Fine needle aspiration biopsy of the parotid gland. Diagnostic problems and 2 uncommon cases

OBJECTIVE: To describe the diagnostic problems and present our findings in 2 uncommon tumors, malignant myoepithelioma and small cell undifferentiated carcinoma, by examining fine needle aspiration (FNA) biopsies of parotid gland masses. STUDY DESIGN: The study group consisted of 34 females and 41 males 12-80 years old, with an average of 44. Excluding inflammatory results, all adequate aspirates were confirmed histologically to determine the correlation. RESULTS: Sensitivity of FNA cytology was 91%, with specificity of 98%. We encountered some difficulties, and therefore misdiagnoses, in evaluating specific neoplasms, such as adenoid cystic carcinoma and Warthin's tumor, which have well-established cytologic diagnostic criteria. Two cases of uncommon neoplasms of salivary glands, small cell undifferentiated carcinoma and malignant myoepithelioma, were cytologically found to be malignant but not further classified. In addition, tuberculous parotitis, with its well-defined features, should to be referred since unnecessary surgery can be avoided by using FNA cytology. CONCLUSION: FNA is a sensitive and specific diagnostic tool for parotid gland masses. However, specific classification of neoplasms may sometimes be difficult. Pathologists should be aware of specific entities, such as malignant myoepithelioma, when evaluating high grade neoplasms.     

Cytomorphology of lipomatous tumors of soft tissue

OBJECTIVE: To evaluate the cytomorphologic features of benign and malignant lipomatous tumors of soft tissue on fine needle aspirates (FNA) and determine if the variants of liposarcoma could be identified. STUDY DESIGN: FNA of histologically documented benign (51 cases) and malignant (39 cases) lipomatous tumors were reviewed. Twenty-six of the 51 FNA from lipomas and 34 of the 39 FNA from malignant lipomatous tumors were satisfactory for evaluation. RESULTS: FNA from 26 cases of lipomas were cellular, with lobulated, fibroadipose tissue. Thin and thick capillaries were seen in 92% and 65% of cases, though a chicken wire vascular pattern was seen in only 4 cases (15%). A cytodiagnosis of liposarcoma could be made in 23 cases (88%), and these could be further subtyped into well-differentiated (4 cases), myxoid (8), pleomorphic (4), round cell (3) and liposarcoma, ?type (4). Only 50% of the well-differentiated liposarcomas, 3 of the 10 pleomorphic liposarcomas and 8 of the 17 myxoid liposarcomas were diagnosed as such on FNA. Cytologic diagnosis of the remaining 9 cases of myxoid liposarcoma were pleomorphic liposarcoma (1); liposarcoma, ?type (3); malignant mesenchymal tumor (1); suspicious for malignancy (2); and benign (2). There were no false positives, but there were 3 false negative cases (1 well-differentiated and 2 myxoid liposarcoma). CONCLUSION: Lipomas can be diagnosed readily. Arborizing vessels can be seen in lipomas and should be interpreted with caution. Subclassification of liposarcomas on FNA is possible but not very reliable. Myxoid liposarcomas pose a problem, and aspirates from them can mimic a wide range of morphologic subtypes. The role of FNA in identification of variants of liposarcoma is limited.     

Cytopathologic findings in breast masses in men with HIV infection

OBJECTIVE: To report the cytologic findings on 15 men with HIV infection who presented with breast masses and underwent fine needle aspiration (FNA). STUDY DESIGN: The cytopathology files of The Johns Hopkins Hospital (JHH) and the University of Texas Southwestern Medical Center (UTSW) were searched for cases of men with breast masses evaluated by FNA. The HIV status of these men was then ascertained. A total of 15 cases (9 at JHH, 6 at UTSW) of 259 (5.79%) were identified in which the patient was HIV seropositive. The pathologic diagnoses were reviewed, and the clinical history, along with the medication list at the time of FNA, was determined. RESULTS: The men ranged in age from 12 to 51 years (mean, 38). Breast masses were present on either the right (n = 6) or left (n = 7) side or were bilateral (n = 2). In all 15 cases, the masses were retroareolar, firm and tender. FNA showed a ductal and stromal proliferative process, often with focal cytologic atypia and numerous background naked myoepithelial nuclei, features consistent with a diagnosis of gynecomastia. Thirteen of these men were on drug regimens, which included indinivir, stavudine and saquinivir. Two of the men were on azidothymidine only. CONCLUSION: Gynecomastia, although rare in young men, was the sole cause of breast masses in HIV-seropositive men in this study. It has been described as an extremely rare side effect of certain antiretroviral medications, including indinivir, stavudine and saquinivir. FNA is an important tool in determining the benign nature of these lesions and excluding other causes of breast masses in this patient population, such as infections, malignant lymphoma and breast carcinoma.     

