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Background The validity of circulating tumour DNA (ctDNA) as an indicator of disease progression compared to medical imaging in patients with metastatic melanoma requires detailed evaluation.Methods Here, we carried out a retrospective ctDNA analysis of 108 plasma samples collected at the time of disease progression. We also analysed a validation cohort of 66 metastatic melanoma patients monitored prospectively after response to systemic therapy.Results ctDNA was detected in 62% of patients at the time of disease progression. For 67 patients that responded to treatment, the mean ctDNA level at progressive disease was significantly higher than at the time of response (P < 0.0001). However, only 30 of these 67 (45%) patients had a statistically significant increase in ctDNA by Poisson test. A validation cohort of 66 metastatic melanoma patients monitored prospectively indicated a 56% detection rate of ctDNA at progression, with only two cases showing increased ctDNA prior to radiological progression. Finally, a correlation between ctDNA levels and metabolic tumour burden was only observed in treatment naïve patients but not at the time of progression in a subgroup of patients failing BRAF inhibition (N = 15).Conclusions These results highlight the low efficacy of ctDNA to detect disease progression in melanoma when compared mainly to standard positron emission tomography imaging.Subject terms: Tumour biomarkers, Biomarkers  相似文献   
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Patients with large sub-pulmonic ventricular septal defect (VSD) present early as a results of their complications. Some present late, due to the restriction of VSD by the right coronary cusp (RCC) due to its prolapse. In this report, we present a rare case of sub-pulmonic VSD in a 33-year-old man who developed a sub-pulmonic stenosis due to the prolapse of the RCC into the right ventricular outflow tract.  相似文献   
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Accurate assessment of etiology of mitral regurgitation (MR) is one of the key steps in the decision-making process and further clinical management of patients with severe MR. Our clinical case illustrates the added value of three-dimensional echocardiography (3DE) in assessment of mitral valve morphology and identification of an unexpected mechanism of MR which was not previously diagnosed using conventional echocardiography. 3DE helped to choose appropriate management strategy in this patient.  相似文献   
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Epstein-Barr virus lymphoproliferation after bone marrow transplantation   总被引:16,自引:7,他引:16  
We review 15 cases of secondary B-cell lymphoproliferative disorders that occurred among 2,475 patients who received allogeneic bone marrow transplants (BMTs) at the Fred Hutchinson Cancer Research Center (Seattle) between 1969 and 1987. The histopathologic findings in 14 of the 15 patients spanned a wide spectrum of lymphoproliferative lesions. One patient had features characteristic of angioimmunoblastic lymphadenopathy. Epstein-Barr virus (EBV) genomic sequences were identified by Southern blot analysis in each of the 13 patients evaluated. Ten of the 12 lesions evaluated originated in donor cells. In two patients, who had mixed chimerism after transplantation, the lesions originated in host cells. The combined evidence from immunoglobulin light chain staining and the analysis of immunoglobulin heavy chain gene rearrangement indicated that the lesions in most patients represented polyclonal proliferations that gave rise to clonal subpopulations. The results indicate an overall actuarial incidence of 0.6% for this complication in BMT recipients. Anti-CD3 monoclonal antibody (MoAb) treatment of acute graft-v-host disease (GVHD) and T cell depletion of the donor marrow were statistically significant risk factors, and GVHD appeared to play a contributing role, particularly in the setting of human leukocyte antigen (HLA) disparity. Two patients had no identifiable risk factors. Prophylaxis or treatment with acyclovir had no detectable effect in the patients; all but two died with uncontrolled lymphoproliferation.  相似文献   
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AIMS--To investigate the effect of pregnancy on serum concentrations of lipids, lipoproteins, and apolipoproteins. METHODS--Fasting serum concentrations of total cholesterol, triglyceride, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL), apolipoproteins AI, AII, and B, and lipoprotein (a) were measured in 178 women with normal glucose tolerance in the second and third trimesters of pregnancy and in a control group of 58 non-pregnant women of similar age. Data were analysed using the unpaired t test and by one-way analysis of variance. RESULTS--The pregnant women had significantly higher concentrations of total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, and apolipoproteins AI and B (p < 0.001) and apolipoprotein AII (p = 0.003) than the control women. The ratio of apolipoprotein B:apolipoprotein AI was significantly higher in the pregnant women than in the controls (p < 0.001), but the total cholesterol:HDL cholesterol ratio was not significantly different. No significant difference was found in the concentration of lipoprotein (a). CONCLUSIONS--Hyperlipidaemia is common in the second half of pregnancy. This may be a purely physiological response to pregnancy or it may be indicative of pathology in some women. These results warrant a follow up study to investigate whether the hyperlipidaemic response to pregnancy is variable and if so, whether it can predict future hyperlipidaemia in a manner analogous to that of impaired glucose tolerance during pregnancy, predicting non-insulin dependent diabetes in later life.  相似文献   
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