Studies on the mechanism of insulin resistance in the liver from humans with noninsulin-dependent diabetes. Insulin action and binding in isolated hepatocytes, insulin receptor structure, and kinase activity.

We have developed a method to isolate insulin-responsive human hepatocytes from an intraoperative liver biopsy to study insulin action and resistance in man. Hepatocytes from obese patients with noninsulin-dependent diabetes were resistant to maximal insulin concentration, and those from obese controls to submaximal insulin concentration in comparison to nonobese controls. Insulin binding per cell number was similar in all groups. However, insulin binding per surface area was decreased in the two obese groups because their hepatocytes were larger. In addition, the pool of detergent-extractable receptor was further decreased in diabetics. Insulin receptors in all groups were unaltered as determined by affinity-labeling methods. However, insulin-stimulated insulin receptor kinase activity was decreased in diabetics. Thus, in obesity, decreased surface binding could explain resistance to submaximal insulin concentrations. In diabetes, diminished insulin-stimulated protein kinase activity and decreased intracellular pool of receptors could provide an explanation for postinsulin-binding defect(s) of insulin action in human liver.

Accelerated coronary vascular disease in the heart transplant patient: coronary arteriographic findings.

Annual coronary arteriograms have been obtained from all heart transplant recipients at Stanford University Medical Center since 1969. Angiographic lesions in 81 transplant patients exhibiting coronary vascular disease were classified into three categories: type A, discrete or tubular stenoses; type B, diffuse concentric narrowing; and type C, narrowed irregular vessels with occluded branches. The 81 arteriograms showing transplant coronary vascular disease were contrasted with 32 from nontransplant patients with coronary artery disease analyzed in a similar fashion. The nontransplant angiograms showed 178 lesions, all of type A (discrete or tubular) morphology, 75% of which were located in primary epicardial coronary vessels and 25% in secondary branch vessels. In the patients with transplant coronary vascular disease, 349 (76%) of 461 lesions were type A: 57% in primary vessels, 42% in secondary branches and 1.4% in tertiary branches. Of the 112 type B and C lesions (diffuse narrowing, tapering and obliteration), 25% were in primary vessels, 44% in secondary vessels and 31% in tertiary branches (p less than 0.05 for patients with transplant coronary vascular disease versus patients with nontransplant coronary artery disease). Total vessel occlusion was found in proximal or middle vessel segments in 96% and distally in 4% of patients with "ordinary" coronary artery disease versus 49% distally in patients with transplant coronary disease (p less than 0.002). In the presence of total vessel occlusion, collateral vessels were poor or absent in 92% of transplant versus 7% of nontransplant patients with coronary disease (p less than 0.002). Therefore, coronary artery disease in transplant patients represents a mixture of typical atheromatous lesions and unique transplant-related progressive distal obliterative disease that occurs without collateral vessel development.

Correlations among p53, Her-2/neu, and ras overexpression and aneuploidy by multiparameter flow cytometry in human breast cancer: evidence for a common phenotypic evolutionary pattern in infiltrating ductal carcinomas.

Human solid tumors develop multiple genetic abnormalities that accumulate progressively in individual cells during the course of tumor evolution. We sought to determine whether there are specific sequences of occurrence of these progressive evolutionary changes in human breast cancers by performing correlated cell-by-cell measurements of cell DNA content, p53 protein, Her-2/neu protein, and ras protein by multiparameter flow cytometry in 56 primary tumor samples obtained at surgery. In addition, p53 allelic loss and Her-2/neu gene amplification were determined by fluorescence in situ hybridization in cells from the same samples. We reasoned that if there is a specific order in which genetic changes occur, the same early changes would be found consistently in the cells with the fewest abnormalities. We reasoned further that late-developing abnormalities would not occur alone in individual cells but would almost always be found together with the early changes inherited by the same cells. By these criteria, abnormalities involving p53 generally occurred early in the course of development of invasive breast cancers, whereas ras protein overexpression was found to be a late-occurring phenomenon. Within individual tumors, cellular p53 overexpression was often observed alone in individual cells, whereas ras protein overexpression was rarely observed in the absence of p53 overexpression and/or Her-2/neu overexpression in the same cells. Furthermore, the intracellular level of each abnormally expressed protein was found to increase progressively as new abnormalities were acquired. Infiltrating ductal carcinomas exhibited characteristic phenotypic patterns in which p53 allelic loss and/or p53 protein overexpression, Her-2/neu amplification and/or overexpression, aneuploidy, and ras overexpression accumulated within individual cells. However, this pattern was not a prominent feature of lobular breast cancers. All six lobular breast cancers studied were diploid. p53 allelic loss and/or early p53 overexpression, and late ras cooverexpression in the same cells were less common in lobular breast cancers than in infiltrating ductal carcinomas. Although Her-21neu overexpression was a common finding in lobular breast cancers, Her-2/neu amplification was not observed in these tumors.