Value of fine needle aspiration cytology in the diagnosis of testicular neoplasms

In 403 patients with a clinical suspicion of a testicular neoplasm, fine needle aspiration (FNA) was performed on the scrotal mass in 380 cases and on an extrascrotal swelling in 23 cases. There were 109 unsatisfactory aspirates. Fluid was aspirated in 50 cases, and only normal testicular elements were obtained in 82 cases. The aspirate showed an inflammatory lesion in 104 cases. A diagnosis of malignancy or suspicious for malignancy was given in 52 and 6 cases, respectively. Histopathologic confirmation of malignancy was available for 30 cases, for which the aspirate had been reported as malignant in 23, suspicious for malignancy in 3, unsatisfactory in 2 and negative for malignancy in 2. There were no false-positive FNA cytodiagnoses. No local seeding of tumor by the FNA procedure was observed. Typing of the testicular tumors on the aspirates showed a problem in classifying teratocarcinomas.     

Fine needle aspiration (FNA) cytology of adenoid cystic carcinoma and adenomyoepithelioma of breast: two lesions rich in myoepithelial cells

Adenoid cystic carcinoma and adenomyoepithelioma are relatively rare, but well described, breast lesions. The FNA cytology features in two cases of mammary adenoid cystic carcinoma and two cases of adenomyoepithelioma are described. In both cases of adenoid cystic carcinoma, aspirates consisted of tightly cohesive clusters of cells arranged around spheres and interconnecting cylinders of acellular material. The two aspirates of adenomyoepithelioma were composed of large tightly cohesive clusters of cells associated with small amounts of stromal material. In all four aspirates a dual population of epithelial and myoepithelial cells could be identified within cellular aggregates, and numerous bare nuclei were present. Histology revealed the characteristic features of adenoid cystic carcinoma and adenomyoepithelioma. Immunohistochemical staining of histological sections for S‐100 protein and alpha‐smooth muscle actin confirmed the presence of large numbers of myoepithelial cells within all four lesions, providing indirect evidence that bare nuclei in breast aspirates represent myoepithelial cells. The presence of a dual population of epithelial and myoepithelial cells and of numerous bare nuclei within a breast aspirate is generally indicative of a benign lesion. This is not always the case, as adenoid cystic carcinoma is a malignant tumour, and adenomyoepithelioma, while generally exhibiting benign behaviour, is capable of local recurrence and distant metastasis.     

Sensitivity and specificity of fine needle aspiration cytology in the diagnosis of tumors of the thyroid gland

A study of the preoperative fine needle aspiration cytologies in consecutive patients with primary malignant tumors (203 cases) or benign thyroid tumors (217 cases) showed a sensitivity of 0.57 and a specificity of 0.98. The sensitivity of FNA cytology in medullary and undifferentiated carcinomas was 0.82 and 0.84, respectively; none of these were microscopically misdiagnosed. The sensitivity was only 0.58 for papillary carcinomas (excluding occult carcinoma) and 0.42 for follicular carcinoma. Four reasons for these low sensitivities were identified: tumors missed at aspiration, microscopic misinterpretations, diagnoses of cellular atypia and indeterminate diagnoses. Reevaluation of the false diagnoses once more emphasized the problem of distinguishing follicular adenomas from follicular carcinomas. Microscopically undiagnosed papillary carcinomas were either the result of misinterpretations of the characteristic cytomorphologic features or of the smears being misdiagnosed as showing cellular atypia when papillary formations were missing and only one or two of the other cellular criteria were evident. The specificity of FNA cytology of thyroid tumors was found to be high enough to permit surgical intervention after a cytodiagnosis of malignancy.     

