Mário José Romañach

Lichen sclerosus of the oral mucosa: clinicopathological features of six cases

Lichen sclerosus is a chronic inflammatory mucocutaneous disease, rarely involving the mouth. There are only 20 well-documented cases of oral lichen sclerosus reported in the English-language literature. This report describes the clinicopathological features of 6 cases of oral lichen sclerosus; 5 in women. There were 12 lesions, mainly on the lips (50%) and buccal mucosa (25%). The affected areas appeared as irregular whitish patches, harder than the surrounding tissue. Half of the patients were symptomatic and presented with no associated skin and/or genital lesions. All cases were biopsied, and histopathological features were evaluated using hematoxylin-eosin and Verhoeffs stains, S-100 immunohistochemical reaction and transmission electron microscopy. Management of the oral lesions consisted of surgical excision, intralesional triamcinolone acetonide, oral colchicine, and regular follow-up. There is no effective curative treatment, but there are some options for patient management; and colchicine may be considered an additional choice.

Pigmented villonodular synovitis of the temporomandibular joint: case report and review of the literature

Pigmented villonodular synovitis (PVNS) is an aggressive proliferative lesion that usually involves the synovial tissues of big joints. To date, there are ∼52 cases of PVNS affecting the temporomandibular joint reported in the English-language literature, about one-third of them exhibiting intracranial involvement. We herein describe an additional case of PVNS of the temporomandibular joint with skull base invasion affecting a 26-year-old male patient and discuss its clinicopathologic features considering previously published cases. Histopathology and imaging evaluation are important for the diagnosis of PVNS, which should be included in the differential diagnosis of preauricular aggressive swellings.

Clinicopathological and immunohistochemical features of oral spindle cell carcinoma

BACKGROUND Oral spindle cell carcinoma (SpCC) is a rare variant of oral squamous cell carcinoma (SCC). The aims of this study were to compare the clinicopathologic and immunohistochemical features of oral SpCC with conventional oral SCC. METHODS Five cases of oral SpCC and 10 cases of oral SCC (five well-differentiated and five poorly differentiated) were evaluated through conventional hematoxylin and eosin staining and immunohistochemical reactions to cytokeratins (CK), vimentin, desmin, smooth muscle actin, muscle-specific actin, S-100 protein, epithelial membrane antigen (EMA), p53, and ki-67. RESULTS Oral SpCC showed predilection for males on their sixth decade of life, presenting clinically as painful infiltrative ulcers or ulcerated exophytic polypoid masses, preferably located on the alveolar mucosa. Mesenchymal markers were expressed in the spindle cell but not in the carcinomatous component of SpCC, and it was negative in all SCC. CKs AE1/AE3, 6, 14, and EMA were positive on both carcinomatous and spindle cell components of most SpCCs. These tumors also presented higher p53 and ki-67 expression and no CK 1 expression in contrast to well-differentiated SCC. CONCLUSION Oral SpCC presented a different clinical profile than conventional SCC and histopathologic features and p53 and ki-67 expression closer to poorly differentiated SCC. Besides mesenchymal markers, CK AE1/AE3, 6, 14, and EMA expression on spindle cells may be useful as an adjunct on microscopical differential diagnosis of SpCC.

Ectomesenchymal chondromyxoid tumor: histopathologic and immunohistochemical study of two cases without a chondroid component

Ectomesenchymal chondromyxoid tumor (ECT) is a rare benign neoplasm usually affecting the anterior dorsum of the tongue. Histopathologically, it is formed by spindle, round and/or polygonal cells embedded in a chondromyxoid matrix. Immunohistochemical positivity for vimentin, S‐100 protein, glial fibrillary acid protein and neuron‐specific enolase are helpful to confirm the diagnosis. There are 42 cases of ECT of the tongue reported in the English language literature, three of them showing no chondroid matrix. We describe two additional cases of ECT lacking the chondroid component, exhibiting areas of reticulated myxoid and cellular pattern. Considering the microscopical features, ECT can be classified in classic and ‘chondroid‐free’ variants, the latter including the reticulated myxoid and cellular patterns. It is important to consider that the cellular ECT usually exhibits predominance of an infiltrative atypical cellular component that may mimic a malignant tumor.

Distinctive aspects of oral hyaline ring granulomas

The hyaline ring granuloma is a distinct oral entity characterized as a foreign body reaction occurring either centrally or peripherally. The granulomas may assume different histological characteristics, possibly related to the length of time in the tissue, and adequate recognition is important to avoid misdiagnosis. The aim of this article was to report 3 cases of hyaline ring granulomas with distinctive clinical and histopathological aspects, discussing the reasons for the different histological findings.

