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Purpose

The purpose of this study was to assess the potential of a deep learning model to discriminate between benign and malignant breast lesions using magnetic resonance imaging (MRI) and characterize different histological subtypes of breast lesions.

Materials and methods

We developed a deep learning model that simultaneously learns to detect lesions and characterize them. We created a lesion-characterization model based on a single two-dimensional T1-weighted fat suppressed MR image obtained after intravenous administration of a gadolinium chelate selected by radiologists. The data included 335 MR images from 335 patients, representing 17 different histological subtypes of breast lesions grouped into four categories (mammary gland, benign lesions, invasive ductal carcinoma and other malignant lesions). Algorithm performance was evaluated on an independent test set of 168 MR images using weighted sums of the area under the curve (AUC) scores.

Results

We obtained a cross-validation score of 0.817 weighted average receiver operating characteristic (ROC)-AUC on the training set computed as the mean of three-shuffle three-fold cross-validation. Our model reached a weighted mean AUC of 0.816 on the independent challenge test set.

Conclusion

This study shows good performance of a supervised-attention model with deep learning for breast MRI. This method should be validated on a larger and independent cohort.  相似文献   
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Haploidentical stem cell transplantation (haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) is an alternative treatment for acute myeloid leukemia (AML) patients who lack HLA-matched donors. Relapse after haplo-SCT remains a major concern, especially after nonmyeloablative conditioning regimens. Promising results were reported for TBF-based conditioning regimens (thiotepa, busulfan, and fludarabine) in patients transplanted from different categories of donors and for various disease types but not specifically in PT-Cy haplo-SCT for AML. Here we evaluate the outcome of 100 AML patients who received haplo-SCT with PT-Cy after TBF conditioning regimens (reduced-intensity conditioning, n = 77; myeloablative conditioning, n = 23) in 2 transplant programs. Cumulative incidences of grades III to IV acute and moderate or severe chronic graft-versus-host disease (GVHD) were 7% and 14%, respectively. NRM at 2 years was 28%, significantly influenced by disease status at haplo-SCT (first complete response [CR1] versus advanced AML: 16% versus 38%, P = .016) but not by conditioning intensity or age. The cumulative incidences of relapse at 2 years were 17% and 24% in CR1 and advanced AML, respectively (not significant). Progression-free survival, overall survival, and GVHD and relapse-free survival at 2 years were 67%, 71%, and 49% in CR1 patients, respectively, whereas comparative values in patients with advanced disease were 37%, 41%, and 32%. Our study suggests that TBF conditioning for PT-Cy haplo-SCT is safe and effective for AML patients in CR1. In patients with more advanced disease, the relatively low incidence of relapse seems counterbalanced by a high nonrelapse mortality, underlining the need for alternative strategies to decrease relapse risk, without increasing the intensity of conditioning regimen.  相似文献   
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Late allograft failure (LAF) is a common cause of end stage renal disease. These patients face interrelated challenges regarding immunosuppression management, risk of graft intolerance syndrome (GIS), and sensitization. This retrospective study analyzes sensitization, pathology, imaging, and transfusion requirements in 33 LAFs presenting either with GIS (22) or grafts remaining quiescent (11). All patients underwent immunosuppression weaning to discontinuation at LAF. Profound increases in sensitization were noted for all groups and occurred in the GIS group prior to transplant nephrectomy (TxN). Patients with GIS experienced a major upswing in sensitization at, or before the time of their symptomatic presentation. For both GIS and quiescent grafts, sensitization appeared to be closely linked to immunosuppression withdrawal. Most transfusion naïve patients became highly sensitized. Fourteen patients in the GIS group underwent TxN which revealed grade II acute cellular rejection or worse, with grade 3 chronic active T‐cell‐mediated rejection. Blinded comparisons of computed tomography scan of GIS group revealed swollen allografts with fluid collections compared with the quiescent allografts (QAs), which were shrunken and atrophic. The renal volume on imaging and weight of explants nearly matched. Future studies should focus on interventions to avoid sensitization and GIS.  相似文献   
