine dental practices and interpreting panoramic radiographs.

Central mucoepidermoid carcinoma of the mandible deriving from odontogenic cyst: A case report and review of the literature

Mucoepidermoid Carcinoma (MEC) it can origin from a mandibular odontogenic cyst. We report the case of a 63-year-old man with MEC of the right retromolar trigonum of the mandibula. We performed a wide mandibular excision and immediate reconstruction with a fibula bone free flap.

Retrospective analysis of primary intraosseous malignancies in mandible and maxilla in a population of Taiwanese patients

BACKGROUND/PURPOSE

Due to the rarity and diversity of primary intraosseous malignancies in jawbones, we aimed to evaluate the clinicopathological features and discuss the findings of our collected cases with the literatures.

METHODS

Twenty-nine patients (2000-2020) diagnosed with primary central malignancies of jawbones were selected from the database of Oral Pathology Department in our institution. Clinical features, radiographic appearance, and histopathological diagnosis of the 29 cases were analyzed.

RESULTS

Twenty-nine patients aged between 19 and 84 years (average, 57.4 years) with a male to female ratio of 1.2:1 were included. The most frequent site was the mandibular body and ramus, followed by the posterior maxilla and mandibular symphysis. The most common diagnosis was osteogenic sarcoma (n = 13), followed by odontogenic carcinoma (n = 7), hematologic malignancies (n = 5), salivary gland malignancies (n = 2), and neurogenic sarcomas (n = 2). The most frequent symptoms were swelling, pain, paresthesia of lower lip, and mobile tooth. Radiographically, they usually presented as ill-defined osteolytic to osteoblastic lesions depending on the amount of ossification. Wide excision comprising partial maxillectomy and segmental mandibulectomy were the most common therapeutic methods.

CONCLUSION

Despite the rarity of primary central malignancies in jawbones, the clinical features may mimic infectious process or benign lesions. Detailed history-taking, clinical and imaging examination and awareness of the patient's signs and symptoms combining with the histopathological inspection are important for early diagnosis and improved prognosis. The current data contributes a useful basis for clinical investigation regarding intraosseous malignancies occurring in the jawbones.

An Unusual Maxillary Tumor with Tubuloductal Epithelial Structures, Solid Epithelial Nests and Stromal Odontogenic Ameloblast-Associated Protein Deposits. Tubuloductal/Syringoid Variant of Central Odontogenic Fibroma with Amyloid?

Glandular tumors of jaw bones present, most often, histopathologic features of salivary gland and, rarely, of cutaneous glandular neoplasms. They are thought to originate from odontogenic epithelium. An unusual maxillary tumor presenting as a radiolucency in the periapical area of the right permanent lateral incisor of a 74-year-old male is presented causing root resorption. Preparations revealed occasionally branching tubular cords and ductal structures characterized, mostly, by a bilayer composed of luminal cuboidal to low columnar cytokeratin (CK) 7, Ber-EP4 and occasionally CK8/18 positive cells, and abluminal, CK5/6 positive, basal/basaloid cells revealing nuclear reactivity for p63/p40. Smooth muscle actin and calponin were negative, save for a single focus of calponin positive cells, confirming absence of myoepithelial support or epithelial mesenchymal transition. CK19 exhibited staining of both layers, the luminal being more intense. Eosinophilic secretory material and, occasionally, a luminal pellicle were decorated with CK8/18 and polyclonal carcinoembryonic antigen (CEA). CD1a identified only rare Langerhans' cells and Ki67 decorated 1-2% of abluminal cell nuclei. Small solid nests of epithelial cells were also present. Infrequently, an apparent transition of a nest into a tubular structure was appreciated. The partially inflamed stroma featured multiple hyalinized acellular deposits consistent with amyloid, as confirmed by bright orange Congo red reactivity with apple-green birefringence, which reacted with odontogenic ameloblast-associated (ODAM) protein antibody but not with antibodies for amelotin and secretory calcium-binding phosphoprotein proline-glutamine rich 1. Based on the above, the diagnosis of tubuloductal/syringoid variant of central odontogenic fibroma with ODAM amyloid is favored.

