Araştırma Çıktıları
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Item 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, BarisOBJECTIVE. 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.Item Conspicuity of Peripheral Zone Prostate Cancer on Computed Diffusion-Weighted Imaging: Comparison of cDWI(1500), cDWI(2000), and cDWI(3000)(HINDAWI LTD, 2014-01-01) Vural, Metin; Ertas, Gokhan; Onay, Aslihan; Acar, Omer; Esen, Tarik; Saglican, Yesim; Zengingonul, Hale Pinar; Akpek, SerginIntroduction and Objective. Disadvantages associated with direct high b-value measurements may be avoided with use of computed diffusion-weighted imaging (cDWI). The purpose of this study is to assess the diagnostic performance of cDWI image sets calculated for high b-values of 1500, 2000, and 3000 s/mm(2). Materials and Methods. Twenty-eight patients who underwent multiparametric MRI of the prostate and radical prostatectomy consecutively were enrolled in this retrospective study. Using a software developed at our institute, cDWI 1500, cDWI 2000, and cDWI 3000 image sets were generated by fitting a monoexponential model. Index lesions on cDWI image sets were scored by two radiologists in consensus considering lesion conspicuity, suppression of background prostate tissue, distortion, image set preferability, and contrast ratio measurements were performed. Results. Lesion detection rates are the same for computed b-values of 2000 and 3000 s/ mm 2 and are better than b-values of 1500 s/ mm(2). Best lesion conspicuity and best background prostate tissue suppression are provided by cDWI(3000) image set. cDWI(2000) image set provides the best zonal anatomical delineation and less distortion and was chosen as the most preferred image set. Average contrast ratio measured on these image sets shows almost a linear relation with the b-values. Conclusion. cDWI 2000 image set with similar conspicuity and the same lesion detection rate, but better zonal anatomical delineation, and less distortion, was chosen as the preferable image set.Item Multiparametric MRI guidance in first-time prostate biopsies: what is the real benefit?(TURKISH SOC RADIOLOGY, 2015-01-01) Acar, Omer; Esen, Tarik; Colakoglu, Bulent; Vural, Metin; Onay, Aslihan; Saglican, Yesim; Tuerkbey, Baris; Rozanes, IzzetPURPOSE With the increased recognition of the capabilities of prostate multiparametric (mp) magnetic resonance imaging (MRI), attempts are being made to incorporate MRI into routine prostate biopsies. In this study, we aimed to analyze the diagnostic yield via cognitive fusion, transrectal ultrasound (TRUS)-guided, and in-bore MRI-guided biopsies in biopsy-naive patients with positive findings for prostate cancer screening. METHODS Charts of 140 patients, who underwent transrectal prostate biopsy after the adaptation of mp-MRI into our routine clinical practice, were reviewed retrospectively. Patients with previous negative biopsies (n=24) and digital rectal examination findings suspicious for >= cT3 prostate cancer (n=16) were excluded. T2-weighted imaging, diffusion-weighted imaging, and dynamic contrast-enhanced imaging were included in mp-MRI. Cognitive fusion biopsies were performed after a review of mp-MRI data, whereas TRUS-guided biopsies were performed blinded to MRI information. In-bore biopsies were conducted by means of real-time targeting under MRI guidance. RESULTS Between January 2012 and February 2014, a total of 100 patients fulfilling the inclusion criteria underwent TRUS-guided (n=37), cognitive fusion (n=49), and in-bore (n=14) biopsies. Mean age, serum prostate specific antigen level, and prostate size did not differ significantly among the study groups. In TRUS-guided biopsy group, 51.3\% were diagnosed with prostate cancer, while the same ratio was 55.1\% and 71.4\% in cognitive fusion and in-bore biopsy groups, respectively (P = 0.429). Clinically significant prostate cancer detection rate was 