Langerhans cell histiocytosis of the thyroid diagnosed by fine needle aspiration cytology. A case report

BACKGROUND: Langerhans cell histiocytosis rarely involves the thyroid gland even in patients with multifocal disease. Unifocal disease apparently confined to the thyroid is even more rare. CASE: A 30-year-old woman presented with a 6-cm mass in the right and a 3-cm mass in the left lobe of the thyroid. Fine needle aspiration cytology showed isolated, loose aggregates and histiocytelike cells with grooved or contorted nuclei mixed in varying proportions with many mature eosinophils, scattered and small lymphocytes, multinucleated giant cells and foamy histiocytes. CONCLUSION: The cytologic features of Langerhans cell histiocytosis are characteristic. A fine needle aspiration cytology diagnosis is confirmed by histopathologic studies, imunohistochemical staining and ultrastructural studies.     

Columnar cell variant of papillary thyroid carcinoma. Report of a case with cytologic findings

BACKGROUND: The columnar and tall cell variants of papillary thyroid carcinoma (PTC) are uncommon variants and have generally been regarded as more aggressive forms in comparison to the more common classic papillary and follicular subtypes. Cytologic diagnosis of these rare variants is elusive since the characteristic nuclear features of the usual papillary thyroid carcinoma are very often absent or inconspicuous. We present a case of the columnar cell variant of PTC in a young woman that demonstrates the diagnostic challenge. CASE: A 24-year-old woman presented with a solitary, 3-cm mass in the left aspect of the thyroid. The aspirate consisted of a moderately cellular sampling of sheets, papillary clusters and microfollicles of cells with oval nuclei and uniform, finely granular chromatin. These cells were arranged in a peudostratified manner around well-defined fibrovascular cores. There were no intranuclear inclusions or well-defined nuclear grooves in the cells of the aspirate. There was also absence of colloid despite the presence of well-formed follicles. The resected thyroid revealed a columnar cell variant of PTC. CONCLUSION: The cytologic features of columnar cell-type PTC are at variance with those of classic PTC and are elusive in fine needle aspiration cytology. It is the lack of classic cytologic features of PTC that is distinctly apparent, yet it is the monomorphism of cells in the aspirate, their papillary configuration and their pseudostratification in well-formed fibrovascular cores that are the keys to the diagnosis. Immunohistochemical staining to rule out other thyroid neoplasms can be performed to aid in the diagnosis.     

Atypical follicular cells with equivocal features of papillary thyroid carcinoma is not a low-risk cytologic diagnosis

Objective: To determine whether or not significant differences in the risk of malignancy exist between subgroups of atypical follicular cells in The Bethesda System for Reporting Thyroid Cytology (TBSRTC) in patients who underwent surgical resection. Study Design: Between 2004 and 2009, consecutive thyroid fine-needle aspirates at our institutions with a cytologic diagnosis of 'atypical follicular cells' were retrieved and subclassified using the diagnosis and diagnostic comment as: (1) atypical follicular cells with equivocal features of papillary carcinoma [cannot exclude papillary thyroid carcinoma (PTC)] and (2) atypical follicular cells, other patterns. The risks of malignancy for excised nodules were calculated and comparisons were made between these subgroups. Categorical analysis was performed using a 2-tailed Fisher's exact test, and p < 0.05 was considered statistically significant. Results: A total of 7,072 thyroid fine-needle aspiration cases were retrieved, with 1,542 (21.8%) having a histologic follow-up. There were 222 (3.1%) cases of 'atypical follicular cells', with 127 (57.2%) having a histologic correlation and 33 having confirmed malignancies. Atypical follicular cells, cannot exclude PTC, have a significantly higher risk of malignancy than atypical follicular cells, other patterns (45.8 vs. 13.9%, p < 0.01). Conclusions: Atypical follicular cells with equivocal features of papillary carcinoma is not a low-risk cytologic diagnosis.     

