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41.
Purpose

The purpose of the study was to determine if the ≥ 15 mm threshold currently used to define PIRADS 5 lesions is the optimal size threshold for predicting high likelihood of clinically significant (CS) cancers.

Materials

Three hundred and fifty-eight lesions that may be changed from category 4 to 5 or vice versa on the basis of the size criterion (category 4: n = 288, category 5: n = 70) from 255 patients were evaluated. Kendall’s tau-b statistic accounting for inter-lesion correlation, generalized estimation equation logistic regression, and receiver operating curve analysis evaluated two lesion size-metrics (lesion diameter and relative lesion diameter—defined as lesion diameter/prostate volume) for ability to identify CS (Gleason grade ≥ 3 + 4) cancer at targeted biopsy. Optimal cut-points were identified using the Youden index. Analyses were performed for the whole prostate (WP) and zone-specific sub-cohorts of lesions in the peripheral and transition zones (PZ and TZ).

Results

Lesion diameter showed a modest correlation with Gleason grade (WP: τB = 0.21, p < 0.0001; PZ: τB = 0.13, p = 0.02; TZ: τB = 0.32, p = 0.001), and association with CS cancer detection (WP: AUC = 0.63, PZ: AUC = 0.59, TZ: AUC = 0.74). Empirically derived thresholds (WP: 14 mm, PZ: 13 mm, TZ: 16 mm) performed similarly to the current ≥ 15 mm standard. Lesion relative lesion diameter improved identification of CS cancers compared to lesion diameter alone (WP: τB = 0.30, PZ: τB = 0.24, TZ: τB = 0.42, all p < 0.0001). AUC also improved for WP and PZ lesions (WP: AUC = 0.70, PZ: AUC = 0.68, and TZ: AUC = 0.74).

Conclusions

The current ≥ 15 mm diameter threshold is a reasonable delineator of PI-RADS category 4 and category 5 lesions in the absence of extraprostatic extension to predict CS cancers. Additionally, relative lesion diameter can improve identification of CS cancers and may serve as another option for distinguishing category 4 and 5 lesions.

  相似文献   
42.
Clinical Rheumatology - To report the clinical characteristics of pulmonary artery involvement (PAI) in patients with Behçet’s syndrome (BS) and to define the predictors of relapses. We...  相似文献   
43.
Uzuner  Selcuk  Durcan  Gizem  Sahin  Sezgin  Bahali  Kayhan  Barut  Kenan  Kilicoglu  Ali Guven  Adrovic  Amra  Bilgic  Ayhan  Kasapcopur  Ozgur 《Clinical rheumatology》2021,40(12):5025-5032
Clinical Rheumatology - Having a child with a chronic illness is a source of stress for the whole family, especially the primary caregiver. The aim of this study was to evaluate the associations...  相似文献   
44.
PurposeBlastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and poor prognostic hematological malignancy. There is still no standard treatment established for BPDCN patients. We aim to summarize the main clinical, biological features and treatment of 9 BPDCN patients.MethodsNine patients with BPDCN who had been diagnosed between July 2008 and December 2018 in Ankara University School of Medicine, were retrospectively evaluated.ResultsAll patients (n = 9) were male, median age was 64 (21–80). Five patients (55.6%) had bone marrow infiltration, 5 patients (55.6%) cutaneous lesions, 6 patients (66.7%) lymph node involvement, 2 patients (22.2%) central nervous system involvement and 2 patients (22.2%) spleen involvement at time of diagnosis. Complex karyotype was observed in 2 patients. CHOP was given to 5 patients (55.6%), hyper-CVAD to 2 patients (22.2%), fludarabine, cyclophosphamide and mitoxantrone to 1 patient (11.1%) and cyclophosphamide, etoposide, methylprednisolone to 1 patient (11.1%) as first line chemotherapy. Four patients (44.4%) underwent allogeneic hematopoietic stem cell transplantation (AHSCT) in complete remission (CR) 1. Venetoclax was given to a transplant ineligible patient who had skin and lymph node involvement, with the off-label use. The median follow-up time was 15.9 months (3–48.6 months). Estimated median overall survival was 15.9 + 1.6 (95% CI 12.7–19.1) months.ConclusionIntensive induction therapies followed by AHSCT in CR seems to be best approaches for patients with BPDCN. Thus, more effective treatment strategies particularly targeted therapies should be warranted to improve the survival of patients with this rare disease.  相似文献   
45.
Pituitary - Our aim was to investigate the changes in the composition of oral and gut microbiota in patients with newly diagnosed acromegaly and their relationship with IGF-1 levels. Oral and fecal...  相似文献   
46.
Purpose

Hypophysitis is a heterogeneous condition that includes inflammation of the pituitary gland and infundibulum, and it can cause symptoms related to mass effects and hormonal deficiencies. We aimed to evaluate the potential role of machine learning methods in differentiating hypophysitis from non-functioning pituitary adenomas.

Methods

The radiomic parameters obtained from T1A-C images were used. Among the radiomic parameters, parameters capable of distinguishing between hypophysitis and non-functioning pituitary adenomas were selected. In order to avoid the effects of confounding factors and to improve the performance of the classifiers, parameters with high correlation with each other were eliminated. Machine learning algorithms were performed with the combination of gray-level run-length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray-level co-occurrence entropy.

Results

A total of 34 patients were included, 17 of whom had hypophysitis and 17 had non-functioning pituitary adenomas. Among the 38 radiomics parameters obtained from post-contrast T1-weighted images, 10 tissue features that could differentiate the lesions were selected. Machine learning algorithms were performed using three selected parameters; gray level run length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray level co-occurrence entropy. Error matrices were calculated by using the machine learning algorithm and it was seen that support vector machines showed the best performance in distinguishing the two lesion types.

Conclusions

Our analysis reported that support vector machines showed the best performance in distinguishing hypophysitis from non-functioning pituitary adenomas, emphasizing the importance of machine learning in differentiating the two lesions.

  相似文献   
47.
Complications of valve replacement are diverse. In addition to morbidity due to the prosthetic valve itself (e.g. endocarditis, thrombosis), complications due to operative technique may occur in complex cases, as in aortic valve replacement with annular enlargement. Postoperative echocardiography is a simple, non-invasive method to evaluate patients with prosthetic valves. Detailed knowledge of the surgical technique employed and of probable complications is necessary to make an accurate diagnosis. The case is reported of a woman with aortic valve replacement and annular enlargement who had mitral regurgitation due to a tear in the anterior mitral leaflet as a complication of Manouguian's annulus enlargement.  相似文献   
48.

Objective

Guidelines have been established for cross‐cultural adaptation of outcome measures. However, invariance across cultures must also be demonstrated through analysis of Differential Item Functioning (DIF). This is tested in the context of a Turkish adaptation of the Health Assessment Questionnaire (HAQ).

Methods

Internal construct validity of the adapted HAQ is assessed by Rasch analysis; reliability, by internal consistency and the intraclass correlation coefficient; external construct validity, by association with impairments and American College of Rheumatology functional stages. Cross‐cultural validity is tested through DIF by comparison with data from the UK version of the HAQ.

Results

The adapted version of the HAQ demonstrated good internal construct validity through fit of the data to the Rasch model (mean item fit 0.205; SD 0.998). Reliability was excellent (α = 0.97) and external construct validity was confirmed by expected associations. DIF for culture was found in only 1 item.

Conclusions

Cross‐cultural validity was found to be sufficient for use in international studies between the UK and Turkey. Future adaptation of instruments should include analysis of DIF at the field testing stage in the adaptation process.
  相似文献   
49.
50.
OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies.  相似文献   
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