Value of the cytologic analysis of fine needle aspiration biopsy specimens in the diagnosis of pancreatic carcinomas

Between 1982 and 1986, 410 preoperative percutaneous fine needle aspiration (FNA) biopsies of the pancreas were performed on 316 patients clinically suspected of having a malignant pancreatic tumor. Of 58 patients with pancreatic carcinomas subsequently confirmed by histologic investigation, the FNA biopsy yielded a cytologically positive diagnosis of carcinoma in 39 cases (67.2%) and suspicious findings in another 5 cases (8.6%). In 14 cases of malignancy (24.1%), the FNA puncture failed to sample material from the tumor; hence, the cytologic evaluation yielded false-negative results. Of 21 patients with inflammatory disorders of the pancreas, cytologically suspicious cells were observed in 5 cases (23.8%); in none of those 5 cases did the histologic examination show any evidence of carcinoma. This indicates that caution should be taken not to cytologically over-diagnose cases of pancreatitis. On the whole, cytology proved to be a valuable method for the diagnosis of pancreatic carcinoma; it provided the highest rate of positive results in comparison with other modern clinical diagnostic methods. Furthermore, cytology may improve the diagnostic results even in those cases with clinically negative or merely suspicious findings. FNA punctures of the pancreas produced no serious complications in this series.     

Comparison of cytologic and acridine-orange flow-cytometric detection of malignant cells in human body cavity fluids

Flow cytometrically (FCM) derived DNA and RNA profiles were studied in acridine orange (AO)-stained body cavity fluid (BCF) specimens obtained from 78 patients with various solid tissue and hematologic malignancies. The ploidy (DNA index), RNA content (RNA index), proliferative activity (% S + G2M) and DNA and RNA scattergram patterns were tested "double-blind" against the cytologic scoring of specimens as malignant, benign or reactive. It was determined that expression of an "abnormal" RNA index (greater than or equal to 2.8) and an elevated proliferative activity (% S + G2M greater than or equal to 7.4) was dependent on the presence of malignancy; 21 of 22 specimens having those abnormal indices had DNA aneuploidy and were cytologically scored as positive. The AO FCM sensitivity and specificity for detecting malignant cells (when measured against cytology scoring) were 61% and 90%, respectively, using the "abnormal" RNA index and % S + G2M cut-offs together with the cellular DNA aneuploidy marker. By supplementing the cytologic scoring with AO FCM DNA and RNA features, the sensitivity for detecting malignant cells was 94%, as compared to 72% for cytology alone. Two specimens gave false-positive FCM results: a tuberculous effusion with a tetraploid subpopulation and a reactive mesothelial proliferation that was diploid and negative cytologically. Scoring for malignancy based on the visual pattern of the DNA and RNA FCM scattergrams, while showing good correlation for aneuploid specimens, in some cases failed to identify diploid disease. The results demonstrate the usefulness of FCM DNA and RNA analysis for supplementing cytologic examination of BCF specimens for the purpose of detecting malignant cells.(ABSTRACT TRUNCATED AT 250 WORDS)     

Methodologic aspects of evaluating brush samples from biliary strictures by cytology and DNA flow cytometry

OBJECTIVE: To present a method of increasing the cell yield from brush samples of the biliary tree for measurement of DNA content by flow cytometry (FCM). STUDY DESIGN: One hundred eight cell specimens from 86 patients were studied by FCM for DNA ploidy and cell cycle composition. All specimens were cytologically classified into benign, suspicious for malignancy and malignant. Two methods for preparation of the cell material were compared. RESULTS: Enzymatic treatment of formalin-fixed brushes for release of cell nuclei was superior to mechanical removal of the cells. The fraction of samples not possible to assess was reduced from 27% to 4%, and good quality histograms increased from 21% to 62%. Aneuploidy was detected in 7% of benign and 57% of suspicious malignant samples. Using DNA analysis in addition to cytology as a diagnostic marker for cancer, the sensitivity increased from 12% to 31%. CONCLUSION: FCM of cells from biliary strictures can be used routinely as an adjunct to cytology for DNA analysis.     