Fine needle aspiration of poorly differentiated oxyphilic (Hürthle cell) thyroid carcinoma: a case report

BACKGROUND: Poorly differentiated oxyphilic (Hürthle cell) carcinomas are a more recently described variant of poorly differentiated thyroid carcinoma and are characterized by a prominent Hürthle cell component in a solid or trabecular arrangement. Clinically, poorly differentiated oxyphilic carcinomas behave more aggressively as compared to classic Hürthle cell carcinomas, which have a predominantly follicular pattern. Although the histology of these rare thyroid tumors has been reported in the literature, the cytologic features on fine needle aspiration biopsy have not been described before. CASE: A 73-year-old man with a long history of radioactive iodine and levothyroxine therapy for multinodular goiter presented with a painful, rapidly expanding, 6-cm, left thyroid mass with aggressive radiologic features. Fine needle aspiration biopsy of the mass yielded extremely cellular smears with a dual population of medium-sized follicular cells and numerous Hürthle cells. Subsequent thyroidectomy confirmed the malignant nature of this Hürthle cell-rich tumor, warranting a diagnosis of poorly differentiated oxyphilic (Hürthle cell) thyroid carcinoma. CONCULSION: Poorly differentiated oxyphilic thyroid carcinoma is an aggressive variant of Hürthle cell carcinomas and must enter the differential diagnosis when fine needle aspiration biopsy of a radiologically aggressive thyroid mass yields extremely hypercellular smears with a prominent Hürthle cell component.     

Application of magnetic-resonance-spectroscopy- based metabolomics to the fine-needle aspiration diagnosis of papillary thyroid carcinoma

Objective: This study explores the potential use of high-resolution magic angle spinning proton magnetic resonance spectroscopy as an ancillary diagnostic technique for papillary thyroid carcinoma in thyroid fine-needle aspiration biopsies. The method has already been shown to be effective in the classification of various other nonthyroid cancers. Study Design: Twenty-six samples (13 paired cytologic and histologic samples) from patients being evaluated for thyroid abnormalities at the Massachusetts General Hospital were spectroscopically analyzed, and included: papillary thyroid carcinomas (n = 4), follicular adenomas (n = 4), and normal thyroid samples (n = 5). Metabolic profiles were statistically generated based on the spectroscopy results, which were then correlated with the final cytologic and histologic diagnoses from the same samples to determine the diagnostic capacity of the profiles. Results: Principal component analysis of the tissue samples revealed statistically significant correlations among principal components and various cytologic and histologic features. Canonical score 1, calculated with principal components in correlation with analyzed pathologies, revealed the ability of the metabolic profile to differentiate all three examined histologic tissue groups (ANOVA, p < 0.0001). Applying coefficients of principal components and canonical scores obtained with tissue samples directly onto spectral results of cytology samples, the calculated canonical score 1 also revealed similar trends among the three fine-needle aspiration biopsy groups. In particular, the papillary thyroid carcinoma group exhibited significant differences from both the adenomatous and normal cytology groups (p < 0.0170). Conclusions: The results indicate the potential of high-resolution magic angle spinning proton magnetic resonance spectroscopy as an ancillary marker for papillary thyroid carcinoma in fine-needle aspiration biopsy specimens.     

Signet-ring follicular adenoma of the thyroid diagnosed by fine needle aspiration. Report of a case with cytologic description

BACKGROUND: Follicular cells of the thyroid may undergo squamous, oncocytic or clear cell metaplastic changes. Of these, the clear cell change with signet-ring formation is the most unusual, and follicular adenoma of the thyroid with signet-ring formation is extremely rare. We describe for the first time the cytologic features of a clear cell adenoma of the thyroid obtained by fine needle aspiration (FNA). CASE: A 48-year-old woman in a euthyroid state presented with a 2-cm, right-sided thyroid nodule. Smears obtained by FNA of the nodule revealed clusters of large signet-ring cells in a bloody background. The signet-ring cells were round to oval, with large cytoplasmic vacuoles and hyperchromatic, eccentric nuclei. Colloid in the background was very scanty. Histologic examination of the right hemithyroidectomy specimen revealed a signet-ring follicular adenoma. CONCLUSION: Lack of familiarity with signet-ring cell adenoma of the thyroid could lead to an erroneous diagnosis of metastatic signet-ring cell carcinoma.     

