Karyometric marker features in fine needle aspirates of follicular adenoma of the thyroid

Karyometric measurements were performed on fine needle aspirates of clearly identifiable adenomatous areas and adjacent normal-appearing areas in the surgical specimens from ten patients with follicular adenomas of the thyroid. Similar measurements were made on aspirates from nine patients free of thyroid disease. A total of 95 karyometric features were evaluated for each nucleus. Analysis of variance of optical density values did not show a significant difference between the three types of nuclei. Discriminant analysis selected seven karyometric features that produced a statistically highly significant separation of adenoma nuclei from control nuclei. A similar analysis selected six features that produced a statistically highly significant discrimination of normal-appearing nuclei from control nuclei. The validity of these markers for distinguishing control nuclei from adenoma nuclei and normal-appearing nuclei adjacent to adenomas was demonstrated by analysis in further training and test sets. These findings parallel those previously demonstrated for invasive and microinvasive follicular carcinomas of the thyroid.     

Karyometric marker features in fine needle aspirates of invasive follicular carcinoma of the thyroid.

Karyometric measurements were performed on fine needle aspirates of clearly identifiable tumor areas and adjacent normal-appearing areas in the surgical specimens from ten patients with invasive follicular carcinoma of the thyroid. Similar measurements were performed on aspirates from nine patients free of thyroid disease (controls). A total of 95 karyometric features were evaluated for each nucleus. Analysis of variance of optical density values indicated (1) a similarity between tumor and normal-appearing nuclei from carcinoma cases, (2) a significant difference between those nuclei and control nuclei and (3) that most of the differences were due to the differences of tissue origin. Stepwise linear discriminant analysis selected ten features that produced a statistically highly significant separation of tumor nuclei from control nuclei. A similar analysis selected six features that produced a statistically highly significant discrimination of normal-appearing nuclei from control nuclei; the validity of those karyometric features as markers of malignancy in normal-appearing nuclei from tissues adjacent to invasive follicular carcinomas of the thyroid was demonstrated by analysis in further training and control sets of nuclei. This analysis in thyroid aspirates identified more marker features than did a previous similar analysis using tissue sections.     

Computerized morphometric study on fine needle aspirates of cellular follicular lesions of the thyroid

OBJECTIVE: To investigate the value of computerized nuclear morphometry in the differential diagnosis of cellular follicular lesions of the thyroid cytologically diagnosed on fine needle aspiration (FNA) smears. STUDY DESIGN: Sixty cases of FNA thyroid smears were cytologically diagnosed and classified as follows: 30 cases of follicular carcinoma, 20 cases of cellular hyperplastic nodules and 10 cases of follicular adenoma. Using an image analysis system, two morphometric variables, nuclear area and major axis length of the nucleus, were measured for each case. RESULTS: For both nuclear morphometric variables, statistical differences were found between carcinomas and hyperplastic nodules as well as between carcinomas and adenomas. No statistical differences were found between the nuclear variables in either hyperplastic nodules or adenomas. CONCLUSION: The results confirm the aim of our study, to establish nuclear morphometry by computerized image analysis as an additional tool in the differential diagnosis of thyroid follicular lesions cytologically diagnosed on FNA smears.     

Morphometric studies on nuclei in smears of fine needle aspirates from oxyphilic tumors of the thyroid

Morphometry was applied to smears of fine needle aspirates from 26 oxyphilic thyroid neoplasms. Thirteen tumors were considered benign as judged from histologic findings and clinical follow-up for 2 to 20 years after the operation. Thirteen tumors were considered malignant histologically; four of these had proven metastases. In each case the mean and standard deviation of the projected nuclear area were calculated from 200 nuclei in the smear. Our results indicate that morphometric estimation of mean nuclear size and/or degree of anisokaryosis is of no practical value in distinguishing between benign and malignant thyroid neoplasms of the oxyphilic type.     