Flow cytometric analysis and cytopathology of body cavity fluids

A total of 75 samples of body cavity fluids from 71 patients were analyzed by both flow cytometry (FCM), to detect cells with an abnormal DNA content (aneuploidy), and by conventional cytopathology. Samples included 27 pleural fluids, 35 peritoneal fluids, 11 peritoneal washings and 2 pericardial fluids. For cytologic examination, the samples were prepared using standard techniques. Samples for FCM analysis were centrifuged and exposed to a hypotonic solution containing detergent and propidium iodide, a DNA intercalating fluorescent stain. Aneuploidy as well as cytologic malignancy were found in 17 samples. Forty-seven samples had normal DNA histograms by FCM and were also cytologically negative. Four samples suspicious by cytology but normal by FCM were from patients with renal-cell carcinoma (two samples from the same patient), endometrial adenocarcinoma without metastasis and chronic lymphocytic leukemia. Three samples abnormal by FCM but negative by cytology were from patients with ovarian cystadenoma, cirrhosis and uterine leiomyoma. FCM showed aneuploidy in four cytologically negative samples from patients with histologically proven malignancy (lymphoma, colonic adenocarcinoma, cervical squamous cell carcinoma, and endometrial adenosquamous carcinoma). Based on these results, FCM analysis combined with conventional cytopathology yielded 100% sensitivity, 100% predictive value of a negative result and 94% specificity. This rapid and quantitative FCM analysis of body cavity fluids can be a very useful adjunct to conventional diagnostic cytopathology.     

The role of DNA flow and image cytometry in the evaluation of body cavity fluids

In addition to conventional cytomorphologic study, 50 body cavity fluid specimens (benign and malignant) were analyzed by both flow cytometry (FCM) and image cytometry (ICM) in order to evaluate the potential application of these techniques in the diagnosis of malignancy. While 88% of the fluids were similarly classified by FCM and ICM as being either diploid (66%) or nondiploid (22%), with similar DNA index values, nondiploid peaks were identified by ICM alone in 12% of the fluids. Aneuploid populations were present in 92% of the cytologically positive fluids and in 15% of the cytologically negative fluids. All of the latter fluids came from patients who clinically had tumors involving the respective body cavities. These results show that (1) both FCM and ICM are useful adjuvant techniques in the evaluation of body cavity fluid specimens and (2) ICM is superior to FCM in the identification of small aneuploid subpopulations. The identification of aneuploid populations by either method is highly suggestive of malignancy.     

Repeatedly nondiagnostic thyroid fine-needle aspirations do not modify malignancy risk

Objective: Thyroid nodules with nondiagnostic (ND) fine-needle aspirations (FNA) typically undergo repeat sampling. While repeat FNA is often diagnostic, little is known regarding the significance of repeatedly ND aspirates. Limited data suggest there is very low, if any, risk of malignancy for repeatedly ND FNAs. Study Design: We performed a retrospective analysis of ND thyroid FNAs over a nearly 6-year period at our institution to further address this question. Results: There were 834 ND thyroid FNAs, representing 694 distinct thyroid nodules. Repeat FNA was performed after an initial ND aspirate in 52% of cases (363/694); 19% (70/363) had at least one additional ND diagnosis on repeat FNA. Surgical follow-up was available for 57 cases. Malignancy was identified histologically in 21% (9/42) of nodules after a single ND FNA and in 20% (3/15) of nodules with 2 or more repeatedly ND aspirates. Accounting for all benign cytologic follow-up, the overall risk of malignancy was 4% [12/303; 3.5% (9/255) following a single ND FNA and 6.3% (3/48) after repeated ND FNAs]. Conclusion: We observed no modification of malignancy risk when repeated FNAs were ND. Clinical management for an ND aspirate should remain repeat aspiration along with clinical and sonographic correlation.     

