Fine needle aspiration cytology in a case of pleomorphic adenoma of the parotid gland

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  The smears from the FNA of the parotid contained abundant cells.
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  Small groups of epitelial cells and abundant myxoid stroma.
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  Stromal cells with oval or elongated nuclei embedded in abundant fibrillar intercelular substance.
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  Aspirate showing a large cohesive sheet of small epithelial cells surrounded by stromal
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  Some area contain mainly isolated cells, which have a distinct oval or poligonal cytoplams oval round or slightly oval nuclei.
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  A dense epithelial cellular mass composed of tightly packed small cuboidal cells.
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  Mixoid stromal tissue contain darker groups of ductal cells. The stroma is intensely staining which has no recognizable cells.
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  Some cells shows characteristic plasmacytoid-appearing cells with eccentrically placed nuclei dense cytoplasm and distinct cytoplasmic borders.
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  Epithelial cells of monotonous size with round or slightly oval nuclei containing evenly distributed finely granular chromatin and single tiny nucleoli.
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  Mixture of epithelial and myxomatous elements.
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  Epithelial cell predominance the degree of nuclear pleomorphism here non suggested malignancy.
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  Some small epithelial cells and fragment of myxoid stroma.
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  The fibrillar myxoid stroma is easyly identified en MGG method.

The incidence of neoplastic disease in the salivary glands is only 2 per 100.000 of the population, yet since the first introduction of fine needle aspiration biopsy (FNAB) these organs have provided an intriguing target.
FNAB is now a well established technique in the management of salivary gland disease but it also one of the most problematical tasks faced by cytopathologists.
Pleomorphic adenoma, is by far the most common of all salivary gland neoplasm constitute about 75% of major and minor salivary gland tumors. The great majority (78%) of pleomorphic adenomas are found in the superficial portion of the parotid glands, most of the tumors arise in the superficial portion of the parotid gland. The tumors occur most commonly in patients aged 30-50 years and are slightly more common in females.
The tumors are composed of epithelial and mioepithelial elements and a sparse to abundant stroma. The variability in histologic pattern is typically reflected in FNAB.
Pleomorphic adenoma is the lesion most likely to be encountered in FNAB practice. Aspirates contain plentiful epithelial cells which are closely intermingled with loose dusters of mesenchymal cells and fibrillary mucomyxomatous background substance. The cytologic features of pleomorphic adenoma are usually quite characteristic and the correct cytologic diagnosis can almost be established. The cytological diagnosis of the great majority of pleomorphic adenomas is quite straightforward.
The images correspond to the FNAB of a woman aged 39 years with a palpable left parotid nodular elevation. In this case the presence of characteristic cytological pattern should allow the diagnostic of pleomorphic adenoma. The distinction of pleomorphic adenoma from well differentiated adenoid cystic carcinoma is not always easy.