Marginal zone lymphoma of mucosa-associated lymphoid tissue with prominent plasma cell differentiation affecting the palatine tonsil: Histopathological and immunohistochemical analysis

Non-Hodgkin lymphomas (NHLs) of the oral cavity and oropharynx constitute 13% of all primary extranodal NHLs. Marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) in the palatine tonsil is rare, corresponding to 6% of the NHLs of the Waldeyer ring. Some cases of MALT lymphoma can present prominent plasma cell differentiation, and less commonly, monoclonal gammopathy. The differential diagnosis of these cases from other NHLs with plasmacytic differentiation or plasma cell neoplasms is very difficult. In this article, we describe a rare case of MALT lymphoma in a 34-year-old man presenting as a swelling of the palatine tonsil. The tumor mass was diagnosed as MALT lymphoma with prominent plasma cell differentiation. Systemic evaluation was noncontributory. This is the first report of MALT lymphoma showing extensive plasmacytic differentiation of the palatine tonsil, and reinforces a possible relationship between extramedullary plasmacytoma and MALT lymphoma.

Clinical Pathologic Conference Case 6: Infantile Myofibroma

A 5-year-old female presented with facial asymmetry, which was first noted by her parents 1 month prior to consultation. The lesion was painful and interfered with speech and swallowing. The girl was otherwise in good health with normal physical and mental development. Her medical history was non-contributory. Extraoral examination revealed a slight facial asymmetry of the right side covered by normal-colored skin with no signs of paresthesia. Intraoral examination revealed a swelling on the buccal aspect of the right posterior mandible, covered by normal mucosa. Lingual displacement of the first molar was noted. A panoramic radiograph revealed a large well-defined multilocular radiolucent lesion measuring 4 9 3 cm, which involved the ramus and coronoid process of the right mandible, displacing dental follicles and cortical bone, but not affecting the inferior alveolar nerve canal (Fig. 1). Differential Diagnosis

Oral metastasis of alveolar soft-part sarcoma: a case report and review of literature.

Alveolar soft-part sarcoma (ASPS) is a rare malignant neoplasm with uncertain histogenesis and with a distinctive morphology. It has been described in the oral cavity, but this is the first report of ASPS metastasizing to the maxillary tuber region. A 27-year-old male patient, who was under chemotherapy treatment for ASPS of the thigh, presented in our dental clinic with a painless and pedunculated nodule on the right tuber maxillae. The nodule was erythematous with smooth and lobular surface, measuring 3 cm in maximum diameter. An incisional biopsy was performed and the diagnosis of metastatic ASPS was made. Histologically, the tumor was characterized by a proliferation of polyhedral cells in pseudoalveolar pattern. Tumor cells were large, showing granular cytoplasm, periodic acid-Schiff positive diastase-resistant intracytoplasmic material, and vesicular nuclei with prominent nucleoli. Unfortunately, the patient died 2 months after the diagnosis of the oral metastasis. Metastases of ASPS to the mouth are very rare and indicate a poor prognosis.

Mandibular unilocular well-defined radiolucency.

A 13-year-old girl was referred to the oral surgeon forassessment of a well-defined radiolucency on the rightlower first premolar roots. This asymptomatic lesion wasdetected at x-ray analysis for orthodontic planning. Theclinical examination did not show any pathologic alteration,and the related canine and first premolar had vital pulp (Fig1). Her medical history was noncontributory. A panoramicx-ray displayed an inter-radicular, well-defined, round radi-olucent lesion measuring approximately 0.8 1 cm withslightly radiopaque margins, resulting in displacement ofthese roots (Fig 2). The periapical x-ray clearly showed theperiodontal ligament space and the lamina dura on bothteeth.

Clear cell variant of calcifying epithelial odontogenic tumor: Case report with immunohistochemical findings

Calcifying epithelial odontogenic tumor (CEOT) is a rare benign odontogenic neoplasm, locally aggressive, characterized by sheets and nests of polyhedral epithelial cells exhibiting eosinophilic cytoplasm or less often clear cytoplasm. Additional features include nuclear pleomorphism without mitotic activity, concentric calcifications, and deposits of amyloid. Herein, we present an additional example of clear cell variant of CEOT occurring in a 25-year-old female. Microscopically, the tumor consisted on proliferation of epithelial cells with eosinophilic, clear vacuolated cytoplasm interspersed with focal areas of amyloid deposition. Tumor cells were immunopositive for AE1/AE3, CK14, CK19, β-catenin, CD138, and p63. Key words:Calcifying epithelial odontogenic tumor, clear cell, histopathology, immunohistochemistry.