Papillary carcinoma of the thyroid gland. Analysis of 94 cases with preoperative fine needle aspiration cytologic examination

From 1979 to 1983, 94 papillary carcinomas of the thyroid gland were examined histologically in our institute after a preoperative cytologic examination. Material for cytologic examination was obtained using fine needle aspiration (FNA) biopsy. Eighty-five (90.4%) of the 94 examined cytologic smears were representative. Among these 85 cases suspicion for malignancy or malignancy itself was found in 64 cases (75.3%). The remaining 21 smears, classified as cytologically not as suspect for malignancy, were reclassified and the previous diagnosis had to be revised in one case. In the other 20 cases no clue for malignancy could be demonstrated even after reexamination. In the 85 cases with representative cytologic findings, tumor size was determined on surgical material, in order to establish how many carcinomas with a diameter less than 3 cm could not be reached by FNA biopsy. Except for one case, all carcinomas with negative preoperative cytologic findings had a diameter less than or equal to 3 cm. The question arising is the possibility of improving the accuracy of FNA biopsy in tumor detection within cold nodules of the thyroid by combined use of scintigraphy and ultrasound-guided FNA biopsy.     

Fine needle aspiration cytology of thyroid gland diseases

From 1982 to 1987, 2,433 lesions of the thyroid gland in 1,796 patients were examined by fine needle aspiration (FNA). Cytopathology classified 66.91% of the aspirates as benign, 10.76% as thyroiditis, 4.89% as suspected (unspecified) neoplasia, 1.31% as positive for malignancy and 16.11% (392) as unsatisfactory. The histologic diagnoses in 257 cases were compared with cytologic diagnoses to determine the accuracy of FNA cytology of thyroid lesions, yielding a sensitivity of 71.43%, a specificity of 100% and an accuracy of 95.09%. This data strongly supports thyroid FNA as an important preoperative diagnostic tool. Follicular carcinomas were difficult to cytologically differentiate from nonmalignant follicular neoplasms, and papillary thyroid carcinomas less than 2 cm in diameter in elderly patients were frequently misdiagnosed or diagnosed only as "suspect lesion."     

Renal fine needle aspiration cytology

OBJECTIVE: To audit and evaluate the pitfalls in renal fine needle aspiration (FNA) cytology. STUDY DESIGN: A retrospective analysis of 180 renal FNAs from 163 patients, encountered at Canberra Hospital, Australian Capital Territory, between June 1989 and July 1997 was undertaken. The FNA procedures had been performed by radiologists under computed tomography (CT) or ultrasound (US) guidance. The study correlated the FNA results with biopsy findings and clinical outcome. RESULTS: The initial cytologic diagnoses included 84 (47%) benign, 6 (3%) atypical, 7 (4%) suspicious, 70 (39%) malignant and 13 (7%) inadequate. Six of the 13 cytologically inadequate group, on further investigation, had malignant histology. The benign cytologic categories contained 79 benign conditions and 5 cases with a malignant outcome. The atypical cytologic group contained 5 benign and 1 malignant case. All nine cytologically suspicious cases had malignant histology. The cytologically malignant group contained 62 malignant, 7 benign and 1 patient lost to follow-up. The sensitivity was 92.5%, specificity was 91.9%, positive predictive value was 89.9%, negative predictive value was 94.0%, and efficacy of the test was 92.2%. CONCLUSION: Renal FNA can provide an accurate diagnosis in most instances; however, aspiration cytology of the kidney has limitations and pitfalls. Low grade renal cell carcinoma has to be differentiated from oncocytoma, angiomyolipoma, renal infarct and reactive conditions. Renal FNA has a high negative predictive value, which is useful in reassuring patients with radiologically and cytologically benign lesions. Negative FNA does not exclude malignancy in the presence of a radiologic suspicion.     

Lymph node examination by fine needle aspiration in patients with known or suspected malignancy

In a series of more than 2,500 fine needle aspirates from multiple body sites, over 200 were clinically identified as lymph nodes from patients with known or suspected malignancy. The material was obtained using the easily manipulated Aspir-Gun with a 21-gauge or 22-gauge needle and syringe. Of the 200 lymph node specimens, 100 (50%) were cytologically reported as positive for malignancy. Ninety cases had surgical pathology specimens available for comparison with the fine needle aspiration (FNA) specimens. For the 88 of these cases with satisfactory FNA specimens, evaluation of the FNA results showed a predictive value of a positive result of 96.8%. These results compare favorably with those of surgical biopsy. The malignancies present in the lymph nodes included numerous adenocarcinomas from the breast, melanoma and pulmonary small-cell carcinoma. Six cases are briefly presented in which the FNA diagnosis was more problematic. While histologic examination of tissues or organs remains the desirable benchmark of comparison, the appropriate utilization of FNA cytology to guide therapy, particularly in a patient with previously diagnosed malignancy, may obviate the need for an open biopsy. The technique is convenient for patient and physician, useful for outpatients, relatively painless and provides good correlation between cytologic morphology and histopathology.     

