Fine‐needle aspiration diagnosis of high grade adenoid cystic carcinoma metastatic to the pancreas

Pancreatic tumors are mostly primary tumors, with only rare metastatic tumors described in the literature. Here we report an unusual case of fine‐needle aspiration (FNA) diagnosis of high grade adenoid cystic carcinoma of the parotid gland metastatic to the pancreas. The aspirate smears were moderately cellular and revealed numerous basaloid neoplastic cells. The cytomorphologic differential diagnosis included primary pancreatic tumor with small cell morphology as well as metastatic tumors. By immunocytochemistry, the tumor cells were positive for cytokeratins (AE1/AE3, CAM5.2, and CK7), and CD117 (C‐KIT), and negative for CD45, WT1, synaptophysin, chromogranin, CD56, TTF‐1, and CK20. The cytomorphologic features and immunoprofile in our case were consistent with high‐grade carcinoma metastases from patient's known salivary gland primary. To the best of our knowledge, this case is the first reported encounter of FNA diagnosis of pancreatic metastasis with small cell morphology from a salivary gland neoplasm as primary site. Diagn. Cytopathol. 2015;43:117–120. © 2014 Wiley Periodicals, Inc.     

Fine-needle aspiration biopsy: Pitfalls in the diagnosis of spindle-cell lesions

Seven cases of spindle-cell proliferations in which fine-needle aspiration biopsy (FNAB) did not correlate with subsequent histology are presented. Three cases were considered low-grade sarcoma, one a dermatofibrosarcoma protuberans (DFSP), one a spindle-cell tumor with malignancy not excluded, and one a rhab-domyosarcoma vs. a fibrosarcoma. Two of the these three were histologically nodular fasciitis and one an inflammatory pseudotumor. Two cases were diagnosed cytologically as fibromatosis or nodular fasciitis (NF). One of these histologically was an intramuscular hemangioma, the other a DESP. The last two cases were diagnosed by FNAB as spindle-cell lesion, undetermined if benign or malignant, and malignant fibrous histiocytoma (MFH). Histologically both of these case were leiomyosarcoma. The cyto-logic features of each case, differential diagnosis, and potential pitfalls are discussed. In the evaluation of FNAB smears dominated by spindle cells, cellullarity, individual cells and cell patterns,and background stromal features coupled with a precise clinical history may allow a narrow differential diagnosis with a focus on whether the lesion is benign or malignant. Caution is warranted in the exact classification of spindle-cell tumors from FNAB as this may have a major impact on patient management. © 1994 Wiley-Liss, Inc.     

EBUS‐FNA of a station seven lymph node: An unusual presentation of a young nonsmoker male with hemoptysis and subcarinal lymphadenopathy

Endobronchial ultrasound‐guided fine needle aspiration (EBUS‐FNA) is a safe and minimally invasive bronchoscopic technique that allows both visualization and cytologic sampling with a high diagnostic yield in a patient with mediastinal lymphadenopathy. Besides the most common indication of staging for a patient with a primary lung carcinoma, EBUS‐FNA can be used to identify benign infectious and noninfectious processes as well as lymphoma and malignancy of unknown primary. Triaging of procured specimen for diagnostic, prognostic, and therapeutic ancillary studies requires appropriate clinical information at the time of rapid on site evaluation (ROSE) of smears. This case report demonstrates a young, previously healthy nonsmoker presenting clinically with cough, hemoptysis, and a 1.7 cm enlarged subcarinal lymph node by imaging. EBUS‐FNA obtained smears from the lymph node revealed a pleomorphic population of smaller cells with a low nuclear to cytoplasmic ratio and prominent nucleoli, and larger cells had nuclei with bizarre shapes, mitoses, multinucleation, enlarged nucleoli, and pigmentation in a background of lymphocytes. The cytomorphologic and immunohistochemical workup of this case confirmed the unexpected diagnosis of metastatic melanoma. This result was a complete surprise to the clinical team managing the patient and prompted a thorough clinical workup. Subcarinal lymphadenopathy with metastatic malignant melanoma as the cause is rare. This case report highlights how ROSE and appropriate triaging of specimen were crucial in appropriately working up this case. We also survey the literature to review the reported unusual presentations of metastatic melanoma. Diagn. Cytopathol. 2015;43:238–242. © 2014 Wiley Periodicals, Inc.     

