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A Ryska

Publications and source records attributed to A Ryska.

53 records · Page 3Linked to original sources
PubMed1999

Sensitivity and specificity of the fine needle aspiration biopsy of the thyroid: clinical point of view.

INTRODUCTION: The rates of sensitivity and specificity of fine needle aspiration biopsy (FNAB) for the diagnosis of thyroid malignancy differ considerably among various reported series. These values are influenced by three factors: (a) whether only clearly positive and negative results are considered, or whether the commonly encountered 10-20% of indeterminate/suspicious ones are included; (b) whether adenomas are considered as neoplasms in one group with carcinomas; and (c) whether only histologically proven cases are used in calculations or whether patients with benign clinical follow-up are included. AIM: The aim of the study was to evaluate the sensitivity and specificity of FNABs performed at this institution in the last 7 years from the clinical point of view, considering only benign vs. suspicious/malignant FNAB results (indicating surgery), and benign (including adenomas) vs. malignant definitive histology. STUDY DESIGN: Retrospective study comparing pre-operative FNAB results with definitive histological examination after operation. PATIENTS: A total of 2492 FNABs were performed in 2100 patients (1875 women and 225 men); their ages ranged from 9 to 85 years, with a median of 46 years. Clinical diagnosis was multinodular goitre in 1330, single nodule in 591, Hashimoto's thyroiditis in 147 and subacute thyroiditis in 32 cases. In 148 instances, the nodule was cystic. A history of previous treatment for carcinoma of the thyroid was present in 12 patients. Five hundred and thirty-six patients subsequently underwent thyroid surgery. STATISTICS: The values of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were calculated. RESULTS: The sensitivity was 86%, specificity 74%, PPV 34%, NPV 97% and diagnostic accuracy 75%. CONCLUSIONS: The specificity and positive predictive value are low when fine needle aspiration biopsy results are divided into two categories only (these being indication for surgery or not), and when only suspicious/malignant fine needle aspiration biopsies with subsequent malignant histology are considered to be true positive. Nevertheless, the ability to discriminate 11.7% of patients with a 34% probability of malignancy (suspicious/malignant cytology) from 81.2% of patients (benign cytology) with a probability of only 3% is very helpful.

Adenoma↗
PubMed1999

[Malignant branchiogenic cyst--fact or fiction?].

A case of a cystic metastasis of squamous cell carcinoma of palatine tonsil in a 54-year-old male is reported, clinically presenting as a branchiogenic cyst. The grade of differentiation of the squamous cell epithelium lining the cyst was very variable: in some areas it was extremely well differentiated, thus resembling common benign branchial cleft cyst; transition to dysplastic areas with features of carcinoma in situ was visible and finally, in one small focus, invasion of the epithelial structures into the lymphoid tissue was observed. Despite its metastatic nature, the tumor fulfilled histological criteria of a so called malignant branchiogenic cyst (branchiogenic carcinoma). The authors discuss the existence of primary malignant branchiogenic cyst and the criteria necessary for its diagnosis.

Bronchogenic Cyst↗
PubMed1999

[Malignant myoepithelioma of the parotid gland: cytologic and histologic features].

A case of malignant myoepithelioma of the parotid gland in a 34-year-old female is presented. In the fine-needle aspiration material, there was predominance of poorly cohesive polygonal cells with marked nuclear pleomorphism; no mitotic figures were observed. Focally, fragments of myxoid metachromatic intercellular material were also present. Histologically, the tumor was encepsulated, showing focal invasion of the capsule and tumor thrombi in the capsular vessels. The tumor was predominantly solid and myxoid, composed of cells with epithelioid features, marked anisonucleosis and a low mitotic activity. Immunohistochemically, the cells revealed positive staining for S-100 protein, vimentin, cytokeratins, glial acidic fibrillary protein and carcinoembryonic antigen; only several cell groups expressed smooth muscle actin and desmin; muscle specific actin was uniformly negative. In differential diagnosis, it was important to distinguish malignant myoepitelioma mainly from pleomorphic adenoma (mixed tumor), benign myoepithelioma, carcinoma ex pleomorphic adenoma and malignant melanoma. The criteria of malignancy in myoepithelial tumors are discussed.