Qualitative and quantitative analysis of peritoneal fluids from women with gynecologic diseases. Comparison of cytology and flow cytometry for the detection of malignancy in lavage and ascitic fluids

A prospective study was undertaken to compare flow cytometric (FCM) analysis to conventional cytologic evaluation for the detection of malignant cells in peritoneal fluids (peritoneal lavages and ascitic fluids) from women with gynecologic diseases. The 94 peritoneal fluids analyzed came from 63 cancer patients (with epithelial ovarian carcinomas) and 31 control patients (with benign gynecologic diseases). The FCM DNA histograms were generated using propidium iodide as a DNA fluorochrome. Samples for cytologic analysis were stained with the standard May-Grünwald-Giemsa or Papanicolaou stains. Of the 94 samples, 90 were evaluable cytologically while 70 were suitable for FCM analysis. The sensitivities were 55% for FCM DNA analysis and 80% for cytologic analysis. FCM DNA analysis had a 30% false-positive rate; cytologic analysis produced no false-positive results. These results indicate that there is no advantage in employing FCM analysis instead of conventional cytologic evaluation for the detection of malignant cells in peritoneal fluids from gynecologic cases.     

Fine needle aspiration of the liver

A total of 81 transhepatic fine needle aspiration (FNA) biopsies were performed on 78 patients to rule out focal or diffuse neoplastic disease; 87.6% were performed with ultrasound guidance, 6.1% with CT guidance, 3.7% intraoperatively and 1 using fluoroscopy during percutaneous transhepatic cholangiography. Smears of the aspirated samples were cytologically evaluated with clinical and radiologic correlation; in addition, histologic examination of cell blocks was performed in 46% of the cases, ultrastructural examination in 34% of the cases and peroxidase-antiperoxidase staining in 3 cases. Ultrastructural definition of the type of malignancy was possible in 24 cases (29%). Minor complications in two patients were pain and tenderness at the puncture site. The sensitivity for malignancy was 91%, the specificity was 100%, the predictive value of positive results was 100%, and the predictive value of negative results was 73%. This series demonstrates that FNA biopsy with ultrasound guidance can provide an accurate diagnosis of malignancy and may preempt a lengthy workup in the search for a primary tumor.     

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 in the diagnosis of sinuses and ulcers of the body surface (skin and tongue)

Both fine needle aspiration (FNA) and conventional scraping were used to obtain cytodiagnostic samples from ulcers and sinuses of the skin (18 cases) and tongue (3 cases). These included 14 cases of tuberculosis, 5 squamous-cell carcinomas and 2 cases of nonspecific infection. The FNA smears contained characteristic tuberculous granulomas or epithelioid cells in 10 of the 14 tuberculosis cases and ample diagnostic material in 4 of the 5 carcinoma cases; in contrast the scraping smears predominantly contained necrotic material on which a diagnosis was not possible. Of the 19 cases of tuberculosis and malignancy, 12 were diagnosed only by FNA, 6 were diagnosed by both methods and the FNA sample was negative while the scrape was positive in 1 case. Hence, the diagnosis was made in 18 of 19 by FNA cytology, but in only 7 of 19 cases by scraping cytology, strongly indicating the diagnostic superiority of the former in diagnosing many lesions of the body surface.     