Coronary bypass surgery for unstable angina pectoris. Clinical follow-up and results of postoperative treadmill electrocardiograms.

The first 81 patients who underwent coronary artery bypass surgery at Stanford University Hospital for unstable angina pectoris have been followed up for an average of 18 months. The over-all surgical mortality was 8.6 per cent (seven patients). There have been no operative deaths in last 32 patients, which may be due to over 75 per cent of these patients being stabilized on intensive medical therapy from 24 to 72 hours before study or surgery. There was a 16 per cent (13 patients) perioperative and 15 per cent (12 patients) late incidence of myocardial infarction. Of 74 patients who survived the initial operation 2 died 2 and 3 months postoperatively. Good or complete relief from pain was obtained in 94 per cent (70 patients) of the survivors. Of 57 longterm survivors tested, 49 per cent (28 patients) had a definite ischemic response to treadmill exercise testing. This may reflect the severe nature of the occlusive coronary disease or mechanisms other than increased coronary flow being responsible for the relief of pain. Although coronary bypass surgery appears to be effective in relieving the pain of patients with unstable angina pectoris, the 18 month average follow-up indicates that the incidence of myocardial infarction in surgically treated patients is comparable to that in medically treated patients.

Localized primary (AL) amyloid tumor of the breast. Cytologic, histologic, immunocytochemical and ultrastructural observations.

Two examples of localized primary amyloid tumor of the breast are presented, including one patient with metachronous bilateral lesions. Our findings and review of the literature indicate that this rare lesion occurs predominantly in elderly females and can be mammographically and clinically confused with carcinoma. Fine-needle aspiration biopsy can be a useful procedure to make a preliminary diagnosis. Congo red staining with prior potassium permanganate incubation confirmed the AL type of amyloid in our two cases; this might be the predominant type in the localized form involving the breast. Immunofluorescence studies demonstrated IgA, with kappa and lambda light-chain deposition within the amyloid foci in one case, and intracytoplasmic IgG with both light chains within plasma cells and amyloid deposits of the second case. Ultrastructural examination of one of the cases showed characteristic findings of straight, nonbranching fibrils of 4-9 nm, diagnostic of amyloid. From our findings and a review of the literature, we conclude that amyloid tumors of the breast can occur in three separate settings: secondary amyloidosis, systemic or multiple myeloma associated amyloidosis, and as a localized primary type having a benign course.

Pediatric thyroid nodules: disease demographics and clinical management as determined by fine needle aspiration biopsy.

