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121.
We evaluated the diagnostic utility of simultaneous determination of 5 tumor markers, CEA, CA 125, CA 15-3, CA 19-9 and cytokeratin 19 (CYFRA 21-1), in fluid and serum from 101 patients, 52 with pleural effusion (22 malignant) and 49 patients with ascites (14 malignant). Tumor marker concentrations in fluid from patients with malignant effusions were significantly higher than those obtained in benign fluids or serum. However, there are two types of tumor markers: those released/secreted by normal mesothelia such as CA 125 and cytokeratin 19 (higher levels in benign fluids than in serum) and non-released/secreted tumor markers (low concentrations in benign fluids) such as CEA, CA 19-9 and CA 15-3. The fluid/serum (F/S) ratio showed better sensitivity with maximum specificity than a single determination in fluid for CEA, CA 15-3 and CA 19-9, but not for CA 125 and CYFRA. The combination of a F/S ratio greater than 1.2 and a cut-off of 5 ng/ml for CEA, 30 U/ml for CA 15-3 and 37 U/ml for CA 19-9 showed sensitivities of 58, 57 and 44%, respectively, and a specificity of 100%, with a combined sensitivity of 82% for overall effusions and 79% for fluids with negative cytology with a specificity of 100%. In conclusion, the use of the F/S ratio in nonsecreted tumor markers such as CEA, CA 19-9 and CA 15-3 improve the sensitivity and specificity and allow standardization of the cut-off.  相似文献   
122.
PURPOSE: To assess tolerance and efficacy of preoperative treatment with uracil/tegafur and radiotherapy (RT) followed by surgery and postoperative flurouracil (FU)/leucovorin (LV) in patients with rectal cancer. PATIENTS AND METHODS: Patients (n = 94) with potentially resectable tumors, ultrasound at stages T2N+ (n = 4), T3 (n = 77), T4 (n = 13) were treated with UFT (400 mg/m2/d, 5 days a week for 5 weeks) and concomitant RT to the pelvis (45 Gy; 1.8 Gy/d over 5 weeks). Patients underwent surgery 5 to 6 weeks later followed by four cycles of FU/LV. Primary end points included downstaging, pathologic responses, and sphincter-preserving surgery. Secondary end points were recurrence-free survival and overall survival. RESULTS: All patients received the full RT dose. Fifteen patients (16%) needed UFT dose reduction. Preoperative G3+ toxicities included diarrhea (14%), leukopenia (1%), thrombocytopenia (1%), and nausea (4%). The downstaging rate was 54%, pathologic complete response (pCR) was 9% and, in an additional 23%, there were only residual microscopic foci. When cellular viability criteria were taken into account, the pCR was 15%. From 43 patients with abdominoperineal resection indication, 11 (25%) had sphincter-preserving surgery performed. Postoperative scheduled chemotherapy dose was not administered to 24% of patients because of G3+ toxicity (diarrhea, 8%; mucositis, 9%; and leukopenia, 7%). Patients with downstaging had significantly higher survival and recurrence-free survival rates than those without. At 3 years, actuarial patterns of failure were pelvic, 5% and distant, 11%. OS was 75%. CONCLUSION: UFT combined with RT is safe and effective. In resectable rectal cancer, if preoperative treatment is considered, this approach can be an option.  相似文献   
123.
Objective: To study the insulin-like growth factor-1 (IGF-1) axis in hirsute women.

Design: Controlled clinical study.

Setting: Tertiary care institutional hospital.

Patient(s): Forty hirsute women and 17 women with normal menstrual cycles.

Intervention(s): Basal and ACTH-stimulated samples were obtained, and sampling was repeated 1 (gonadal stimulation) and 21 (gonadal suppression) days after a single 3.75-mg IM dose of triptorelin. Controls did not receive triptorelin for ethical reasons.

Main Outcome Measure(s): Serum GH, IGF-1, IGF-binding protein-3 (IGFBP-3), insulin, glucose, total testosterone, sex hormone-binding globulin, E2, and gonadotropin levels. Basal and ACTH-stimulated steroid precursors were measured.

Result(s): Patients with idiopathic hirsutism were identified by normal serum androgen levels (n = 17). Those with functional ovarian hyperandrogenism (n = 15) were identified by an increase in the serum testosterone level that normalized during gonadal suppression, whereas those with functional adrenal hyperandrogenism (n = 8) were identified by an initial increase in the testosterone level that persisted during gonadal suppression. The adrenal hyperandrogenism group had increased IGF-1 levels compared with the control, idiopathic hirsutism, and ovarian hyperandrogenism groups. Patients with ovarian hyperandrogenism had normal IGF-1 concentrations, but their IGFBP-3 concentrations were lower than those of controls. No differences were observed in GH levels between any of the groups. These results persisted when the influence of age was corrected for.

