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M Sobrinho-Simões

Publications and source records attributed to M Sobrinho-Simões.

142 records · Page 8Linked to original sources
PubMedDate not supplied

Cytologic features of fine needle aspirates of papillary and mucoepidermoid carcinoma of the thyroid with anaplastic transformation. A case report.

BACKGROUND: Papillary carcinoma is the most common type of thyroid cancer. Cases of papillary carcinoma merging with squamous carcinoma, mucoepidermoid carcinoma, insular carcinoma, columnar cell carcinoma, poorly differentiated carcinoma, anaplastic carcinoma and medullary carcinoma have been reported to date. CASE: A 62-year-old female presented with a 3-cm, hard and painful tumor in the right lobe of the thyroid gland. Fine needle aspiration biopsy yielded a diagnosis of undifferentiated (anaplastic) carcinoma. The tumor was deemed a papillary and mucoepidermoid carcinoma of the thyroid with anaplastic transformation on histology. On retrospective review, the aspirates showed cytologic features of papillary, mucoepidermoid and anaplastic carcinoma. Cellular sheets showing a combination of squamous and mucin-producing features and microcystic like pattern containing hyaline bodies and/or amorphous material correlated well with the histologic and ultrastructural features of mucoepidermoid carcinoma. To our knowledge, no other case with these cytologic characteristics has been reported previously. CONCLUSION: This case illustrates that fine needle aspiration biopsy can be used to recognize rare malignant thyroid neoplasms showing a combination of papillary, mucoepidermoid and undifferentiated carcinoma.

Biopsy, Needle↗
PubMedDate not supplied

Signet ring cell carcinoma of the stomach: a morphometric, ultrastructural, and DNA cytometric study.

The present study was undertaken to determine whether or not signet ring cell (diffuse, isolated cell) gastric carcinomas display a specific profile at the ultrastructural, morphometric, and DNA cytometric levels. Thirty-two cases of gastric carcinoma and 8 cases of peptic ulcer (control group) were studied with electron microscopy, morphometry, flow cytometry, and image cytometry. Despite the ultrastructural cellular heterogeneity of signet ring cell carcinomas, the neoplastic cells display fairly constant morphometric features: The cellular and nuclear volumes are significantly smaller than those of the other types of gastric carcinomas and closely resemble those of normal foveolar cells. The relatively small size of signet ring cell carcinoma nuclei fits with the high percentage of the cases of this type of gastric carcinoma that are either diploid or nearly diploid. There is a relationship between the infiltrative pattern of growth of gastric carcinoma (regardless of histologic subtype and ultrastructural cell differentiation) and the small size of neoplastic cells and their nuclei.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

Proliferative activity of synovial sarcoma: an immunohistochemical evaluation of Ki-67 labeling indices of 52 primary and recurrent tumors.

The relationship between cell differentiation and proliferation in biphasic synovial sarcoma (BSS) and the connection between the two components of these tumors and monophasic synovial sarcoma (MSS) are still unknown. In this study we specifically compared the Ki-67 labeling indices (Ki-67-LI) in the solid/glandular and spindle cell components of primary BSS (n = 8) as well as the values thus obtained in primary BSS both outside clear-cut biphasic areas (n = 7) and in primary MSS (n = 23). We also compare the Ki-67-LI of primary tumors (seven BSS, seven MSS) and their respective first recurrences. We observed that the cells of the solid/glandular component of BSS proliferate significantly faster (p = 0.007) than those of spindle cell areas. No significantly different Ki-67-LI were observed in the comparison of the solid/glandular areas of BSS with the spindle/epithelioid component of BSS without clear-cut biphasia and MSS. No significant differences of Ki-67-LI were observed in the comparison of primary tumors of both subtypes with their respective first recurrences. The implications of the low proliferative activity of the spindle cell component of BSS exhibiting clear-cut biphasia, which was also confirmed in a concurrent study using anti-proliferating cell nuclear antigen/Cyclin PC10, remains to be clarified.

Adolescent↗
PubMedDate not supplied

Follicular carcinoma of the human thyroid gland: an ultrastructural study with emphasis on scanning electron microscopy.

Previous ultrastructural studies on follicular thyroid carcinomas present conflicting results, in particular with regard to the surface features of the neoplastic cells. The present study of 9 cases with varying degrees of differentiation is the first comprehensive investigation by concurrent transmission and scanning electron microscopy. In the well-differentiated tumours we found a slightly increased number of microvilli and a decreased number of cilia per cell as compared to the normal thyroid follicles, while moderately differentiated tumours had a smaller number of microvilli and no cilia. The cells in anaplastic foci had unimpressive surfaces with only scattered clusters of short microvilli. Neither scanning nor transmission electron microscopy seem to be of major importance in the diagnostic evaluation of the individual case of follicular thyroid carcinoma or in the assessment of prognosis. Scanning electron microscopy presents a wealth of information on the three dimensional surface arrangement of the neoplastic cells. However, in a tumour where surface alterations may reflect both changes in endocrine function and malignant potential, the interpretation of isolated morphological findings is extremely difficult.

Adenocarcinoma↗
PubMedDate not supplied

Diagnostic ultrastructural pathology--sub-speciality or special stain?

The high resolving power of the electron microscopy gives ultrastructural pathology many of the features of a 'sensitive, multipurpose stain'. But the high resolution gives rise to problems of evaluation since most pathological features of disease are specific in a quantitative rather than in a qualitative way. Thus, pathological changes may be of diagnostic importance when they are severe enough to be seen by light microscopy, but less so when only revealed by electron microscopy. Problems of evaluation and interpretation should not lead to paralysing nihilism but should make us realize that electron microscopy does not represent the ignorant pathologist's key to a diagnostic heaven, no more than do special stains, histochemistry and immunocytochemistry. At present it may be necessary to organize ultrastructural pathology as a kind of sub-speciality of pathology. In the long run, we feel that sub-specialities should be related to the object studied rather than to the instrument used. Thus, the neuropathologist should do ultrastructural neuropathology, the cytologist ultrastructural cytopathology, etc. in the same way as most kidney pathologists already do their own ultrastructural work.

Diagnosis, Differential↗
PubMedDate not supplied

Cellular DNA content in normal human thyroid: a flow cytometric study based on frozen biopsy material.

A method is presented for preparing conventionally frozen biopsy material of thyroid tissue for flow cytometric measurement of DNA content in individual cells. The accuracy of the method was established by measuring cell suspensions of 24 biopsies of normal thyroid tissue from 20 patients. Biopsy material immersed in Histocon preservative solution prior to freezing was found to give better results than material frozen dry. All samples were found to have approximately the same modal DNA value (i.e. diploid), as determined by calibration of the fluorescence measurement with a standard of fluorescent microspheres. It was found that for an unknown sample, a deviation in modal DNA content of more than 13-14 per cent from diploid can be classified as significant by this technique.

Cell Aggregation↗