OBJECTIVE: The prevalence of thyroid nodularity in children has been estimated to be 1.8%. The reported prevalence of specific diseases which comprise these nodules is conflicting as evidenced by a reported range of malignancy of 2 to 50% in solitary nodules. In order to better classify pediatric (< 18 years old) thyroid disease and evaluate the utility of fine needle aspiration biopsy (FNAB) in this patient population, we retrospectively reviewed 66 FNABs from 64 thyroid nodules and 2 perithyroid lymph nodes from 57 patients. PATIENTS: The study was composed of 8 males and 49 females who ranged in age from 1 to 18 years old (mean = 13.1). DESIGN: Surgical and/or clinical follow-up was obtained in all patients. The 66 FNAB diagnoses were initially classified into specific diseases. However, for the purpose of this review, the cases were classified as: 3 insufficient, 51 benign, 8 suspicious, and 4 malignant. RESULTS: There were no "false positives" and one "false negative" (a papillary carcinoma was misdiagnosed as a benign nodule). Overall, 10 patients (18%) had malignant thyroid lesions, including 8 papillary carcinomas and 2 follicular carcinomas. Benign diagnoses included benign nodule, cyst, lymphocytic thyroiditis, granulomatous thyroiditis, hyperplasia, and abscess. CONCLUSIONS: The prevalence of malignancy in pediatric patients with thyroid nodules was 18%. We conclude that, because of its high diagnostic accuracy and minimal invasiveness, FNAB is useful in the management of pediatric thyroid nodules.

Interruption of the aortic arch: preoperative and postoperative clinical, hemodynamic and angiographic features.

Interruption of the aortic arch, studied in 10 patients, was associated with a variety of other cardiac anomalies in 8 patients and was an isolated anomaly in 2. Clinical and angiographic evaluation in the former group revealed congestive heart failure and generalized cyanosis in early infancy, pulmonary and systemic arterial hypertension and a variety of intracardiac and aortic shunt. The two patients with an isolated anomaly had clinical and hemodyanmic features not dissimilar from those of severe coarctation but interruption of the aortic arch was demonstrated on aortography. Surgical treatment was successful in four of the eight infants with associated anomalies and in both children with the isolated defect. Postoperative angiography revealed several related complications and the status of the aortic reconstruction. Clinical angiographic recognition of this lesion is important because operative intervention has been successful in an increasing number of patients.

Clinical and arteriographic features of Prinzmetal's variant angina: documentation of etiologic factors.

Coronary arteriography performed in 17 patients with Prinzmetal's variant angina demonstrated high grade fixed obstructions in 9 patients (Group I) and insignificant or no fixed lesions in 8 patients (Group II). Group I consisted mostly of middle-aged or elderly men with S-T segment elevations in various sites; Group II included five younger women with S-T segment elevations in inferior electrocardiographic leads. In Group I patients, arteriography revealed a discrete high grade lesion located proximally in a major coronary artery in four patients and multivessel involvement in five patients. In Group II patients, spontaneous spasm was documented in three patients and spasm was pharmacologically provoked in two others during arteriography. The current study indicates that spasm is the responsible pathogenetic mechanism of myocardial ischemia in some patients with Prinzmetal angina and that this mechanism may be suspected from the clinical characteristics of these patients.

Coronary arterial narrowing in Takayasu's aortitis.

A patient with Takayasu's aortitis and angina pectoris due to severe narrowing of the right and left coronary arterial ostia is described. Takayasu's arteritis produces a panaortitis, with thickening of the adventitia predominating, and an inflammatory cell infiltrate involving the adventitia, outer media and vasa vasorum. Narrowing of the coronary arteries in this disease is due to extension into these arteries of the processes of proliferation of the intima and contraction of the fibrotic media and adventitia that occur in the aorta. The distal coronary arteries usually do not manifest arteritis and are normal in caliber. Angina pectoris may be the first symptom of the disease if the coronary arteries are the initial site of severe arterial narrowing. The coronary arterial bypass graft operation is effective therapy for treating coronary arterial narrowing due to Takayasu's arteritis.

KRAS oncogene mutations suggest a common histogenetic origin for pleomorphic giant cell tumor of the pancreas, osteoclastoma of the pancreas, and pancreatic duct adenocarcinoma.

Giant cell neoplasms of the pancreas are rare tumors of uncertain histogenesis. Mutation of the KRAS oncogene is common in typical pancreatic duct adenocarcinoma. We have analyzed DNA from five pancreatic tumors with giant cells for mutations in the KRAS oncogene and found alterations of the second position of codon 12 in each case (four G > A transitions and one G > C transversion). The common mutation pattern in tumors with giant cells and duct adenocarcinoma suggests a common route to malignant transformation and may indicate a shared histogenesis. We also tested 11 cases of malignant fibrous histiocytoma, a histological mimic of pleomorphic giant cell tumor, for mutations in the KRAS oncogene. The absence of KAS mutations in each of the malignant fibrous histiocytomas (MFHs) and in other histologically similar tumors may provide assistance in the differential diagnosis of pleomorphic pancreatic tumors.