Stereotaxic fine needle aspiration cytology of clinically occult malignant and premalignant breast lesions

Stereotaxic fine needle aspiration (FNA) cytology was used to study clinically occult (nonpalpable) breast lesions in 114 consecutive patients with mammographically suspicious findings prior to excisional biopsy. The aspirate contained insufficient material for cytologic evaluation in 15 cases (13.2%), which were histologically diagnosed as benign (7 cases), atypical hyperplasia (7 cases) or carcinoma in situ (1 case). The cytologic findings indicated a benign lesion in 77 cases (67.5%), which were histologically diagnosed as benign (71 cases) or atypical ductal hyperplasia (6 cases). The cytologic sample showed atypia in eight cases (7.0%), which were histologically diagnosed as severe atypical ductal hyperplasia (three cases), carcinoma in situ (one case) or proliferative fibrocystic disease (four cases). In the eight cases (7.0%) cytologically interpreted as probably malignant, histology confirmed six invasive carcinomas, one carcinoma in situ and one fibrocystic disease. Of six cases (4.4%) cytologically reported as malignant, five were histologically diagnosed as invasive carcinoma and one as carcinoma in situ. Overall, stereotaxic FNA cytology reported as malignant or probably malignant 14 of the 15 cases with a histologic confirmation of malignancy, for a sensitivity of 93.3%. Cytology correctly identified 78 of the 83 histologically negative cases, for a specificity of 94.0%. The 16 cases histologically diagnosed as ductal hyperplasia, which carries a high risk for subsequent malignancy, were studied in detail in an effort to define histologic and cytologic criteria for this entity. Using selected histologic criteria, 11 of these cases were graded as showing mild-to-moderate atypical hyperplasia and 5 as showing severe atypical hyperplasia. Three of the latter cases were similarly identified by an analogous cytologic grading; the other two cases had insufficient cytologic samples. The total results in this series of 114 cases support the use of stereotaxic FNA cytology in the diagnosis of these nonpalpable breast lesions, examples of which are illustrated. In particular, it may help to raise the low specificity yielded by mammography alone, which would represent a significant advance for the patient in terms of the accuracy, expediency and reduced cost of diagnosing these lesions.     

Analysis of KIT mutation and protein expression in fine needle aspirates of gastrointestinal stromal/smooth muscle tumors

OBJECTIVE: To determine if sequencing the KIT gene could facilitate more definitive FNA diagnosis. STUDY DESIGN: Sixteen cases of gastrointestinal stromal/smooth muscle tumor (GIST) in which fine needle aspiration (FNA) was performed (mean age, 67; M/F = 12/4) were studied. DNA was extracted from cytologic preparations from all patients (15 cell blocks, 1 alcohol-fixed smear) and seven subsequent resection specimens. DNA was amplified by polymerase chain reaction, using primers designed to amplify a segment of the KIT gene exon 11 and sequenced on an ABI Prism 377 DNA sequence analyzer (Applied Biosystems, Indianapolis, Indiana, U.S.A.). Immunocytochemical staining for CD 117 (the KIT gene product) was performed on sections from 12 cell blocks and 7 surgical resections. RESULTS: In-frame deletion of exon 11 was detected in eight cases (7 monoalleic, 1 bialleic); a point mutation was found in one case. Mutation was found only in histologically malignant (6 of 10 cases) and borderline GISTs (3 of 4 cases). No mutation was identified in benign tumors. In three cases, scant cellularity or blood precluded sequencing. CD 117 was expressed in 12 of 15 cases. CONCLUSION: Immunocytochemical staining for CD 117 is useful in confirming a cytologic diagnosis of GIST but does not facilitate diagnosis of malignancy. FNA biopsy specimens are suitable for KIT gene sequencing; detection of a KIT mutation favors a malignant diagnosis, though absence of mutation does not preclude malignancy.     

Accuracy of cytologic interpretation of pancreatic neoplasms by fine needle aspiration and pancreatic duct brushings

