Román Carlos

Syphilis: The Renaissance of an Old Disease with Oral Implications

Syphilis is caused by Treponema pallidum an anaerobic filamentous spirochete. In recent years, striking outbreaks have occurred in USA, Canada, Russia, China and some areas of Central and Eastern Europe. Main epidemiology changes reflect sex industry, sexual promiscuity, decreasing use of barrier protection (i.e. condoms) due to false sense of security that nowadays sexually transmitted diseases are curable and lack of pertinent knowledge. Considering that the initial presentation of syphilis may be the oral cavity, it is of great relevance to include this disease in the differential diagnosis of unusual oral ulcerations and white patches. Primary syphilis is a highly infectious disease in which inappropriate treatment may be apparently curative while the patient remains highly infectious. It is then of pivotal importance that clinicians maintain a high clinical index of suspicion. At the present time, clinical-pathologic correlation together with serologic studies remain essential in establishing the diagnosis of syphilis.

Bilateral central ossifying fibroma affecting the mandible: report of an uncommon case and critical review of the literature

Ossifying fibroma (OF) is a well demarcated benign neoplasm primarily found in the jaw and composed of fibrocellular tissue and mineralized material. Occurrence of multiple OFs (synchronous) is rare in the jaws, and only 10 cases have been documented. The aim of this report was to present an additional case of bilateral central OF in the mandible of a patient not affected by the hyperparathyroidism–jaw tumors syndrome (HPTJT), emphasizing the features that distinguish this lesion from HPT-JT and performing a critical review of the current literature and concepts. Benign fibro-osseous lesions (FOLs) are a poorly defined and to some extent controversial group of lesions affecting the jaws and craniofacial bones. FOL refers to a group of pathologic processes in which normal bone is replaced by fibroblasts and collagen fibers containing variable amounts of mineralized material. This group encompasses fibrous dysplasia, benign fibro-osseous neoplasms (central ossifying fibroma), and a heterogeneous group of reactive lesions (osseous dysplasias). Because of the histopathologic similarities among these lesions, the definitive diagnosis requires a precise correlation of the clinical, histopathologic, and imaging findings.

Immunohistochemical expression of p16, p21, p27 and cyclin D1 in oral nevi and melanoma.

The acquisition of abnormalities at G1/S is considered a crucial step in the genesis and progression of melanoma. The expression of cell cycle regulators has also been used in various neoplasms as an adjunct to diagnosis. The aim of this study was to compare the expression of p16, p21, p27 and cyclin D1 in oral nevi and melanomas. Expression of these cell cycle regulatory proteins was evaluated by immunohistochemistry in 51 oral melanocytic lesions, including 38 intramucosal nevi and 13 primary oral melanomas. p16 and p27 were highly expressed in intramucosal nevi, whereas p21 and cyclin D1 expression was higher in oral melanomas. The results indicate that p21 and cyclin D1 may be involved in the development of oral melanomas, and eventually they may be useful in the differential diagnoses of oral benign and malignant melanocytic lesions.

Primary oral melanoma: a histopathological and immunohistochemical study of 22 cases of Latin America.

Objective: The aim of this study was to analyze the histopathological and immunohistochemical characteristics of 22 cases of primary oral melanomas (OM). Study Design: Twenty two cases of primary oral melanoma were analyzed by description of their histopathological features and immunohistochemical study using the antibodies S-100, HMB-45, Melan-A and Ki-67. Results: The mean age was 58 years and 14 cases were female. The main affected sites were the hard palate, followed by the upper gingiva. Microscopically, 15 cases presented level III of invasion, 2 cases were amelanotic and 13 showed a mixed epithelioid and plasmacytoid or spindle cells composition. Some cases showed necrosis, perivascular and perineural invasion. S-100 and HMB-45 were positive in all cases, but 3 cases were negative for Melan-A. The proliferative index with Ki-67 was high, with labeling index ranging from 15.51% to 63% of positive cells. Conclusion: S-100 and HMB-45 are more frequently expressed than Melan-A in primary oral melanomas and these markers are helpful to confirm the diagnosis. Key words:Oral melanoma, histopathology, immunohistochemistry.

