Pablo Agustin Vargas

Salivary gland tumors in a Brazilian population: a retrospective study of 124 cases

UNLABELLED Salivary gland tumors constitute a highly heterogeneous histopathologic group. There are few epidemiological studies of large series of benign and malignant salivary gland tumors in Brazil. MATERIAL AND METHODS Hospital records of 124 patients with salivary gland tumors diagnosed from January 1993 to December 1999 were reviewed. The patients were analyzed according to gender, age, size, location, and histopathology of the tumor. RESULTS AND CONCLUSIONS Patients with benign and malignant tumors presented with a mean age of 47.7 and 48.8 years, respectively. The frequency of benign tumors was 80% (n = 99) and malignant tumors 20% (n = 25). Tumors were localized in the parotid gland 71% (n = 88), in the submandibular gland 24% (n = 30), and in the minor salivary glands 5% (n = 6). The most common benign tumors were pleomorphic adenoma in 84% (n = 84) and Warthins tumor in 13% (n = 13). Among malignant tumors, mucoepidermoid carcinoma was the most common in 52% (n = 13), adenoid cystic carcinoma occurred in 20% (n = 5), and carcinoma ex pleomorphic adenoma was detected in 12% (n = 3).

Basaloid squamous carcinoma of oral cavity: a histologic and immunohistochemical study

Basaloid squamous carcinoma (BSC) is an aggressive variant of squamous cell carcinoma (SCC) with a predilection for the upper aerodigestive tract. In the English literature, approximately 40 cases of BSC have been described in the oral cavity. BSC has frequently been confused with adenoid cystic carcinoma (ACC), basal cell adenocarcinoma, and undifferentiated SCC. The purpose of the investigation was to examine the histological features and immunohistochemical expression of differentiation-related substances, including cytokeratin (CK) subtypes, vimentin, S-100, chromogranin, laminin, and type IV collagen, for the characterization of biological features of these tumours. We studied three cases of BSC of the oral cavity, three cases of ACC, and one case of basal cell adenocarcinoma. Well-differentiated and undifferentiated SCCs were also studied for comparison. The BSCs showed many histopathologic similarities to cases previously reported. Among the CK subtypes analyzed, CK14 was the only subtype expressed by all basaloid cells of BSC. Potentially useful for the differential diagnosis was the finding of CKs 7 and 19 expression in the basaloid cells of ACC, and CKs 7 and 8 in basal cell adenocarcinoma. In BSCs, laminin and type IV collagen were found in the microcystic spaces between basaloid cells, but neither ACCs nor basal cell adenocarcinoma showed this feature. These data suggest that immunohistochemical findings are helpful in distinguishing BSC of the oral cavity from other histopathologically similar tumours.

Dental Alterations Associated with X-Linked Hypophosphatemic Rickets

The X-linked hypophosphatemic rickets is a rare metabolic disorder characterized by low serum phosphate levels caused by a decreased renal tubular reabsorption of inorganic phosphates. The initial complaints are a delay in the development of walking caused by deformity of the legs. Oral findings include poorly mineralized dentin, enlarged pulp chambers and root canals, and periradicular abscesses in caries-free teeth. We present three patients from the same family with X-linked hypophosphatemic rickets showing bone and dental alterations.

Clinicopathologic analysis of 493 cases of salivary gland tumors in a Southern Brazilian population

OBJECTIVE The aim of this study was to determine the distribution and demographic features of salivary gland tumors (SGTs) in a large Brazilian population. STUDY DESIGN A total of 493 cases of SGTs diagnosed between 2001 and 2011 from a general pathology laboratory and an oral pathology service were reviewed with respect to their clinicopathologic features. RESULTS A total of 369 tumors were benign and 124 were malignant. The mean age of patients with benign tumors was 46.3 years and that of patients with malignancies was 54.0 years. The parotid gland was the most common location (42.3%). Pleomorphic adenoma (PA) and Warthins tumor were the most common benign neoplasias, whereas mucoepidermoid carcinoma (MEC) and adenocarcinoma, not otherwise specified, were the most frequent malignancies. CONCLUSIONS The present data confirm that PA and MEC are the most common benign and malignant SGTs. However, it is important to consider that differences in tumor types may be influenced by whether a tumor derives from a medical or a dental service.

Oral pigmented lesions: Clinicopathologic features and review of the literature

Diagnosis of pigmented lesions of the oral cavity and perioral tissues is challenging. Even though epidemiology may be of some help in orientating the clinician and even though some lesions may confidently be diagnosed on clinical grounds alone, the definitive diagnosis usually requires histopathologic evaluation. Oral pigmentation can be physiological or pathological, and exogenous or endogenous. Color, location, distribution, and duration as well as drugs use, family history, and change in pattern are important for the differential diagnosis. Dark or black pigmented lesions can be focal, multifocal or diffuse macules, including entities such as racial pigmentation, melanotic macule, melanocytic nevus, blue nevus, smoker’s melanosis, oral melanoacanthoma, pigmentation by foreign bodies or induced by drugs, Peutz-Jeghers syndrome, Addison´s disease and oral melanoma. The aim of this review is to present the main oral black lesions contributing to better approach of the patients. Key words:Pigmentation, melanin, oral, diagnosis, management.