Leiomyosarcoma metastatic to the orbit: Diagnosis by fine-needle aspiration

A 47-yr-old man with history of metastatic low-grade rectal leiomyosarcoma presented with progressive protrusion of his left eye due to an enlarging orbital mass. The differential diagnosis included tumor metastasis or orbital infection due to an unknown infectious agent. Diagnostic fine-needle aspiration (FNA) of the orbit was performed on an urgent basis to institute proper therapy and to save the patient's eyesight. Cytomorphologic examination of the material demonstrated a spindle-cell neoplasm consistent with metastatic leiomyosarcoma. It is a rare event for leiomyosarcoma to occur in the orbit. On our review of the literature, the cytology of primary orbital leiomyosarcoma on FNA has only been reported once. To our knowledge, this is the first report of the FNA cytomorphology of metastatic leiomyosarcoma to the orbit. Diagn. Cytopathol. 1997;17:369–373. © 1997 Wiley-Liss, Inc.     

FNA diagnosis of retroperitoneal leiomyosarcoma metastasizing to the breast

Fine-needle aspiration (FNA) biopsy is one of the first-line investigations in any breast lump, and hence cytomorphological recognition of nonmammary metastatic tumors to the breast and their distinction from primary tumors is important. Breast metastasis from extra-mammary malignancy is rare, constituting 2% of breast tumors; even rarer are metastatic leiomyosarcomas. Our patient presented with a breast lump 2 years after operative removal of a retroperitoneal leiomyosarcoma. The breast lump was confirmed to be a metastasis from the earlier primary. Herein, we report the first case of a retroperitoneal leiomyosarcoma metastatic to the breast diagnosed by Fine Needle Aspiration.     

Malignant thymic neoplasms: diagnosis by fine-needle aspiration biopsy with histologic, immunocytochemical, and ultrastructural confirmation

Two cases of malignant thymic neoplasms diagnosed by transthoracic fine-needle aspiration (FNA) biopsy under fluoroscopic and computerized axial tomography (CT) guidance with histologic, immunocytochemical, and ultrastructural confirmation are presented. The clinical and cytomorphologic features of the first case were typical of a malignant thymoma. A characteristic biphasic cell population of benign epithelial cells and mature lymphocytes was seen in Diff-Quik- and Papanicolaou-stained smears from the anterior mediastinal mass and the paravertebral metastasis and was confirmed by histologic examination. Immunoperoxidase studies for T and B cell subsets demonstrated lymphocytes with the thymic lymphocyte phenotype (Leu 6). Electron microscopic (EM) examination revealed epithelial cells with desmosomal attachments, tonofilaments, and extended cell processes along with mature lymphocytes. FNA biopsy of the second case demonstrated features of a thymic carcinoma. Individually scattered and loosely clustered small groups of markedly anaplastic and pleomorphic large cells were seen both in the Diff-Quik- and Papanicolaou-stained smears. EM performed on the FNA specimen demonstrated the poorly differentiated epithelial nature of the malignancy. The mediastinal mass was partially resected and demonstrated an undifferentiated carcinoma staining positively for low-molecular-weight cytokeratin. Ultrastructure demonstrated cell attachments and relationships consistent with carcinoma. The lack of a lung or other extrapulmonary primary tumor was consistent with a thymic carcinoma. These cases demonstrate the value of performing EM and immunocytochemistry on material obtained by fine-needle aspiration, which can aid in establishing the correct diagnosis and facilitate the clinical management of patients with malignant thymic neoplasms.     

Fine-needle aspiration of soft tissue leiomyosarcoma: an analysis of the most common cytologic findings and the value of ancillary techniques

This study aims to determine the diagnostic accuracy of fine-needle aspiration cytology (FNAC) of primary leiomyosarcoma (LMS) of soft tissue and to review diagnostic criteria and adjunctive methods, which can contribute to a confident diagnosis.We evaluated the preoperative FNAC in 89 patients with primary LMS for the following: cytomorphology and correspondence of FNA to histological features of excised tumors and clinical data. In addition, the utility of adjunctive techniques was analyzed and other spindle-cell lesions in the differential diagnoses were discussed.An unequivocal, malignant diagnosis was rendered by FNAC in 78 cases; 74 tumors were diagnosed as sarcoma, of which 31 as LMS or suspicion of LMS. In addition, three smears were labeled as malignant tumor, one as carcinoma metastasis, and three as neurilemmoma. Seven aspirates were inconclusive and one insufficient. On reevaluation, the diagnostic smears in most cases contained tumor cell fascicles with an admixture of dispersed cells or stripped nuclei. The most common cells were spindle cells with elongated, blunt-ended, segmented or fusiform nuclei, and round/polygonal cells, often with rounded or indented nuclei. In addition, 51 cases showed pleomorphic, often multinucleated cells. Osteoclasts, intranuclear vacuoles, and mitoses occurred in 14, 47, and 27 cases, respectively. Thus, most high-grade LMSs have cytologic features that allow diagnosis of sarcoma. Ancillary studies can confirm the diagnosis of LMS and help in the correct interpretation of predominant spindle-cell or epitheloid-cell smears resembling neurilemoma or carcinoma, respectively.     