Systematization of primary histopathologic and fine-needle aspiration cytologic features and description of unusual histopathologic features of neuroblastic tumors: a report from the Pediatric Oncology Group.

On the basis of a detailed review of the primary histopathologic features of 239 cases and the fine-needle aspiration cytologic features of seven cases, a systematized schema of differentiation, progressive maturation and organization, and biologic behavior in neuroblastic tumors (NTs) is presented. The differentiation is of the gangliocytic and schwannian lineages. Maturation occurs in differentiating neuroblasts, leading to the formation of various stages of ganglion cells and Schwann cells. Organization is characterized by nesting pattern, rosette formation, parallel arrangement of neuropil, and alignment of Schwann cells along the neurites. According to this schema the NTs can be arranged in the following order: undifferentiated, poorly differentiated, and differentiating neuroblastoma; nodular, intermixed, and borderline ganglioneuroblastoma; and ganglioneuroma. Formulation of such a schema is helpful in gaining a better understanding of the complex pathologic features and in defining the criteria for various types of NTs. Therefore, the schema also would be helpful in achieving uniformity and reproducibility of the diagnosis of various types of NTs. Previously unreported features related to shape, size, nucleus, and cytoplasm of neuroblasts; secondary changes and patterns; changes in the fibrovascular septa; and other morphologic aspects of NTs and features (such as large tumor cells, karyorrhectic cells in fine-needle aspiration biopsy, tumor giant cells, anaplasia, and nesting pattern of tumor cells that have not been sufficiently emphasized) also are described. The importance of these previously unreported and insufficiently emphasized features relates to the histologic and cytologic diagnosis of NTs. For example, some of the features, such as starry sky appearance and spindle-shaped neuroblasts, may be misleading if seen in a small biopsy specimen. Others, such as tumor giant cells resembling ganglion cells and nesting pattern, will provide clues to the correct diagnosis. Some of the features, such as sclerosing pattern, hyalinization, and dense lymphoplasmacytic infiltration, may be related to the phenomenon of regression exhibited by neuroblastomas.

The clinical application and cost analysis of fine-needle aspiration biopsy in the diagnosis of mass lesions in sarcoidosis.

BACKGROUND: Sarcoidosis is a prevalent disease of unknown cause characterized by granulomatous inflammation that often creates deep and/or superficial mass lesions. Tissue samples are considered the "gold standard" in diagnosis; however, it is a medically treated disease. We analyzed the utility and relative cost-effectiveness of fine-needle aspiration biopsy (FNAB) in the clinical investigation of patients with both suspected and unsuspected sarcoidosis. METHODS: All FNAB cases with sarcoidosis either as the cytologic diagnosis or mentioned as part of the differential diagnosis were retrospectively reviewed for clinical history, follow-up, cytologic features, and surgical pathology findings. Comparative analysis of cost of FNAB and excisional biopsy were also made. RESULTS: Thirty-two FNABs in 28 patients included 17 women and 11 men. Anatomic sites included lymph node (n = 17), lung (n = 5), salivary gland (n = 8), and liver (n = 2). Sarcoidosis had already been diagnosed or was a clinical consideration prior to FNAB in 14 cases. Chest radiograph showed abnormal findings in 19 cases. Angiotensin-converting enzyme (ACE) was measured in seven patients and was elevated in four. All aspirates showed granulomatous inflammation; in 22 patients, special stains or cultures for microorganisms were negative. Simultaneous or subsequent excisional biopsies confirmed the FNAB findings in 17 patients. Institutional ratios of excisional biopsy to FNAB in the diagnosis of sarcoidosis ranged from 4 to 19:1. The cost of FNAB was only 12.5 to 50% that of tissue biopsy. CONCLUSIONS: FNAB appears to be underutilized in the diagnosis of sarcoidosis. When used in conjunction with radiologic and laboratory data, FNAB may be a reliable and cost-effective method of diagnosis, especially in patients with an established diagnosis of sarcoidosis.

