Grading of spindle cell sarcomas in fine-needle aspiration biopsy specimens

We studied whether histologic criteria for grading sarcomas could be applied to fine-needle aspiration biopsy (FNAB) specimens of adult spindle cell sarcomas, without knowledge of the sarcoma subtype, by reviewing 36 specimens. Grade 1 was assigned for minimal nuclear atypia and overlap, no necrosis, and rare mitotic figures, and grade 2 for moderate nuclear atypia, at least moderate nuclear overlap, appreciable mitotic figures, and necrosis. Severe nuclear atypia distinguished grade 3 from grade 2. A major noncorrelation between FNAB and histologic grades was defined as a misclassification of grade 1 vs grade 2 or 3. FNAB grades assigned were grade 1, 1; grade 2, 25; and grade 3, 10. There was 1 major noncorrelation due to a probable FNAB interpretation error. In 15 of 16 FNAB specimens of grade 2 or 3 sarcomas lacking mitotic figures, necrosis, or both, the nuclear atypia reflected the grade. In the remaining case, the degree of nuclear overlap and necrosis determined the grade. The histologic grading of sarcomas can be applied accurately to most FNAB specimens of spindle cell sarcomas without knowledge of the sarcoma subtype.     

Electron microscopy of fine-needle aspiration biopsy specimens: a brief review.

The cellular sample obtained by fine-needle aspiration biopsy is usually small and therefore requires extreme care during processing for electron microscopy. The most significant technical problem is due to contamination of the sample by red blood cells, which tend to dilute the samples. Red blood cells in these samples may be removed prior to processing by either using Bovine serum albumin as a gradient or by filtration of the specimen by a nylon sieve. Experience at our institution with the use of electron microscopy for interpretation of fine-needle aspiration biopsy samples is briefly reviewed.     

Pediatric fine-needle aspiration biopsy.

A total of 135 fine-needle aspiration (FNA) biopsies from varying sites were performed in 123 children (mean, 10.5 years; range, one day to 18 years) over a five-year period. One hundred thirty (96.3%) biopsy specimens were satisfactory for evaluation. Seventy-nine cases were nonneoplastic (60.8%); among these cases, a specific diagnosis of infectious disease was made in 17 (13.1%). A diagnosis of neoplastic disease was made in 50 (38.5%) cases, of which 14 (10.8%) were benign, 28 (21.5%) were malignant, and 8 (6.2%) were neoplasms of uncertain biologic potential. The sensitivity of pediatric FNA biopsies was 90.6%, specificity 100%, positive predictive value 100%, negative predictive value 94.7%, and efficiency of the test 96.5%. There were no false-positive diagnoses and there were four false-negative diagnoses, three of which involved aspirates of the central nervous system (CNS). Ancillary studies, including immunocytochemistry (20 cases), electron microscopic examination (18 cases), microbiologic culture (8 cases), cytogenetic studies (7 cases), and flow cytometry (3 cases), were performed on the aspirated material, enabling a more specific diagnosis or supplying additional information in many cases. Definitive diagnosis by FNA biopsy enabled radiation therapy and/or chemotherapy to be administered for unresectable malignant neoplasms, provided material for culture of infectious lesions, identified benign lesions not needing surgery, and aided the surgeon in planning the extent of surgery in resectable malignant neoplasms. These results support the greater use of FNA biopsy in the pediatric population.     

Immunofluorescence microscopy of paraffin-embedded human kidney specimens obtained by fine-needle aspiration biopsy

Recently, we have introduced an atraumatic fine-needle aspiration biopsy method to obtain human glomeruli for morphologic investigation. In the present study, immunofluorescence microscopy of paraffin-embedded, fine-needle specimens is described. The specimens were obtained by aspiration with a 10-mL syringe fitted to the fine-needle prepared from a lumbar puncture needle (Jintan Terumo). Embedding of the specimens into conventional paraffin blocks was carried out after pelleting them by centrifugation between processing steps in conical centrifuge tubes. Sections from the blocks were collected on small pieces of GelBond film (FMC Corporation) instead of objective slides, which prevented the detachment of small sections during enzyme treatment. Localization then was performed on deparaffinized trypsin-digested sections using fluorescein-labeled antibodies. The choice of fixative and digestive enzymes was found to have a marked effect on the localization; periodate-lysine-paraformaldehyde fixative and trypsin digestion gave the most reliable results.     

