Anaplastic thyroid carcinoma: diagnostic challenges,histopathologic features and ancillary testing

Anaplastic thyroid carcinoma (ATC) is an aggressive thyroid malignancy with high mortality rate. This malignancy arises in thyroid follicular cells either denovo or with an associated differentiated thyroid carcinoma component. Clinically, it usually presents as a rapidly enlarging mass, pain and locally compressive symptoms. Histopathologic variability and heterogeneity often pose diagnostic challenges, especially in scant and paucicellular specimens. This article describes the clinical, histopathologic and molecular features of ATC and also addresses the associated diagnostic limitations and challenges.     

Intravenous cidofovir treatment for recalcitrant warts in the setting of a patient with myelodysplastic syndrome

Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.     

Biochemical and biological activity of the anthracycline analog, 4-demethyl-6-0-methyl-doxorubicin

Summary The chromophore-modified derivative of doxorubicin, 4-demethyl-6-0-methyl-doxorubicin, has been tested for antitumor activity in a range of experimental murine tumor systems. In contrast to the inactive 6-0-methyl derivative of daunorubicin, 4-demethyl-6-0-methyl-doxorubicin provided antitumor effects comparable to that of the parent compound. In addition, detailed DNA-interaction studies showed that the doxorubicin derivative retains the ability to bind DNA by the intercalation mechanism. However, the binding affinity was appreciably reduced following structural modification in the anthraquinone chromophore. On the basis of the proposed models of intercalation, these results could be rationalized in terms of steric influence of the bulky methoxy group. The results of this study are in agreement with the correlation already observed between DNA binding and relative antitumor activity of anthracyclines.     

Significance of cyclin D1 expression in meningiomas: a preliminary study.

Forty-four evaluable patients with intracranial meningiomas were assessed for the expression of the cell-cycle regulator cyclin D1 and of proteins involved in proliferation and apoptosis such as PCNA, MIB-1, p53 and bcl-2. Analyses were carried out by western blot and immunohistochemistry after immediate processing of fresh tumor specimens. By western blot, expression of cyclin D1 significantly correlated with p53 (p=0.02) and with proliferative activity, as assessed by PCNA expression (p=0.0009). By immunohistochemistry, a significant relationship between cyclin D1 and the proliferation marker MIB-1 was confirmed (p=0.05), whereas significance with bcl-2 expression was not found (p=0.01). Moreover, although the association with tumor grade appeared of borderline statistical significance (p=0.07), all the grade II/III meningiomas showed increased expression of cyclin D1 and high proliferative activity. In conclusion, data from this preliminary study seem to suggest a potential value of the combined expression of cyclin D1 and proliferation indicators in defining subgroups of meningiomas with a more aggressive biological behavior.     

Immunohistochemical study of colonic mucosa macrophages in children with Crohn's disease and ulcerative colitis]

In this research the histological characteristics of the macrophages on the colonic mucosa in Crohn's disease and ulcerative colitis were quantified and analysed. Twelve Crohn's disease, 19 ulcerative colitis and 10 specimen of the rectal mucosa, representing the control group according to the followed model, were studied: I period (PI) = pre-treatment, II period (PII) = up two years of evolution and III period (PIII) = more than two years of evolution. The macrophages were identified in a colonic mucosa by the monoclonal CD68 through the immunoperoxidase method. The macrophages quantification was done by chromatic computer images analysis, that express the area (mm2) used by the CD68 positive cells, in percentage. The percentage of the area used by the macrophages was increased in both diseases, in all the studied periods, when compared with the control group, but without statistic significance. The macrophages' distribution inside the control group mucosa was subepithelial, while in the illness group, it reached all the mucosa that was concentrated on the basis of ulcers and all long the fissures. On the Crohn's disease the CD68 positive cells facilited the identification of the microgranulomas, sometimes unnoticed in the hematoxiline-eosine. Although there was no difference between patients and control group in the macrophages area, the difference in the distribution could suggest the macrophages' participation on the injure in both diseases although they do not permit a differential diagnosis because of the variety of the values. The CD68 did not identify the different functional status of the macrophages, but their position in the mucosa suggest that, in terms of fissures and ulcers, their mainly function should be the phagocitosis and in the other cases, they have been the cells that should show the antigens and that recruit the other inflammatory cells.     

Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance

Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.