A retrospective study of 30 basal cell adenomas of the salivary gland in a Brazilian population and literature review.

PURPOSE: The present study aimed to provide the clinicopathological data of Brazilian patients with basal cell adenoma (BCA). METHODS: Records of BCA cases were retrospectively gathered from the Brazilian National Cancer Institute database between 1996 and 2006. All cases were histopathologically reviewed, and the clinicopathological data were collected from the patients' medical files. In addition, an English literature review about this tumor is also presented. RESULTS: Of 1127 salivary gland tumors identified, 30 were BCAs (2.7%). Women were more affected than men (70.0% vs. 30.0%), and the majority (60.0%) were elderly (> 65 years old). The parotid gland was the most frequent location affected (93.3%), followed by the upper lip (3.3%) and submandibular gland (3.3%). Fine-needle aspiration was the main procedure applied to establish a preoperative diagnosis of tumor; however, the results were not always consistent. Histopathologically, the trabecular pattern was the most common type seen (50.0%) among our BCA samples. Most patients underwent superficial or partial parotidectomy. Frey's syndrome was reported only in one case during the follow-up. No recurrence was noted in the present series. The literature review revealed a total of 213 reported cases of BCA in the period investigated. CONCLUSIONS: This is the first case series of BCA reported in Brazil. As occurred in other previously reported series, the clinicopathological data of BCAs are similar and confirm that this type of tumor is rare, develops predominantly in the parotid gland, frequently affects older women, has an indolent behavior, and the affected patients have an excellent prognosis.

Adenoma de células basales parotídeo: reporte de un caso, manejo terapéutico y revisión de la literatura / Basal cell adehoma of the parotid gland: report of a case, therapeutic management and review of the literature

El adenoma de células basales de las glándulas salivares es un tipo deadenoma de aparición infrecuente. La localización más habitual es la superficie de la glándula parótida. Suele debutar clínicamente como una masa fi rme y desplazable de crecimiento lento, asintomática, que puede distinguirse a la palpación en el examen clínico. Afecta más a las mujeres, entre 35 y 80 años. Histológicamente: se observan cordonesy trabéculas de células epiteliales delimitadas por células basaloides y formaciones microquísticas, sin componente mixocondroide del tumormixto, como el presente caso. Se puede dividir en cuatro subtipos atendiendoa su morfología: sólido, tubular, trabecular y membranoso. El tratamiento preferido es la escisión quirúrgica conservadora que incluyeun reborde o margen de tejido normal no afectado. Describimos un caso clínico de adenoma de células basales de la glándula parótida; el hallazgo de esta patología en particular, es muy rara y poco documentada, además realizamos una revisión de la literatura y discutimos el manejo terapéutico y conservador de esta rara enfermedad.

Basal cell adenoma of the salivary glands is a rarely seen type of adenoma.Its most frequent location is the surface of the parotid gland. Itusually appears as a fi rm, mobile, slow-growing asymptomatic mass,which can be detected by palpation during clinical examination. Itis more prevalent in women between the age of 35 and 80 years.Histologically, cords and trabeculae of epithelial cells bounded bybasaloid cells and microcystic formations are visible, without themyxochondroid component of mixed tumors, as in the present case.The basal cell adenoma can be divided into four subtypes based onmorphology: solid, tubular, trabecular and membranous. The treatmentof choice is conservative surgical excision that includes a rimor margin of normal uninvolved tissue. We describe a clinical case ofbasal cell adenoma of the parotid gland, a particular disease that isvery rarely found and seldom documented. We also perform a reviewof the literature and discuss the conservative therapeutic managementof this unusual disease.

Comparison of the blood and lymphatic microvessel density of pleomorphic adenoma and Basal cell adenoma.

BACKGROUND: Pleomorphic adenoma (PA) is the most common tumor of the salivary gland, while basal cell adenoma (BCA) is an uncommon neoplasm. Blood and lymphatic vessels are crucial for tumor metabolism. The aim of this study was to compare the blood and lymphatic vascular density and vascular and endothelial growth factor (VEGF) expression in PA and BCA tumors. In addition, cell proliferation was evaluated in these tumors. METHODS: Blood and lymphatic vessel content, VEGF expression, and cell proliferation were analyzed in 30 cases of PA and 13 cases of BCA by immu-nohistochemistry using antibodies for CD34, CD105, D2-40, VEGF, and Mcm-2. RESULTS: Regarding CD34 and CD105 expression, PA demonstrated a high vascularity and a low number of positive vessels, respectively. D2-40-positive lymphatic vessels were mainly located in the tumor capsules, with small intratumoral lymphatic vessels observed occasionally. VEGF expression revealed a remarkably heterogeneous immunoreactivity, alternating from weak or negative to positive or intense. BCA presented significantly higher CD34, CD34, CD105, D2-40, and VEGF expression compared to PA. No significant difference was found in cell proliferation between the tumors. CONCLUSION: Although PA and BCA are considered part of the same spectrum of differentiation, this study showed that the blood and lymphatic vascularization of these tumors is different.

