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2.

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   
3.
Aging is commonly defined as the accumulation of diverse deleterious changes occurring in cells and tissues with advancing age that are responsible for the increased risk of disease and death. The major theories of aging are all specific of a particular cause of aging, providing useful and important insights for the understanding of age-related physiological changes. However, a global view of them is needed when debating of a process which is still obscure in some of its aspects. In this context, the search for a single cause of aging has recently been replaced by the view of aging as an extremely complex, multifactorial process. Therefore, the different theories of aging should not be considered as mutually exclusive, but complementary of others in the explanation of some or all the features of the normal aging process. To date, no convincing evidence showing the administration of existing “anti-aging” remedies can slow aging or increase longevity in humans is available. Nevertheless, several studies on animal models have shown that aging rates and life expectancy can be modified. The present review provides an overlook of the most commonly accepted theories of aging, providing current evidence of those interventions aimed at modifying the aging process.  相似文献   
4.
We report the clinicopathologic, immunohistochemical, and ultrastructural features of three small-cell neuroendocrine carcinomas of the ampullary region of the duodenum. All patients were men; their ages were 51, 62, and 66 years. The therapy consisted of pancreatoduodenectomy. All patients died of the disease; median survival was 10 months from the diagnosis. The histological appearance was identical to pulmonary and extrapulmonary small-cell carcinoma. The neuroendocrine differentiation was demonstrated ultrastructurally by the presence of dense-core granules, and by the positive immunoreaction for neuron-specific enolase and Leu-7 in each case. One case expressed a focal positivity for chromogranin A (PHE-5) and argyrophilic granules. The same case showed the presence of neurofilaments on frozen material. Neurofilament proteins could not be demonstrated in any case in paraffin sections. Neoplastic cells exhibited cytoplasmic immunostaining for cytokeratins (CAM 5.2) in all cases. In one case, a large number of neoplastic cells (60-70%) exhibited nuclear Ki-67 positivity. We postulate that the disease's histogenesis was from epithelial stem cell expressing both epithelial and neuroendocrine characteristics. The clinical behavior of small-cell neuroendocrine carcinomas of the ampullary region appears to be extremely aggressive, with early metastases and fatal outcome.  相似文献   
5.
This study evaluates the microvascular reperfusion of ischemic skin flaps with and without acute hyperbaric oxygen (HBO) treatment. Thirty-two axial pattern epigastric skin flaps (3 x 6 cm) in male Wistar rats were subjected to 8 hours of global ischemia by pedicle clamp occlusion. The rats were divided into the following control and two experimental groups: Control (n = 12) with ischemia, no HBO; Group 1 (n = 11) with HBO treatment (three 1.75-hour dives, 2.5 absolute atm, 100% O2) during ischemia; and Group 2 (n = 9) with HBO treatment (two 1.75-hour dives) immediately after ischemia. Laser Doppler flows were recorded in two distal standardized flap locations at 0.5, 2, 4, and 18 hours after reperfusion in control rats and Group 1 rats and at 18 hours only in Group 2 rats, using a Med-Pacific 6000 laser Doppler unit. Mean distal flap laser Doppler flows (mV) were Control: 0.5 hours = 23.2 +/- 11.9, 2 hours = 52.8 +/- 27.3, 4 hours = 53.6 +/- 32.1, 18 hours = 40.2 +/- 36.2; Group 1: 0.5 hours = 71.8 +/- 30.9 (p less than 0.05 vs. control), 2 hours = 74.3 +/- 27.3, 4 hours = 67.4 +/- 20.6, 18 hours = 79.1 +/- 40.3 (p less than 0.05 vs. control); and Group 2: 18 hours = 90.3 +/- 47.9 (p less than 0.05 vs. control). It is concluded that acute HBO treatment of ischemic rat skin flaps improves distal microvascular perfusion as measured by laser Doppler flowmetry. This effect is observed for HBO treatment given either during or immediately after prolonged global ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
The aim of this study was to check the reliability of sonography in measuring small variations in quantities of subcutaneous and intra-abdominal fat. Twenty-six obese women (BMI 39 +/- 6) underwent a 15 day very low calorie diet. The study included, both before and after very low calorie diet, computed tomography measurements of total (AT), visceral (VAT) and subcutaneous (SAT) adipose tissue areas, visceral/subcutaneous area ratio (V/S), waist/hip circumference ratio measurements (W/H), and ultrasound measurements of abdominal subcutaneous skin-muscle thickness, intra-abdominal muscle-aorta thickness and intra-abdominal/subcutaneous thickness ratio. Weight reduction was from 101 +/- 17 to 95 +/- 16 kg (P less than 0.001). W/H dropped from 0.83 +/- 0.06 to 0.82 +/- 0.07 (n.s.). VAT dropped from 158 +/- 72 to 134 +/- 61 cm2 (P less than 0.005), SAT from 572 +/- 151 to 566 +/- 164 cm2 (n.s.) and V/S from 0.29 +/- 0.15 to 0.25 +/- 0.11 (P less than 0.01). Abdominal subcutaneous fat thickness decreased from 36 +/- 8 to 35 +/- 10 mm (n.s.), intra-abdominal thickness from 39 +/- 25 to 20 +/- 20 mm (P less than 0.001) and intra-abdominal/subcutaneous from 1.1 +/- 0.7 to 0.8 +/- 0.6 (P less than 0.005). VAT measurement accurately identified small intra-abdominal fat variations. W/H could not evaluate visceral fat loss, because of simultaneous decreases in waist and hip circumferences. Ultrasound was able to measure small reductions in intra-abdominal fat.  相似文献   
7.