Imaging of Malignant Minor Salivary Gland Tumors of the Head and Neck

Minor salivary gland carcinomas (MSGCs) are nonminor tumors in the head and neck region and account for about half of all salivary gland carcinomas. Imaging evaluation based on the anatomy of minor salivary and mucous glands in the head and neck region as well as invasion patterns in each site helps in identifying optimal treatment modalities and planning suitable treatment strategies. MSGCs can be divided radiologically into localized and invasive subtypes on the basis of the clinical utility of such categorization. Characteristic invasion patterns of the invasive type include deep submucosal extension, bone marrow infiltration, and perineural spread, which are difficult to assess clinically. MSGCs easily invade adjacent structures because of their submucosal location and may spread along the muscles, nerves, periosteum, and dura mater. Moreover, the tumor may spread into the bone marrow without obvious bone destruction. In addition to imaging classification, examining the anatomy and distribution of the minor salivary glands, including the palatal, lingual, buccal, labial, and retromolar glands, as well as other mucous glands, including the glands of the sinonasal cavity and nasopharynx, lacrimal glands, ceruminous glands, laryngeal glands, and tracheal glands, facilitates MSGC diagnosis and tumor extension assessment. The authors review the precise anatomy of the minor salivary and mucous glands in the head and neck region, discuss the MSGC imaging classifications, and describe how to evaluate the extent of MSGCs in each site on the basis of the imaging classification and invasion patterns. ^©RSNA, 2020.

Six cases of central cystadenocarcinoma and review of relevant papers

The present study was a review of cases of central cystadenocarcinoma over the past 29 years and provides clinical, radiological, and pathological information about these rare lesions. Six cases of central cystadenocarcinoma treated between 1991 and 2019 at Peking University Hospital of Stomatology in Beijing, China, were retrospectively analysed. A comprehensive review of clinical records was summarised and the histological diagnosis was revised using the 2017 World Health Organization criteria. The mean age of patients with central cystadenocarcinoma was 63 (range 51-75) years, and the male:female ratio 1:1. The clinical signs included localised swelling, pain, lower lip numbness, and trismus. There were more cases in the mandible than in the maxilla. All lesions were unilocular or multilocular in radiolucent regions with or without clear margins. The preferred treatment of central cystadenocarcinoma was surgical excision with wide margins, and no local recurrence was found during follow-up. Central cystadenocarcinoma often occurred in middle-aged or elderly patients. Because cystadenocarcinoma is somewhat rare, metastatic tumours of the jaw should be considered when diagnosing cystadenocarcinoma.

Diagnosis and treatment for central Mucoepidermoid Carcinoma in the mandible: Report of a clinical case in a young patient

A clinical case of a 13 year old male patient with a malignant tumor in the mandibular body area with two years of evolution and associated pain is reported. It was initially diagnosed as low grade central mucoepidermoid carcinoma through Hematoxylin and Eosin (H-E) staining in multiple biopsies. Considering the clinical and radiographic characteristics of the lesion, it was necessary to confirm the diagnosis through Periodic acid-Schiff (PAS). The treatment involved hemimandibulectomy, neck emptying, and complementary radiotherapy. This article aims to present a rare occurrence of this type of intraosseous malignant tumor of glandular origin in a young patient.

Key words:Mucoepidermoid carcinoma, periodic acid Schiff reaction, pathology, surgery, radiotherapy.

Middle ear choristoma presenting as cholesteatoma with conductive hearing loss

A 6-year-old male was seen for evaluation of middle ear polyp with associated hearing loss and otorrhea. CT scan revealed canal polyp with a stalk extending to the middle ear with malformation of the malleus and incus. The patient underwent exploratory tympanotomy which revealed a fistula from the bony-cartilaginous junction connecting to a middle ear mass which had eroded the incus. Intraoperative pathology suggested columnar epithelium without cholesteatoma or muscle. Final pathologic diagnosis reported dense fibrous tissue as well as ectopic salivary gland tissue, consistent with salivary gland choristoma. After removal of the mass, a partial prosthesis was successfully placed. Middle ear salivary gland choristoma is a rare entity. It can be confused clinically with cholesteatoma and is usually diagnosed on pathology. This diagnosis is often associated with other external, middle, and inner ear abnormalities.