OBJECTIVE: To investigate the accuracy of fine needle aspiration (FNA) specimens and pancreatic duct brushings in the detection of pancreatic lesions and to compare the results with follow-up biopsy and/or surgical interpretation. STUDY DESIGN: We reviewed a total of 57 specimens (37/20), 37 FNA specimens and 20 pancreatic duct brushings, from 45 patients treated at Froedtert Memorial Lutheran Hospital, affiliated with the Medical College of Wisconsin, Milwaukee, over a 4-year period. The FNA and brushing samples were categorized as follows: positive for malignancy (21/3 = 24), suspicious for malignancy (8/7 = 15) and atypical (8/10 = 18). The results were then correlated with the tissue diagnosis. RESULTS: The 24 cytologic samples positive for malignancy included 23 (20/3) pancreatic ductal carcinoma (CA) and 1 (1/0) neuroendocrine CA; in the suspicious category, 11 (6/5) were pancreatic ductal CA; 2 (0/2) mucinous neoplasms and (2/0) neuroendocrine neoplasms; in the atypical category; 2 (2/0) suggestive of mucinous neoplasia, 1 (1/0) suggestive of serous neoplasia and 9 (2/7) favor reactive; and 6 (3/3) without further categorization. Tissue diagnoses were available in 26 cases: 12 (10/2) cases positive for malignancy, 8 (5/3) suspicious for malignancy and 6 (5/1) atypical. The 12 cytologically positive cases confirmed by histology showed 10 ductal CA, 1 neuroendocrine CA and 1 negative. All 8 cases (100%) suspicious for malignancy revealed positive results, including 5 ductal CA, 1 neuroendocrine neoplasm, 1 mucinous cystic neoplasm and 1 lymphoma. Of the 6 atypical lesions, 1 showed ductal CA, 2 mucinous cystic neoplasm and 3 chronic pancreatitis. CONCLUSION: Pancreatic FNA and duct brushings [table: see text] are accurate methods in identifying pancreatic lesions, particularly ductal CA. Accuracy can be improved in the case of mucinous and other lesions with adequate cellularity of the smear and recognizing the limitations of brush samples in the case of mucinous cystic lesions. False negative results may occur in cases of poor representation of malignant cells or poor sampling.     

Cytologic diagnosis of reactive lymphadenopathy in fine needle aspiration biopsy specimens

Reactive or benign lymphadenopathies were cytologically diagnosed in the aspirates of 62 (23.5%) of 265 cases with enlarged lymph nodes of the head, neck or inguinal region subjected to fine needle aspiration (FNA) biopsy. The cytomorphologic features characteristic of reactive lymphadenopathy are described in detail; some of the cell patterns were suggestive of a specific disease process. The similarities of cells and cell patterns that may pose differential diagnostic problems with malignant lymphomas are pointed out. This study emphasizes the role of FNA cytology in the diagnosis of some benign conditions.     

Comparison of DNA ploidy in routine fine needle aspiration biopsy samples and paraffin-embedded tissue samples

The nuclear DNA content was determined by flow cytometry (FCM) from unfixed fine needle aspiration (FNA) biopsy samples of 31 human tumors, and from the same tumors after their excision, fixation with formalin and embedding in paraffin. The ploidy of the histograms was the same in 29 (94%) of the 31 cases. The disagreement in two cases may be explained by clonal heterogeneity of the tumors. The DNA index of the aneuploid cases was identical in fresh and fixed samples. The coefficient of variation of the diploid peaks (P less than .001) and the mean percentage of S-phase cells (P = .06) were larger in the fixed samples. It is concluded that routine FNA biopsy is a practical and reliable method for collecting cells for FCM DNA ploidy determination.     

The role of fine needle aspiration cytology in the diagnosis of lymphoma

The accuracy of fine needle aspiration (FNA) cytology for the diagnosis of lymphoma and other hematolymphoid malignancies was investigated by a review of 158 FNA specimens from 143 patients. Patients included in the study had either a diagnosis of a hematolymphoid malignancy by FNA cytology or a biopsy diagnosis of lymphoma that was preceded by FNA cytology. Biopsy specimens were obtained from 85% of the patients. Of the 158 needle aspirates, 118 (75%) were diagnosed as lymphoma, 13 (8%) as suspicious of lymphoma, 8 (5%) as myelomas, 3 (2%) as leukemias, 12 (8%) as positive for malignancy and 4 (2%) as negative for malignancy. Two of the 118 needle aspirates diagnosed as lymphoma were false positives while 3 of 13 diagnosed as suspicious for lymphoma were found to be benign. Overall, there were four false negatives. Morphologic subclassification of the lymphomas, originally attempted for 60 needle aspirates, was identical to the histologic subclassification in 51 cases (85%). FNA cytology provided the initial diagnosis of a hematolymphoid malignancy in 51% of the cases and allowed the documentation of recurrent disease in 49%. The results demonstrate the usefulness of FNA cytology for the diagnosis and management of patients with lymphoma.