Conclusion(s): The IGF-1 axis appears to be involved in the pathogenesis of hyperandrogenism, especially in patients with adrenal hyperandrogenism, who have a clear increase in IGF-1 levels. Moreover, patients with ovarian hirsutism have decreased IGFBP-3 concentrations, which might enhance IGF-1 bioavailability.  相似文献   

124.
125.
INTRODUCTION: Presence of circulating DNA in the serum of patients with cancer makes detection of tumour-specific genetic alterations feasible. OBJECTIVE: To study serum DNA concentration in patients diagnosed as having advanced Non-Small Cell Lung Cancer (NSCLC) and to evaluate its relationship with age, histology, stage, response, time-to-progression (TTP), and survival. METHODS: Serum DNA from 78 patients was purified and spectrophotometrically quantified. RESULTS: No significant correlations were found between serum DNA concentration and age, histology, response and survival. There was a significant correlation with respect to stage (IIIB = 408.75 ng/ml; IV = 478.74 ng/ml; p = 0.02). When patients were grouped according to DNA concentration, significant correlation with TTP was found; establishing a cut-off point at 500 ng/ml ([DNA] < 500 ng/ml TTP = 7.25 months, 95%CI: 3.5-5.25; [DNA ] > or = 500 ng/ml TTP = 4.25 months, 95%CI: 2-6.5; p = 0.05). CONCLUSIONS: Using the present method, DNA concentration quantification appears to be simple, but with certain deficiencies due to inter-sample variability and low specificity. This is because total DNA concentration is measured without distinguishing as to whether it is tumour-related. We suggest that there is a correlation between DNA concentration and prognosis which enables an analysis of the natural history of the disease.  相似文献   
126.
PURPOSE: Monoclonal gammopathy of undetermined significance (MGUS) progresses to multiple myeloma or another related plasma cell disorder (PCD) at a rate of approximately 1% per year. Identification of patients with MGUS at high risk of progression will allow development of preventive strategies. We studied the prognostic value of circulating plasma cells (PCs) in patients with MGUS to predict progression. PATIENTS AND METHODS: Patients were eligible for this retrospective analysis if they were seen at the Mayo Clinic between 1984 and 1997, were diagnosed with MGUS, and had an analysis of the peripheral blood for circulating PCs by the slide-based immunofluorescence method. Patients were observed for progression to another PCD. RESULTS: Three hundred twenty-five patients were eligible and 63 (19%) had circulating PCs. Patients with circulating PCs were twice as likely (hazard ratio, 2.1) to experience progression to another PCD (most commonly myeloma), compared with those without circulating PCs (95% CI, 1.1 to 4.3; P = .03). In patients with circulating PCs, the median progression-free survival was 138 months compared with a median not yet reached for those without circulating PCs (P = .028). The median overall survival also was shorter for those with circulating PCs. Other factors with prognostic value were high levels of M protein and non-immunoglobulin G heavy-chain type. CONCLUSION: The presence of circulating PCs, especially when combined with other known prognostic factors such as M protein concentration and immunoglobulin isotype, identify a group of individuals with MGUS at higher risk of progression to overt multiple myeloma.  相似文献   
127.
Undifferentiated (anaplastic) thyroid carcinoma is a highly aggressive human cancer with very poor prognosis. Although there have been a few studies of candidate treatments, the fact that it is an infrequent tumor makes it very difficult to design clinical trials. A strong association has been observed between undifferentiated thyroid carcinoma and TP53 mutations in numerous molecular genetic and expression studies. Plitidepsin (Aplidin, PharmaMar, Madrid, Spain) is a novel anticancer compound obtained from a sea tunicate. This compound has been reported to induce apoptosis independently of TP53 status. We investigated the actions of plitidepsin in human thyroid cancer cells. In initial experiments using primary cultured cells from a differentiated (papillary) carcinoma, we found that 100 nmol/L plitidepsin induced apoptosis, whereas lower doses were cytostatic. Because our aim was to study the effects of plitidepsin at clinically relevant concentrations, subsequent experiments were done with a dosage regimen reflecting plasma concentrations observed in previously reported clinical trials: 100 nmol/L for 4 hours, followed by 10 nmol/L for 20 hours (4(100)/20(10) plitidepsin). This plitidepsin dosage regimen blocked the proliferation of a primary undifferentiated/anaplastic thyroid carcinoma culture obtained in our laboratory and of a commercial cell line (8305C) obtained from an undifferentiated thyroid carcinoma; however, it did not induce apoptosis. The proportion of cells in the G(1) phase of the cell cycle was greatly increased and the proportion in the S/G(2)-M phases greatly reduced, suggesting that plitidepsin blocks G(1)-to-S transition. Levels of the cyclin D1/cyclin-dependent kinase 4/p21 complex proteins were decreased and, in line with this, the levels of unphosphorylated Rb1 increased. The decrease in cell cycle proteins correlated with hypoacetylation of histone H3. Finally, we did experiments to assess how rapidly tumor cells return to their initial pretreatment proliferative behavior after 4(100)/20(10) plitidepsin treatment. Cells from undifferentiated tumors needed more than 3 days to recover logarithmic growth, and after 7 days, cell number was still significantly lower than in control cultures. 