Intensive care for the elderly: outcome of elective and nonelective admissions.

Survival, quality of life, and need for continuing medical care were evaluated for 134 elderly patients admitted to the intensive care units (ICU) at Stanford University Hospital and for a control group. Of the patient group, 57.5% were admitted to the ICU following elective surgery; 42.5% were emergency surgical and medical patients. Hospital mortality was 3.9% for elective and 22.8% for nonelective patients; 18-month mortality was 13.0% and 47.4%, respectively. Fifty-nine patients (60.8% of survivors) completed follow-up questionnaires. Subjective and objective quality of life was good. Quality of life was slightly worse for ICU survivors than for controls; elective and nonelective patients did not differ significantly. Although the cost of ICU hospitalization was high, additional medical care was not excessive. Nonelective patients required more continuing care than elective patients, and both groups required more than controls.

Extramedullary hematopoietic ascitic fluid cytology in myelofibrosis.

A patient having myelofibrosis with myeloid metaplasia complicated by ascites is reported. Cytologic examination of the Papanicolaou-stained smears of the ascitic fluid revealed megakaryocytes and granulocytes of varying maturity, including eosinophils and reactive mesothelial cells. Autopsy examination demonstrated extensive involvement of the omentum and peritoneal surfaces by extramedullary hematopoiesis. The most likely mechanism of the ascites is multicentric ectopic extramedullary hematopoiesis with exfoliation of the characteristic cells into the peritoneal space.

Immunocytochemical panel for the identification of malignant cells in serous effusions.

The cytologic diagnosis of malignancy in serous effusions can be challenging. An immunocytochemical (ICC) panel using commercially available antibodies (to carcinoembryonic antigen [CEA], epithelial membrane antigen [EMA], B72.3, Leu-M1, cytokeratin [CK], leukocyte common antigen [LCA], S-100 protein, and vimentin) was applied to cell blocks fixed in methyl Carnoy's solution that were from 55 consecutive pleural, peritoneal, and pericardial fluid specimens. The results were correlated with data from clinical records and routine cytologic studies. Final cytologic diagnoses included 26 of adenocarcinoma and 1 of mesothelioma. The remaining 28 cases were considered to be benign (reactive) proliferations. EMA, CEA, B72.3, and Leu-M1 were present in 96%, 77%, 58%, and 42% of adenocarcinomas, respectively. These determinants were absent in the mesothelioma and the reactive effusions, although anti-CEA yielded strong background staining of inflammatory cells. The CK markers identified malignant cells in 93% of cases, but consistently stained mesothelial cells as well. Antivimentin strongly labeled mesothelial cells in all cases, with weak to absent staining of malignant cells. In 3 of 26 carcinoma cases (12%), the ICC panel identified malignant cells that were not recognized initially on routine cytologic examination. In 1 of 26 cases (4%), the panel was falsely negative. Use of this approach can improve the diagnostic accuracy of cytologic examination of serous fluids. The ICC panel is especially helpful when atypical mesothelial proliferation is present, or in cases that are clinically suspect for malignancy, but cytologically negative because there are only a few malignant cells, or those that are cytologically bland.

The cost-effectiveness of the cytology laboratory and new cytology technologies in cervical cancer prevention.

The effect of changes in cytology laboratory costs, including the costs of new technologies, on the cost-effectiveness of cervical cancer prevention has not been studied. Using University of Iowa laboratory detection rates and costs, a decision model determined the cost-effectiveness of the laboratory with and without new technologies. Compared with not performing a cervicovaginal smear, the cost to increase the discounted life expectancy per patient by 1 year was $2,805 for the laboratory component alone and $19,655 for the entire cervical cancer prevention strategy. In moderate- to high-risk women, cervical cancer screening was cost-effective even at high cytology laboratory costs (eg, $75 per smear). New technologies were cost-effective only if they resulted in a substantial increase in the detection of high-grade squamous intraepithelial lesions (eg, an additional 236 high-grade squamous intraepithelial lesions per 10,000 women). New technologies have not demonstrated these increased detection rates.