Telomerase activity in thyroid fine needle aspirates

OBJECTIVE: To study the utility of telomerase activity (TA) detection in thyroid fine needle aspirates (FNAs). STUDY DESIGN: One hundred two thyroid nodules were studied: 70 in FNA samples and 32 in frozen tumors. From among FNA samples, there were 57 nodules of the goiter, 1 adenoma, 7 papillary carcinomas, 1 medullary carcinoma and 1 lymphoma. Three cases of thyroiditis were excluded. The 32 frozen tissue tumors consisted of 5 follicular adenomas, 4 follicular carcinomas and 23 papillary carcinomas. TA was analyzed by Telomerase PCR ELISA (Roche Diagnostics, Indianapolis, Indiana, U.S.A.). RESULTS: TA was negative in the 57 nonneoplastic nodules and 6 follicular adenomas and positive in 3 of 4 follicular carcinomas and 10 of 30 papillary carcinomas. TA sensitivity was 41.4% and specificity 100%. Sensitivity for malignancy was higher (85.7%) in FNAs than in TA. CONCLUSION: TA seems highly specific for neoplasms of the thyroid. Further studies are needed to confirm whether TA detection could contribute to identifying neoplasms when FNAs are inconclusive for malignancy and in cases of scanty material.     

Differentiation of Hashimoto's thyroiditis from thyroid neoplasms in fine needle aspirates

In order to refine the cytodiagnostic criteria for distinguishing Hashimoto's thyroiditis from thyroid neoplasms, aspirates from six cases of Hashimoto's thyroiditis, five Hürthle cell neoplasms and one papillary carcinoma associated with Hashimoto's thyroiditis were reevaluated. Distinguishing characteristics were cell arrangements, nuclear chromatin pattern and nucleolar appearance. Hashimoto's thyroiditis was characterized by flat sheets and clusters of epithelial cells with oncocytic changes or occasionally by cohesive tissue fragments with cells well oriented one to the other. Thyroid neoplasms were characterized by loosely cohesive, syncytial-type tissue fragments with crowded overlapping cells poorly oriented one to the other and/or numerous isolated single cells. The nuclear chromatin of Askanazy cells in Hashimoto's thyroiditis was bland and even while that of neoplastic cells was finely granular, coarsely granular or irregularly clumped. Macronucleoli were present in Hürthle cell tumors but not in the Askanazy cells of Hashimoto's thyroiditis. Epithelial cellularity, lymphoid cellularity, cellular polymorphism and nuclear pleomorphism were not useful criteria for making the differential diagnosis between the two conditions. An admixture of epithelial cells and lymphoid cells indicated Hashimoto's thyroiditis but was not helpful in ruling out an associated neoplasm.     

Grave's disease. Appearance in cytologic smears from fine needle aspirates of the thyroid gland

The cytomorphologic features were analyzed in thyroid samples obtained by fine needle aspiration (FNA) from 54 cases proven to be Grave's disease (toxic goiter) by a multiparameter study. A fire-flare appearance of the follicular cells and a good cellularity of the smears were the features most frequently observed in these cases. Hürthle cell changes were present in 47% of the cases, and small numbers of lymphocytes were seen in smears from 41% of the cases. Epithelioid cell granulomata and multinucleated giant cells were observed in less than one-fourth of the cases. About half of the cases showed some degree of pleomorphism of the follicular cells. Twenty cases of toxic multinodular goiter were similarly analyzed; the features that distinguished this entity from Grave's disease were the absence of epithelioid cells and multinucleated giant cells in the FNA smears.     

Tyrosine crystals in fine needle aspirates of a pleomorphic adenoma of the parotid gland

Tyrosine crystals were identified in the fine needle aspirate from a pleomorphic adenoma of the parotid gland. Such crystals have been seen before in tissue sections of pleomorphic adenomas, and they should be considered supportive evidence for a diagnosis of pleomorphic adenoma.     

Ringlike structures in fine needle aspirates from the breast

Spherical ringlike structures of various sizes resembling Liesegang rings (LRs) are described in four fine needle aspirates (FNAs) from breast lesions over a period of 13 years. A characteristic finding in these structures was a distinct double layer outer wall with striations and an amorphous central nidus. Under polarized light they were non-refractile and no birefringence was noted in Congo red. Immunohistochemical stains for calcium, iron, mucus, glycogen, amyloid, cytokeratin and epithelial membrane antigen in all the cases were found to be negative. Since LRs can be mistaken for ova or parasites, their presence in aspirates of breast should be kept in mind to avoid misdiagnosis.     

Microfilariae in fine needle aspirates from epididymal lesions

Microfilariae of Wuchereria bancrofti were observed in fine needle aspiration smears from three epididymal nodules, and degenerating microfilariae suggestive of Brugia malayi were found in the smears from a fourth case. The smears in all four cases showed a polymorphonuclear inflammatory cell component as well as epithelioid cell granulomata. While blood eosinophilia was present in all four cases, eosinophilia was present in the aspiration smears in only one case. Microfilariae could be demonstrated in the peripheral blood in only one case.     