Solitary pleural amyloid nodules occurring as coin lesions diagnosed by fine-needle aspiration biopsy

Solitary pleural amyloid nodule is rare and radiologically can mimic neoplastic lesions. This report describes two cases of this entity diagnosed by fine-needle aspiration biopsy in patients without systemic amyloid deposits. The histologic, ultrastructural, and cytologic features are described.     

Quality assurance in a fine-needle aspiration biopsy service.

Fine-needle aspiration biopsy (FNAB) is an increasingly popular tool for the evaluation of a variety of palpable and nonpalpable masses. Its acceptance has been based on its simplicity, safety, and accuracy. It is its accuracy that is crucial and that requires careful clinical and/or histologic follow-up. In order to satisfy our own department's quality assurance requirements, we developed a computer-based searching program that effectively identifies FNAB cases in which there was histologic follow-up and retrieves the necessary information to produce a meaningful quality assurance report.     

Megakaryocytes in fine-needle aspiration biopsy of breast

An unusual case in which megakaryocytes were found in fine needle aspirate of a breast lesion is reported. The megakaryocytes in the smears were initially mistaken to be malignant cells. However, the cell block sections available later showed normal bone marrow particles, indicating that an inadvertent puncture of a rib was the reason for the presence of megakaryocytes in the smears.     

Immunocytochemical study of the expression of mesothelin in fine-needle aspiration biopsy specimens of pancreatic adenocarcinoma

Mesothelin is a potential marker of pancreatic adenocarcinoma that was recently identified by serial analysis of gene expression. We evaluated the sensitivity and specificity of mesothelin as a marker of pancreatic adenocarcinoma on destained Papanicolaou (Pap) smears and unstained cellblocks from 28 patients using a monoclonal antibody to mesothelin. Intensity and proportion of staining was semiquantitatively graded on a scale of 1-3, and as 0%, 1 to <10%, 10-50%, or >50%. Positive staining for mesothelin was seen in 64% of the direct smears and in 36% of cell block sections. Focal positivity for mesothelin was noted in benign pancreatic tissue in one of 10 cases. Staining was most often focal (<50% of cells) in both direct smears and cell block sections. The overall sensitivity and specificity of mesothelin as a marker for pancreatic adenocarcinoma were 68% and 90%, respectively. Sensitivity was higher in Pap smears than in cell block sections (64% versus 36%). The presence of occasional mesothelin expression in benign tissue, its very focal expression in malignant tissue may limit the utility of mesothelin as a marker of pancreatic adenocarcinomas in fine-needle aspiration (FNA) specimens.     

Intraocular fine-needle aspiration biopsy of coronal adenomas

The cytologic findings from intraocular biopsy of coronal adenomas of three previously surgically enucleated eyes were studied. Cohesive clusters of nonpigmented epithelial cells were observed. Clusters of epithelial cells were surrounded by characteristic intercellular matrix material. Coronal adenomas have been clinically mistaken for intraocular melanomas. It is important for pathologists to be familiar with the aspiration cytology of the coronal adenoma to avoid unnecessary enucleation or iridocyclectomy.     

Usefulness of S100P in diagnosis of adenocarcinoma of pancreas on fine-needle aspiration biopsy specimens

Even though the cytologic criteria for pancreatic ductal adenocarcinoma (PDA) on fine-needle aspiration biopsy (FNAB) specimens have been well defined, a diagnostic challenge is still present. We immunohistochemically evaluated the diagnostic value of S100P on cell-block and/or smear preparations in 58 cases of FNAB specimens of the pancreas. The 58 cases were divided into 4 groups: 1, 32 cases of PDA; 2, 6 cases with an atypical or "suspicious" diagnosis; 3, 14 cases of benign or reactive ductal epithelium; and 4, 6 cases of endocrine tumor. Positive immunoreactivity for S100P was observed in all cases in groups 1 and 2, whereas only 1 of 14 cases in group 3 was positive for S100P. All cases in group 4 were negative for S100P. S100P is a sensitive and specific marker for the detection of PDA on FNAB specimens on cell-block and smear preparations.     