Fine-needle aspiration cytology of extramammary neoplasms metastatic to the breast

Fine-needle aspiration (FNA) biopsy is the first-line investigation in any breast lump and hence cytomorphological recognition of nonmammary metastatic tumors to the breast and their distinction from primary tumors is important.Metastatic breast neoplasms diagnosed over a 6-yr period from 1997 to 2002 were retrieved from the database of the Department of Cytopathology and the clinical, cytopathological, histochemical, and immunohistochemical findings were correlated with the histopathology of the primary tumor.Fifteen cases of metastatic breast neoplasms were encountered constituting 1.47% of all malignant tumors of the breast diagnosed on FNA. There were 14 female patients and one male patient aged 13-80 yr. The preaspiration clinical diagnosis was either a benign breast lump or a malignancy (primary vs. metastatic). The breast lump was the initial presentation in four cases and the cytodiagnosis of a metastatic malignancy lead to the subsequent detection of the primary malignancy. These included one case each of melanoma, myeloma, rhabdomyosarcoma, and small-cell carcinoma of the lung. There were five pediatric cases that included four cases of rhabdomyosarcoma and one case of leukemic deposit. The adult cases included two cases each of melanoma, small-cell carcinoma, and myeloma; one case of choriocarcinoma; and three cases of soft-tissue sarcomas. These included two cases of malignant fibrous histiocytoma (MFH) and one case of leiomyosarcoma.The presence of unusual cytomorphological patterns on breast FNA should alert the cytopathologist to the possibility of a metastatic breast neoplasm, even if not suspected clinically. A detailed history of the patient, clinical correlation, and immunocytochemistry helps in establishing an accurate diagnosis, which avoids unnecessary surgery and ensures appropriate treatment.     

Hyalinizing clear-cell carcinoma of salivary glands in fine-needle aspiration

Hyalinizing clear-cell carcinoma (HCCC) is a recently described distinctive salivary gland neoplasm. Because of its cytoplasmic clearing and the bland nuclear features, HCCC resembles other tumors. The authors describe the cytomorphologic features of four cases of HCCC in fine-needle aspirates (FNA) and discuss the differential diagnosis. Fine-needle aspirates from 4 patients with primary HCCC of minor salivary glands were reviewed. Smears were stained with Diff-Quik and Papanicolaou stains. The cytologic features of the epithelial and the stromal components were analyzed. Cell blocks were prepared, and findings were correlated with prior or subsequent surgical specimens in each case. The smears contained numerous cohesive small and large epithelial cell groups and sheets which had sharp outlines and showed focal nuclear overlapping. The cells had uniform round to ovoid nuclei, granular chromatin, and small nucleoli. The abundant, well-defined cytoplasm was clear in many cells but denser in others. No myoepithelial cells or hyaline globules were identified. HCCC seems to have characteristic cytomorphologic findings on FNA smears. Because these cytologic features are not specific, and overlap with those of a number of salivary gland neoplasms that contain clear cells, a high level of suspicion, clinico-pathologic correlation, and examination of cell blocks are necessary to suggest the diagnosis. A diagnosis of HCCC by FNA was suspected in 3 of the 4 cases reported here.     

