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M L Morassi

Publications and source records attributed to M L Morassi.

8 recordsLinked to original sources

[Prevalence and aggressiveness of thyroid carcinoma with diameter less than one centimetre in iodine deficiency areas].

BACKGROUND: The introduction of highly sensitive imaging techniques has made it possible to detect many non-palpable thyroid nodules with size less than 1 centimetre. The prevalence of these lesions appears to be high in the general population and increases in iodine deficiency areas. Fine needle aspiration biopsy (FNAB) is considered the most reliable test for the diagnosis of thyroid nodules. METHODS: From January 1991 to December 2000, 6627 nodules were referred for FNAB to our department. In 4871 (73.5%) euthyroid patients the mean daily urinary excretion of iodine was 73+/-18 micromg/day. RESULTS: In 2401 nodules (36.2%) the diameter was less than one centimetre. Histologic confirmation of malignancy was available in 187 (89.9%) of 208 operated nodules with diameter more than 1 cm and in 64 (78%) of 82 with diameter less than 1 cm. Logistic regression analysis indicated that a solid hypoechoic feature was a useful criterion to predict malignancy (p<0.001), as well as the presence of calcification (p<0.5) and blurred margins (p<0.5). Lymph node metastases were present in 24.3% of carcinomas with diameter more than 1 cm but, surprisingly, also in 20.3% of those with diameter less than 1 cm. No correlation was seen between diameter of carcinoma nodules and presence of lymph node metastasis. CONCLUSIONS: These data suggest that the potential malignancy of thyroid nodules is not only correlated to the diameter but to other parameters such as the biological difference of thyroid cancer that could be hypothesized in an iodine deficiency area. In conclusion, FNAB is recommended for nodules with diameter less than 1 centimetre when sonographic findings suggest malignancy such as a hypoechoic pattern, an irregular margin or internal microcalcification.

Adenocarcinoma, Follicular↗

bcl-2 expression in pleural and extrapleural solitary fibrous tumours.

This study evaluated the immunoreactivity for bcl-2, a molecule involved in the control of programmed cell death, in cases of pleural (14) and extrapleural (2) solitary fibrous tumour (SFT), malignant mesotheliomas of different histological types, and a variety of extrapleural CD34-positive and CD34-negative spindle-cell tumours. In all SFTs, strong and diffuse immunostaining was demonstrated with anti-bel-2 antibody, sharply contrasting with the complete lack of staining observed in all mesotheliomas. The specificity of immunodetection of bcl-2 in SFT was confirmed by immunoblot analysis, showing a band consistent with the bcl-2 protein. At extrapleural locations, strong bcl-2 immunoreactivity was observed in Schwannoma (2/3 cases), synovial sarcoma (4/4 cases), and all cases of CD34-positive gastrointestinal stromal tumour (GIST; 10/10 cases). Most sarcomas were bcl-2-negative. Lack of bcl-2 expression was demonstrated in tumours which can pose problems in the differential diagnosis of SFT and can exhibit haemangiopericytoma-like features, including haemangiopericytoma (3 cases), dermatofibrosarcoma protuberans (16 cases), and deep-seated fibrous histiocytoma (3 cases). The constitutive expression of bcl-2 in SFT widens the spectrum of available markers for these tumours, providing a useful adjunct to their differential diagnosis in difficult cases at pleural and extrapleural sites, and contributing to the understanding of their histogenesis and molecular pathogenesis.

Adult↗

Usefulness of the scraping method for DNA flow cytometry in breast tumors.

Flow cytometric DNA analysis is an important prognostic tool in breast cancer. We evaluated the possibility of performing DNA analysis on cell suspensions obtained by scraping the cut surface of breast tumors; 31 breast tumor nodules, including six benign and 25 malignant lesions, were studied. From each case, cell suspensions acquired by mechanical mincing of a fresh frozen tissue fragment and by two different scrapings (central and peripheral) from the cut surface of the tumor were analyzed via flow cytometry. In all cases, comparison of the DNA histograms for three samples showed no significant differences in the appearance of debris or in the value of coefficient of variation of the G0-G1 peak. All benign nodules showed a normal DNA stemline in all specimens. In 23 of 25 cases of breast carcinoma, the ploidy of the three preparations was similar, with a concordance in 12/14 (85, 71%) cases in DNA nondiploid tumors. Linear regression analysis showed a good correlation in DNA index between either scraping sample and the tissue fragment (r = .955 and r = .905). The results indicate that the scraping technique provides excellent cell suspensions and DNA histograms comparable to those obtained from mechanical mincing of tissue fragments. The technique minimizes preparation time and avoids consuming much tissue and, thus, is the method of choice when very small cancers have to be analyzed.

Biopsy↗

[Melanoma metastatic to the trachea and nasal cavity: description of a case and review of the literature].

Secondary tumors of the trachea are exceedingly rare, only 14 cases having been reported in the literature. Moreover, metastatic involvement of naso-paranasal cavities can be considered quite unusual. Approximately 150 cases have been drawn from the literature, most of which presented a metastatic deposit from a renal adenocarcinoma. Report is then made of a case of cutaneous melanoma metastatic to the trachea and nasal cavity. The tracheal lesion was repeatedly treated with Nd Yag laser, whereas no treatment was considered eligible for nasal metastasis. The patient succumbed to the tumor 16 months after diagnosis of tracheal involvement had been made. The tendency for malignant melanomas to metastasize to distant organs via the bloodstream is well known, yet trachea and nasoparanasal involvement by metastatic melanoma has been reported, respectively, in only three and six cases, including the present one. Prognosis is unfavorable due to the unusual coexistence of metastases to other organs and the lack of an adequate treatment.

Humans↗