69.1\%, 70.3\%, and 90\% in TRUS-guided, cognitive fusion, and in-bore biopsy groups, respectively (P = 0.31). According to histopathologic variables in the prostatectomy specimen, significant prostate cancer was detected in 85.7\%, 93.3\%, and 100\% of patients in TRUS-guided, cognitive fusion, and in-bore biopsy groups, respectively. CONCLUSION In the first set of transrectal prostate biopsies, mp-MRI guidance did not increase the diagnostic yield significantly.Item Evaluation of Peripheral Zone Prostate Cancer Aggressiveness Using the Ratio of Diffusion Tensor Imaging Measures(WILEY-HINDAWI, 2017-01-01) Onay, Aslihan; Ertas, Gokhan; Vural, Metin; Acar, Omer; Saglican, Yesim; Coskun, Bilgen; Akpek, SerginPurpose. To evaluate the aggressiveness of peripheral zone prostate cancer by correlating the Gleason score (GS) with the ratio of the diffusion tensor imaging (DTI) measures. Materials and Methods. Forty-two peripheral zone prostate tumors were imaged using DTI. Regions of interest focusing on the center of tumor foci and noncancerous tissue were used to extract statistical measures of mean diffusivity (MD) and fractional anisotroy (FA). Measure ratio was calculated by dividing tumor measure by noncancerous tissue measure. Results. Strong correlations are observable between GS and MD measures while weak correlations are present between GS and FA measures. Minimum tumor MD (MDmin) and the ratio of minimum MD (rMD(min)) show the same highest correlation with GS (both rho = -0.73). Between GS <= 7 (3 + 4) and GS >= 7 (4 + 3), differences are significant for all MD measures but for some FA measures. MD measures perform better than FA measures in discriminating GS >= 7 (4 + 3). Conclusion. Ratios of MD measures can be used in evaluation of peripheral zone prostate cancer aggressivenessItem Comparison of the trifecta outcomes of robotic and open nephron-sparing surgeries performed in the robotic era of a single institution (vol 4, 472, 2015)(SPRINGER INTERNATIONAL PUBLISHING AG, 2015-01-01) Acar, Omer; Ozturk-Isik, Esin; Mut, Tuna; Saglican, Yesim; Onay, Aslihan; Vural, Metin; Musaoglu, Ahmet; Esen, TarikItem Non-muscle invasive bladder cancer tissues have increased base excision repair capacity(NATURE PORTFOLIO, 2020-01-01) Somuncu, Berna; Keskin, Selcuk; Antmen, Fatma Merve; Saglican, Yesim; Ekmekcioglu, Aysegul; Ertuzun, Tugce; Tuna, Mustafa Bilal; Obek, Can; Wilson, David M.; Ince, Umit; Kural, Ali Riza; Muftuoglu, MeltemThe molecular mechanisms underlying the development and progression of bladder cancer (BC) are complex and have not been fully elucidated. Alterations in base excision repair (BER) capacity, one of several DNA repair mechanisms assigned to preserving genome integrity, have been reported to influence cancer susceptibility, recurrence, and progression, as well as responses to chemotherapy and radiotherapy. We report herein that non-muscle invasive BC (NMIBC) tissues exhibit increased uracil incision, abasic endonuclease and gap-filling activities, as well as total BER capacity in comparison to normal bladder tissue from the same patient (p<0.05). No significant difference was detected in 8-oxoG incision activity between cancer and normal tissues. NMIBC tissues have elevated protein levels of uracil DNA glycosylase, 8-oxoguanine DNA glycosylase, AP endonuclease 1 and DNA polymerase beta protein. Moreover, the fold increase in total BER and the individual BER enzyme activities were greater in high-grade tissues than in low-grade NMIBC tissues. These findings suggest that enhanced BER activity may play a role in the etiology of NMIBC and that BER proteins could serve as biomarkers in disease prognosis, progression or response to genotoxic therapeutics, such as Bacillus Calmette-Guerin.Item Comparison of the trifecta outcomes of robotic and open nephron-sparing surgeries performed in the robotic era of a single institution(SPRINGER INTERNATIONAL PUBLISHING