Metastatic renal cell carcinoma to the oral cavity and clear cell mucoepidermoid carcinoma: comparative clinicopathologic and immunohistochemical study.

BACKGROUND Metastatic clear cell renal cell carcinoma (CCRCC) should be considered in differential diagnosis of intraoral clear cell tumors, including mucoepidermoid carcinoma (MEC). OBJECTIVE AND STUDY DESIGN We compared the clinical, histologic, histochemical, and immunohistochemical characteristics of 9 oral metastatic CCRCCs and 8 intraoral clear cell MECs. RESULTS Oral metastatic CCRCC affected salivary-gland containing tissues in 7 cases (78%). Microscopically, oral metastasis revealed a proliferation of neoplastic clear cells arranged in an alveolar pattern with central blood vessels, features that were not seen in any intraoral clear cell MEC. Mucicarmine staining was positive only in clear cell MEC. Immunohistochemistry showed similarities in cytokeratin expression; vimentin and CD10 were expressed in all oral metastatic CCRCCs but in only 1 clear cell MEC each. CONCLUSIONS Besides clinical history, the alveolar pattern, vessel distribution, absence of mucicarmine staining, and vimentin and CD10 immunoexpression are useful in histologic differential diagnosis of CCRCC and clear cell MEC.

Head and neck amyloidosis: clinicopathological features and immunohistochemical analysis of 14 cases

BACKGROUND Amyloidosis is associated with or caused by amyloid deposition. These fibrillar proteins may be deposited extracellularly causing tissue damage or impairment. OBJECTIVES The aim of the study was to retrospectively review pathology archives in two oral diagnostic centers for cases fulfilling criteria of amyloidosis and to differentiate AA and AL types of amyloidosis. METHODS The clinicopathological features, alkaline Congo red staining, with and without pretreatment with potassium permanganate, and immunohistochemical (IHC) staining with anti-AA, anti-kappa (κ), and anti-lambda (λ) light chain antibodies were carried out and analyzed. RESULTS The search identified 14 cases. Ten patients were women and four were men, with a mean age of 58 years. Eleven patients had systemic involvement by amyloidosis (associated either with multiple myeloma or plasma cell dyscrasia/monoclonal gammopathies), while three presented the localized type, one of them associated with plasmacytoma. All cases showed positivity for κ or λ light chains (AL-amyloid) and presented resistance to the potassium permanganate pretreatment. CONCLUSIONS Our results show that the head and neck region is preferentially affected by systemic AL-amyloidosis, usually associated with plasma cell dyscrasia. Interestingly, two cases affected by inflammatory rheumatic diseases presented AL-amyloid deposition. Moreover, even after pretreatment with potassium permanganate, which was helpful in highlighting the presence of AL-amyloid, in agreement with the IHC findings, clinical classifications should be carefully made in systemic amyloidosis.

Expression of minichromosome maintenance 2, Ki-67, and geminin in oral nevi and melanoma.

Evaluation of cell cycle using antibodies against nuclear proteins involved in regulating DNA replication has gained special interest in the effort to predict biologic behavior of benign and malignant tumors. The aim of this study was to analyze the expression of minichromosome maintenance 2, Ki-67, and geminin in oral nevi and melanomas. Expression of these cell proliferation markers was evaluated by immunohistochemistry in 49 oral melanocytic lesions, including 38 intramucosal nevi and 11 primary oral melanomas. The labeling index of each proliferation marker was assessed considering the percentage of cells expressing nuclear positivity out of the total number of cells, counting 1000 cells per slide. Minichromosome maintenance 2, Ki-67, and geminin were rarely expressed in intramucosal nevi, in contrast to oral melanomas, which showed high levels of these cell proliferation markers, particularly minichromosome maintenance 2, indicating it is a more sensitive marker in primary oral melanomas than Ki-67 and geminin. These results indicate that these markers may be involved in the pathogenesis of oral melanomas and could be eventually useful as an additional diagnostic tool for differential diagnosis of oral benign and malignant melanocytic lesions.