Fine needle aspiration cytology of neoplasms metastatic to the breast

The fine needle aspiration (FNA) cytologic findings in 18 cases of metastatic neoplasms of the breast are reported. The cases were encountered in a combined series of 2,529 FNA breast biopsies, of which 666 were malignant; the metastatic neoplasms of the breast thus constituted 2.7% of all the malignant breast tumors. The series consists of 15 women and 3 men, with a mean age of 48 years (range of 11 to 73 years). Sixteen biopsies confirmed metastatic malignancy in patients with known extramammary primaries; the prebiopsy clinical diagnoses in six of the patients were benign breast lesions. In eight patients, the clinical differential diagnosis was either a benign or malignant primary breast lesion versus a metastatic malignancy. In two additional patients, the FNA biopsy identified metastatic neoplasms from unsuspected extramammary primaries. The metastatic neoplasms included three small-cell carcinomas of the lung, one squamous-cell carcinoma of the lung, two malignant melanomas, three ovarian malignancies, including a dysgerminoma, and one each of carcinoma of the fallopian tube, endometrial carcinoma, transitional-cell carcinoma of the urinary bladder, prostatic carcinoma, acute granulocytic leukemia, lymphoma, mycosis fungoides, hepatoma and neuroblastoma of the retroperitoneum. Recognition of unusual cytologic patterns raised the suspicion of, or confirmed the diagnosis of, malignancy in all cases, with no false-negative diagnoses. None of the cases were cytologically interpreted as a primary breast malignancy. Ancillary studies performed on the FNA material, including immunocytochemistry, contributed to a definitive diagnosis in three cases. FNA diagnosis of metastatic malignancy of the breast is essential in order to avoid unnecessary mastectomy and to ensure appropriate chemotherapy and/or irradiation treatment.     

Fine needle aspiration cytology of solitary fibrous tumours of the pleura

OBJECTIVE: To analyse fine needle aspirates from solitary fibrous tumour (SFT) of the pleura and to elucidate the cytological features unique to these tumours and differential diagnostic findings of benign and malignant SFTs. METHODS: Fine needle aspiration (FNA) cytology slides from eight cases of SFT of the pleura, including six benign and two malignant SFTs, were reviewed. The subsequent histological slides were also examined. RESULTS: Cytological diagnoses from six histologically proven cases of benign SFTs were low-grade sarcoma (one), non-small cell carcinoma (one), malignant tumour (1) and benign (three). Two cases of malignant SFTs were cytologically diagnosed as malignancy. The aspirates showed a varying degree of cellularity. Most smears were composed of single, scattered fusiform cells, and irregular loose aggregates of oval to spindle cells intimately admixed with dense collagenous stroma. Two malignant SFTs had a greater number of cells in clusters, and displayed mitotic activity, without significant cytological atypia. CONCLUSIONS: The diagnosis of SFT may be suggested by a combination of cytological and radiological findings. The precise determination of malignancy for SFT, however, is not usually straightforward on the basis of cytological features alone. The findings of highly cellular clusters and mitotic activity in the FNA cytological smear can help differentiate malignant from benign SFTs.     

Metastatic tumors in fine needle aspiration biopsy of the thyroid

A series of almost 25,000 thyroids examined by fine needle aspiration (FNA) biopsy was reviewed to ascertain the incidence and presentation of metastatic cancers in thyroid FNA samples. Metastatic cancers in FNA samples from the thyroid were identified in 25 cases (0.1%); the primary tumors were carcinomas of the kidney (8 cases), lung (7 cases), breast (5 cases), cervix uteri (1 case) and colon (1 case) and 1 case each of malignant melanoma, malignant pleural mesothelioma and rhabdomyosarcoma. FNA cytology was positive in all 25 cases. In 11 cases, the primary tumor was clinically known at the time of FNA biopsy; of the other 14 cases, cytology suggested that the malignancy was metastatic in only 5. Metastases of renal and mammary adenocarcinomas were almost indistinguishable from follicular and papillary thyroid carcinomas on cytologic grounds. The results demonstrate the rarity of this finding and the difficulty of diagnosing a metastatic tumor in the thyroid by FNA biopsy, in the absence of a clinical history of a prior primary neoplasm.     