Renal cell carcinoma metastatic to follicular adenoma of the thyroid gland. A case report

BACKGROUND: Renal cell carcinoma is an unpredictable tumor that can recur many years after the original diagnosis and metastasize to uncommon sites, including the thyroid gland. Differential diagnosis from primary thyroid tumor is often difficult both clinically and pathologically. We report a case of metastatic renal cell carcinoma in follicular adenoma of the thyroid gland. CASE: A 48-year-old woman presented with a 3-cm-diameter, palpable mass in the left lobe of the thyroid gland. The patient's history included removal of a left renal mass, which was conventional renal cell carcinoma. Fine needle aspiration cytology smears contained a few small clusters of polygonal cells with abundant, clear cytoplasm and irregular, hyperchromatic nuclei as well as bland-looking thyroid follicle cells and stromal cells. A papillary or follicular growth pattern was not detected. A cell block made from the aspirated sample was composed mainly of clear cells. By immunohistochemical stains, the clear cells were completely negative for TTF-1, thyroglobulin, calcitonin and inhibin while equivocally staining for cytokeratin, CD10 and galectin-3. The histologic diagnosis was renal cell carcinoma metastatic to follicular adenoma of the thyroid gland. CONCLUSION: Renal cell carcinoma metastatic to the thyroid may masquerade as a primary thyroid neoplasm. A history of prior nephrectomy, the presence of unremarkable thyroid follicle cells, the absence of a papillary or follicular growth pattern and immunohistochemical study can help differentiating metastatic renal cell carcinoma from a primary thyroid lesion with clear cell change.     

Diagnostic pitfalls in fine needle aspiration cytology of atypical apocrine metaplasia in a breast lesion. A case report

BACKGROUND: Apocrine metaplastic cells are frequently encountered in fine needle aspirates of breast lesions. Atypical apocrine metaplastic cells with signet ring features can also occur, and their presence may present a diagnostic dilemma in the differentiation of benign versus malignant lesions. CASE: A fine needle aspirate of a 2.5 x 1.0-cm, subareolar mass in a 47-year-old female showed atypical cells with signet ring morphology. Also present were clusters of cells that were enlarged and showed nuclear atypia, prominent nucleoli and cytoplasmic granules. Papillary cohesive clusters of ductal cells were also identified. The fine needle aspiration diagnosis was mucinous carcinoma. The nodule was excised, and the histologic diagnosis was sclerosing ductal papilloma with atypical apocrine metaplasia. CONCLUSION: Atypical apocrine cells can be misinterpreted as mucinous carcinoma or usual duct adenocarcinoma on fine needle aspiration cytology. We present clues that may help in rendering the correct interpretation.     

Aspiration cytology of the oncocytic variant of papillary adenocarcinoma of the thyroid gland

OBJECTIVE: To study the cytologic features of the oncocytic variant of papillary adenocarcinoma of the thyroid gland to distinguish this subtype from other oncocytic lesions of the thyroid. STUDY DESIGN: We reviewed the smears from aspiration biopsies of 6 proven cases of oncocytic variant of papillary adenocarcinoma and compared their cytologic features with smears from 19 oncocytic follicular neoplasms (11 adenocarcinomas and 8 adenomas). Smears were stained with a modified Giemsa stain (Diff-Quik). RESULTS: All smears were cellular. Colloid was variable but more abundant in cases of the oncocytic variant of papillary adenocarcinoma. The cells in papillary adenocarcinoma had round to ovoid, overlapped nuclei; prominent intranuclear inclusions; and "grooves." Nucleoli were generally absent. In oncocytic follicular neoplasms, the cells had round nuclei and prominent nucleoli. Nuclear inclusions and grooves were seen but were not as prevalent as in papillary adenocarcinomas. CONCLUSION: The oncocytic variant of papillary adenocarcinoma of the thyroid gland can be distinguished from other oncocytic lesions by fine needle aspiration biopsy, whereas the absence of prominent nucleoli in oncocytes favors the diagnosis of an oncocytic papillary adenocarcinoma.     

Fine needle aspiration biopsy of neuroendocrine breast carcinoma metastatic to the thyroid. A case report

BACKGROUND: Tumors showing neuroendocrine differentiation arise in a wide range of organs, and metastatic neuroendocrine tumors may be difficult to differentiate from primary tumors. This report describes an unusual case of metastatic breast carcinoma with neuroendocrine differentiation that presented as a solitary thyroid nodule. The diagnosis was made by fine needle aspiration biopsy (FNAB). CASE: A 52-year-old woman presented with a thyroid nodule and bilateral enlarged supraclavicular fossa lymph nodes. FNAB revealed a neuroendocrine carcinoma. Further questioning revealed that the patient had had a breast carcinoma resected eight years previously. The diagnosis of metastatic neuroendocrine breast carcinoma was established by immunocytochemistry. The patient received antiestrogen therapy but subsequently developed skeletal metastases. CONCLUSION: Neuroendocrine carcinomas from various sites show similar cytologic features. In this case, a diagnosis of breast carcinoma metastatic to the thyroid was suggested by the clinical history and confirmed by FNAB with immunocytochemistry.     