Diagnostic clues for differentiating Merkel cell carcinoma from lymphoma in fine-needle aspiration cytology

Nodal fine needle aspiration (FNA) is usually the first procedure in the work-up of malignancy of unknown primary. Merkel cell carcinoma (MCC) is an aggressive cutaneous cancer more common in Caucasians but rare among Asians. It is a diagnostic challenge in evaluating FNA from a metastatic MCC without the knowledge of a current or prior history of skin cancer. We report the case of a Taiwanese male with cervical and axillary masses. The diagnosis of the FNA from the axillary lymph node was lymphoproliferative lesion suspicious for lymphoma. The histopathological evaluation of nodal biopsy revealed a metastatic neuroendocrine carcinoma and the subsequent excision of the right palm tumor confirmed MCC. Retrospective review of the FNA and imprint cytology smears of the nodal biopsy showed nuclear molding, Indian filing and rare cytoplasmic pale bodies, but no lymphoglandular bodies. Cytologically metastatic MCC may mimic small round cell tumor including lymphoma, we consider these three cytological features as additional diagnostic clues for metastatic MCC. In this report, we present the cytologic and pathological features of this metastatic MCC and discuss the differential diagnosis of the cytologic mimickers.     

Thyroid tumors: cytomorphology of medullary, clinically anaplastic, and miscellaneous thyroid neoplasms

Of 2,012 fine-needle aspirations (FNAs) of the thyroid performed between the years 1984 and 1988, detailed cytomorphologic analysis of 95 cases diagnosed as neoplastic on histology and/or cytology and those that received an equivocal cytodiagnosis are presented in this article. Discussed are medullary thyroid carcinomas (nine cases), clinically anaplastic thyroid tumors (CATT; eight cases), two cases of non-Hodgkin's lymphoma (NHL), and one primary leiomyosarcoma of the thyroid, for a total of 20 cases. Included in the category of CATT are all the thyroid tumors presenting clinically with an anaplastic growth pattern. The cytomorphology of these tumors varied, but the giant- and spindle-cell pattern was predominant. An accurate cytodiagnosis was possible, as per cytohistologic correlation, in seven cases, while in one case histological material was not available for study. Medullary carcinoma of the thyroid (MCT) showed a mixed spindle-cell and round-cell population in eight cases and an entirely spindle-cell population in one case. All cases of MCT were correctly diagnosed on cytology, and amyloid could be demonstrated in the cytologic smears in three cases. The cases of NHL and leiomyosarcoma could also be correctly interpreted on cytology.     

Hepatocellular carcinoma-fibrolamellar variant: cytopathology of an unusual case

The fibrolamellar variant of hepatocellular carcinoma (FL-HCC) is an uncommon visceral malignancy with a distinctly better prognosis. An accurate initial diagnosis, therefore, is essential for prognostic and therapeutic reasons. This case report describes the cytomorphology of an unusual case of FL-HCC in a 13-yr-old boy who was found to have a hepatic mass with prominent intraluminal growth pattern seen predominantly in the right hepatic duct. A diagnosis of FL-HCC was originally suspected on bile duct brushings obtained during endoscopic retrograde choleangiopancreaticogram (ERCP) and subsequently confirmed on fine-needle aspiration (FNA) and surgical resection of the hepatic tumor. The cytomorphologic profile of FL-HCC is distinctive in the right clinical setting, allowing an accurate preoperative identification of this malignancy on biliary brushing or FNA.     

Fine-needle aspiration cytology of benign and malignant adenomyoepithelioma: report of two cases.

Cytological features of a malignant spindle-cell variant and a benign tubular variant of adenomyoepithelioma were examined to improve diagnosis of this tumor. Fine-needle aspiration cytology, of both a malignant and a benign case, characterized cellular and cohesive cell clusters composed of epithelial and myoepithelial cells. The smears of the malignant case were rich in spindle-shaped myoepithelial cells, admixed with a few epithelial cells. In about a fourth of the clusters, atypical cells with enlarged hyperchromatic nuclei and prominent nucleoli comprised more than 20% of cells. The smears of the benign case were composed of tubular epithelial cells surrounding one to several layers of myoepithelial cells with clear cytoplasm. Mild atypia was occasionally noticed. A review of the literature showed that a cytological diagnosis of malignancy is not warranted, if nuclear atypia is not generally severe. Focal severe atypia is not definitively indicative of benignity or malignancy.     

