Breast solitary schwannoma: Fine-needle aspiration biopsy and immunocytochemical analysis

A case of intramammary solitary schwannoma (SS) (benign neurilemoma) diagnosed by fine-needle aspiration biopsy (FNAB) and supported by immunocytochemical study is reported. The tumor arose in the right breast of an 18-yr-old woman and was clinically and radiologically considered a fibroadenoma. The smears obtained by FNAB of the lump showed clusters of spindle-shaped cells and suggested a benign mesenchymal neoplasm. The presence of some structures reminiscent of Verocay bodies and the immunocytochemical reactivity for S-100 protein antiserum demonstrated the schwannian nature of the tumor and suggested the diagnosis of SS. The final histologic examination confirmed the cytologic diagnosis. © 1994 Wiley-Liss, Inc.     

Fibroadenomas with atypia: causes of under- and overdiagnosis by aspiration biopsy.

Fibroadenoma (FA) is a common benign breast lesion frequently sampled by fine-needle aspiration biopsy (FNAB). Although the cytologic diagnosis is straightforward in most cases, cellular discohesion and atypia in FAs may lead to falsely atypical or positive FNAB diagnoses. Conversely, some adenocarcinomas mimic a fibroadenomatous pattern on FNAB, resulting in a false-negative diagnosis. We reviewed the cytologic and histologic findings in 25 cases with a preoperative FNAB diagnosis of FA, wherein excision was recommended based on atypia. Our aim was to analyze the spectrum of changes causing under- or overdiagnosis in such cases. The smears were assessed for cellularity, cellular discohesion, presence of dissociated intact cells and nucleoli, nuclear pleomorphism, oval bare nuclei, and stromal fragments. The histologic findings were correlated with FNAB features. At excision, 88% of FAs classified as atypical on FNAB were benign (FA with ductal hyperplasia and lactational change, myxoid FA, and other fibroepithelial lesions). Differentiating myxoid FA from colloid carcinoma was difficult due to the abundance of extracellular mucin in which the dissociated epithelial cells were floating. Two (8%) cases were carcinomas on excision; the reasons for underdiagnosis in one case reflected sampling, and in the other, interpretative error. There was one (4%) benign phyllodes tumor which lacked stromal fragments and single stromal cells on FNAB smears. The lesion was called atypical, based on the epithelial discohesion on the smears. We conclude that the majority of FAs with atypia on FNAB are benign lesions. Considering the grave consequences of a false-positive cytologic diagnosis, we recommend a conservative approach in interpreting FNAB smears which overall display a fibroadenomatous pattern.     

Fine-needle aspiration biopsy of angio-immunoblastic lymphadenopathy

In this article, we have described the fine-needle aspiration biopsy (FNAB) of five cases of angioimmunoblastic lymphadenopathy (AILD). FNAB of these cases showed large number of capillary fragments, along with polymorphous population of cells consisting of plenty of immunoblasts, plasma cells, eosinophils, and mast cells. Two cases showed clusters of clear cells. It is essential to have detailed clinical features for FNAB diagnosis of AILD. Histopathology is advisable in all the fresh cases. FNAB is helpful for screening and follow-up of AILD. Diagn Cytopathol 1996;15:412–414. © 1996 Wiley-Liss, Inc.     

Neutrophil-rich Ki-1-positive anaplastic large cell lymphoma: a study by fine-needle aspiration biopsy

Fine-needle aspiration biopsy (FNAB) is an accurate, cost-effective method of evaluating lymphomas. The neutrophil-rich variant of anaplastic large cell lymphoma (NR-ALCL) is a rare non-Hodgkin lymphoma. To our knowledge, we present thefirst study of NR-ALCL by FNAB cytology. Histologic confirmation was available for both patients. Both cases were positive for Ki-1 (CD-30) and were either T-cell or null-cell phenotype. FNAB specimens were highly cellular with a single-cell pattern composed of pleomorphic tumor cells, "hallmark" tumor cells, and a background rich in neutrophils that occasionally obscured tumor cells. Diagnosis on FNAB is difficult owing to the rarity of this tumor, its resemblance to Hodgkin lymphoma and other non-Hodgkin lymphomas that express CD30, its similarity to an infectious process, and its occasional confusion with metastatic carcinoma and melanoma. Reproducible cytologic features usually are present, and the diagnosis can be made conclusively by FNAB in conjunction with ancillary studies.     

