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M Sobrinho-Simões

Publications and source records attributed to M Sobrinho-Simões.

At least 127 records · Page 7Linked to original sources
PubMed1986

Lectin histochemistry of papillary and follicular carcinoma of the thyroid gland.

The lectin-binding properties of human follicular and papillary carcinoma were studied histochemically and compared with lectin binding to normal or goitrous thyroid tissue. Well-differentiated minimally invasive follicular carcinoma showed a lectin-binding pattern essentially identical to those of the normal thyroid gland and benign adenomatous lesions. Overtly invasive follicular carcinoma showed focal reactivity with some lectins that were nonreactive with normal follicular thyroid cells (Solanum tuberosum and soybean in three of three cases; Ulex europaeus in two of three cases; and Dolichos biflorus, Laburnum alpinum, and peanut in one of three cases). In papillary carcinomas, the cells lining the papillary structures reacted focally with some lectins that did not bind to normal thyroid cells (S tuberosum and U europeaus in seven of seven cases; Helix pomatia, Helix aspersa, and soybean in four of seven cases; and peanut, Griffonia simplicifolia, D biflorus, and Vicia villosa in one of seven cases). All these lectins, as well as those reacting with normal thyroid cells, reacted more strongly with cells of papillary structures than with those forming solid nests and follicles. Despite these lectin-defined differences in the composition of glycoconjugates of benign and malignant thyroid cells, the inconsistent and focal nature of the changes precludes the use of lectins in diagnostic histopathology.

Adenocarcinoma↗
PubMed1985

Medullary carcinoma of the thyroid gland: an immunocytochemical study.

Twenty-seven cases of medullary carcinoma of the thyroid gland (MCT) were studied by light microscopy, immunocytochemistry, and electron microscopy. Immunoreactivity for neuron-specific enolase (NSE) and calcitonin was present in all tumors. The numbers of peptides and serotonin demonstrated in each case varied from one to eight. Bombesin was present in 18 of the 27 cases, serotonin in 15, leu-enkephalin in 8, somatostatin in 8, gastrin in 3, substance P in 1, vasoactive intestinal peptide (VIP) in 1, and ACTH in 1. Insulin and glucagon were not encountered in any of the tumors. Immunoreactivity for thyroglobulin was seen in five primary tumors as well as in one lymph node metastasis. The finding of concurrent production of calcitonin and thyroglobulin within the same tumor is enough to question the dogma of the separate origin of follicular cells and C-cells. We were unable to attach any clinical importance to the production of multiple peptides and/or amines.

Adolescent↗
PubMed1985

Lymphoid hypophysitis in a patient with lymphoid thyroiditis, lymphoid adrenalitis, and idiopathic retroperitoneal fibrosis.

We describe the autopsy findings in a 24-year-old woman with a clinical picture of pituitary and adrenal insufficiency which had its onset shortly after a normal pregnancy and delivery of a normal infant, two years before the mother's death. There were heavy lymphocytic infiltrations of the adenohypophysis, thyroid, and adrenals as well as diffuse retroperitoneal fibrosis with numerous perivascular lymphocytic infiltrates. It is concluded that lymphoid hypophysitis probably represents the hypophyseal counterpart of other endocrine autoimmune disorders and that immune mechanisms may also play a role in the pathogenesis of the so-called idiopathic retroperitoneal fibrosis.

Adrenal Glands↗
PubMed1983

Hodgkin's disease with predominant infradiaphragmatic involvement and massive invasion of the bone marrow. A necropsic study of nine cases.

The authors report the results obtained in the necropsic study of nine cases of the so-called acute, visceral form of Hodgkin's disease (HD). Most of the patients (six men and three women, ranging from 42 to 74 years of age) lacked peripheral lymphadenopathies and had fever, weight loss, abnormality of hepatic function, and pancytopenia. Mixed cellularity was diagnosed in two, diffuse fibrosis in four, and reticular subtype of lymphocyte depletion in three cases. Despite the predominant infradiaphragmatic involvement, supradiaphragmatic lymph nodes were involved in six and tonsils in three cases. Spleen and bone marrow were involved in eight cases and the liver was involved in seven cases. In four cases there were also lesions in other extralymphoid organs. The involvement of the bone marrow was widespread and showed concurrent myelofibrosis and/or other signs of hematopoietic disturbance. There was a close relationship between the presence of vascular invasion (seven cases) and the extent of HD spread. It is concluded that despite its peculiarity, this form of HD fits the classic model of unicentric origin, lymphogenic contiguous spread, and hematogeneous dissemination, and should not be identified with any particular histologic type of HD.