Central mucoepidermoid carcinoma: Case report with review of literature

Occurrence of central mucoepidermoid carcinoma within the jaw bones from aberrant salivary tissues is extremely rare and accounts for 2%-4% of all central mucoepidermoid carcinoma. Mandible is more commonly affected than maxilla in a ratio of 2:1. The origin of mucoepidermoid carcinoma is controversial and questionable. Central mucoepidermoid carcinoma is frequently misdiagnosed radiographically and clinically as a benign odontogenic tumor or cyst. Hence, it is important to detect malignant signs and histopathological feature of central mucoepidermoid carcinoma of the mandible to confirm the diagnosis. This paper reports a case of central mucoepidermoid carcinoma of the mandible in a 56-year-old patient with review of literature.

Intraosseous Mucoepidermoid Carcinoma in the Mandible

Although it is a rare neoplasm, intraosseous mucoepidermoid carcinoma is the most common and well-recognized intraosseous salivary gland tumor. Usually, it presents as an asymptomatic volume increase and most patients perceive the presence of the lesion within a year or less of evolution. They are more common in middle-aged adults and have a slight female predilection. They are three times more common in the mandible than in the maxilla and are most often found in the area of the molars and mandibular ramus. The most frequently present symptom is cortical bulging, although some lesions may be discovered as an accidental finding on radiographs. The main modality of treatment for patients with this neoplasm is radical surgical resection, offering a greater chance of cure than the more conservative procedures, such as enucleation or curettage, due to the great possibility of recurrence and tumor metastasis. This paper reports a rare case of intraosseous mucoepidermoid carcinoma occasionally discovered after panoramic radiography of the jaws, which was treated with segmental resection through hemimandibulectomy.

Metastasizing Pleomorphic Adenoma Case Report and Review of the Literature

Pleomorphic adenoma (PA) is by far the most common salivary gland tumor. It is well known that PA can undergo malignant transformation. However, in rare occasions it can metastasize preserving its benign phenotype. Metastasizing pleomorphic adenoma (MPA) constitutes an extremely rare tumor. Here we are reporting an unusual MPA affecting the mandible that was preceded by a submandibular gland pleomorphic adenoma.

Establishment and characterization of a clear cell odontogenic carcinoma cell line with EWSR1-ATF1 fusion gene

OBJECTIVE

Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumor (MOT) characterized by sheets and lobules of vacuolated and clear cells. To understand the biology of CCOC, we established a new cell line, CCOC-T, with EWSR1-ATF1 fusion gene from a mandible tumor with distant metastasis and characterized this cell line.

MATERIALS AND METHODS

To detect the EWSR1-ATF1 fusion gene, we used three CCOC cases, including the present case, by RT-PCR and FISH analysis. We characterized established CCOC-T cells by checking cell growth, invasion and the expression of odontogenic factors and bone-related factors. Moreover, the gene expression profile of CCOC-T cells was examined by microarray analysis.

RESULTS

Histologically, the primary tumor was comprised of cords and nests containing clear and squamoid cells separated by fibrous septa. In addition, ameloblastomatous islands with palisaded peripheral cells were observed, indicating probable odontogenic origin. This tumor expressed the fusion gene EWSR1-ATF1, which underlies the etiology of hyalinizing clear cell carcinoma (HCCC) and potentially that of CCOC. We found a breakpoint in the EWSR1-ATF1 fusion to be the same as that reported in HCCC. Established CCOC-T cells grew extremely slowly, but the cells showed highly invasive activity. Moreover, CCOC-T cells expressed bone-related molecules, odontogenic factors, and epithelial mesenchymal transition (EMT)-related molecules.

CONCLUSION

To the best of our knowledge, this is the first report on the establishment of a CCOC cell line. CCOC-T cells serve as a useful in vitro model for understanding the pathogenesis and nature of MOT.

Extensive Regional Metastasis of High-Grade Mucoepidermoid Carcinoma of an Unknown Primary Tumor

PURPOSE

Mucoepidermoid carcinoma (MEC) is the most common salivary carcinoma. It arises most frequently in the major salivary glands, but can also arise in minor glands or intraosseous sites. MEC of an unknown primary occurs very rarely. The present report documents only the third case reported in medical studies.