Tissue Harvester with Functional Valve (THFV): Shidham's device for reproducibly higher specimen yield by fine needle aspiration biopsy with easy to perform steps

Background  

Fine needle aspiration biopsy (FNAB) cytology has been a highly effective methodology for tissue diagnosis and for various ancillary studies including molecular tests. In addition to other benefits, FNAB predominantly retrieves the diagnostic loosely cohesive cells in the lesion as compared to the adjacent supporting stroma with relatively higher cohesiveness. However, FNAB procedure performed with currently available resources is highly skill dependent with inter-performer variability, which compromises its full potential as a diagnostic tool. In this study we report a device overcoming these limitations.     

Fine‐needle aspiration biopsy of endometriosis of the abdominal wall: A potential diagnostic pitfall

Endometriosis is a relatively common disease in women, usually of reproductive age. In rare occasions, endometriosis may occur in unusual body sites, including extragonadal, extra‐pelvic sites, or in the skin. We report a case of endometriosis of the abdominal wall diagnosed by fine‐needle aspiration biopsy (FNAB). The patient was a 41‐year‐old woman with a clinical impression of “desmoid” tumor of the abdominal wall. FNAB showed groups of epithelial cells with mild nuclear atypia and rare mitoses. A few small clusters of slightly atypical spindle cells were also seen. The initial screening impression was adenocarcinoma due to the atypical cytological features. However, after review with the pathologist, the FNAB was signed out as “endometriosis.” Subsequent local excisional biopsy confirmed the diagnosis of endometriosis. In conclusion, endometriosis may present diagnostic challenges in FNAB and this possibility should be considered in differential diagnosis. A clinical cytopathological correlation is necessary to avoid a misdiagnosed as an adenocarcinoma. Diagn. Cytopathol. 2011. © 2010 Wiley‐Liss, 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.     

Suture granuloma mimicking recurrent thyroid carcinoma on ultrasonography

Although high resolution ultrasonography (US) is helpful in the differentiation of suture granulomas from recurrent thyroid cancer in most cases, a definite diagnosis cannot always be made. We report a case that mimicked recurrent thyroid cancer on US and 2-[fluorine-18] fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), but diagnosis of a suture granuloma was confirmed by a US-guided fine needle aspiration biopsy (FNAB). In order to avoid unnecessary operations, the differential diagnosis between postoperative suture granulomas and recurrent cancer is important.     

Fine-needle aspiration biopsy of cystic pleomorphic adenoma with adnexa-like differentiation mimicking mucoepidermoid carcinoma: a case report

Although pleomorphic adenomas (PAs) usually can be diagnosed very accurately with fine-needle aspiration biopsy (FNAB), even this common salivary gland neoplasm can be diagnostically challenging and cause pitfalls in cytodiagnosis. In particular, the presence of either cystic changes or squamous, mucinous, or sebaceous metaplasia can lead to a false positive diagnosis of mucoepidermoid carcinoma (MEC). Here, we present a case of a 70-yr-old man with an asymptomatic left deep lobe parotid mass for which CT-guided FNAB was performed. The FNAB cytology revealed cohesive clusters of squamous epithelial cells, sebaceous cells, oncocytes, macrophages, and rare myoepithelial cells. Characteristic metachromatic fibrillar chondromyxoid stroma, which usually is seen in PAs, was not seen in the aspirate. Although cytodiagnosis of PAs was suggested based on the presence of other cellular components, resection was recommended. The subsequent parotidectomy specimen revealed an encapsulated cystic PA with mixed appendageal differentiation including areas of squamous, mucinous, sebaceous, and oncocytic metaplasia. Chondromyxoid stroma was only focally present. Presence of squamous, mucinous, and/or sebaceous metaplasia, especially in the absence of chondromyxoid stroma, presents the potential for misinterpretation of the FNAB as indicative of malignancy in general and MEC in particular.     