Papillary carcinoma of the thyroid occurring during pregnancy. Report of a case diagnosed by fine needle aspiration cytology

A case of papillary carcinoma of the thyroid gland occurring during pregnancy in a 29-year-old woman is described. The enlarged thyroid nodule was first detected at 10 weeks of gestation; fine needle aspiration (FNA) of the nodule showed no cytologic evidence of malignancy. Repeat FNA at 30 weeks of gestation produced inadequate material for diagnosis. A final FNA at 38 weeks of gestation showed classic cytologic features of papillary carcinoma, including papillary structures, grooved nuclei and intranuclear cytoplasmic inclusions. After delivery, the patient was treated with total thyroidectomy and cervical lymph node dissection. The enlargement of the nodule in this case during the course of the pregnancy suggests a relationship between pregnancy and the malignant development of thyroid nodules; this is discussed along with the utility of FNA cytology for diagnosing thyroid cancers during pregnancy.     

Fine needle aspiration biopsy of mixed medullary-follicular thyroid carcinoma. A report of two cases

BACKGROUND: Mixed differentiated thyroid carcinomas are rare tumors, difficult to recognize on fine needle aspiration biopsy (FNAB). Most cases are diagnosed only after histologic investigation. CASES: The cases entailed two cytologic samples and a thyroidectomy specimen. Two FNAB thyroidectomy specimens from a 60-year-old man presenting with a solitary thyroid nodule (case 1) were investigated. Both cytologic samples were referred as atypical, with a mixture of features indicating a proliferating follicular lesion but also containing some characteristics of medullary carcinoma. The serum calcitonin level was borderline. Surgery was recommended because of a suspicion of malignancy. The diagnosis of mixed medullary follicular carcinoma was established after a complex histologic investigation. The tumor was encapsulated, with partly microfollicular architecture. Immunohistochemistry was positive for both calcitonin and thyreoglobulin. Electron microscopy from the formol-paraffin block found neurosecretory granules in many cells. The patient was well one year after the operation. One FNAB and thyroidectomy specimen from a 47-year-old woman with long-treated lymphoplasmocellular thyroiditis (case 2) was investigated. The tumor in case 2 was diagnosed on FNAB as medullary carcinoma. Only after histologic and immunohistochemical investigation was mixed differentiation proven. CONCLUSION: Mixed differentiated thyroid tumors are a diagnostic challenge on fine needle aspiration. Irrespective of their rarity, they can be suspected if combined features are present. FNAB recognition of the medullary component in both cases was of crucial importance. Nevertheless, definitive diagnosis remains a histologic problem due to the necessity for topographic information.     

Thyroid metastasis from intraductal papillary-mucinous carcinoma of the pancreas. A case report

BACKGROUND: Intraductal papillary-mucinous carcinoma (IPMC) of the pancreas is a newly identified clinicopathologic entity of the exocrine pancreas. It has been considered a slowly growing and less-aggressive carcinoma with a favorable prognosis. There have been only a few documents reporting its distant metastasis and cytologic features, with no report of thyroid metastasis until the present. CASE: A case of IPMC occurred in a 45-year-old male, who was admitted with rapid growth and tenderness of the thyroid. Abdominal computed tomography showed the typical cystic dilatation of IPMC with adjacent organ metastasis. Fine needle aspiration of the thyroid yielded papillary fronds of carcinoma cells with nuclear pleomorphism, abundant cytoplasm and prominent nucleoli in a mucinous background. Immunohistochemical findings from the skin and thyroid characterized the papillary-mucinous carcinoma as having originated in the pancreas. CONCLUSION: This case suggests that papillary carcinoma fronds aspirated from the thyroid should be further differentiated from the primary site and that a pleomorphic nucleus in a mucinous background is a useful feature to exclude a thyroid origin. Before this, distant metastasis of IPMC to the skin and thyroid has not been reported. The prognosis of IPMC with wide, distant metastasis at an advanced stage is poor.     

