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1.

Background

Available models for predicting lymph node invasion (LNI) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP) might not be applicable to men diagnosed via magnetic resonance imaging (MRI)-targeted biopsies.

Objective

To assess the accuracy of available tools to predict LNI and to develop a novel model for men diagnosed via MRI-targeted biopsies.

Design, setting, and participants

A total of 497 patients diagnosed via MRI-targeted biopsies and treated with RP and extended pelvic lymph node dissection (ePLND) at five institutions were retrospectively identified.

Outcome measurements and statistical analyses

Three available models predicting LNI were evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analyses. A nomogram predicting LNI was developed and internally validated.

Results and limitations

Overall, 62 patients (12.5%) had LNI. The median number of nodes removed was 15. The AUC for the Briganti 2012, Briganti 2017, and MSKCC nomograms was 82%, 82%, and 81%, respectively, and their calibration characteristics were suboptimal. A model including PSA, clinical stage and maximum diameter of the index lesion on multiparametric MRI (mpMRI), grade group on targeted biopsy, and the presence of clinically significant PCa on concomitant systematic biopsy had an AUC of 86% and represented the basis for a coefficient-based nomogram. This tool exhibited a higher AUC and higher net benefit compared to available models developed using standard biopsies. Using a cutoff of 7%, 244 ePLNDs (57%) would be spared and a lower number of LNIs would be missed compared to available nomograms (1.6% vs 4.6% vs 4.5% vs 4.2% for the new nomogram vs Briganti 2012 vs Briganti 2017 vs MSKCC).

Conclusions

Available models predicting LNI are characterized by suboptimal accuracy and clinical net benefit for patients diagnosed via MRI-targeted biopsies. A novel nomogram including mpMRI and MRI-targeted biopsy data should be used to identify candidates for ePLND in this setting.

Patient summary

We developed the first nomogram to predict lymph node invasion (LNI) in prostate cancer patients diagnosed via magnetic resonance imaging-targeted biopsy undergoing radical prostatectomy. Adoption of this model to identify candidates for extended pelvic lymph node dissection could avoid up to 60% of these procedures at the cost of missing only 1.6% patients with LNI.  相似文献   
2.
BACKGROUND & AIMS: Many patients with chronic hepatitis C virus (HCV) have persistently normal serum alanine transaminase (ALT) levels. We compared characteristics of chronic hepatitis C patients with patients with normal and elevated ALT levels using data from 3 randomized phase III trials of peginterferon alfa-2a (40 kDa). METHODS: The characteristics of 480 patients with normal ALT values (on >or=3 occasions without any increases in ALT level over a 6- to 18-month period) and 1993 patients with elevated ALT levels were compared. Sixty-eight of the 480 patients with normal ALT levels were randomized to no treatment and monitored for 72 weeks. RESULTS: More patients with normal ALT levels than patients with elevated ALT levels were women (59% vs 32%; P<.01). The serum HCV RNA titer was significantly lower in patients with normal ALT levels (P<.01 vs in patients with elevated ALT levels). Patients with normal ALT levels had significantly lower inflammation and fibrosis scores on liver biopsy examination than patients with elevated ALT levels, but almost two-thirds had portal fibrosis and 10% had bridging fibrosis. No correlation between baseline ALT activity, HCV RNA level, and liver histology was observed in patients with normal ALT levels. During the 72-week follow-up period, ALT activity elevated above the upper limit of normal in 53% of the untreated patients with normal levels of ALT. None became HCV RNA undetectable. CONCLUSIONS: Chronic hepatitis C patients with normal ALT levels should be evaluated in a similar manner as patients with elevated ALT levels because they are at risk for developing significant liver disease. The decision to treat with peginterferon alfa and ribavirin should be based on multiple factors, rather than on ALT levels alone.  相似文献   
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Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.