Adult↗
PubMed1982

Papillary carcinomas of the thyroid have pore-deficient nuclei.

A significant reduction in nuclear pore density observed in papillary carcinomas compared to normal thyroid, adenomas and follicular carcinomas probably disturbs the nucleo-cytoplasmic transfer of ribonucleoproteins. This may contribute to the slow growth and indolent biological behavior of these tumors where even the presence of regional lymph node metastases does not worsen the prognosis. The signs of nuclear hyperactivity may result from an attempt to compensate for the nuclear membrane defect.

Adenocarcinoma↗
PubMed1982

The diagnostic value of flow cytometric DNA measurements in selected disorders of the human thyroid.

A flow cytometric (FCM) analysis of biopsies from 19 patients with thyroid lesions (Hashimoto's thyroiditis, hyperplastic goiter, colloid and adenomatous nodular goiter, follicular adenoma, follicular carcinoma, anaplastic carcinoma) was performed to evaluate the relevance of such results for the individual diagnosis and prognosis and prognosis of such diseases. All cases of Hashimoto's thyroiditis, the colloid nodular goiters, and the hyperplastic goiter had a unimodal diploid pattern, while the anaplastic carcinomas were aneuploid. These lesions are, however, easily diagnosed on morphological grounds and their FCM classification would only be redundant. Follicular adenomas and follicular carcinomas may be either unimodal diploid or aneuploid, and our single case of adenomatous colloid goiter showed a bimodal DNA distribution. This means that a diploid modal DNA content in a follicular tumor does not rule out malignancy, while aneuploidy is not an unequivocal sign on malignancy. The evaluation of the percentage of cells in S-phase did not seem to contribute valuable information for the individual diagnosis of malignancy within the group of thyroid lesions studied. Our study indicates a rather limited clinical value of FCM measurements of DNA in the individual case of thyroid disease.

Adolescent↗
PubMed1982

The fine structure of follicular thyroid adenomas.

Twenty-five adenomas of the thyroid were studied by transmission and scanning electron microscopy: 14 embryonal, fetal, and simple adenomas, 1 colloid adenoma, 2 toxic adenomas, 2 oxyphil adenomas, 2 "atypical adenomas" and 4 adenomas with capsular invasion, formerly designated "malignant adenomas." The only adenomas that presented with special ultrastructural features were the oxyphil and the toxic varieties. The toxic adenomas had organelle-rich cells with numerous and long microvilli on their surfaces. The oxyphil adenomas showed Hürthle cell changes, including abundant mitochondria, and smooth cell surfaces. The subdivision of the other forms of adenomas was impossible at the ultrastructural level; and this study did not reveal ultrastructural features which could distinguish the so-called "atypical" and "malignant" adenomas from ordinary thyroid adenomas. "Malignant" adenomas should preferable be called what they are: adenomas with capsular invasion. Neither does this study support the view that electron microscopy is a useful method to separate an adenoma from a well-differentiated follicular carcinoma in the occasional patient who presents problems.

Adenocarcinoma↗
PubMed1982

Surface features in human thyroid disorders. A scanning electron microscopic study of ninety five cases.

The surface features of nodular goitre, follicular adenomas, focal and Hashimoto type thyroiditis, Graves' disease, follicular carcinomas, papillary carcinomas, anaplastic carcinomas, medullary carcinomas and malignant lymphomas are presented in this scanning electron microscopic study of 95 cases. Scanning electron microscopy was found to be an excellent method for studying the surface topography of the diseased cells at high magnification and with a great depth of field. However, scanning electron microscopy does not seem to be a valuable tool for the diagnostic and prognostic routine evaluation of thyroid disorders.