Adult↗
PubMed1998

Epithelial-myoepithelial carcinoma of the bronchus.

An extremely rare case of epithelial-myoepithelial carcinoma (EMC) of a lobar bronchus in a 47-year-old female is reported. Grossly, the tumor formed a polypoid mass obstructing the bronchial lumen. Microscopically, it was composed of two cellular types--epithelial cells with eosinophilic cytoplasm and clear myoepithelial cells. Numerous tubules formed by an inner epithelial and outer myoepithelial layer were found. Focally, the tumor showed solid growth of clear cells. Prominent hyalinization of the stroma was found. The nature of the cells was confirmed by positive expression of cytokeratins and epithelial membrane antigen in epithelial cells and vimentin and smooth muscle actin in myoepithelial cells. Differential diagnosis of EMC includes a broad spectrum of salivary gland-type tumors. Furthermore, metastases of clear cell carcinoma of the kidney or thyroid, clear cell ("sugar") tumor of the lung, glandular form of carcinoid, bronchioalveolar adenocarcinoma with myoepithelial cells and pulmonary adenosquamous carcinoma with amyloid-like stroma must be distinguished from EMC. The tumor has neither recurred nor metastasised, a fact supporting the current opinion, that EMC is a tumor of low grade malignancy.

Actins↗
PubMed1998

[Synovial metaplasia around breast implants].

Three cases of the periprosthetic breast capsules showing typical features of synovial metaplasia are presented. The histological picture is characterized by the presence of cellular layer mimicking synovial membrane. These elements are devoid of basement membrane, otherwise, nevertheless, they strongly resemble single- or multilayered epithelium. Focally, the differentiation towards giant multinucleated cells is noted. Immunohistochemical profile, as well as the ultrastructure of the cells, confirms their histiocytic origin with advanced differentiation towards elements of the synovial membrane. These histological features are referred to as synovial or synovial-like metaplasia. They are found in considerable fraction of textured breast implant capsules. The pathogenesis remains uncertain; however, similar picture was observed in other locations in association with prolonged or repeated action of mechanical forces. Thus, movement of the implant in situ is the most probable trigger of synovial metaplasia.

Adult↗
PubMed1998

[Pathology on the Internet].

Authors' experience gained during a one year usage of the Internet is presented. By now we have found many useful information resources related to the field of pathology. The MEDLINE database is available free of charge at several web sites as well as teaching diagnostic seminars, electronic color atlases, medical publishers homepages, etc. There is also a possibility to enter various topic-related groups in the framework of Internet discussion groups. The limiting factors for reaching medical information from the Internet is hardware and software equipment, the cost of Internet connection, and the data transmission capacity of phone lines.

Computer Communication Networks↗
PubMed1998

[Pseudoangiomatous hyperplasia of mammary stroma].

Four cases of pseudoangiomatous hyperplasia of mammary stroma (PAH) were described (3 women and 1 man aged 15 to 42 years). Clinically in women, they presented as firm, nontender, movable nodules, 1 to 4 cm in diameter, diagnosed clinically usually as fibroadenoma. In the male patient, the lesion was tender, resembling gynecomastia. Microscopically, they were characterized by the presence of anastomosing, empty-looking, slit-shaped spaces irregularly lined by the spindle cells with small, uniformly ovoid nuclei, dispersed throughout the mammary stroma. Immunohistochemically, these cells were vimentin positive, factor VIII and CD31 negative. They did not express estrogen receptor, in one case there was a weak progesteron receptor positivity. Ultrastructurally, the lining cells were of a fibroblastic character. The pathogenesis of PAH is unclear, presumed to be of reactive nature by the authors, probably as an exuberant reaction of stromal cells to hormonal stimuli. In differential diagnosis, PAH should be distinguished from low-grade angiosarcoma, as well as from perilobular hemangioma, diffuse angiomatosis and vascular anomalies.

Adolescent↗
PubMed1997

Well-differentiated acinic cell carcinoma of salivary glands associated with lymphoid stroma.