The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants.  相似文献   
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AIM: To determine the influence of Type 1 diabetes mellitus on circulating adipocytokines in children. METHODS: The circulating concentrations of leptin, adiponectin, resistin and tumour necrosis factor (TNF)-alpha were measured in 91 children, aged 11.1 +/- 2.7 years, with Type 1 diabetes mellitus (T1DM). Ninety-one healthy children were selected as control subjects. RESULTS: Body mass index-adjusted leptin concentrations were higher in the pubertal diabetic children compared with the control children. There was a significant positive correlation between leptin and daily insulin dose in the diabetic group. Circulating adiponectin concentrations were higher in the prepubertal diabetic children and were positively associated with HbA(1c). Resistin concentrations were lower in the prepubertal non-diabetic subjects compared with the pubertal non-diabetic children, whose values were higher than those of the diabetic children. TNF-alpha concentrations were similar in non-diabetic and diabetic children. CONCLUSIONS: Circulating concentrations of adipocytokines are abnormal in Type 1 diabetic children, although the direction of change differs by cytokine. Pubertal development, in addition to insulin treatment and glycaemic control, also influences the concentrations.  相似文献   
8.
BACKGROUND CONTEXT: Paraspinal infections after zygapophyseal (facet) radiofrequency denervation (RFD) are a serious but rare complication of this procedure. We are aware of only one case report of an epidural abscess after facet joint injection. PURPOSE: To report post-procedure inflammatory changes after cervical facet RFD. STUDY DESIGN: Case report. PATIENT SAMPLE: A 35-year-old Caucasian female. METHODS: Retrospective case review. RESULTS: The patient underwent cervical RFD and was admitted to the hospital 7 days after her procedure with severe neck pain. Magnetic resonance imaging (MRI) with contrast revealed what appeared to be evidence of a paraspinal muscle abscess although blood tests were negative. She was treated with antibiotic therapy, yet she never developed systemic signs of infection. A follow-up MRI without contrast revealed no evidence of infection, and she was discharged home on hospital day 6. At her first follow-up visit, she was still experiencing scalp pain and paraspinal muscle spasm. During subsequent follow-up visits, she has continued to improve clinically without experiencing signs of infection. Another follow-up MRI 6 weeks after her discharge home revealed persistent minimal left paraspinal enhancement at C2-3, possibly representing post-procedure granulation tissue with no evidence of abscess. CONCLUSIONS: Post-procedural MRI findings after radiofrequency lesioning can resemble radiographic findings associated with a paraspinal abscess. Patients with radiographic findings consistent with abscess should only be treated if clinical signs or symptoms of systemic infection are present.  相似文献   
9.
BACKGROUND: Homocysteine (Hcy) is an independent risk factor for cardiovascular disease (CVD). Individuals with Type 1 and Type 2 diabetes are more susceptible to the effects of homocysteine than non-diabetic subjects. The interaction between homocysteine-thiolactone (Hcy-thiolactone), a reactive product of Hcy, and low-density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL) and it has been suggested that homocysteinylation could increase atherogenicity of lipoproteins. AIM: The aim of the study was to compare the effect of in vitro homocysteinylation of LDL isolated from healthy control subjects (C-LDL) and from Type 1 diabetic patients (DM-LDL) and to investigate the effect of homocysteinylated LDL (Hcy-C-LDL and Hcy-DM-LDL) on peroxynitrite production of endothelial cells. METHODS: The in vitro homocysteinylation of LDL isolated from control (n = 12) and DM subjects (n = 12) was carried out by incubating lipoproteins with Hcy-thiolactone. The reaction was verified by quantifying the increase in sulphydryl groups (-SH groups) in Hcy-LDL with respect to control LDL. Control and homocysteinylated LDL were incubated with human aortic endothelial cells (HAEC) in culture. Peroxynitrite production in cells treated in different experimental conditions was assayed by a fluorimetric method. RESULTS: The increase in -SH groups after incubation with homocysteine was greater in LDL from diabetic subjects compared with LDL from control subjects (P < 0.001). In addition, peroxynitrite production from HAEC incubated with Hcy-LDL from diabetic patients was greater than after incubation with Hcy-LDL from control subjects and untreated LDL from diabetic patients (P < 0.001). CONCLUSIONS: These results show that LDL from diabetic patients is more susceptible to in vitro homocysteinylation than LDL from non-diabetic individuals and demonstrate that the compositional changes in Hcy-LDL from diabetic subjects have cytotoxic effects on human endothelial cells.  相似文献   
10.
A group of blood donors involved in post-transfusion hepatitis was investigated for the presence of the anti-HCV antibody and of HCV RNA as a more direct infection marker. RNA was extracted from serum, reverse transcribed and amplified using primers which belonged to the non structural region. The amplified product of the PCR reaction was 582 base pairs. Seven (25.9%) of the 27 blood donors examined were found anti-HCV-positive by ELISA; five (71.4%) of these were HCV RNA positive. Among the 20 anti-HCV-negative blood donors, four (20.0%) were HCV RNA positive. ALT levels were below 45 UI/l in 18 donors, while the other nine had ALTs over the limit accepted for transfusion. The anti-HCV-negative HCV RNA-positive blood donors had normal ALTs. Our study offers a direct explanation for the substantial proportion of residual cases of anti-HCV-positive post-transfusion hepatitis and suggests the necessity of creating a register of blood donors who have at some time presented blood enzyme abnormalities and for whom second level investigations such as HCV RNA should be used.  相似文献   
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