METHODS

A 66-year-old man with previous carcinoma in situ (CIS) of the left posterior oral tongue that had been excised in 2004 and again in 2010 presented with a hard lymph node, 3 × 2 cm at level II of the right neck in July 2015. Positron emission tomography-computed tomography (PET-CT) revealed multiple, bilateral cervical lymphadenopathy, with no primary site identified. Fine needle aspiration biopsy and cytologic examination from the right neck was positive for malignancy, suggestive of metastatic squamous cell carcinoma. Panendoscopy and biopsy revealed CIS at the tongue bases and tonsils bilaterally (p16-negative). The patient's case was presented to a tumor board, and definitive concurrent cispl.atin-based chemoradiation was recommended for TisN2cM0, stage IVA oropharyngeal CIS, which was completed in November 2015. PET-CT in January 2015 showed complex interval changes, with some areas demonstrating improvement (ie, no uptake in the left neck) and worsening in others (ie, increased metabolic activity in the right neck), suggestive of residual disease. Repeat PET-CT in March 2016 showed increased nodal involvement and increasing standardized uptake value. Bilateral modified radical neck dissection was undertaken, and histologic examination showed high-grade MEC in 51 of 61 lymph nodes with extracapsular spread and soft tissue involvement.

RESULTS

The patient died in May 2016 at 2 months after surgery.

CONCLUSIONS

Metastatic MEC of an unknown primary is a diagnostic challenge. PET-CT might not be the most reliable diagnostic investigation to identify the primary or metastatic foci, such as was demonstrated in the present case.

Stafne bone cavity with ectopic salivary gland tissue in the anterior of mandible

Stafne bone cavities (SBCs) are uncommon well-demarcated defects of the mandible, which often occur in the posterior portion of the jaw bone and are usually asymptomatic. Furthermore, SBC is found in men aged 50–70-year-old. Anterior mandibular variants of SBC are very rare. This article describes a case of anterior SBC in a 45-year-old man that resembled endodontic periapical lesions. Upon histopathological examination, it turned out to be a normal salivary gland tissue.

Primary intraosseous mucoepidermoid carcinoma of maxilla

Primary intraosseous mucoepidermoid carcinoma (PIOC) of the jaw bones is an extremely rare malignant salivary gland tumor, comprising 2–3% of all mucoepidermoid carcinomas reported. It is commonly seen in the posterior part of the mandible; its occurrence in the maxilla is rare. They have been reported in patients of all ages, ranging from 1 to 78 years, with the overwhelming majority occurring in the 4th and 5th decades of life. They are histologically low-grade cancers and radiographically seen as uniocular or multiocular lesions. We report a rare case of PIOC in posterior palatal region in 18-year-old male.

Molecular and genetic aspects of odontogenic lesions

In this article we outline the molecular findings of select odontogenic tumors. In each section, we briefly review selected the clinicoradiographic, histologic, immunologic features, focusing on the molecular findings and their applications in practice. The understanding of molecular pathobiology at various other organ sites has developed quite rapidly in recent years, however much remains unknown about the genetic profile of odontogenic tumors. Improved understanding of mutations in odontogenic tumors may clarify classification schema and elucidate targets for novel therapies. Molecular testing will no doubt improve our understanding of odontogenic tumor pathogenesis and will likely be, someday, an important component of routine clinical practice and its role will only increase in the coming years.

Stafne bone defect in the anterior mandible

Lingual mandibular bone defect, also known as Stafne bone cavity, is mostly seen in the posterior portion of the mandible. Cavities in the anterior region are very unusual, with around 50 cases reported in the English literature. They are often asymptomatic and found during routine radiographic examinations. This article describes a case of anterior Stafne bone cavity in a 56-year-old male patient.

Central papillary cystadenocarcinoma of the mandible: A case report and review of the literature

INTRODUCTION

Central papillary cystadenocarcinoma of the jaw is an extremely rare tumor with only three previously reported cases in the English literature. This tumor is a histologically low-grade cancer, affecting more commonly in the mandible than in the maxilla.

PRESENTATION OF CASE

A 65-year-old woman presented with a two months history of a rapidly growing, painless mass of the right ascending ramus of the mandible. The pathologic report from incisional biopsy was a papillary cystic tumor with a differential diagnosis of cystadenoma versus cystadenocarcinoma. Segmental mandibulectomy, parotidectomy and submandibular gland resection were performed. The final pathology was intraosseous papillary cystadenocarcinoma.

DISCUSSION

Clinical features of central papillary cystadenocarcinoma of the mandible mimic an odontogenic lesion and metastatic bone disease, careful review of radiograph and pathology should be done. Surgical excision with wide margins is the appropriate treatment. Postoperative radiation therapy should be considered in histologically aggressive or high-stage tumor.