MIB-1 immunohistometry of follicular adenoma and follicular carcinoma of the thyroid gland

OBJECTIVE: To analyze cellular proliferative activity, MIB-1 immunopositivity of normal tissue (n = 20), follicular adenoma (n = 30) and follicular carcinoma (n = 32) of the thyroid gland was analyzed by means of immunohistometry. STUDY DESIGN: Immunohistochemical reactions were performed on 3-micron sections from routinely formalin fixed and paraffin embedded surgical specimens using an indirect peroxidase method. The rate of immunostained cells was determined using the CM-2 TV image analysis system (Hund, Wetzlar, Federal Republic of Germany). Forty viewing fields (1.94 mm2) were measured with 20:1 objective magnification. An average of 5,965 cells were assessed in each case. RESULTS: Mean MIB-1 immunopositivity was higher in follicular carcinoma (average, 2.30%) and follicular adenoma (0.58%) than in normal thyroid tissue (0.14%). The distribution of single values differed significantly between groups (P < .001). To test the suitability of MIB-1 immunohistometry for the differential diagnosis of follicular adenoma and follicular carcinoma, different four-field tables with varying thresholds were calculated. Using a threshold of 0.9%, follicular carcinoma could be detected with a sensitivity of 75% (24/32) and a specificity of 83% (25/30). If a specificity of 90% is required (27/30), the sensitivity of the test decreases to 69% (22/32), based on a threshold of 1.1%. CONCLUSION: As some overlap of single values has to be considered, MIB-1 immunohistometry, although presenting new insights into the proliferative potential of thyroid lesions, is of only limited value for the differential diagnosis of follicular lesions in routine surgical pathology.     

Fine needle aspirates of follicular lesions of the thyroid gland. The intermediate-type smear

In order to evaluate fine needle aspirates of thyroid lesions with features intermediate between those of follicular neoplasms and colloid nodules, 38 aspirates in which a definitive diagnosis had not been made were reviewed. On review, ten aspirates were excluded from the "intermediate" category; seven were reclassified as unsatisfactory and one as a cellular colloid nodule. Two papillary carcinomas showed a complex pattern not identified in smears from other lesions; these aspirates were also classified separately for independent evaluation. The remaining 28 aspirates were characterized by syncytial-type tissue fragments with mild nuclear atypia. The association of syncytial-type tissue fragments and orderly sheets and fragments forming a honeycomb pattern in the same aspirate indicated a colloid nodule, though a two-disease process could not be excluded. Of the aspirates containing only syncytial-type tissue fragments, 50% were from adenomas, 25% were from carcinomas, and 25% were from colloid nodules. Criteria to distinguish between the various follicular lesions were not identified in these smears.     

Signet-ring follicular adenoma of the thyroid diagnosed by fine needle aspiration. Report of a case with cytologic description

BACKGROUND: Follicular cells of the thyroid may undergo squamous, oncocytic or clear cell metaplastic changes. Of these, the clear cell change with signet-ring formation is the most unusual, and follicular adenoma of the thyroid with signet-ring formation is extremely rare. We describe for the first time the cytologic features of a clear cell adenoma of the thyroid obtained by fine needle aspiration (FNA). CASE: A 48-year-old woman in a euthyroid state presented with a 2-cm, right-sided thyroid nodule. Smears obtained by FNA of the nodule revealed clusters of large signet-ring cells in a bloody background. The signet-ring cells were round to oval, with large cytoplasmic vacuoles and hyperchromatic, eccentric nuclei. Colloid in the background was very scanty. Histologic examination of the right hemithyroidectomy specimen revealed a signet-ring follicular adenoma. CONCLUSION: Lack of familiarity with signet-ring cell adenoma of the thyroid could lead to an erroneous diagnosis of metastatic signet-ring cell carcinoma.     

Morphometric analysis of fine needle aspirates from breast lesions

In an attempt to discover the morphometric variables with the most diagnostic power in the differentiation of benign from malignant breast disease, 20 unequivocally benign and 20 unequivocally malignant and histologically confirmed breast aspirates were examined on an image analyser. It was found that standard deviation of nuclear area was the most discriminant variable. Then 23 aspirates initially diagnosed as 'suspicious of malignancy' were measured by the same technique, and standard deviation of nuclear area correctly differentiated all but three cases.