Central odontogenic fibroma: new findings and report of a multicentric collaborative study

OBJECTIVE The aim of this study was to describe the clinicopathologic and immunohistochemical characteristics of 14 cases of central odontogenic fibroma (COF), and the ultrastructural features of 2 of them. STUDY DESIGN Collaborative retrospective study based on the records of 4 oral pathology diagnostic services in Latin America based on the current World Health Organization classification. RESULTS There were 7 male and 7 female patients (mean age 31.8 years). Eight tumors occurred in the maxilla and 6 in the mandible. Thirteen cases were epithelium-rich and 1 epithelium-poor COF. Three were classified as hybrid COF with giant cell lesion. Mean size of the hybrid lesions were larger than pure COF (3.8 vs. 2.4 cm). Odontogenic epithelial islands were immunoreactive for cytokeratin (CK) AE1/AE3, CK5, CK14, CK19, and 34BE12 and negative for CK1 and CK18. Langerhans cells positive for S-100 and CD1a were found within the epithelial islands in 6/6 tested cases. CD68 was expressed in the giant cells of the hybrid lesions and in a few mononuclear cells of 2 cases of COF. Ki-67 index was <1% in all cases. In 6 tumors (42.8%), there were small globular eosinophilic droplets within the epithelial islands, which were positive for collagen type IV, and 9/13 cases (69.2%) were focally positive for smooth muscle actin. In addition to fibroblasts, myofibroblastic differentiation was found in the 2 cases studied ultrastructurally. CONCLUSIONS Immunohistochemistry was useful to confirm the presence of epithelium and to exclude other central fibrous tumors. COF also contains a variable number of mast cells, Langerhans cells, and myofibroblasts, and further studies are needed to better understand the participation of these cells in COF histogenesis.

Clinicopathological features and immunohistochemical expression of p53, Ki-67, Mcm-2 and Mcm-5 in proliferative verrucous leukoplakia.

BACKGROUND Proliferative verrucous leukoplakia (PVL) is a distinct and aggressive type of oral leukoplakia which affects elderly women without risk behavior and presents high rates of malignant transformation. The objective of the present study was to evaluate the clinicopathological characteristics and the distribution of cell proliferation markers, aiming to elucidate the distinct biological behavior of the PVL. METHODS Clinical and microscopical features of 12 patients with PVL were reviewed. Immunohistochemical analysis for p53, Ki-67, Mcm-2 and Mcm-5 were performed and the data were correlated. RESULTS All patients were women, above 50 years of age, 91.7% were non-smoker and 100% were non-habitual drinker. Alveolar ridge (66.6%), tongue (50%) and buccal mucosa (41.6%) were the most affected sites. Four patients developed squamous cell carcinoma (SCC). The immunohistochemical findings showed higher positivity for p53, Ki-67, Mcm-2 and Mcm-5 in SCCs. However, some patients with mild or moderate dysplasia, specially the patients who developed SCC, presented high expression of Mcm-2 and Mcm-5. CONCLUSIONS High immunoexpression of Mcm-2 and Mcm-5 in mild and moderate dysplasia could be helpful to predict the malignant transformation of PVL.

High incidences of DNA ploidy abnormalities in tongue squamous cell carcinoma of young patients: an international collaborative study

Santos‐Silva A R, Ribeiro A C P, Soubhia A M P, Miyahara G I, Carlos R, Speight P M, Hunter K D, Torres‐Rendon A, Vargas P A & Lopes M A (2011) Histopathology 58, 1127–1135
High incidences of DNA ploidy abnormalities in tongue squamous cell carcinoma of young patients: an international collaborative study

Cleidocranial dysplasia: oral features and genetic analysis of 11 patients

BACKGROUND Cleidocranial dysplasia (CCD) is a dominantly inherited autosomal disease characterized by typical bone defects including short stature, persistently open or delayed closure of the cranial sutures, and hypoplastic or aplastic clavicles. Oral features are frequent and include supernumerary teeth, delayed eruption or impaction of the permanent teeth, and malocclusion. Heterozygous mutations in RUNX2 gene, which encodes a transcription factor essential for osteoblast differentiation, were identified as the etiological cause of CCD. OBJECTIVE AND METHODS Herein, we performed physical and radiographic examination and screening for RUNX2 mutations in 11 patients from five families with CCD. RESULTS All patients demonstrated the classical phenotypes related to CCD. Families whose affected members had several dental alterations such as multiple impacted and supernumerary teeth demonstrated heterozygous missense mutations (R190Q and R225Q) that impair the runt domain of RUNX2. On the other hand, CCD patients from families with low frequency of dental abnormalities showed no mutation in RUNX2 or mutation outside of the runt domain (Q292fs→X299). CONCLUSION The current findings suggest a correlation between dental alterations and mutations in the runt domain of RUNX2 in CCD patients. Further clinical and genetic studies are needed to clarify the relationship between phenotypes and genotypes in CCD and to identify other factors that might influence the clinical features of this uncommon disease.

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.