4(100)/20(10) plitidepsin inhibited the growth in soft agar. Together, our data show that plitidepsin is able to block in vitro cell cycle progression at concentrations similar to serum concentrations observed in vivo, and that this effect is persistent for several days after plitidepsin removal. Whether plitidepsin will prove to be clinically useful in the treatment of undifferentiated thyroid cancers remains to be established. However, our results raise the possibility that plitidepsin might be effective alone or in combination with radiotherapy and/or other drug treatments.  相似文献   
128.
PURPOSE: To evaluate the efficacy of reduced intensity conditioning (RIC) allogeneic transplant in 30 patients with poor-prognosis chronic lymphocytic leukemia (CLL) and/or high-risk molecular/cytogenetic characteristics. EXPERIMENTAL DESIGN: Eighty-three percent of patients had active disease at the moment of transplant. That is, 14 of the 23 patients analyzed (60%) had unmutated immunoglobulin variable heavy-chain gene (IgV(H)) status; 8 of 25 patients (32%) had 11q-, with four of them also displaying unmutated IgV(H); and six (24%) had 17p- (five were also unmutated). RESULTS: After a median follow-up of 47.3 months, all 22 patients alive are disease free; overall survival and event-free survival (EFS) at 6 years were 70% and 72%, respectively. According to molecular/cytogenetic characteristics, overall survival and EFS for unmutated CLL and/or with 11q- aberration (n = 13) were 90% and 92%, respectively, not significantly different to those with normal in situ hybridization, 13q- and +12, or mutated CLL (n = 7). All six patients with 17p deletion were transplanted with active disease, including three with refractory disease; all except one reached complete remission after the transplant and two are alive and disease free. Nonrelapse mortality (NRM) was 20%; more than two lines before transplant is an independent prognostic factor for NRM (P = 0,02), EFS (P = 0.02), and overall survival (P = 0.01). Patients older than 55 years have a higher risk of NRM (hazard ratio, 12.8; 95% confidence interval, 1.5-111). Minimal residual disease was monitored by multiparametric flow cytometry in 21 patients. Clearance of CD79/CD5/CD19/CD23 cells in bone marrow was achieved in 68% and 94% of the patients at days 100 and 360, respectively. CONCLUSION: According to these results, RIC allogeneic transplant could overcome the adverse prognosis of patients with unmutated CLL as well as those with 11q- or 17p-.  相似文献   
129.
PURPOSE: Long-term brain metastases survivors are at risk for neurologic morbidity after whole-brain radiotherapy (WBRT). Retrospective radiosurgery (RS) reports found no survival difference when compared with WBRT. Before RS alone was evaluated with delayed WBRT in a phase III trial, the feasibility of RS alone was tested prospectively. PATIENTS AND METHODS: Patients with renal cell carcinoma, melanoma, or sarcoma; one to three brain metastases; and performance status of 0 to 2 were enrolled. Exclusion criteria were leptomeningeal disease; metastases in medulla, pons, or midbrain; or liver metastases. On the basis of tumor size, patients received 24, 18, or 15 Gy RS. At recurrence, management was discretionary. The primary end point was 3- and 6-month intracranial progression. RESULTS: Between July 1998 and August 2003, 36 patients were accrued; 31 were eligible. Median follow-up was 32.7 months and the median survival was 8.3 months (95% CI, 7.4 to 12.2). Three- and 6-month intracranial failure with RS alone was 25.8% and 48.3%. Failure within and outside the RS volume, when in-field and distant intracranial failures were scored independently, was 19.3% and 16.2% (3 months) and 32.2% and 32.2% (6 months), respectively. Approximately 38% of patients experienced death attributable to neurologic cause. There were three grade 3 toxicities related to RS. CONCLUSION: Intracranial failure rates without WBRT were 25.8% and 48.3% at 3 and 6 months, respectively. Delaying WBRT may be appropriate for some subgroups of patients with radioresistant tumors, but routine avoidance of WBRT should be approached judiciously.  相似文献   
130.
Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects.  相似文献   
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