CONCLUSION

This is the fourth case of central papillary cystadenocarcinoma of the mandible in the English literature. Although it is usually a low-grade cancer, en bloc resection with adjuvant postoperative radiotherapy in a high-stage disease, and long-term follow-up allow the patient to have a favorable prognosis.

Introduction to Through-Transmission Alveolar Ultrasonography (TAU) in Dental Medicine

Through-transmission alveolar ultrasonography (TAU) is a novel imaging modality in dental medicine. A brief introduction to through-transmission ultrasonography (TTU) is followed by a description of the first commercially available TAU device, the Cavitat CAV 4000 (Cavitat Medical Technologies, Inc., Alba, TX). Recent associations between systemic osteoporosis, oral osteoporosis, periodontal diseases, and cardiovascular diseases underline the importance of early detection and treatment of oral cancellous bone pathologies associated with low bone density (LBD), such as regional ischemic osteoporosis, chronic nonsuppurative osteomyelitis, bone marrow edema, and cavitational ischemic osteonecrosis (osteocavitation). While the impact of osteoporosis on maxillofacial bones is acknowledged, there is a lack of reliable prevalence rate, and the National Institutes of Health (NIH) recommend that more attention should be paid to skeletal health, especially in persons with conditions known to be associated with secondary osteoporosis. TAU, a safe and effective imaging modality, can be a valuable tool in research as well as for the clinical assessment of alveolar cancellous bone pathologies associated with LBD and ischemia.

Giant cystic primary mucoepidermoid carcinoma of mandible: a rare case and literature review

Primary intra-osseous mucoepidermoid carcinoma arising from jaw is an extremely rare condition accounting to less than 2% of all mucoepidermoid carcinomas. In the jaw, it occurs more commonly in mandible than maxilla. They are low-grade cancers and affect jaw as uni- or multi-locular radiographic lesions. Here we discuss a rare case of giant cystic primary intra-cystic mucoepidermoid carcinoma of the mandible which was excised in toto. Here we discuss the clinical features, radiological and histological characteristics of this rare lesion, and review the literature.

Predominantly cystic central mucoepidermoid carcinoma developing from a previously diagnosed dentigerous cyst: case report and review of the literature

Primary intraosseous mucoepidermoid carcinoma of the jawbones is an extremely rare malignant salivary gland tumour constituting 2-4.3% of all the reported mucoepidermoid carcinomas. We report a case of intraosseous mucoepidermoid carcinoma of the mandible in an 80-year old female patient developing from a previously diagnosed dentigerous cyst. An excisional biopsy was performed and the histopathological features confirmed low grade-cystic intraosseous mucoepidermoid carcinoma. The origin of central mucoepidermoid carcinoma could be suggested to be from the epithelial lining of previously diagnosed dentigerous cyst. Thus, emphasizing the need for careful examination of the entire excision specimen to rule out such neoplastic transformation of epithelial lining of odontogenic cyst and provide appropriate and effective treatment.

Heterotopic salivary gland tissue: A report of two cases

The heterotopic salivary gland or salivary choristoma is defined as a tumor - like growth of otherwise normal salivary gland found in an abnormal location. In general, salivary gland tissue is not observed in the gingiva, with only isolated case reports having been found. The occurrence of the case in the midline, especially in the anterior two - thirds of the hard palate, has not been documented so far (PubMed search engine). It is apparent that these reported cases constitute a unique clinico -pathologic entity. Clinically, they appear as soft tissue tumors and are composed of lobules of salivary gland tissue.

Intraosseous mucoepidermoid carcinoma of jaws: report of 24 cases

OBJECTIVE

Intraosseous mucoepidermoid carcinoma of jaws is rare, and management of the disease remains poorly understood. The aim of this study was to assist the diagnosis and treatment of the tumor.

STUDY DESIGN

The records of clinical data and follow-up information were collected from 1996 to 2010 and retrospectively analyzed for clinical features, surgical intervention, and prognosis.

RESULTS

Of 24 cases, 15 were male, and the average age was 47.33 years. The clinical presentation of this tumor varied. For primary lesions and neck nodes, radical surgery was performed; radiotherapy or chemotherapy was administered after operation. The survival rate of all patients was 66.7%. The average survival period was 53.3 months after surgery.