Inflammatory myofibroblastic tumor of the breast. A case report

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) of the breast is a very rare tumor like lesion with only 6 previously reported cases. Very little is known about the cytology of IMT. We present the fine needle aspiration (FNA) cytology of a case of recurrent, bilateral IMT of the breast and detail the clinical course, radiologic findings, morphologic appearances and immunohistochemical profile of the lesion. CASE: A 79-year-old female was initially seen in 1991 because of a suspicious mammographic abnormality in her right breast. Ultrasound-guided FNA cytology showed an unusual "inflammatory" lesion with occasional aggregates of cellular connective tissue fragments, sheets of uniform ductal epithelial cells with myoepithelial cells, spindle cells, lymphocytes and histiocytelike cells. The lesion was excised, and histology confirmed a benign process with spindle cells, lymphocytes and histiocytes. No malignant features were noted. During follow-up many new lesions appeared in both breasts, and after several FNA procedures and local excisions, bilateral mastectomy was performed at the patient's urging. She remained disease free. CONCLUSION: Although IMT of the breast has benign cytology and histology, clinically and on imaging, it resembles carcinoma. Awareness of the condition may help prevent a false diagnosis of carcinoma.     

Peripheral endothelial cells are not reliable in differentiating primary benign and malignant hepatocellular lesions in fine needle aspirates of the liver

The distinction of hepatocellular carcinoma (HCC) from benign lesions of the liver in fine needle aspiration (FNA) specimens can be problematic. In an attempt to separate well-differentiated HCC from benign hepatocellular lesions, the presence of tissue fragments displaying peripheral endothelial cells (PE) has been proposed in a previous study as a useful feature in favour of malignancy. In this study, we evaluated slides from 59 cases of liver masses undergoing FNA (19 HCC, 40 benign) and evaluated them for the presence of tissue fragments containing PE. We found that 90% of cases of HCC contained tissue fragments in which PE were either focally present or abundant. However, 68% of cases containing only benign hepatocytes also contained tissue fragments in which PE were at least focally present. In addition, it appears that within the group of benign lesions, the presence of PE was related to the overall cellularity of the specimen rather than the specific nature of the lesion. Thus, the presence of PE in tissue fragments does not, in isolation, appear to be a useful morphological feature for the separation of benign and malignant hepatocellular lesions in FNA material.     

Statistical analysis of fine needle aspiration cytology of the breast. A review of 678 cases plus 4,265 cases from the literature

Between 1979 and 1984, 678 breast fine needle aspiration (FNA) cytologic specimens were received in our laboratory; tissue follow-up was available for 159 cases (23%). The diagnoses rendered in cases with subsequent tissue study were benign (41%), insufficient (10.5%), atypical and/or suspicious for carcinoma (10.5%) and malignant (38%). Using the tissue diagnosis as the standard, there were four false-negative cytologic results and one false-positive result. Considering only cases with a definitive diagnosis of benign or malignant, the sensitivity of cytologic interpretation for diagnosing malignancy on adequate material was 94% while the specificity was 98%; the overall efficiency of the test was thus 96%. The predictive values were 98% for a positive test and 94% for a negative test. Of the total number of submitted cases, a correct and definitive diagnosis was rendered 76% of the time. Calculation of similar statistics from six other series in which the FNA cytologic diagnoses were compared with the histologic diagnoses yielded data almost identical to our findings. The high degree of uniformity in the data indicates that these statistical parameters can be used as standards for evaluating the efficiency of breast FNA cytology.     

Learning vector quantizer in the investigation of thyroid lesions

OBJECTIVE: To investigate the capability of the learning vector quantizer (LVQ) in the discrimination of benign from malignant thyroid lesions. STUDY DESIGN: The study was performed on May-Grünwald-Giemsa-stained smears taken by fine needle aspiration (FNA). Using a custom image analysis system, 25 features that describe the size, shape and texture of approximately 100 nuclei were measured from each case. Statistical features were extracted from each case, and a linear regression analysis was performed to detect the statistically significant features. The cases were distributed by category, as follows: 100 cases of goiter and follicular adenomas, 11 cases of follicular carcinoma, 35 cases of papillary carcinoma, 24 cases of oncocytic adenoma, 8 cases of oncocytic carcinoma and 20 cases of Hashimoto thyroiditis. About 30% of the cases from each class were used for training two LVQ classifiers. The remaining 139 cases, out of a total of 198, were used as the test set. A classifier was used to discriminate into four classes and a second into two classes. RESULTS: The application of LVQ neural networks allows good discrimination between benign and malignant lesions (O.A. = 97.8). However, reliable discrimination of the cytologic types of the lesions was not obtained. CONCLUSION: These results indicate that the use of neural networks combined with image morphometry may offer useful information on the potential for malignancy of thyroid lesions and may improve the diagnostic accuracy of FNA of the thyroid gland, especially in cases of follicular neoplasms classified as suspicious for malignancy and in cases of oncocytic tumors.     