Fine-needle aspiration biopsy of pulmonary coccidiodomycosis. Spectrum of cytologic findings in 73 patients.

Coccidioides immitis, the causal agent of coccidiodomycosis, is endemic in the arid desert regions of Mexico and the southwestern United States. Individuals may acquire the disease through the inhalation of conidia. The majority of infected patients are asymptomatic or exhibit flu-like symptoms. Two percent of infected individuals ultimately demonstrate a solitary pulmonary nodule that may be radiographically indistinguishable from neoplasms or other infectious lesions. This report describes the spectrum of cytologic findings in 73 patients who were diagnosed with pulmonary coccidiodomycosis by fine-needle aspiration (FNA) biopsy. The patients ranged in age from 30 to 92 years. Ten had a previous history of malignancy. The smears were characterized by a large amount of granular, eosinophilic debris with a paucity of acute or chronic inflammation. Granulomatous inflammation was present in only three cases. The diagnosis was confirmed by the cytologic observation of C. immitis spherules that ranged in size from approximately 20 to 200 microns. Many of these spherules had a crushed or fractured appearance, and occasional calcified forms were seen. Endospores were observed in intact spherules and were rarely observed outside these spherules. Mycelial elements occasionally were present. C. immitis were cultured in 9 of 44 cases in which fungal cultures were obtained. The cytologic differential diagnosis, which includes contaminant, other infectious diseases and malignancies, is discussed.

Bronchoalveolar lavage cytology in pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis (PAP) is an uncommon disease in which alveoli are progressively filled with surfactant-related material. Although a definitive diagnosis is usually made by an open lung biopsy, bronchoalveolar lavage (BAL) cytology may play a decisive role in the clinical work-up of these patients, and, in some cases, may spare a patient a more invasive diagnostic procedure. The authors present three patients in whom BAL cytology specimens contained the characteristic (although not specific) globules of amorphous proteinaceous PAS-positive material accompanied by only rare background macrophages and inflammatory cells. The patients include a 40-year-old man with an 8-year history of fever of unknown origin, a 30-year-old man with a chronic nonproductive cough, and a 6-year-old boy diagnosed at 5 months of age with osteopetrosis and hypogammaglobulinemia who subsequently developed a disseminated Mycobacterium avium-intracellulare infection. All specimens stained with Gomori methenamine silver (3) and Ziehl-Neelsen (2) were negative for microbial organisms, Ultrastructural examination of two specimens revealed the characteristic lamellar structures of surfactant, increasing diagnostic specificity. Lung biopsies and/or autopsy subsequently confirmed the diagnosis in all three cases. The characteristic cytologic and ultrastructural features of PAP in BAL specimens are presented along with the morphologic differential features of other entities which potentially could be confused with PAP.

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.

Parathyroid hormone (PTH) assay of parathyroid cysts examined by fine-needle aspiration biopsy.

The authors report three cases of parathyroid cysts examined by the fine-needle aspiration biopsy technic. A presumptive diagnosis of parathyroid cyst was made when characteristic water-clear fluid was aspirated. The diagnosis was then confirmed by parathyroid hormone (PTH) assay. The authors believe that the C-terminal/midmolecule determination should be the assay of choice, because the N-terminal-specific assay gave normal or slightly elevated results in all the cases studied. If only an N-terminal-specific PTH assay is obtained, potential for a false negative diagnosis exists. With a correct PTH assay, a specific diagnosis of parathyroid cyst can be rendered, which enables appropriate treatment of total fluid aspiration, which thereby eliminates the need for thyroid hormone treatment or surgery in most cases. A discussion of PTH assays is presented along with speculations concerning the secretion of PTH by the parathyroid gland. The previous literature detailing cytologic findings and the PTH assays of parathyroid cysts diagnosed by the fine-needle aspiration biopsy are reviewed.