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BackgroundEvidence from randomized controlled trials has demonstrated benefits in quality of life outcomes from early palliative care concurrent with standard oncology care in patients with advanced cancer. We hypothesized that there would be earlier referral to outpatient palliative care at a comprehensive cancer center following this evidence.Materials and MethodsAdministrative databases were reviewed for two cohorts of patients: the pre‐evidence cohort was seen in outpatient palliative care between June and November 2006, and the post‐evidence cohort was seen between June and November 2015. Timing of referral was categorized, according to time from referral to death, as early (>12 months), intermediate (>6 months to 12 months), and late (≤6 months from referral to death). Univariable and multivariable ordinal logistic regression analyses were used to determine demographic and medical factors associated with timing of referral.ResultsLate referrals decreased from 68.8% pre‐evidence to 44.8% post‐evidence; early referrals increased from 13.4% to 31.1% (p < .0001). The median time from palliative care referral to death increased from 3.5 to 7.0 months (p < .0001); time from diagnosis to referral was also reduced (p < .05). On multivariable regression analysis, earlier referral to palliative care was associated with post‐evidence group (p < .0001), adjusting for shorter time since diagnosis (p < .0001), referral for pain and symptom management (p = .002), and patient sex (p = .04). Late referrals were reduced to <50% in the breast, gynecological, genitourinary, lung, and gastrointestinal tumor sites.ConclusionsFollowing robust evidence from trials supporting early palliative care for patients with advanced cancer, patients were referred substantially earlier to outpatient palliative care.Implications for PracticeFollowing published evidence demonstrating the benefit of early referral to palliative care for patients with advanced cancer, there was a substantial increase in early referrals to outpatient palliative care at a comprehensive cancer center. The increase in early referrals occurred mainly in tumor sites that have been included in trials of early palliative care. These results indicate that oncologists’ referral practices can change if positive consequences of earlier referral are demonstrated. Future research should focus on demonstrating benefits of early palliative care for tumor sites that have tended to be omitted from early palliative care trials.  相似文献   
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Apple proliferation phytoplasmas are considered as quarantine organisms in Europe and north America, but reliable polymerase chain reaction (PCR) primers for their identification in routine diagnosis were missing, because they show genetic variability. Therefore, 100 apple proliferation phytoplasma isolates, derived from most of the European countries where apple proliferation disease has been detected, were analysed for their genetic variability. A detailed restriction fragment length polymorphism (RFLP) analysis of a 1.5 kbp chromosomal DNA fragment amplified by PCR (PCR-RFLP) from various isolates of apple proliferation phytoplasma revealed three different subtypes named AP, AT-1 and AT-2. Sequence analysis of a 846 bp fragment of each subtype showed that the sequences differed only in the restriction sites responsible for the observed polymorphism. Thus, the apple proliferation phytoplasma subtypes are very closely related. The observed point mutations were responsible for specific amino acid changes in the putative protein PR3. No geographic prevalence of a given subtype could be observed. In a 5-year study a given subtype could be repeatedly amplified from the same tree indicating a stable maintenance of the subtype. The AP-specific primers used in this study enabled a one-step identification of all isolates suitable for routine diagnosis Copyright 2000 Academic Press.  相似文献   
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We describe our 9-year experience with lectin-treated T-cell-depleted haplocompatible parental bone marrow transplantation (BMT) for 24 patients with severe combined immunodeficiency disease (SCID). Nineteen of 21 evaluable patients had T-cell engraftment; 2 of 11 patients tested had B-cell and monocyte engraftment. Fourteen of 24 (58%) patients are alive 7 months to 9.8 years post-BMT. Seventeen of 24 patients received pretransplant conditioning with chemotherapy and/or total body irradiation, and 8 of 24 received more than one transplant. Patients who received conditioning had a survival rate of 61% versus 57% for those who received no conditioning. None received graft-versus- host disease (GVHD) prophylaxis and no patient had acute or chronic GVHD greater than grade I. Kinetics and follow-up of immune recovery were analyzed in 14 patients who are greater than 1 year from transplant. Half of the patients showed evidence of T-cell function by 3 months and normal T-cell function by 4 to 7 months post-BMT. On average, T-cell numbers and subsets became normal 10 to 12 months posttransplant. Recovery of B-cell function was more delayed, although in most patients B-cell numbers and IgM levels were normal by 12 months post-BMT. B-cell function, as determined by isohemagglutinin titers or specific antibodies to pneumococcal polysaccharide, keyhole limpet hemocyanin, or tetanus toxoid, became normal in 10 of 14 patients 2 to 8 years post-BMT. Seven of the 14 are off gammaglobulin therapy. Production of isohemagglutinins tended to predict recovery of antibody response to pneumococcal polysaccharide (P < .064). Based on these results, we believe that haplocompatible BMT is an effective, curative treatment for patients with SCID who lack an HLA-matched related donor.  相似文献   
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