Fine-needle sampling of salivary gland lesions. VII. Cytology and histology correlation of five cases of epithelial-myoepithelial carcinoma

A cytohistologic correlation of mucoepidermoid carcinoma: emphasizing the rare oncocytic variant

It is well-known that the morphological variability of mucoepidermoid carcinoma (MEC) of the salivary glands may lead to interpretative difficulties on fine-needle aspiration (FNA) diagnosis. In this study we identify morphologic features that may be useful in the FNA diagnosis of MEC. The cohort included 23 cases of MEC; cytology and histology slides were reviewed and assessed for % cystic component, extracellular mucin, mucous and intermediate cells, oncocytes, cells with foamy/clear cytoplasm, keratinized cells and lymphocytes. On FNA 12/23 (52%) cases were diagnosed as consistent with or suggestive of MEC; 6/23 (26%) as salivary gland neoplasm and 5/23 (22%) as no tumor seen. The cystic component was ≥50% in 18/23 (78%) and <50% in 5 cases. The features prevalent in FNA and histology were: mucous cells (96% and 91%), extracellular mucin (91% both), intermediate cells (100 and 83%), lymphocytes (96 and 78%) and cells with foamy/clear cytoplasm (74% both). Oncocytes were seen in 43 and 22% and keratinized cells in 48 and 13% cases. Cases with oncocytes and lymphocytes were interpreted as favor Warthin's tumor on FNA. Presence of mucous cells, cells with foamy/clear cytoplasm, intermediate cells and lymphocytes in a mucinous background are diagnostic indicators of MEC; presence of oncocytes should not refrain from diagnosing MEC in FNA specimens.

Epithelial-myoepithelial carcinoma: a review of the clinicopathologic spectrum and immunophenotypic characteristics in 61 tumors of the salivary glands and upper aerodigestive tract

To further define the clinicopathologic spectrum of epithelial-myoepithelial carcinoma (EMCa), we report the gross, histologic, and immunophenotypic characteristics of 61 tumors seen within a 30-year-period. The mean age at presentation was 60.9 years, with a female predominance (1.5:1). The most common sites were parotid (62.1%), sinonasal mucoserous glands (10.3%), palate (8.6%), and submandibular (8.6%). Most EMCas showed a characteristic nodular/multinodular growth pattern and classic biphasic tubular histology. However, new morphologies in EMCa such as ancient change (8.2%), "Verocay"-like change (3.3%), and sebaceous differentiation (13.1%) were noted. Specific histologic variants were dedifferentiated EMCa (3.3%), oncocytic EMCa (8.2%), EMCa ex pleomorphic adenoma (1.6%), double-clear EMCa (3.3%), and EMCa with myoepithelial anaplasia (3.3%). All cytokeratin cocktails selectively highlighted the epithelial component well. Of the myoepithelial markers, p63, smooth muscle actin and vimentin performed best. Bcl-2 and c-kit were frequently positive (66.7% and 69.2%, respectively). p53 was highly expressed only in 1 dedifferentiated EMCa. The recurrence rate was 36.3% (median disease-free survival 11.34 y), but death was rare with 5-year and 10-year disease-specific survivals of 93.5% and 81.8%, respectively. The most important univariate predictors of recurrence were margin status (log rank P=0.006), angiolymphatic invasion (P=0.002), tumor necrosis (P=0.004), and myoepithelial anaplasia (P=0.038). Thus, EMCa is generally a low-grade tumor with a broader morphologic spectrum than previously thought, with several key features predictive of recurrence. Immunohistochemistry can aid diagnosis by highlighting the biphasic nature of the tumor.

p63 expression of clear myoepithelial cells in epithelial-myoepithelial carcinoma of the salivary gland

BACKGROUND

The typical form of epithelial-myoepithelial carcinoma (EMC) is a double-layered ductal structure, but occasionally EMC presents as a predominant solid growth of clear myoepithelial cells. In the current study, the authors analyzed the distribution and visual patterns of p63-positive clear myoepithelial cells in EMC.

METHODS

Six cases of EMC were evaluated with Papanicolaou staining and with p63 and alpha-smooth muscle actin (SMA) immunostaining. Furthermore, the expressions of p63 and SMA were compared.

RESULTS

The cytologic features of EMC were classified into two types-biphasic and clear cell-dominant type. The biphasic type showed myoepithelial cells with moderate or scant cytoplasm or naked nuclei, overlapping a cohesive cluster of ductal cells. This biphasic type was similar to that in fibroadenoma of the breast. The clear cell-dominant type consisted of myoepithelial cells with a large amount of fragile pale cytoplasm or naked nuclei. In this type, there were many clusters of myoepithelial cells without ductal cells. Nuclear immunoreactivity to p63 was expressed clearly in both biphasic and clear cell-dominant types. Cytoplasm immunoreactivity to SMA was expressed in many myoepithelial cells in the clear cell-dominant type, but only in myoepithelial cells with moderate cytoplasm in the biphasic type.

