Araştırma Çıktıları

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    Multicenter Multireader Evaluation of an Artificial Intelligence-Based Attention Mapping System for the Detection of Prostate Cancer With Multiparametric MRI
    (AMER ROENTGEN RAY SOC, 2020-01-01) Mehralivand, Sherif; Harmon, Stephanie A.; Shih, Joanna H.; Smith, Clayton P.; Lay, Nathan; Argun, Burak; Bednarova, Sandra; Baroni, Ronaldo Hueb; Canda, Abdullah Erdem; Ercan, Karabekir; Girometti, Rossano; Karaarslan, Ercan; Kural, Ali Riza; Pursyko, Andrei S.; Rais-Bahrami, Soroush; Tonso, Victor Martins; Magi-Galluzzi, Cristina; Gordetsky, Jennifer B.; Silvestre e Silva Macarenco, Ricardo; Merino, Maria J.; Gumuskaya, Berrak; Saglican, Yesim; Sioletic, Stefano; Warren, Anne Y.; Barrett, Tristan; Bittencourt, Leonardo; Coskun, Mehmet; Knauss, Chris; Law, Yan Mee; Malayeri, Ashkan A.; Margolis, Daniel J.; Marko, Jamie; Yakar, Derya; Wood, Bradford J.; Pinto, Peter A.; Choyke, Peter L.; Summers, Ronald M.; Turkbey, Baris
    OBJECTIVE. The purpose of this study was to evaluate in a multicenter dataset the performance of an artificial intelligence (AI) detection system with attention mapping compared with multiparametric MRI (mpMRI) interpretation in the detection of prostate cancer. MATERIALS AND METHODS. MRI examinations from five institutions were included in this study and were evaluated by nine readers. In the first round, readers evaluated mpMRI studies using the Prostate Imaging Reporting and Data System version 2. After 4 weeks, images were again presented to readers along with the AI-based detection system output. Readers accepted or rejected lesions within four AI-generated attention map boxes. Additional lesions outside of boxes were excluded from detection and categorization. The performances of readers using the mpMRI-only and AI-assisted approaches were compared. RESULTS. The study population included 152 case patients and 84 control patients with 274 pathologically proven cancer lesions. The lesion-based AUC was 74.9\% for MRI and 77.5\% for AI with no significant difference (p = 0.095). The sensitivity for overall detection of cancer lesions was higher for AI than for mpMRI but did not reach statistical significance (57.4\% vs 53.6\%, p = 0.073). However, for transition zone lesions, sensitivity was higher for AI than for MRI (61.8\% vs 50.8\%, p = 0.001). Reading time was longer for AI than for MRI (4.66 vs 4.03 minutes, p < 0.001). There was moderate interreader agreement for AI and MRI with no significant difference (58.7\% vs 58.5\%, p = 0.966). CONCLUSION. Overall sensitivity was only minimally improved by use of the AI system. Significant improvement was achieved, however, in the detection of transition zone lesions with use of the AI system at the cost of a mean of 40 seconds of additional reading time.
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    Can SUVmax values of Ga-68-PSMA PET/CT scan predict the clinically significant prostate cancer?
    (LIPPINCOTT WILLIAMS \& WILKINS, 2019-01-01) Demirci, Emre; Kabasakal, Levent; Sahin, Onur E.; Akgun, Elife; Gultekin, Mehmet Hamza; Doganca, Tunkut; Tuna, Mustafa B.; Obek, Can; Kilic, Mert; Esen, Tarik; Kural, Ali R.
    Purpose The intensity of prostate-specific membrane antigen (PSMA) expression increases as the tumor grade increases and the uptake of Ga-68-PSMA is higher in high-grade tumors. The aim of the present study was to evaluate the correlation of preoperative tracer uptake of primary tumor to Gleason Score in patients who underwent prostatectomy. Patients and methods We retrospectively evaluated 141 patients who had Ga-68-PSMA positron emission tomography/computed tomography (PET/CT) imaging and who underwent prostatectomy. All patients had a diagnosis of prostate cancer on the basis of 10-24 cores transrectal ultrasound-guided biopsy (TRUS-Bx). Histological assessment was performed according to the New Contemporary Prostate Cancer Grading System. All patients had a prostate-specific antigen (PSA) level measurement within maximum of 28 days before Ga-68-PSMA PET/CT. Region of interests were drawn manually around the prostate gland, avoiding the bladder activity, to calculate the maximum standardized uptake values (SUVmax) values. Results The median PSA values for all patients were 10.0 ng/ml. PSA values for low-risk patients were significantly lower than those of high-risk patients (P<0.001). There were 41.1\% upgrades and 7.8\% downgrades following prostatectomy in terms of Grade Groups. According to the final pathology reports, 21\% (n=16) of patients moved from a low-risk level (grade groups 1+2) to a high-risk level (grade groups 3+4+5). The median SUVmax value was 8.8, ranging from 2.1 to 62.4. There was a strong correlation between SUVmax values and grade groups (Pearson rho=0.66) (P<0.001). The mean SUVmax values of high-risk patients were significantly higher than those of low-risk patients (18.9 +/- 12.1 vs. 7.16 +/- 6.2, respectively) (P<0.001). Receiver operation characteristic curve analysis of SUVmax at the cut-off value of 9.1 showed a high sensitivity (78\%) and specificity (81\%) for detection of high risk disease. Conclusion SUVmax values correlate significantly with the grade groups of the primary tumor. The intraprostatic accumulation sites may predict clinically significant cancer and potentially serve as a target for biopsy sampling in conjunction with mpMRI in selected patients.