Adenoma↗
PubMed1981

A flow cytometric deoxyribonucleic acid analysis of papillary thyroid carcinoma.

We present the first comprehensive flow cytometric analysis of papillary carcinoma of the human thyroid. All but one of the 22 papillary carcinomas showed a unimodal distribution of the nuclear DNA content. The mean modal DNA was significantly lower in papillary carcinomas than in normal thyroid tissue, a finding which is contradictory to some earlier reports based on conventional cytophotometry. Tumors predominantly composed of Hürthle cells had a significantly higher mean modal DNA, whereas no significant difference was found between tumors with many ground glass nuclei and those lacking this nuclear feature. A very low percentage of S-phase cells was found both in the primary tumors and their metastases. This percentage was even lower than in normal thyroid tissue. The low proliferative activity may in part explain why most papillary thyroid carcinomas run such a surprisingly indolent course even after the establishment of regional lymph node metastases.

Adult↗
PubMed1981

Scanning electron microscopy of the normal human thyroid.

We have studied normal thyroid specimens from 20 euthyroid patients with the scanning electron microscope. A significant negative correlation was found between the diameter of the apical cell surface and the density of microvilli. Large follicles were usually surrounded by smooth-surfaced cells with a large apical diameter, while the smaller follicles were surrounded by smaller cells with numerous and large microvilli. Exceptions to this rule were, however, not uncommon, and the morphological differences between neighbouring cells in one and the same follicle were as great as those between the cells of different follicles. Concurrent transmission electron microscopy showed that the morphology of the apical cell membrane reflects the activity of the follicular cells. The scanning electron microscopical findings thus indicate that the thyroid may have an intrafollicular functional cycle as important or more important than an interfollicular cycle. Our study shows that one to five cilia are regular constituents of the normal follicular cells and that their number is not correlated with the diameter of the apical cell surface nor with the density of microvilli. Although we do not rule out the possibility that they may be fetal rudiments, we suggest that they may play a functional role probably by stirring the colloid.

Adult↗
PubMed1980

The origin and significance of thyroid psammoma bodies.

We have used ultrastructural techniques to study the pathogenesis of calcifications and psammoma bodies in human thyroid disorders. Particular attention was paid to psammoma bodies associated with papillary thyroid carcinoma which were found to represent the end stages of two different biologic events. The one event took place in the vascular stalk of the neoplastic papillae, starting with a thickening of the base lamina followed by a vascular thrombosis, calcification, and tumor cell necrosis. In the other, intralymphatic tumor thrombi in the thyroid adjacent to the main tumors or in the opposite thyroid lobe became necrotic and calcified. In some instances, destruction of the lymphy vessels led to fibrin exudation and perilymphatic fibrosis. The laminated bodies seen inside thyroid follicles in some nonneoplastic conditions were found to represent inspissated colloid and not considered to be true psammoma bodies. Like the amyloid calcifications seen in medullary carcinoma and the stromal calcospherites seen in several conditions, they seem to lack diagnostic importance. Our findings emphasize the biologic importance of the events leading to psammoma body formation and explain how they may contribute to the indolent course of this type of cancer.

Carcinoma↗
PubMed1980

Endocrine cell carcinoma of the uterine cervix.

We present an endocrine cell carcinoma of the uterine cervix in a 21-year-old woman which we studied by histochemical, immunocytochemical, and ultrastructural methods. The tumor had a histologic appearance similar to an oat cell carcinoma, and carcinoma in situ changes were found in the adjacent cervical surface epithelium. Histochemistry and electron microscopy revealed argyrophil cells containing small round secretory granules; more rarely argentaffin (enterochromaffin) cells were seen with dense, elongated and pleomorphic granules and numerous undifferentiated cells with few and small granules. Our findings indicate that the different types of endocrine tumor cells have the same stem cell origin and necessitate the revision of some of the concepts of the embryogenesis of the APUD cells and their tumors. We emphasize that all undifferentiated or poorly differentiated carcinomas of the uterine cervix should be examined histochemically and ultrastructurally, particularly since their correct classification has prognostic and therapeutic implications.

Adult↗