CD10 facilitates the diagnosis of metastatic renal cell carcinoma from primary adrenal cortical neoplasm in adrenal fine-needle aspiration

Renal cell carcinoma (RCC) frequently metastasizes or invades the adrenal gland. Metastatic RCC is often difficult to differentiate from primary adrenal cortical neoplasm (ACN) in an adrenal fine-needle aspiration (FNA). Recently, CD10 immunoreactivity was observed in more than 90% of RCC, but none in primary ACN. To facilitate the accurate diagnosis of metastatic RCC in adrenal FNA, we retrospectively studied the cytomorphology and CD10 immunohistochemistry in 20 cases of FNA specimens, including 10 cases of adrenal FNA (six cases of metastatic RCC and four cases of primary ACN) and 10 cases of primary RCC. Cytomorphologically, several overlapping features were observed between primary ACN and metastatic RCC, including: abundant clear cytoplasm, often with microvesicles, large nuclei with prominent nucleoli, bare nuclei, and prominent vascularity. Immunostaining for CD10 was positive in 9/10 cases of primary RCC, 5/6 cases of metastatic RCC in the adrenal gland, and 0/4 cases of primary ACN. Our study indicates that: 1) an accurate diagnosis of ACN in FNA specimens can often be difficult due to overlapping cytomorphologic features with RCC, and 2) CD10 immunostaining is helpful in separating metastatic RCC from a primary ACN and can reliably be performed on a cytologic sample.     

Fine-needle aspiration cytology of metastatic small cell carcinoma of the colon: A report of three cases

Small cell carcinoma of the large intestine is a rare, extremely aggressive malignancy often associated with an overlying adenoma. We report three cases of metastatic small cell carcinoma of the colon diagnosed by fine-needle aspiration (FNA) biopsy. Two of the patients were women (ages 33 and 46 yr old) and one was a man (69 yr old). FNA biopsy established the diagnosis of metastatic small cell carcinoma involving the liver (2 cases) and soft tissue of the scapular region (1 case). In one patient, the FNA diagnosis of hepatic metastases preceded identification of the primary site. Subsequently, the patient was found to have a small cell carcinoma subadjacent to a colonic villous adenoma, illustrating the importance of investigating villous lesions of the colon in patients with metastatic small cell carcinoma of unknown primary origin (especially in non-smokers). All three cases showed the characteristic cytologic features of small cell carcinoma. Ancillary studies performed on aspirated material confirmed the diagnosis of small cell carcinoma in one case. Immunocytochemical studies revealed punctate cytokeratin and diffuse neuron-specific enolase (NSE) positivity of the malignant cells. Ultrastructurally neurosecretory granules were evident. To the best of our knowledge, this is the first FNA cytologic report of metastatic small cell carcinoma of the large intestine. This FNA report also demonstrates when a small cell carcinoma is detected in a metastatic site in a patient lacking a lung primary, a likely primary site could be adjacent or beneath a polypoid lesion of the colon. Diagn Cytopathol 1996;15:54–59. © 1996 Wiley-Liss, Inc.     

Spindle-cell lesions of the mediastinum: Diagnosis by fine-needle aspiration biopsy

Spindle cells seen in fine-needle aspiration biopsy (FNAB) of the mediastinal lesions can be a component of a wide variety of benign and malignant conditions. Few of these conditions, however, are described in the FNA cytopathology literature. This review discusses the cytopathologic features, differential diagnoses, and potential pitfalls of a variety of lesions with a significant component of spindle cells encountered in mediastinal FNAB. The cytopathology files from four institutions were searched for cases of mediastinal FNAB containing a spindle-cell component that was a key or predominant cytologic feature of the diagnostic specimen. The cytomorphologic features of these cases were analyzed, and their differential features are discussed. Of 196 mediastinal FNABs, 22 (11%) were lesions with significant spindle-cell component: granulomatous inflammation (four); benign nerve sheath tumor (four); thymic cyst (two); spindle-cell thymoma (two); large-cell non-Hodgkin's lymphoma with sclerosis (two); nodular sclerosing Hodgkin's disease (two); liposarcoma (two); spindle-cell squamous carcinoma possibly arising in a teratoma (one); unspecified high-grade sarcoma (one); spindle-cell malignant melanoma (one); and nonspecific fibrous tissue (one). The cytologic features of each lesion were analyzed as an aid for accurate classification. These findings were correlated with radiologic and clinical information when available. The value of ancillary studies performed on aspirated material in selected cases was also reviewed. FNA of mediastinal lesions with significant spindle-cell morphology represents an infrequent and heterogeneous group of entities that may pose significant diagnostic challenges. This review presents the salient cytopathologic features of various spindle-cell lesions of the mediastinum with particular emphasis on differential diagnosis and pitfalls. The pathologist must use caution when interpreting these lesions and ancillary studies may be of significant value in selected cases. Diagn. Cytopathol. 1997;17:167–176. © 1997 Wiley-Liss, Inc.     