Percutaneous fine-needle aspiration biopsy of the pancreas

Percutaneous fine needle aspiration biopsy of the pancreas allows to obtain without surgery a tissue proven diagnosis of focal lesions of the pancreas. Ultrasound (US), computed tomography (CT), or fluoroscopy are used to guide the positioning of the needle in the lesion. Various benign and malignant lesions can be diagnosed and the cytologic features of them are presented. The average sensitivity of the technique in the diagnosis of pancreatic carcinoma is 80.5% in the literature. The use of percutaneous fine needle biopsy of the pancreas decreases the number of investigations to be done in a patient with pancreatic disease.     

Angiomatoid malignant fibrous histiocytoma. Cytology of fine-needle aspiration and its differential diagnosis

A case of angiomatoid malignant fibrous histiocytoma was studied by fine-needle aspiration biopsy and routine histologic methods. Smears from aspirated material consisted of numerous large loose cellular aggregates with occasional single cells. Histiocytelike cells and lymphocytes were the prominent cell types with lesser numbers of spindle-shaped, fibroblastlike cells. Moderate cytologic atypia was noted. A cystic mass with the above cytologic findings occurring in the superficial soft tissue of the extremity of a young patient should suggest the diagnosis of an angiomatoid malignant fibrous histiocytoma.     

PAX-5 expression in pulmonary neuroendocrine neoplasms: its usefulness in surgical and fine-needle aspiration biopsy specimens

The World Health Organization classification of lung tumors recognizes 4 histologic subtypes of pulmonary neuroendocrine carcinomas (NECs), which include typical carcinoids (TCs), atypical carcinoids (ACs), small cell carcinomas (SCCs), and large cell NECs (LCNECs). These tumors can be misclassified owing to morphologic parallels, indicating the necessity for adjunctive tests for correct classification. We evaluated immunohistochemical expression of PAX-5 in histologic and fine-needle aspiration (FNA) specimens of pulmonary NECs. Staining was stratified by intensity (0 to 3+) and percentage of cells stained as focal (<10%) or diffuse (=10%). PAX-5 expression was present in 29/37 (78%) of high-grade NECs (22/26 SCCs, 1/2 LCNECs, and 6/9 combined tumors) and none of 51 TCs and ACs; FNA specimens showed concordant staining. This study confirmed that PAX-5 is a useful marker in FNA and surgical specimens for the discrimination of low- to intermediate-grade NECs from high-grade NECs with 100% specificity and 79% sensitivity in surgical specimens.     

Value of ancillary studies in fine-needle aspiration biopsy

With growing interest in the application of fine-needle aspiration biopsy (FNAB) in primary diagnosis of benign and malignant lesions, there has been a significant increase in the use of ancillary studies in the aspirated material. To assess the value of such studies, we reviewed 254 morphologically difficult aspiration biopsy cases obtained from different sites that underwent ancillary studies which included microbiology (MC), special stains (SS), immunocytochemistry (ICC), electron microscopy (EM) and flow cytometry (FC). Correlation with available histologic material and/or pertinent clinical information was used as a “gold” standard. In some cases, more than one ancillary study was performed on a single aspirate. According to the impact of the ancillary studies on the final diagnosis, these studies were divided into three categories: confirmatory/ diagnostic (22%), helpful (41%), and non-helpful (37%). Overall, more studies had positive contributory effect to the diagnosis (63%) than those with non-helpful results (37%). Among these adjunct testings, ICC were the most commonly used tests (135/296, 46%), while the EM studies had more positive impact in establishing the diagnosis. These findings emphasize the usefulness of ancillary testings in FNAB and justify the more selective use of these studies in the aspirated material. © 1995 Wiley-Liss, Inc.