In a multicenter study, 69 acinic cell carcinomas of the salivary glands were identified, of which 12 constituted what the authors believe to be a distinct subgroup. Their most noticeable feature was a dense lymphoid stroma with well-developed germinal centers, surrounding a sometimes scanty epithelial component, which in each case had a microcystic growth pattern. All these tumors were enveloped by a thin fibrous pseudocapsule, thus mimicking an intraparotid lymph node containing a metastasis. All 12 cases showed low MIB1 proliferative activity, with a mean index of 1.7% (range, 0.5 to 3.7). All patients remained well without recurrence or metastasis in followup periods of 19 months to 14 years. A second subgroup of nine acinic cell carcinomas also possessed a heavy lymphoid stroma with germinal centers, but its distribution was more patchy than in the first subgroup, and in addition, the fibrous pseudo-capsule was incomplete or absent. In each case the epithelial growth pattern was other than microcystic. These tumors had significantly higher MIB1 indices (mean, 17%; range, 3.4 to 45). In contrast to the first subgroup, only three of nine patients remained well with no further disease. The other six patients developed recurrences or metastases, and two died of disseminated cancer. In view of the clinical and pathological data, it is speculated that the tumor foci lacking lymphoid stroma in each of the second subgroup possibly represented a clone of high-grade malignancy arising within a low-grade acinic cell carcinoma with lymphoid stroma.

Adult↗
PubMed1997

Intrathyroidal lymphoepithelial cyst. A report of two cases not associated with Hashimoto's thyroiditis.

Two cases of intrathyroidal lymphoepithelial cyst are described. Both of them were solitary, one being found incidentally in a patient operated on for a multinodular goiter, the other being clinically obvious as a cold nodule. They exhibited features of cysts of branchial cleft origin, i.e. squamous cell lining epithelium and abundant lymphoid tissue with reactive germinal centers. The thyroid gland parenchyma showed a discrete lymphoid infiltration consistent with the diagnosis of focal lymphocytic thyroiditis. In the first case a single epidermoid solid cell nest was found. The histogenesis of intrathyroidal lymphoepithelial cysts remains unclear, but their origin from cystically degenerated ultimobranchial body remnants (solid cell nests) seems to be most probable. This assumption is supported by a similar immunohistochemical profile of solid cell nests and epithelial cells lining the cysts and also by the presence of one solid cell nest in the proximity to the cyst in one of our cases.

Adult↗
PubMed1997

Giant cell epulis with unusual clinical and radiological features--a diagnostic pitfall in FNAC material. Report of a case with differential diagnosis.

Giant cell epulis (peripheral giant cell granuloma) is a tumorlike condition of the gingiva found predominantly in elderly women. A case of peripheral giant cell granuloma of the mandibular gingiva, examined by fine needle aspiration biopsy, is herein reported. A 51-year-old woman presented with a three week history of bleeding from a six cm tumor located in the central part of the mandible. On radiography, an osteolytic lesion was present, suspicious of malignancy. An aspiration biopsy revealed microscopic features suggesting the diagnosis of a giant cell lesion of possibly malignant nature. Surgical resection was performed. Histological examination showed giant cell epulis destroying the mandibular bone. Differential diagnosis of this lesion is widely discussed.

Biopsy, Needle↗
PubMed1997

[Calciphylaxis in a patient on long-term dialysis].

Calciphylaxis is a special form of soft tissue calcification (in particular blood vessels), affecting specially patients with chronic renal insufficiency and associated secondary hyperparathyroidism. Most severely affected are small arteries with a diameter of 0.2-0.5 mm at the interface of the corium and subcutaneous layer. Calcification of the vascular media with subsequent narrowing of the lumen causes ischaemic changes manifested by the development of painful reddish-violet spots on the skin with necrosis and ulcerations. The authors describe the case of a 73-year-old diabetic female patient with regular dialyzation treatment. The patient developed reddish-violet spots on the lower extremities shortly before admission to hospital. At the site of the spots rapidly progressing necroses developed. The cause of these ischaemic changes were calciphylactic changes confirmed on post-mortem examination and by histological examination.

Aged↗
PubMed1996

[Differentiating parathyroid adenoma from microfollicular thyroid nodule in fine-needle aspiration cytology].

Two cases of fine needle aspiration cytology of parathyroid adenoma were not misinterpreted as microfollicular nodules of the thyroid. Discrimination of those two lesion is a diagnostic pitfall in cytological material. Authors pointed out criteria for differential diagnosis. Radioimmunoanalysis of parathormone in aspirate served as a simple, safe and reliable method in these cases.