Fine-needle aspiration biopsy of solid aneurysmal bone cyst in the humerus

We report the fine-needle aspiration biopsy (FNAB) cytology findings of a solid aneurysmal bone cyst in the left humerus of a 69-yr-old woman. Radiographically, the lesion showed an extensive, relatively well-defined osteolysis in the diaphysis, with a pathologic fracture. FNAB smears of the lesion consisted of benign, mononuclear cells and numerous osteoclast-like multinucleated giant cells. Some clusters of the mononuclear cells were closely associated with dense, homogeneous, extracellular, matrix material. To our knowledge, the FNAB features of solid ABC of the long bones have not been described previously in the English-language literature. The cytologic features are indistinguishable from those of giant cell tumors of bone and brown tumors of hyperparathyroidism.     

Hodgkin's disease mimicking suppurative lymphadenitis: a possible pitfall in fine-needle aspiration biopsy cytology

We report one case of nodular sclerosing Hodgkin's disease with uncommon pseudosuppurative presentations in fine-needle aspiration biopsy (FNAB) samples and on histopathologic material. The criteria for cytologic diagnosis include atypical mononuclear cells and diagnostic SR cells in the purulent exudate. This lesion is considered a possible pitfall in FNAB cytology of Hodgkin's disease.     

Aneurysmal bone cyst: fine-needle aspiration findings in 23 patients with clinical and radiologic correlation

Aneurysmal bone cyst (ABC) is an osseous mass lesion that accounts for 1% of primary bone tumors. We describe 23 cases of ABC initially evaluated by fine-needle aspiration biopsy (FNAB). In 4 cases, the ABC was secondary to another primary tumor. Aspirates from 6 cases (26%) were insufficient. Twelve aspirates diagnosed as ABC by FNAB were confirmed as ABC by histologic examination. The accuracy of FNAB was 82% when cases insufficient for evaluation were excluded. One case diagnosed as ABC cytologically was subsequently found to be metastatic carcinoma. In another, the specimen was interpreted as ABC vs giant cell tumor. In the remainder, a diagnosis of ABC was favored cytologically. Owing to the nonspecific findings, ABC cannot be definitively diagnosed by FNAB. However, the presence of typical clinical and radiographic features in conjunction with a blood-rich, mesenchymal cell containing aspirate devoid of overtly malignant cells strongly suggests the diagnosis of ABC.     

Mixed hepatoblastoma diagnosed by fine-needle aspiration biopsy cytology: A case report

The cytologic features of a case of mixed hepatoblastoma diagnosed by fine-needle aspiration biopsy (FNAB) in a 2½-yr-old child are described. FNAB was carried out on a large, firm mass in the upper abdomen, without any complications. The characteristic cytologic features were clusters of polyhedral cells with mild anisonucleosis, and intracytoplasmic bile pigment. Focal areas of mesenchymal elements were seen. Immature hematopoietic cells were present. FNAB offers a safe and accurate method of diagnosis. Diagn. Cytopathol. 1998;19:306–308. © 1998 Wiley-Liss, Inc.     

Diagnostic accuracy of image-guided percutaneous fine needle aspiration biopsy of the mediastinum

Interpreting a fine needle aspiration biopsy (FNAB) from the mediastinum is challenging as this location may harbor many lesions, including primary and metastatic tumors. Image-guided transthoracic (percutaneous) FNAB is less invasive than mediastinoscopy or endoscopic-guided FNAB. The aim of this study was to determine the diagnostic accuracy of FNAB performed percutaneously for evaluating mediastinal lesions.A retrospective study of 157 consecutive CT-guided transthoracic FNAB of the mediastinum was performed (1988-2004). Direct smears (N = 145; average 13 slides/case), ThinPrep slides (N = 25), and adequate cell blocks (N = 131) were prepared from procured cytologic material. When needed, ancillary studies included immunocytochemistry (N = 53) and flow cytometry (N = 8). Subsequent histologic tissue diagnoses available for 68 cases were also reviewed.Patients were of average age 57 yr (range 1-88 yr), including 75 males and 82 females. A definitive diagnosis was rendered in 128 (82%) cases. Primary neoplasms (N = 38) included 24 lymphomas (6 Hodgkin and 18 non-Hodgkin), 7 thymomas, 1 thymic carcinoma, and 6 peripheral nerve sheath tumors. Metastases (N = 72) were mainly carcinomas (N = 71) and 1 melanoma. There were 4 non-neoplastic lesions (1 granulomatous process; 2 bronchogenic and 1 pericardial cyst), 1 case of undifferentiated malignant large cell neoplasm, 13 cases negative for malignancy, and 29 (18%) that were indeterminate, due largely to insufficient cellularity. Subsequent histologic diagnoses were concordant with FNAB diagnoses in 53/68 cases (78%). Nine FNAB were inadequate/nondiagnostic. There were 6 discordant cases, including 5 FNAB that were of adequate cellularity but interpreted as negative for malignant cells (on subsequent histology 2 turned out to be Hodgkin lymphoma, 2 carcinomas, and 1 diffuse large cell lymphoma), and 1 diagnosed as thymoma that on histologic evaluation was a thymic large cell lymphoma.Adequate diagnostic cytologic material was obtained by image-guided percutaneous FNAB of mediastinal lesions in 82% of our cases. Sufficient material was available to make cell blocks and perform ancillary studies when necessary. These data also show a high proportion of agreement (78%) between FNAB and subsequent histologic diagnoses for a wide variety of mediastinal lesions. The majority of discordant cases were primarily interpretive, with a final cytologic diagnosis negative for malignancy. Only one problematic case misdiagnosed on FNAB as thymoma was found on subsequent surgical excision to be a thymic large B cell lymphoma. Cases with nondefinitive FNAB diagnoses were largely due to sampling error and/or insufficient cellularity. Therefore, percutaneous FNAB of the mediastinum is a diagnostically helpful, minimally invasive procedure that can be performed in patients of all ages as part of the evaluation of a mediastinal mass lesion.     