Fine-needle aspiration cytology of amyloid associated with nonneoplastic and malignant lesions

To assess the value of fine-needle aspiration (FNA) cytology for the diagnosis of amyloid, we retrospectively studied all FNA cases diagnosed as having amyloid during a 6-yr period (1990–1996). FNA was performed on both superficial and deep locations. A total of 6 cases containing amyloid was studied, including primary medullary thyroid carcinoma, metastatic medullary thyroid carcinoma to a vertebrae, multiple myeloma, squamous-cell carcinoma of the lung metastatic to a hilar lymph node, primary pulmonary amyloid, and amyloid tumor in a vertebral body in a patient with primary systemic amyloidosis. Despite the location or disease association, the cytologic appearance of amyloid in all cases was similar. On Diff-Quik stain, amyloid appeared as amorphous, irregular, waxy, basophilic to metachromatic clumps of material. Papanicolaou stain revealed cyanophilic to organophilic clumps of material with occasional prominent fissures. In all 6 cases, amyloid was confirmed by Congo red stain and in 3 cases by a thioflavin T stain. In 4 of the 6 cases (67%), amyloid was associated with an underlying malignancy. In 3 cases malignant cells were admixed with the amyloid, and in another case malignancy was present at a distant site. We conclude that FNA biopsy is a helpful initial procedure for the evaluation of patients with amyloid deposits. The clinical implications of amyloid found in any particular body site include both benign and malignant conditions. The presence of an associated neoplasm must be especially considered in the differential diagnosis of amyloid deposits. Diagn. Cytopathol. 1998;18:270–275. © 1998 Wiley-Liss, Inc.     

Metastatic breast carcinoma involving the thyroid gland diagnosed by fine-needle aspiration: a case report

Secondary involvement of the thyroid gland from a remote primary malignancy is uncommon. The distinction of metastatic carcinoma (MC) or sarcoma from a primary thyroid malignancy is important because the treatment is different. We discuss a case of a 64-yr-old female with a history of breast carcinoma, who presented with pain and swelling in her neck 5 yrs after being diagnosed with breast cancer. She had undergone mastectomy with subsequent chemotherapy and radiation for infiltrating mammary carcinoma. During the 5-yr interval, she had been free of clinically evident metastatic disease. Subsequent work-up revealed two distinct nodules in the left lobe of her thyroid gland as well as a subcutaneous mass in her right shoulder. A fine-needle aspiration (FNA) of the larger thyroid nodule showed malignant epithelial cells with features consistent with breast carcinoma in a background of benign thyroid epithelial cells and colloid. The case was signed out as metastatic breast carcinoma. Subsequent FNA and biopsy of her right shoulder lesion also revealed metastatic breast carcinoma with similar morphology to the material in the thyroid FNA.     

Fine-needle aspiration of neurilemoma (schwannoma). A clinicocytopathologic study of 116 patients

The preoperative fine-needle aspiration cytology (FNAC) diagnoses in 116 surgically excised neurilemomas were reviewed and compared with the corresponding histopathologic diagnoses made on surgical specimens and with clinical data. In addition, the utility of adjunctive techniques was analyzed and other spindle-cell lesions in the differential diagnoses were discussed. An unequivocal, benign diagnosis was rendered by FNAC in 80 cases, 67 of which were correctly labelled as neurilemoma in a review of the original cytology reports. There were 6 false-positive malignant diagnoses while 23 smears were considered insufficient and 7 inconclusive as to whether benign or malignant. On reevaluation, the diagnostic smears in most cases contained spindle cells with wavy nuclei embedded in a fibrillar, occasionally collagenous, and/or myxoid matrix and Antoni A/Antoni B tissue fragments. A moderate to abundant admixture of round to oval cells was also frequent. Nuclear palisading was seen in 41 smears with distinctive Verocay bodies in 10. Markedly pleomorphic nuclei were seen in smears from 8 ancient and 6 conventional neurilemomas, and slight to moderate nuclear pleomorphism was observed in 38 additional cases. Thus most neurilemomas have distinct cytomorphologic features that allow correct diagnosis. The major problem in FNAC of neurilemoma is to obtain sufficient material. Furthermore aspirates showing predominantly Antoni A features, nuclear pleomorphism, and/or myxoid changes can easily be confused with other types of benign or malignant soft-tissue tumors.