Diagnosing invasive cystic hypersecretory duct carcinoma of the breast with fine needle aspiration cytology. A case report

BACKGROUND: Cystic hypersecretory duct carcinoma (CHC) of the breast, first described in 1984, is a rare variant of duct carcinoma. Histologically it is characterized by the formation of dilated ducts and cysts containing an eosinophilic secretory product resembling thyroid colloid. The lining epithelium of the cysts atypically proliferates to form intraductal carcinoma. Only four cases of invasive cystic hypersecretory carcinoma have been reported. CASE: We present a case of invasive CHC with tumor emboli in many lymphatic spaces and axillary nodal metastases. The lesion was also evaluated by fine needle aspiration. Direct smears with Papanicolaou stain were highly cellular and had abundant, intensely staining, orange-to-gray-green thyroid colloid-like material. Epithelial cells, showing a variety of cellular patterns, were indistinguishable from usual ductal carcinoma cells. These cytologic findings may be characteristic enough to suggest cystic hypersecretory carcinoma. CONCLUSION: The cytologic features of CHC are distinctive and correlate with histology. This was the first presentation of colloidlike secretory material in cytologic material with Papanicolaou stain in such a case. Invasive CHC tends to have aggressive behavior. Cystic hypersecretory hyperplasia coexisted in this case.     

Cytologic appearances in invasive lobular carcinoma of the breast. A study of 21 cases

OBJECTIVE: To examine the fine needle aspiration cytologic features of invasive lobular carcinoma of breast and to discuss problems that may occur in cytodiagnosis. STUDY DESIGN: Fine needle aspiration cytologic smears from 21 cases of invasive lobular carcinoma (ILC) of breast were subjected to detailed cytomorphologic analysis. Features studied included pattern of cells, size of cells, nuclear placement, pleomorphism, presence of intracytoplasmic lumina (ICL) and signet ring cells. RESULTS: Cellularity was generally moderate or high, and the pattern was predominantly or partly dissociated in 86% of cases. Rosettelike pattern was discerned in alveolar-type ILC. Cell size was usually small or intermediate, with nuclei placed eccentrically in most cases. ICLs with or without signet ring cells were present in 12 cases (57%). CONCLUSION: A cytologic picture consisting of predominantly dissociated small or intermediate-sized tumor cells with eccentric nuclei, with some of the cells showing ICLs, is highly suggestive of ILC. Indian file pattern, another characteristic feature of ILC, is, however, focal and inconsistent. Variant patterns of ILC may show other cytologic features, such as rosettelike pattern (alveolar variant of ILC) or large cell pattern (pleomorphic variant of ILC) and may consequently be difficult to categorize on cytologic smears.     

Fine needle aspiration biopsy of primary mucinous carcinoma of the skin: a case report

BACKGROUND: Primary mucinous carcinoma of the skin is a rare neoplasm of sweat gland origin. To date there are only 2 case reports in English describing its features on fine needle aspiration biopsy (FNAB). We describe an additional case and review the literature regarding this entity. To the best of our knowledge, this is the first reported case with a sentinel lymph node biopsy. CASE: A 78-year-old woman presented with a 3-cm left scalp mass at an outside institution. Following incomplete excision, multiple subcentimeter nodules developed in the skin adjacent to the biopsy site. FNAB of the nodules confirmed a recurrence of mucinous carcinoma. Clinical examination and extensive radiographic studies did not reveal primary disease elsewhere, thus supporting a diagnosis of primary mucinous carcinoma of the skin. At the time of wide excision of the residual tumor, sentinel lymph node biopsy revealed a single focus of micrometastasis. The patient declined adjuvant therapy and was disease free 6 months after the initial diagnosis. CONCLUSION: Cutaneous mucinous carcinoma is a tumor characterized by bland histocytologic features and abundant extracellular pools of mucin. Without a high index of suspicion, this rare entity may be overlooked or misdiagnosed. Numerous benign and malignant mucin-producing primary and secondary mimics exist, and immunohistochemistry offers limited benefits in differentiating them. Cytologic diagnosis of primary mucinous carcinoma of the skin is possible; however, correlation of clinical, radiologic and pathologic features is necessary to arrive at an accurate diagnosis.     