CONCLUSIONS

Diagnosis should be based on clinical and pathologic manifestations, surgery is the first choice for patient treatment, and radiotherapy may improve prognosis and therefore should be recommended in postoperative period.

Intraosseous carcinoma of the jaws--a clinicopathologic review. Part I: Metastatic and salivary-type carcinomas

This is the first part of a 3-part comprehensive review of intraosseous carcinoma of the jaws. We have outlined 4 groups of intraosseous carcinoma of the jaws (metastatic, salivary-type, odontogenic, and primary intraosseous carcinoma), emphasizing the need for accurate diagnosis and the problems associated with changing classification systems, standardization of diagnostic criteria and nomenclature, and the accuracy of existing literature. In this first part, the features of metastatic and the very rare salivary-type carcinomas of the jaws are examined with particular emphasis on histologic and immunohistochemical characteristics, diagnostic difficulties, and uncertainties.

Central mucoepidermoid carcinoma: a clinicopathologic and immunohistochemical study of 39 Chinese patients

Central mucoepidermoid carcinoma (MEC) is a rare neoplasm arising intraosseously in the jaws. To clarify the clinicopathologic profile and pathogenesis of central MEC, clinicopathologic findings and follow-up data of 39 cases were collected and analyzed. There were 16 male and 23 female patients (median age, 43 y). Sixteen cases affected the maxilla, and 23 occurred in the mandible. Radiographically, most cases (32 of 39) showed a unilocular or multilocular radiolucency with bone destruction, and 7 were found with scattered calcification. The margins of the lesions were ill defined or diffused in 14 cases and relatively well defined in 25 cases. Most cases (26 of 39) were classified as low-grade MECs, whereas 13 were moderate-to-high grade. Follow-up data were available for 35 patients with a median period of 36 months. All cases were found to be primary; local recurrence occurred in 8 cases, most (75.0%) of which were low-grade tumors. Four cases showed regional lymph node metastasis, and 1 developed distant metastasis. Of 11 cases with a clinical history of the jaw cyst, 8 initially showed a typical odontogenic cyst with local MEC-like proliferation. In summary, the most likely pathogenesis of central MEC is neoplastic transformation of the epithelial lining of an odontogenic cyst, diagnosis of which should be based on clinical, radiographic, and histopathologic findings. The immunohistochemical profile of keratins is helpful in differential diagnosis. Radical surgery is the treatment of choice, whereas the role of radiotherapy or chemotherapy is still controversial, and careful long-term follow-up is necessary.

Central mucoepidermoid carcinoma, a case report with molecular analysis of the TORC1/MAML2 gene fusion

Mucoepidermoid carcinoma is the most common salivary gland malignancy. The majorities of these tumors arise in the parotid and minor salivary glands, but may rarely develop intraosseously. The latter is not uncommonly associated with diagnostic and management difficulties. We report an example of intraosseous mucoepidermoid carcinoma with positive TORC1/MAML2 gene fusion transcript and discuss the clinical implications.

Is maspin immunolocalization a tool to differentiate central low-grade mucoepidermoid carcinoma from glandular odontogenic cyst?

Mucoepidermoid carcinoma (MEC) of the salivary glands has a low-grade variant (LGMEC), which may be found within the jawbones. LGMEC shares a number of histopathological similarities with glandular odontogenic cysts (GOC) of the jawbones. Maspin has been identified in several benign and malignant salivary gland neoplasms. We investigated the immunolocalization of maspin in LGMEC and GOC and evaluated its potential to distinguish between these two entities. Cases of LGMEC (n=6), GOC (n=8) and various odontogenic cysts with marked mucous metaplasia (OCMM, n=7), which served as controls, were immunohistochemically labeled for the binding of an antibody directed against maspin. Immunomorphometry was performed separately for maspin-immunopositive epithelial cells and epithelial-mucous cells in either their nuclear or cytoplasmic compartments. Results were presented as the volume fraction (Vv) of each element. The Vv of the maspin-immunopositive epithelial-mucous cytoplasm and nuclei was significantly higher in LGMEC than in GOC and OCMM (p<0.001 and p=0.026, respectively). In the epithelial cells, no significant differences were observed among the lesions (p>0.05). It is suggested that the high levels of maspin in the epithelial-mucous cells (in both cytoplasm and nuclei) in LGMEC may serve as a tool to distinguish it from GOC. This may be useful especially in equivocal cases and in small incisional biopsy samples.