Primary osteogenic sarcoma of the breast: cytomorphologic study of 3 cases with histologic correlation

BACKGROUND: Primary osteogenic sarcomas of the breast are extremely rare neoplasms. The histologic and cytologic features are comparable to those of their soft tissue and skeletal counterparts. To assess the utility of fine needle aspiration (FNA) in preoperative identification of osteogenic sarcomas, we retrospectively reviewed the FNA findings of 3 cases diagnosed in our hospital over 2 1/2 years. CASES: Three women, aged 48, 55 and 76 years, presented with a palpable lump of a few months' duration in their breasts. FNA was indicative of malignancy, and mastectomy with ipsilateral axillary lymph node dissection was performed. The cytologic features were of hypocellular or hypercellular smears with pleomorphic cells; scarce or abundant metachromatic amorphous material, suggestive of osteoid; osteoclast-like giant cells; and stromal fragments. CONCLUSION: Although cytologic features can be suggestive of osteosarcoma in the appropriate clinical setting, prompt preoperative diagnosis of malignancy in FNA samples of these tumors can avoid undertreatment, because mammographic and clinical findings are in many cases confused with the features of a benign lesion, more specifically calcified fibroadenoma.     

Fine needle aspiration cytology of primitive neuroectodermal tumors. A report of these cases.

Primitive neuroectodermal tumor (PNET) is a small round cell malignancy arising in soft tissue and bone, predominantly in older children and adolescents. We report the cytomorphologic features and findings of ancillary studies of eight fine needle aspiration (FNA) biopsies from three patients (7-year-old male, 12-year-old female, 9-year-old female). Two of the biopsies suggested the initial diagnosis of PNET of the chest wall, while the remaining six documented recurrent or metastatic disease. In one of these cases the primary diagnosis made by FNA biopsy enabled the pediatric oncologists to give specific therapy for the unresectable tumor and achieve remission. Local recurrences included the chest wall (two cases), pleura (one case) and pericardium (one case), while metastatic disease involved the supraclavicular lymph node and breast. All the cases consisted of small malignant cells with a high nuclear/cytoplasmic ratio and hyperchromatic nuclei without prominent nucleoli. Homer Wright rosettes were seen in only two of the aspirates, and neuropil and ganglion cells were not present. Ancillary studies, including electron microscopy (two cases), immunocytochemistry (four aspirates from two cases) and cytogenetics (11/22 translocation, one case) performed on the aspirated material were aids in making a specific diagnosis and excluded other small round cell tumors of childhood, such as malignant lymphoma, rhabdomyosarcoma and Ewing's sarcoma. The differential diagnosis between PNET and neuroblastoma can be difficult on the basis of an FNA biopsy alone, although light microscopic morphologic differences exist. Clinical features (e.g., age, primary site, metastatic patterns), catecholamine levels, electron microscopy and cytogenetics are necessary in establishing the correct diagnosis.     

Diagnostic pitfalls in the fine needle aspiration of thyroid nodules. A study of 555 cases in Chinese patients

The diagnostic value and limitations of fine needle aspiration (FNA) were determined by examining 555 palpable thyroid nodules in Chinese patients who had a definitive diagnosis established by thyroidectomy (529 cases) or large-needle biopsy (26 cases). Of the aspirates, 97.8% were satisfactory for cytologic examination. The overall malignancy rate was 20%. FNA detected 73 (74.5%) of 98 primary malignant tumors and 9 (90%) of 10 metastatic tumors. Diagnostic errors were most commonly due to inadequate specimens and cystic lesions. Cystic fluid, present in one-third of all lesions, was associated with a malignant nodule in 13% of the cases. FNA was most valuable for detecting papillary carcinomas; it may at times suggest the likelihood of a follicular carcinoma.     

