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Available results highlight the lack of good level of evidence studies on the pure prognostic value of histological grade. In the present study, the prognostic relevance of histological grade and of its three components, tubule formation, nuclear pleomorphism and mitotic count, was analyzed in a series of 372 patients with node-negative breast cancer treated with locoregional therapy alone until early relapse. Histological grade was determined blindly by two observers and discordance between evaluations was resolved after joint review using a multihead microscope. No relation was observed between histological grade and any of its three components and disease-free survival. Conversely, a significant relation was observed between histological grade and distant metastasis-free survival (at 6 years, 94, 86 and 76% for grades 1, 2 and 3, respectively, P=0.013) as well as overall survival (98, 90 and 86%, P=0.001). A breakdown analysis as a function of the three components showed that neither tubule formation nor nuclear pleomorphism was associated with prognosis, and only mitotic count strongly influenced both distant metastasis-free survival (91, 82 and 74%, P=0.014) and overall survival (97, 87 and 85%, P=0.011). Histological grade suffers from a much higher subjectivity than any other microscopic evaluation of biomarkers as it is the sum of three different morphological features. Within the Italian Network for Quality Assessment of Tumor Biomarkers program we observed that histological grade is an independent prognostic variable, but also that this role is ascribable only to the number of mitotic figures. In conclusion, due to the ever smaller size of diagnosed breast cancers, resulting in less cancer tissue for biofunctional and molecular analysis, mitotic count evaluated under strict quality control conditions seems to be an accurate and feasible prognostic variable.  相似文献   
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In the present study, the primary tumor angiogenesis characteristics of 81 stage IV previously untreated breast cancers with synchronous metastasis to different distant sites (10 patients with soft tissue metastases, 31 with bone metastases, and 40 with visceral metastases) were analyzed. The primary intratumor microvessel density was assessed by immunohistochemical assay on paraffin-embedded primary tumor samples, using a monoclonal anti-CD34 antibody. The mean primary intratumor microvessel density (at 400× fields) was 78±39 (SD) microvessels per field. The microvessel density was not significantly related to the main clinical/pathological features of the tumor (age, cytohistological grade, DNA ploidy, diameter, and receptor status). The percentage of tumor cases with high primary intratumor microvessel density (cut-off median value of the series 73±39 microvessels/field) did not significantly differ in patients with bone, soft tissue, or visceral metastatic disease. Aanalysis of clinical outcome showed a significantly shorter time to progression and overall survival for patients with visceral metastases (P<0.001 and P<0.0002 by log-rank, respectively). Presence of visceral metastases was confirmed to be the only independent prognostic factor related to a worse TTP (hazard risk 2.15, 95% confidence interval 1.14–4.03, P<0.02) and overall survival (hazard risk 1.81, 95% confidence interval 0.98–3.35, P<0.06) by multivariate analysis. In conclusion, the assessment of neoangiogenesis of primary breast cancer by CD34 expression does not provide information predictive of different distant sites of metastasis. Received: 15 June 2001 / Accepted: 12 September 2001  相似文献   
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The hormone receptor status and proliferative activity characteristics of inflammatory breast cancer (IBC) were studied in a series of 46 patients. ER and PgR were measured by the DCC method and proliferative activity was by the H-3-thymidine autoradiographic labeling index (H-3-Tdr-LI). Tumors were ER and PgR positive in 42% and 38% of cases, respectively, whereas median H-3-Tdr-LI was 3.8%. With regard to clinical aspects, overall survival (OS) was not affected by either ER status (36 cases) or H-3-Tdr-LI value (33 cases). On the contrary, PgR(+) status was able to individualize women with a significantly higher probability of OS (X(2) by long rank test, p=0.03) after 35 months of follow-up. In the subgroup of 14 patients subjected to double biopsy performed before and after administration of primary polychemotherapy, the tumor proliferative activity variations were not related to clinical outcome.  相似文献   
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Recently, a method similar to ER.ICA has been proposed for the progesterone receptor (PgR) using two monoclonal antibodies, JZB39 and KD68, specific for human PgR and characterized by a molecular weight of 95 and 120 Kd, respectively. A series of 73 breast cancer patients was studied with regards to ER and PgR using both immunocytochemical (ICA) and biochemical (DCC) assays. Results showed no substantial differences between the two methods when considering common clinical-pathological parameters. Overall agreement between ICA and DCC methods was found: 79% for PgR and 78% for ER. A slight quantitative correlation was also observed between the "score values" of the ICA method and the Fmol content of ER and PgR using the Brave-Pearson test (r = 0.49 for PgR; r = 0.43 for ER). Specificity of PgR.ICA method was 77% for PgR and 72% for ER; sensitivity was 82% and 83%, respectively. The ICA method is a reliable technique to assess PgR presence as well as ER. Further studies are necessary to evaluate the prognostic role of nuclear PgR.  相似文献   
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Chelating drugs and chelator metal complexes are used for the prevention, diagnosis and treatment of cancer. Cancer cells and normal cells require essential metal ions such as iron, copper and zinc for growth and proliferation. Chelators can target the metabolic pathways of cancer cells through the control of proteins involved in the regulation of these metals and also of other molecules involved in cell cycle control, angiogenesis and metastatic suppression. Other targets include the inhibition of specific proteins such as ribonucleotide reductase involved in DNA synthesis, the inhibition of free radical damage on DNA caused by iron and copper catalytic centers, the inhibition of microbial growth in immuno compromised cancer patients and the decorporation of radioactive and other toxic metals causing cancer. Chelating drugs and metal ions can affect the metabolism, efficacy and toxicity of anti-cancer drugs such as doxorubicin, mitozantrone, bleiomycin and hydroxyurea (HU). Although many experimental chelators have been shown to be effective as anti-cancer agents, only a few, e.g., dexrazoxane, deferoxamine (DFO) and triapine, have reached the stage of clinical testing or application. In many experimental models, deferiprone (L1) has been shown to be effective in cancer prevention and treatment, and in the inhibition of doxorubicin-induced cardiotoxicity. New anti-cancer drugs could be developed using chelators and chelator complexes with platinum and other metals, and also new protocols of combinations of chelators with known anti-cancer drugs.  相似文献   
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Severe chronic damage to the heart and gastrointestinal tract in patients with Chagas' disease are often observed 10-20 years after the acute phase. The course of long-lasting infection with the Colombian strain of Trypanosoma cruzi was studied in seven rhesus monkeys infected for 15-19 years. Subpatent parasitemia was detected in all studied animals, using hemoculture (two of seven), artificial xenodiagnosis (three of seven), and a polymerase chain reaction PCR (six of six). High titers of specific IgG antibody to T. cruzi persisted throughout the chronic phase of infection. Abnormal electrocardiographic (three of six) and echocardiographic (one of six) patterns detected in the T. cruzi-infected monkeys were possibly related to parasite-triggered myocardial damage. The results suggest that rhesus monkeys experimentally infected with T. cruzi, besides reproducing the acute phase of Chagas' disease, also develop chronic chagasic cardiomyopathy.  相似文献   
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