Adenoma↗
PubMedDate not supplied

Diagnostic role of markers dipeptidyl peptidase IV and thyroid peroxidase in thyroid tumors.

BACKGROUND: In seeking to improve the differential diagnosis between malignant and benign thyroid tumors of follicular cell origin, we assessed the expression of dipeptidyl peptidase IV (DPP IV) and thyroid peroxidase (TPO). DPP IV is a membrane peptidase expressed in many human tissues, excluding the normal thyroid gland. However, aberrant expression has been described in thyroid carcinomas. TPO is an essential enzyme in the biosynthesis of thyroid hormones with various types of expression in pathological thyroid lesions. MATERIALS AND METHODS: A total of 151 thyroid glands were examined: 24 malignant tumors, 29 benign tumors, 98 benign lesions and 5 normal glands. DPP IV expression was analyzed by a histochemical technique in both frozen sections and imprint/aspirate smears. TPO was assessed immunohistochemically in paraffin-embedded specimens. RESULTS: DPP IV sensitivity in frozen section was 56% and its specificity was 99%, in both cases with a 50% threshold. In cytology, the sensitivity was 68% and the specificity was 98% using the 50% threshold. TPO sensitivity and specificity was 64% and 99%, respectively. The sensitivity and specificity of both markers was 92% and 94%, respectively. CONCLUSION: We recommend adding DPP IV and TPO to the list of diagnostic tumor markers for malignant thyroid tumors of follicular cell origin.

Adenoma↗
PubMedDate not supplied

TPS, thymidine kinase, VEGF and endostatin in cytosol of thyroid tissue samples.

The aim of the study was to determine whether VEGF, TPS, TK or Endostatin determination in tissue cytosol may have some additional value in distinguishing among different types of thyroid lesions. These markers were chosen as representatives of the 2 main pathways (angiogenesis and proliferation) involved in thyroid diseases. VEGF is the most potent angiogenic promoter and Endostatin plays an opposing role. Thymidine kinase (TK) is a marker of DNA synthesis and TPS, cytokeratin 18 fragments, is a marker of the rate of proliferation. We determined qualitatively all four markers in tissue extracts: cytosol from 157 tissue specimens (93 goitre, 12 Hashimoto's thyroiditis, 39 adenomas and 13 carcinomas). In 6 cases we were able to compare both normal and pathological tissue samples from a single patient. Statistically significant differences were found in the measured markers, but outliers were present in all groups. This fact does not permit their use in differential diagnosis. The highest levels of all markers were reached in adenomas, being higher than in carcinomas, probably explained by the higher overall metabolic rate in adenomas.

Cytosol↗
PubMedDate not supplied

Proliferative markers in diagnosis of thyroid tumors: a comparative study of MIB-1 and topoisomerase II-a immunostaining.

BACKGROUND: The differential diagnosis of well-differentiated tumors of follicular cell origin remains a most problematic task in thyroid pathology. Therefore, various diagnostic/prognostic thyroid markers are currently being studied. The aim of our study was to evaluate the proliferative MIB-1 and topoisomerase II-alpha markers in both oncocytic and non-oncocytic epithelial thyroid tumors. MATERIALS AND METHODS: Proliferative activity was analyzed by means of immunohistochemistry in 215 thyroid tumors and the evaluated proliferative indices (PI) were correlated with morphological diagnosis. Comparison of both proliferative markers was made. The results were statistically analyzed using Wilcoxon tests (significance level p<0.05) and the Spearman correlation coefficient. RESULTS: Carcinomas generally showed significantly higher PI than adenomas, irrespective of their oncocytic or non-oncocytic features. Moreover, PI in oncocytic adenomas was significantly higher than in non-oncocytic ones. However, PI in both oncocytic and non-oncocytic carcinomas, including papillary microcarcinomas, were similar. The studied proliferative markers correlated with each other. CONCLUSION: PI can help the differential diagnosis of morphologically difficult cases of thyroid tumors. Oncocytic adenomas have higher malignant potential and should be promptly surgically removed. Both MIB-1 and topoisomerase II-alpha are recommended for the evaluation of thyroid tumor cell proliferation.

Antigens, Neoplasm↗