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M Sobrinho-Simóes

Publications and source records attributed to M Sobrinho-Simóes.

3 recordsLinked to original sources

Ultrastructural morphometry of thyroid neoplasms.

This paper presents the first comprehensive morphometry analysis of normal thyroid, adenomas, and follicular and papillary carcinomas. The mean nuclear volume and the mean nuclear surface increased, while the volume densities of rough endoplasmic reticulum and dense bodies decreased from normal thyroid through adenomas and follicular carcinomas to papillary carcinomas. The different amounts of cytoplasmic organelles probably are related to endocrine function rather than to malignant potential. Papillary carcinomas with a predominantly follicular growth pattern are related more closely to follicular carcinomas than to papillary carcinomas dominated by papillae. This probably indicates a more active endocrine function rather than a different degree of malignancy. Papillary carcinomas, where follicular structures dominate, are therefore expected to respond to radioiodine treatment more favorably than those mainly forming papillae. Papillary carcinomas with abundant ground glass nuclei do not seem to have a lower volume density of heterochromatin than tumors lacking this nuclear feature. In the individual problem case with a follicular tumor, electron microscopy and morphometry cannot even distinguish between an adenoma and a well-differentiated follicular carcinoma.

Adenocarcinoma↗

A flow cytometric DNA analysis of medullary thyroid carcinoma.

Flow cytometric DNA analysis of biopsy specimens from 10 patients with medullary carcinoma of the thyroid (MCT) was performed to evaluate the possible value of such data as indicators of the biologic behavior of these tumors. Some of the tumors had a unimodal distribution of nuclear DNA content, whereas others were bimodal. The mean modal DNA content in the cells of unimodal medullary carcinomas was not higher than that in the cells of thyroid parenchyma with a normal histologic appearance. This finding contradicts previous reports based on conventional cytophotometry. Bimodal DNA histograms were found in biopsy specimens from four patients, and the two patients with predominantly spindle-shaped cells belonged to this group. The total of nine biopsy specimens with bimodal DNA distributions were all from metastatic foci. Bimodal patterns were found, however, to co-exist with unimodal patterns, when several samples were examined from the same case. Bimodality or more severe aneuploidy did not seem to be related to shorter survival of the patients. The mean value of the percentage of cells in S-phase in our MCT series was higher than in follicular but lower than in anaplastic carcinomas. This fits well with clinical studies, where medullary carcinoma patients have been found to live longer than patients with follicular carcinomas but for a shorter time than those having anaplastic carcinomas.

Adult↗