The role of catecholaminergic mechanisms in determining the changes in the rat's preoptic cyclic adenosine monophosphate (cAMP) concentration during sleep deprivation and recovery induced by ambient temperature was investigated in the present study. To this end, the activity of tyrosine hydroxylase, the rate-limiting enzyme in catecholamine biosynthesis, was measured in the preoptic region of rats maintained in: (a) control (22 degrees C for 52 h), (b) deprivation (-10 degrees C for 52 h), and (c) recovery (22 degrees C for 4 h after 48 h at -10 degrees C) conditions. The enzyme followed a Michaelis-Menten kinetic. The analysis of substrate-related kinetic parameters (Km and Vmax) did not show any clear-cut difference between experimental conditions, which, as already known, induce both sleep deprivation and recovery in relation to significant cAMP changes.  相似文献   
8.
Functional decline in frail community-dwelling stroke patients   总被引:1,自引:0,他引:1  
Patients who suffer a stroke event are at high risk of functional decline after the post-acute rehabilitation period. The aim of the present study was the evaluation of factors associated with functional decline in a large sample of older patients with stroke living in the community. The study population consisted of all patients admitted to home care programs after a post-acute rehabilitation program--with at least 1 year of follow-up--in twenty-two Italian Home Health Agencies from 2000 to 2002 (n=1338). For the present study we selected 355 (26%) patients with diagnosis of stroke. After 1 year of in-home care program, 149 out of 355 stroke survivors (42%) had presented a worsening in the activities of daily living (ADL) scale score. In the final adjusted model, patients with cognitive impairment (OR 2.59, 95% CI, 1.45-4.64), pressure ulcer (OR 2.74, 95% CI, 1.45-5.18), urinary incontinence (OR 1.64, 95% CI, 1.01-3.29), or hearing impairment (OR 1.83, 95% CI, 1.02-3.29) were more likely to significantly decline in physical functioning after a period of 1 year in-home care program. Our study documents that functional decline of stroke patients was largely dependent on specific subjects' clinical characteristics. Three of four concomitant disabling conditions associated in our sample with functional decline--pressure ulcer, urinary incontinence, hearing--can be prevented and eventually treated or modified. Appropriate post-acute rehabilitation programs and adequate home care interventions focused on the prevention and treatment of these conditions might be correlated to better outcomes in older post-stroke patients.  相似文献   
9.
Summary The Southern blot hybridization technique has been applied to study the configuration of immunoglobulin and T-cell receptor genes in 6 cases of the so called mediastinal large cell lymphoma with sclerosis. This lymphoma has been recently recognized as a separate entity among non-Hodgkin lymphomas mainly affecting young adult patients. The B-cell origin of this neoplasm was suggested by means of immunohistochemical analysis. However, the immunophenotypical B-cell related markers used do not always exhibit lineage fidelity. The Southern blot analysis demonstrated the presence of unique heavy and k-light chain immunoglobulin gene rearrangements, establishing genotypically their B-cell origin.This work was supported by the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy, and Progetto finalizzato Oncologia (contratto no 86.00461.44), CNR, Rome, Italy. Aldo Scarpa and Maurizio Lestani are supported by a Scholarship from the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy  相似文献   
10.
A shift of physiological regulations from a homeostatic to a non-homeostatic modality characterizes the passage from non-NREM sleep (NREMS) to REM sleep (REMS). In the rat, an EEG index which allows the automatic scoring of transitions from NREMS to REMS has been proposed: the NREMS to REMS transition indicator value, NIV [J.H. Benington et al., Sleep 17 (1994) 28-36]. However, such transitions are not always followed by a REMS episode, but are often followed by an awakening. In the present study, the relationship between changes in EEG activity and hypothalamic temperature (Thy), taken as an index of autonomic activity, was studied within a window consisting of the 60s which precedes a state change from a consolidated NREMS episode. Furthermore, the probability that a transition would lead to REMS or wake was analysed. The results showed that, within this time window, both a modified NIV (NIV(60)) and the difference between Thy at the limits of the window (Thy(D)) were related to the probability of REMS onset. Both the relationship between the indices and the probability of REMS onset was sigmoid, the latter of which saturated at a probability level around 50-60%. The efficacy for the prediction of successful transitions from NREMS to REMS found using Thy(D) as an index supports the view that such a transition is a dynamic process where the physiological risk to enter REMS is weighted at a central level.  相似文献   
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