Cytologic features of metastatic sebaceous carcinoma: report of two cases with comparison to three cases of basal cell carcinoma.

The cytologic findings of two cases of metastatic sebaceous carcinoma are described and compared to three cases of locally recurrent basal cell carcinoma. Morphological findings for sebaceous carcinoma in fine-needle aspiration biopsy (FNAB) smears included cellular, loosely cohesive cell clusters with central necrosis, squamous pearl formation, and adjacent keratin debris. The tumor cells had moderate amounts of vacuolated cytoplasm, round to oval vesicular nuclei with clumped chromatin, nucleoli, some nuclear overlap, and numerous mitotic figures. An interesting finding was the presence of numerous multinucleated giant cells, probably responding to extravasated lipid or keratin material. In contrast, the FNAB smears of basal cell carcinoma typically were less cellular, with more tightly cohesive and smaller clusters of uniform hyperchromatic basaloid cells with high nuclear to cytoplasmic ratios, and a narrow rim of cytoplasm without vacuolization. The morphologic features of sebaceous carcinoma in FNAB smears appear to be distinct from those of basal cell carcinoma. FNAB can be a useful preoperative diagnostic technique to distinguish these two cutaneous malignancies.     

Fine-needle aspiration biopsy of a cystic pleomorphic adenoma with extensive adnexa-like differentiation: differential diagnostic pitfall with mucoepidermoid carcinoma

Although fine-needle aspiration biopsy (FNAB) is a highly accurate tool for the diagnosis of pleomorphic adenomas, even this common salivary gland neoplasm can be diagnostically challenging and cause pitfalls in cytodiagnosis. In particular, the presence of either cystic degeneration or squamous and mucinous metaplasia can lead to a false positive diagnosis of malignancy. Here we present the case of a 16-year-old female who presented with a painless, slowly growing mass in the superficial lobe of the right parotid gland. Magnetic resonance imaging of the parotid demonstrated a mass with heterogeneous postcontrast enhancement and a central, nonenhancing area suggestive of necrosis. FNAB of the lesion yielded proteinaceous debris and numerous whorls of keratin, small cohesive clusters of basaloid and squamoid epithelial cells, and many vacuolated and foamy cells. Initially and after consultation at an outside institution, the FNAB was reported as an "atypical neoplasm, cannot exclude mucoepidermoid carcinoma." A total, nerve-sparing parotidectomy and level II neck dissection revealed a pleomorphic adenoma with central cystic degeneration and extensive mixed appendageal differentiation. While foci of squamous metaplastic changes may occur in pleomorphic adenomas, the combination of cystic degeneration and extensive appendageal differentiation with numerous keratotic cysts is rare, and it presents the potential for misinterpretation of the FNAB as indicative of malignancy in general, and mucoepidermoid carcinoma in particular.     

