Ossifying fibromyxoid tumor of the oral cavity: rare case report and long-term follow-up

Ossifying fibromyxoid tumor (OFMT) is a rare mesenchymal soft tissue benign neoplasm with an uncertain line of differentiation, which arises most frequently in extremities. The head and neck region involvement is uncommon, with only ten intraoral cases published in the English-language literature. One additional case of OFMT is reported here, including a literature review of intraoral reported cases. A 45-year-old female patient presented a painless nodule involving the buccal mucosa of approximately two years duration, measuring nearly 1.3 cm in maximum diameter. The main histopathological features include ovoid to round cells embedded in a fibromyxoid matrix with a perpheral shell of lamellar bone. Immunohistochemically, the tumor showed immunoreactivity for vimentin and S100. No recurrence has been detected after 7 years of follow-up

Peripheral desmoplastic ameloblastoma: Histopathological and immunohistochemical profile of a case

In this study we present a rare case of peripheral desmoplastic ameloblastoma and discuss its clinical features, histopathology, and inmunoshistochemical profile. This article reports a new case of this unusual neoplasm in a 66 year-old woman in which the main complaint was an asymptomatic swelling located in the right body of mandible. Histopathological findings were similar to the two previously reported cases of this tumor. Positive immunohistochemical stain for laminin V and type IV collagen suggests an inductive effect of the epithelium over the stroma while the low index of p53 protein and Ki-67 expression in epithelium and stromal cells, as well as CD138 uniform positive-stain in epithelial cells, support the benign biological behavior of this lesion. Including this new case, currently there are only three reports of this rare neoplasm. Reports of new cases of peripheral desmoplastic ameloblastoma are necessary for a better understanding of the origin and behavior of this particular subtype of ameloblastoma.156E846E84

Oral Verruciform Xanthoma: A Clinicopathologic And Immunohistochemical Study Of 20 Cases.

Verruciform xanthoma of the oral cavity is an uncommon benign lesion that usually affects the palate and gingiva mainly as a well-circumscribed solitary yellowish to whitish plaque or nodule, which is promptly recognized microscopically by identification of sub-epithelial foamy macrophages. The aim of this study was to evaluate the clinicopathologic and immunohistochemical features of 20 cases of oral verruciform xanthoma. All cases were evaluated by conventional hematoxylin/eosin staining and six of those were submitted to immunohistochemical reactions for CD68, CD63, CD163, syndecan-1 (CD138), S-100 protein and cytokeratins (CK) 8, 14 and 19. Oral verruciform xanthoma presented as yellowish papillary nodules affecting mainly the palate (30%), buccal mucosa (30%) and gingiva (25%) of middle-aged male patients. Most cases presented papillary epithelial hyperplasia and sub-epithelial foamy cells, which were immunopositive for CD68, CD63 and CD163 in all cases. The orange parakeratin superficial layer was negative for CK14 and presented a distinct granular membrane pattern of positivity for CD138. S-100 protein, CK8, and CK19 were negative.42489-49

Mass spectrometry-based proteome profile may be useful to differentiate adenoid cystic carcinoma from polymorphous adenocarcinoma of salivary glands

The aim of this study was to determine the proteome of adenoid cystic carcinoma (AdCC) and polymorphous adenocarcinoma (PAc) and to identify a protein signature useful in distinguishing these two neoplasms. Ten cases of AdCC and 10 cases of PAc were microdissected for enrichment of neoplastic tissue. The samples were submitted to liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the proteomics data were analyzed by using the MaxQuant software. LC-MS/MS spectra were searched against the Human UniProt database, and statistical analyses were performed with Perseus software. Bioinformatic analyses were performed by using discovery-based proteomic data on both tumors. LC-MS/MS analysis identified 1957 proteins. The tumors shared 1590 proteins, and 261 were exclusively identified in AdCC and 106 in PAc. Clustering analysis of the statistically significant proteins clearly separated AdCC from PAc. Protein expression 10 times higher in one group than in the other led to a signature of 16 proteins-6 upregulated in AdCC and 10 in PAc. A new clustering analysis showed reverse regulation and also differentiated both tumors. Global proteomics may be useful in discriminating these two malignant salivary neoplasms that frequently show clinical and microscopic overlaps, but additional validation studies are still necessary to determine the diagnostic potential of the protein signature obtained.1286639650FAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo2009/54067-3; 2015/16056-