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    A Comparative Study of Multiparametric MRI Sequences in Measuring Prostate Cancer Index Lesion Volume
    (UBIQUITY PRESS LTD, 2022-01-01) Bagcilar, Omer; Alis, Deniz; Seker, Mustafa; Erdemli, Servet; Karaarslan, Umut; Kus, Aylin; Kayhan, Cavit; Saglican, Yesim; Kural, Ali; Karaarslan, Ercan
    Objectives: To compare the effectiveness of individual multiparametric prostate MRI (mpMRI) sequences-T2W, diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC), and dynamic contrast-enhanced (DCE)-in assessing prostate cancer (PCa) index lesion volume using whole-mount pathology as the ground-truth
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    Findings of Gynecomastia That Developed in Follow-up Secondary to Bicalutamide Treatment on Bone Scan
    (GALENOS YAYINCILIK, 2020-01-01) Unal, Kemal; Gokcora, Nahide
    Prostate cancer is a common neoplastic disease especially in elder patients. Metastatic prostate disease has low five-year survival rate. Bicalutamide is an androgen receptor antagonist that acts as an inhibitor by competizing androgen receptors in the target tissue and used as a treatment option in prostate cancer. Bone scan was performed on a 79-year-old male with prostate cancer in our department. Blood pool images showed bilateral hyperemia in the breast regions which was not present on the previous scan one year ago. On physical examination, there was bilateral painful gynecomastia. It was learned that the patient was given Bicalutamide therapy after the first bone scan. Blood pool images may detect this side effect and should be evaluated with physical examination in case of clinical doubt.
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    Can We Accomplish Better Oncological Results with Robot-Assisted Radical Prostatectomy?
    (MARY ANN LIEBERT, INC, 2017-01-01) Kural, Ali Riza; Obek, Can; Doganca, Tunkut
    Surgical removal with radical prostatectomy has been a cornerstone for the treatment of prostate cancer and is associated with level 1 evidence for survival advantage compared with watchful waiting. Since the first structured robotic program was launched in 2000, robot-assisted radical prostatectomy (RARP) has had a rapid diffusion and surpassed its open radical prostatectomy (ORP) and laparoscopic radical prostatectomy (LRP) counterparts in the United States and is progressively expanding in other countries. Interestingly, this common acceptance of RARP was initially driven in the paucity of robust clinical evidence. There is still lack of level 1 evidence with prospective randomized trials on the oncologic outcomes of RARP. In that scenario, the clinician has to rely on retrospective data and systemic and meta-analyses. In comparison with ORP and LRP, RARP has proven to reach at least equivalent oncological outcomes. Lower rate of positive surgical margins may probably be achieved with RARP in pT2 patients. Although urologists were initially reluctant to embrace RARP in highrisk patients and lymph node yield was low, contemporary series have revealed that RARP and extended lymphadenectomy may be safely performed with obtaining similar (or better) nodal yields compared with ORP. Surgeon experience is universally of utmost importance in obtaining good outcomes. We will need to wait for long-term results of contemporary series to comprehend the impact of RARP on cancer-specific survival and overall survival. Using novel imaging before surgery and frozen section analysis during surgery may allow for superior oncological outcomes.
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    The utility of ADC parameters in the diagnosis of clinically significant prostate cancer by 3.0-Tesla diffusion-weighted magnetic resonance imaging
    (INT SCIENTIFIC INFORMATION INC, 2021-01-01) Kus, Aylin Altan
    Purpose: This study has focused on investigating the relationship between the exponential apparent diffusion coefficient (exp-ADC), selective apparent diffusion coefficient (sel-ADC) values, the ADC ratio (ADCr), and prostate cancer aggressiveness with transrectal ultrasound-guided prostate biopsy in patients with prostate cancer. Material and methods: All patients underwent a multiparametric magnetic resonance imaging (mpMRI) including tri-planar T2-weighted (T2W), dynamic contrast-enhanced (DCE), diffusion-weighted sequences using a 3.0-Tesla MR scanner (Skyra, Siemens Medical Systems, Germany) with a dedicated 18-channel body coil and a spine coil underneath the pelvis, with the patient in the supine position. Exp-ADC, sel-ADC, and ADCr of defined lesions were evaluated using region-of-interest-based measurements. Exp-ADC, sel-ADC, and ADCr were correlated with the Gleason score obtained through transrectal ultrasound-guided biopsy. Results: Patients were divided into 2 groups. Group I is Gleason score >= 3 + 4, group II is Gleason score = 6. Sel-ADC and exp-ADC were statistically significant between 2 groups (0.014 and 0.012, respectively). However, the ADCr difference between nonclinical significant prostate cancer from clinically significant prostate cancer was not significant (p = 0.09). Conclusions: This study is the first to evaluate exp-ADC and sel-ADC values of prostate carcinoma with ADCr. One limitation of this study might be the limited number of patients. Exp-ADC and sel-ADC values in prostate MRI imaging improved the specificity, accuracy, and area under the curve (AUC) for detecting clinically relevant prostate carcinoma. Adding exp-ADC and sel-ADC values to ADCr can be used to increase the diagnostic accuracy of DWI.