Histiocytic aggregates in benign nodular goiters mimicking cytologic features of papillary thyroid carcinoma (PTC)

Macrophages/histiocytes are commonly seen in fine-needle aspiration biopsy (FNAB) specimens of thyroid nodules with varying degrees of cystic change. In some cases the histiocytic component of a cystic thyroid nodule can occur as large tissue fragments with marked nuclear atypia, including elongated nuclei with chromatin clearing, nuclear grooves, and membrane thickening. These nuclear changes mimic cytologic features of papillary thyroid carcinoma (PTC), thus leading to diagnostic difficulty in interpretation of FNAB specimens of benign cystic thyroid nodules. We evaluated ethanol-fixed Papanicolaou-stained smears of 273 cases of FNAB thyroid specimens from goitrous nodules with cystic change. Twenty cases were selected due to the presence of large aggregates of histiocytic cells with the above-mentioned nuclear atypia. An immunostain for histiocytic cells using CD68 was performed on alcohol-fixed slides. Histiocytic cells in tissue fragments with nuclear atypia mimicking PTC nuclei showed strong cytoplasmic staining for CD68; thyroid follicular cells stained negative for CD68. We conclude that histiocytic cells in cystic goitrous nodules can show nuclear features, which appear similar to PTC nuclei. Immunostaining for CD68 may be of value in differentiating between benign cystic thyroid nodules with histiocytic aggregates that mimic cytologic features of papillary carcinoma, and PTC with cystic change.     

Spectrum of morphologic changes in lymph nodes attributable to fine needle aspiration.

Fine needle aspiration biopsy (FNAB) is a commonly used diagnostic tool for the investigation of lymphadenopathy, but little has been written about the morphologic changes resulting from this procedure and whether these changes interfere with subsequent histologic assessment. We therefore reviewed the histologic sections of a consecutive series of lymph node biopsies with previous FNAB. Ten out of 230 such cases showed changes attributable to FNAB. In four cases, hemorrhage accompanied by various stages of organization was seen, with a linear needle tract being identified in two of them. Proliferation of spindle cells around the hemorrhagic foci could raise a concern for Kaposi's sarcoma. Three cases showed segmental infarction of the nodal parenchyma, characterized by a wedge-shaped area of lymphocyte depletion and hemorrhage. Three cases showed total coagulative necrosis, which was attributable to the effects of FNAB rather than to spontaneous occurrence because the aspirates yielded abundant viable large atypical lymphoid cells. These three cases of total infarction were proven to be large-cell lymphoma upon subsequent biopsies. We conclude that the FNAB procedure may rarely affect histologic assessment of lymph nodes when there is florid myofibroblastic proliferation or total infarction. The latter complication is more likely to occur in lymph nodes involved by malignant lymphoma.     

Cytopathology of malignant mesothelioma of the pleura in fine-needle aspiration biopsy

The cytologic findings in fine-needle aspiration biopsy (FNAB) of 9 histologically, immunohistochemically, and ultrastructurally confirmed malignant mesotheliomas of the pleura were reviewed. There were 4 epithelial malignant mesotheliomas (EMM), 3 sarcomatous mesotheliomas (SM), 1 mixed malignant mesothelioma (MMM), and 1 poorly differentiated malignant mesothelioma (PDMM). In FNAB, three EMMs yielded polygonal malignant cells with oval nuclei and prominent nucleoli, singly, in small sheets, and in tridimensional clusters with smooth or lobulated contours. In one EMM, only atypical mesothelial cells with prominent nucleoli were seen singly and in loose aggregates. In FNAB, two SM showed malignant spindle-shaped cells (MSC) with scant, ill-defined cytoplasm singly and in loose clusters. Cohesive clusters of elongated and polygonal cells with ill-defined, clear cytoplasm and pleomorphic nuclei containing small or prominent nucleoli were observed in one SM, with extensive clear-cell changes. In needle aspirates, the MMM showed polygonal malignant cells in clusters admixed with MSC. The PDMM displayed single and clustered large pleomorphic malignant cells, with prominent single or multiple nucleoli. Electron microscopic examination of minute tissue fragments retrieved from the FNAB in 2 cases of EMM revealed epithelial mesothelial cells with well-formed desmosomes and long slender microvilli (LSM) on the free tumor cell surfaces. In one case, LSM in direct contact with collagen fiber bundles in the tumor tissue matrix were observed, supporting the diagnosis of an invasive EMM. Diagn. Cytopathol. 1999;21:253-259.