Tubular variant of basal cell adenoma shares immunophenotypical features with normal intercalated ducts and is closely related to intercalated duct lesions of salivary gland.

AIMS: The morphological criteria for identification of intercalated duct lesions (IDLs) of salivary glands have been defined recently. It has been hypothesised that IDL could be a precursor of basal cell adenoma (BCA). BCAs show a variety of histological patterns, and the tubular variant is the one that presents the strongest resemblance with IDLs. The aim of this study was to analyse the morphological and immunohistochemical profiles of IDLs and BCAs classified into tubular and non-tubular subtypes, to determine whether or not IDL and tubular BCA represent distinct entities. METHODS AND RESULTS: Eight IDLs, nine tubular BCAs and 19 non-tubular BCAs were studied. All tubular BCAs contained IDL-like areas, which represented 20-70% of the tumour. In non-tubular BCA, IDL-like areas were occasional and small (<5%). One patient presented IDLs, tubular BCAs and IDL/tubular BCA combined lesions. Luminal ductal cells of IDLs and tubular BCAs exhibited positivity for CK7, lysozyme, S100 and DOG1. In the non-tubular BCA group, few luminal cells exhibited such an immunoprofile; they were mainly CK14-positive. Basal/myoepithelial cells of IDLs, tubular BCAs and non-tubular BCAs were positive for CK14, calponin, α-SMA and p63; they were more numerous in BCA lesions. CONCLUSIONS: IDL, tubular BCA and non-tubular BCA form a continuum of lesions in which IDLs are related closely to tubular BCA. In both, the immunoprofile of luminal and myoepithelial cells recapitulates the normal intercalated duct. The difference between the adenoma-like subset of IDLs and tubular BCA rests mainly on the larger numbers of myoepithelial cells in the latter. Our findings indicate that at least some BCAs can arise via IDLs.

Pleomorphic adenoma versus basal cell adenoma: an immunohistochemical analysis with B-catenin / Adenoma pleomorfo versus adenoma de células basais: Análise imunohistoquímica com B-catenina

Objective: The objective of this study was to investigate the distribution of β-catenin in pleomorphic adenomas and the basal cell adenomas to clarify its possible role in the etiopathogenesis of these two lesions. Material and Methods: The expression of β catenin (BD Transduction Laboratories) was analyzed by immunohistochemistry in formalinfixed, paraffin-embedded specimens by the avidinbiotin- peroxidase complex method in 10 pleomorphic adenomas and 2 basal cell adenomas. The specimens were analyzed taking into account intensity, distribution and association with myoepithelial cells. Results: The results showed that all cases of pleomorphic adenomas exhibited membranous and cytoplasmic immunostaining and the 2 cases of basal cell adenomas displayed nuclear staining. Higher β-catenin index rates were seen mainly in ductal structures of pleomorphic adenomas and in the nuclei of myoepithelial stromal and myoepithelial cells of solid clusters in basal cell adenomas. Conclusion: In conclusion, this immunohistochemical study may suggests the different degree of differentiation of the myoepithelial cells in these two tumors

Objetivos: O objetivo deste estudo foi investigar a distribuição da β-catenina em adenomas pleomorfos e os adenomas de células basais para esclarecer o seu possível papel na etiopatogenia dessas duas lesões. Material e Métodos: A expressão de β-catenina (BD-Transdução Laboratories) foi analisada por imunohistoquímica em espécimes parafinados fixados em formalina pelo método avidina-biotinaperoxidase em 10 adenomas pleomórficos e 2 adenomas de células basais. Os espécimes foram analisados levando-se em conta a intensidade, quantidade de células marcadas e distribuição em estruturas morfológicas. Resultados: Os resultados mostraram que todos os casos de adenomas pleomorfos exibiram imuno marcação membranosa e citoplasmática e os 2 casos de adenomas de células basais exibiram coloração nuclear. Marcação mais intensa de β-catenina foi vista principalmente em estruturas ductais de adenomas pleomorfos e nos núcleos de células mioepiteliais de estruturas tubulares e trabeculares em adenomas de células basais. Conclusão: Concluindo, este estudo imunohistoquímico sugere distintos graus de diferenciação das células mioepiteliais em cada um destes dois tumores

Basal cell adenoma of the upper lip from minor salivary gland origin.

Basal cell adenoma is an uncommon benign salivary gland neoplasm, presenting isomorphic basaloid cells with a prominent basal cell layer. Taking into account that basal cell adenomas represent 1% of all salivary gland tumors, being the majority of cases in the parotid glands, the goal of this paper is to report a case of basal cell adenoma of the upper lip arising from minor salivary gland.