CONCLUSIONS

Clear myoepithelial cells in EMC were distributed in various patterns. The authors concluded that p63 is an especially useful marker of myoepithelial cells with naked nuclei in EMC.

Papillary thyroid carcinoma with an adenoid cystic pattern: Report of a case with fine-needle aspiration cytology and immunocytochemistry

Although fine-needle aspiration (FNA) cytologic features of conventional papillary thyroid carcinoma (PTC) and some of its variants have been documented in the literature, PTC with an adenoid cystic pattern has not so far been described. A 35-year-old woman presented with solitary cold nodule in the right lobe of thyroid. FNA smears from the nodule showed features of PTC such as papilliform clusters, monolayered sheets, psammoma bodies, increased frequency of nuclear grooves, and intranuclear cytoplasmic inclusions. In addition, there were areas of follicular formation and light-pink to deep-purple hyaline globules with a laminated appearance and surrounded by neoplastic cells, reminiscent of adenoid cystic carcinoma. These globules were present in 53% of the follicles. Immunocytochemical staining for thyroglobulin yielded positive cytoplasmic reaction in the neoplastic cells. Histopathology of the thyroidectomy specimen confirmed the cytodiagnosis of PTC. The hyaline globules were present focally and were light pink to deep purple with a laminated appearance resembling psamomma bodies. The colloid and follicular cells were positive for thyroglobulin but the hyaline globules were negative. Von Kossa staining for calcium revealed positive reaction in the psamomma bodies and some of the hyaline globules, indicating that the globules may be the beginning of psammoma bodies. Thus, FNA cytology was useful in diagnosing an unusual variant of PTC.

Fine-needle aspiration cytological findings in five cases of epithelial-myoepithelial carcinoma of salivary glands

The cytologic features of five cases of epithelial-myoepithelial carcinoma arising in major salivary glands (four parotid and one submandibular gland) are presented. All cases were initially diagnosed as low-grade malignancies. The smears were generally cellular, with no specific architectural pattern. Single cells and naked nuclei were prominent in all cases. A biphasic epithelial (small-cell) and myoepithelial (large/clear-cell) pattern was identified readily in two cases and with difficulty in one case. The biphasic pattern may be subtle or absent since the clear cells have a fragile cytoplasm and often appear as naked nuclei. The differential diagnosis includes adenoid cystic carcinoma, polymorphous low-grade adenocarcinoma, and cellular pleomorphic adenoma.

Peripheral primitive neuroectodermal tumor of the parotid gland region: report of a case with fine-needle aspiration findings

A case of peripheral primitive neuroectodermal tumor of the parotid gland region in a 38-yr-old woman is reported. She had a 1-yr history of a large, firm, and slightly tender left parotid-region mass. CT scan showed an invasive tumor involving the parotid gland, mandible, infratemporal fossa, and parapharyngeal space. Fine-needle aspiration cytology of the mass showed a highly cellular, poorly cohesive smear pattern exhibiting small cuboidal cells, with fibrillary cytoplasm forming occasional rosette-like structures. Numerous intact single cells with fragile cytoplasm, finely granular chromatin, and inconspicuous nucleoli were present together with free-lying nuclei in the background. Histologic, immunohistochemical, and ultrastructural findings confirmed the diagnosis. Diagn. Cytopathol. 2000;22:161-166. Published 2000 Wiley-Liss, Inc.

Fine-needle sampling findings in 26 carcinoma ex pleomorphic adenomas: diagnostic pitfalls and clinical considerations

Preoperative fine-needle samplings (FNS) of 26 histologically proven carcinoma ex pleomorphic adenomas (24 primary tumors and 2 local recurrences in 24 patients) were retrospectively reviewed in order to evaluate their cytologic characteristics. Histologically, 17 were high-grade and 9 were low-grade carcinomas; 10 carcinomas were intratumoral (in situ), and 16 were infiltrative. A cytologic diagnosis of malignancy was established in 13 (50%) cases, 2 (7.7%) were suspicious, and 11 (42.3%) were negative for malignancy (10 pleomorphic adenomas, 1 inflammation). The majority (76.5%) of high-grade carcinomas were correctly diagnosed by FNS, regardless of invasiveness. Paradoxically, most (77.8%) negative results were encountered in low-grade carcinomas. Accurate diagnosis of malignancy on FNS is achieved in high-grade tumors and low sensitivity may cause interpretative difficulties in low-grade tumors. Diagn. Cytopathol. 1999; 21:163-166.