Fine needle aspiration (FNA) of testicular germ cell tumours; a 10-year experience in a community hospital

garcía-solano j., sánchez-sánchez c., montalbán-romero s., sola-pérez j. and pérez-guillermo m. (1998) Cytopathology 9, 248–262
Fine needle aspiration (FNA) of testicular germ cell tumours; a 10-year experience in a community hospital
A retrospective reappraisal is made of the smears of 29 testicular germ cell tumours (TGCT) studied by FNA in which both orchiectomy specimens and histologic diagnoses were available. In 22 cases (75.86%) the yield was sufficient and contained cells suitable for cytologic diagnosis; in these 22 cases a diagnosis of malignancy was reached. In four cases (13.79%) the yield was sparse and diagnostic cells were partially obscured by haemorrhage and necrosis; these cases were categorized as suspicious of malignancy. In three cases (10.34%) the yield was not suitable for cytologic evaluation because haemorrhage and necrosis hampered evaluation of diagnostic cells. The cytologic findings that enable a reliable diagnosis of TGCT are described and those cytologic features that may lead the less experienced cytopathologist into an erroneous diagnosis are discussed. Pure TGCT can be confidently diagnosed with FNA and mixed TGCT can be successfully diagnosed, although it is difficult to recognize every cytologic subtype observed in the histologic sections. Despite the advantages of FNA for the prompt diagnosis of TGCT, FNA can not fully replace the histologic diagnosis and should rather be considered as a helpful tool in the work-up of testicular tumours.     

Myoepithelioma of the parotid gland initially diagnosed by fine needle aspiration cytology and immunocytochemistry: a case report

BACKGROUND: Myoepithelioma is a rare, benign tumor of the salivary gland, most commonly affecting the parotid gland. Although the cytologic features of myoepithelioma are documented in a few case reports, it has rarely been diagnosed preoperatively by fine needle aspiration (FNA) cytology. CASE: A 33-year-old man presented with a left parotid swelling 2.5 cm in diameter and of about 5 years' duration. FNA smears showed bundles of spindle-shaped cells as well as plasmacytoid and stellate cells in sheets and dissociated forms. A few cells had nuclear grooves, and occasional cells showed intranuclear cytoplasmic inclusions. In May-Grünwald-Giemsa-stained smears, most of the cells had reddish cytoplasm. Red to purple, myxoid matrix was present as a scanty fibrillar substance and as globules surrounded by tumor cells vaguely reminiscent of adenoid cystic carcinoma. A cytodiagnosis of myoepithelioma was given and corroborated by immunocytochemical staining, which revealed a positive reaction for vimentin, smooth muscle actin and S-100 protein. Epithelial membrane antigen yielded a negative reaction except for a few plasmacytoid cells with weakly positive staining. Histopathology of the resected tumor and immunohistochemical staining confirmed the cytodiagnosis of myoepithelioma. CONCLUSION: FNA cytologic features together with immunocytochemical studies on smears can offer a preoperative diagnosis of myoepithelioma.     

Features of benign granular cell tumor on fine needle aspiration.

OBJECTIVE: To describe the cytomorphologic features of benign granular cell tumor (GCT) on fine needle aspiration (FNA) biopsy and discuss the differential diagnosis. STUDY DESIGN: We reviewed three fine needle aspirates of surgically confirmed benign GCT. Immunocytochemical staining for S-100 was performed on the aspirate smear in one case. RESULTS: Two GCT were thigh lesions, where lipoma and fibromatosis were the leading clinical diagnosis, and the third was a breast mass clinically suspected to be a fibroadenoma. All FNA specimens were highly cellular and composed of fairly uniform cells with eccentric, round-to-slightly oval nuclei and abundant, finely granular cytoplasm. The cells were fragile, with stripped nuclei in a background of finely granular material. Occasional cells with nuclear pleomorphism and small-but-conspicuous nucleoli were identified. There was no evidence of necrosis or mitotic activity. Rare intranuclear cytoplasmic inclusions were identified in two cases. The granular cells were immunoreactive for S-100 in the case studied. CONCLUSION: Benign GCT has a distinctive cytomorphologic appearance that permits its diagnosis on FNA. High cellularity, occasional cells with nuclear pleomorphism and prominent nucleoli are features that can be present in benign GCT. Mitotic figures and necrosis should be identified before a diagnosis of malignancy is rendered.