Calcifying epithelial odontogenic tumor (CEOT): a clinicopathologic and immunohistochemical study and comparison with dental follicles containing CEOT-like areas

OBJECTIVE To describe the clinicopathologic, immunohistochemical, and scanning electron microscopic features of 19 cases of calcifying epithelial odontogenic tumor (CEOT) in comparison to 4 cases of dental follicles containing CEOT-like areas (DF-CEOT). STUDY DESIGN A collaborative Latin American retrospective study. RESULTS CEOT and DF-CEOT showed a slight predilection for females, mostly affecting the posterior mandible. CEOTs were classified as epithelium-rich (8 cases), amyloid-rich (4), and calcification-rich (3), and 4 cases showed similar proportion of the 3 components. DF-CEOTs contained odontogenic epithelium, amyloid, calcification, and clear cells. Epithelial cells were positive for cytokeratins CK5 and CK19, E-cadherin, and syndecan 1 (CD138), and focally for amyloid A. In CEOT, amyloid was positive for CD138 and amyloid A, and calcification for CK5, CD138, and amyloid A. In DF-CEOT, calcification was positive for amyloid A. CEOT showed higher Ki-67 protein and minichromosome maintenance complex component 2 (MCM-2) labeling indices than did DF-CEOT. In scanning electron microscopy, CEOT calcified material resembled bone in the 3 cases classified as calcification-rich. CONCLUSIONS CEOT and DF-CEOT showed histomorphologic and immunohistochemical similarities, and the histogenetic significance of these features should be further studied.

Ghost cells in pilomatrixoma, craniopharyngioma, and calcifying cystic odontogenic tumor: histological, immunohistochemical, and ultrastructural study.

BACKGROUND Pilomatrixoma, craniopharyngioma, and calcifying cystic odontogenic tumor are the main entities presenting ghost cells as an important histological feature, in spite their quite different clinical presentation; it seems that they share a common pathway in the formation of these cells. The aim of this study is to examine and compare the characteristics of ghost and other cells that form these lesions. METHODS Forty-three cases including 21 pilomatrixomas, 14 craniopharyngiomas, and eight calcifying cystic odontogenic tumors were evaluated by immunohistochemistry for cytokeratins, CD138, β-catenin, D2-40, Glut-1, FAS, CD10 and also by scanning electron microscopy. RESULTS The CKs, CD138, β-catenin, Glut-1, FAS, and CD10 were more often expressed by transitional cells of craniopharyngioma and calcifying cystic odontogenic tumor, compared with pilomatrixoma. Basaloid cells of pilomatrixoma showed strong positivity for CD138 and CD10. Differences on expression pattern were identified in transitional and basal cells, as ghost cells were negative for most antibodies used, except by low expression for cytokeratins. By scanning electron microscopy, the morphology of ghost cells were similar in their fibrillar cytoplasm, but their pattern varied from sheets in pilomatrixoma to small clusters in craniopharyngioma and calcifying cystic odontogenic tumor. CONCLUSIONS Mechanisms involved in formation of ghost cells are unknown, but probably they follow different pathways as protein expression in the basal/transitional cells was not uniform in the three tumors studied.

Giant cell lesions in noonan syndrome: case report and review of the literature.

Noonan-like/multiple giant cell lesion syndrome (NS/MGCLS) is a rare condition with phenotypic overlap with Noonan syndrome (NS). Once thought to be a specific and separate entity, it is now suggested to be a variant of the NS spectrum. We report a patient with classical cardinal features of NS, including short stature, mild ptosis, hypertelorism, down-slating palpebral fissures, low-set and posteriorly angulated ears, short neck, pectus excavatum, widely spaced nipples and cryptochidism, which were associated with bilateral central giant cell lesions in the mandible and germ-line mutation (C218T, Thr73Ile) in the exon 3 of the PTPN11 gene. The similar clinical and genetic aspects support the observation that NS/MGCLS is a variant of NS and giant cell lesions are an integrant part of this disorder.