Fine needle aspiration cytologic findings of micropapillary carcinoma in the lung: a case report

BACKGROUND: Micropapillary carcinoma is a variant of adenocarcinoma described in many anatomic sites and most recently in the lung. The cytologic recognition of this distinct pathologic entity in transthoracic needle aspiration specimens is important in providing prognostic information and therapeutic guidance. CASE: A 58-year-old woman presented with a < 1-cm lesion in the left breast identified on screening mammogram. A core biopsy of this lesion revealed an estrogen and progesterone receptor positive tubular carcinoma. Before a hookwire localization biopsy, a chest x-ray revealed a 1.7-cm spiculated mass in the right lower lobe. The diagnosis of adenocarcinoma with micropapillary features was made by fine needle aspiration cytology (FNAC). The lobectomy specimen showed a combination of adenocarcinoma, papillary adenocarcinoma and micropapillary carcinoma. CONCLUSION: Micropapillary carcinoma is a unique variant of adenocarcinoma, having important clinical associations because of its propensity for angiolymphatic invasion and higher stage at disease presentation. This case demonstrates the cytomorphologic characteristics of micropapillary carcinoma in a transthoracic FNA of the lung.     

Cytologic features of cribriform-morular variant of papillary carcinoma of the thyroid: a case report

BACKGROUND: While the histology of cribriform-morular variant of papillary thyroid carcinoma has been well documented, its appearance on cytologic smears has rarely been described given the rarity of this tumor. CASE: A 28-year-old woman had a neck lump for an unspecified duration for which she sought medical attention. She was previously well, and there was no significant family history of illness. Fine needle aspiration of the thyroid mass disclosed columnar cells with fine to granular chromatin and nucleargrooves associated with papillary fragments and acinar formation. Occasional groups of epithelial cells forming morules, previously unreported on cytology, were present. An excision specimen of the left thyroid nodule revealed morphologic features of cribriform-morular variant of papillary carcinoma of the thyroid. CONCLUSION: A diagnosis of cribriform-morular variant of papillary carcinoma of the thyroid could be established on fine needle aspiration cytology, prompting exclusion of familial adenomatous polyposis and distinguishing it from other, more aggressive variants of thyroid carcinoma, such as columnar cell carcinoma.     

A cytologic perspective on meibomian gland carcinoma

OBJECTIVE: To reevaluate and reestablish the reproducible diagnostic cytomorphologic features of meibomian gland carcinoma (MGCA), demonstrating the importance of fine needle aspiration cytology (FNAC) in eyelid lesions and leading to better management of the tumor. STUDY DESIGN: Cytologic smears ofpreviously diagnosed cases of MGCA over a 3-year period were collected, along with their histopathology reports. The cytomorphology of the histopathologically proven cases were reevaluated in greater detail. The cytologic smears were stained with Leishman-Giemsa cocktail and Papanicolaou stain, and the histopathologic sections were stained with hematoxylin-eosin. Special stains and immunohistochemical stains were applied as required. RESULTS: Of the 19 cases, 3 diagnosed as MGCA on cytologic examination were reported as basal cell carcinoma on histopathology. On reevaluation of the cytologic smears, in addition to the regular characteristic features of MGCA, interesting findings such as an isolated dispersed cell population in a bubbly background, signet ring cells, pseudo-mucin cell balls, giant cell reaction and hyaline-like round bodies were observed. CONCLUSION: This study emphasizes the cytomorphologic features of MGCA in addition to those described in the literature, which could be of a great help in its diagnosis. Further, it emphasizes the importance of FNAC in the diagnosis of MGCA.     

Epithelial-myoepithelial carcinoma of the parotid. A case of ductal-predominant presentation with cytologic, histologic and ultrastructural correlations

BACKGROUND: The cytologic features of the usual type of epithelial-myoepithelial carcinoma (EMC) of the parotid, with myoepithelial cell predominance, is well described in the cytology literature. In contrast, the cytologic features of ductal-predominant-type EMC has not yet been reported. CASE: An 82-year-old male presented with a 2.7-cm parotid mass of two years' duration. Fine needle aspiration smears stained with Diff-Quik showed cohesive tissue fragments outlined by metachromatic fibrils scattered in abundant, smooth, bluish background material. Ultrafast Papanicolaou stain revealed sharply outlined, large ductal cells with smooth, round to oval nuclei, prominent nucleoli and abundant vacuolated cytoplasm; the cells were arranged tridimensionally in occasional follicles that contained thick secretions. Neoplastic myoepithelial cells were occasionally seen at the periphery of tissue fragments, most commonly hidden underneath the neoplastic ductal epithelium at a slightly different focal plane; the cells had small, oval, dark nuclei and inconspicuous cell borders. The nuclear area and cell size of the neoplastic ductal cells was two and three times, respectively, that of neoplastic myoepithelial cells. CONCLUSION: EMC, depending on the ratio of ductal to myoepithelial cell components, has different cytologic presentations. This case illustrates the ductal-predominant presentation of EMC.