AG, 2015-01-01) Acar, Omer; Isik, Esin Ozturk; Mut, Tuna; Saglican, Yesim; Onay, Aslihan; Vural, Metin; Musaoglu, Ahmet; Esen, TarikPurpose: In this study we aimed to report a comparative analysis between open and robotic nephron sparing surgeries (NSS) from a single institutional database. Methods: Patients who have undergone NSS during the robotic era of our institution were included in this study. Open (n = 74) and robotic (n = 59) groups were compared regarding trifecta outcome. Trifecta was defined asItem Association of B7-H4 gene polymorphisms in urothelial bladder cancer(TUBITAK SCIENTIFIC \& TECHNICAL RESEARCH COUNCIL TURKEY, 2017-01-01) Ozgoz, Asuman; Samli, Murat; Dincel, Deniz; Sahin, Ahmet; Ince, Umit; Saglican, Yesim; Balci, Faruk; Samli, HaleBackground/aim: We aimed to study polymorphisms of the B7-H4 gene in order to evaluate a possible association in urothelial carcinoma, as it is highly expressed in cancer tissues. Materials and methods: In this study B7-H4 gene rs10754339, rs10801935, and rs3738414 SNPs were studied by PCR-RFLP method in paraffin-embedded tumor specimens from 62 urothelial carcinoma patients and in a control group including 30 patients without bladder cancer. Results: We detected that the rs10754339 polymorphism was more frequent in the cancer patients when compared with the control group (P < 0.05). Only the rs3738414 polymorphism showed a statistically significant difference in frequency between pathologic diagnostic groups. Conclusion: The rs10754339 AA genotype distribution was found to have a higher frequency whereas the rs3738414 AG genotype distribution was lower in the bladder cancer group (P < 0.05). None of the genotype distributions showed a significant difference from the control group for the rs10801935 polymorphism. We conclude that B7-H4 has the potential to be a useful prognostic marker in urothelial carcinoma.Item Isolated omental metastasis of renal cell carcinoma after extraperitoneal open partial nephrectomy: A case report(ELSEVIER SCI LTD, 2016-01-01) Acar, Omer; Mut, Tuna; Saglican, Yesim; Sag, Alan Alper; Falay, Okan; Selcukbiricik, Fatih; Tabak, Levent; Esen, TarikINTRODUCTION: Metachronous metastatic spread of clinically localized renal cell carcinoma (RCC) affects almost 1/3 of the patients. They occur most frequently in lung, liver, bone and brain. Isolated omental metastasis of RCC has not been reported so far. CASE PRESENTATION: A 62-year-old patient previously diagnosed and treated due to pulmonary sarcoidosis has developed an omental metastatic lesion 13 years after having undergone open extraperitoneal partial nephrectomy for T1 clear-cell RCC. Constitutional symptoms and imaging findings that were attributed to the presence of a sarcomatoid paraneoplastic syndrome triggered by the development this metastatic focus complicated the diagnostic work-up. Biopsy of the {[}18F]-fluorodeoxyglucose (+) lesions confirmed the diagnosis of metastatic RCC and the patient was managed by the resection of the omental mass via near-total omentectomy followed by targeted therapy with a tyrosine kinase inhibitor. DISCUSSION: Late recurrence of RCC has been reported to occur in 10-20\% of the patients within 20 years. Therefore lifelong follow up of RCC has been advocated by some authors. Diffuse peritoneal metastases have been reported in certain RCC subtypes with adverse histopathological features. However, isolated omental metastasis without any sign of peritoneal involvement is an extremely rare condition. CONCLUSION: To our knowledge, this is the first reported case of metachronously developed, isolated omental metastasis of an initially T1 clear-cell RCC. Constitutional symptoms, despite a long interval since nephrectomy, should raise the possibility of a paraneoplastic syndrome being associated with metastatic RCC. Morphological and molecular imaging studies together with histopathological documentation will be diagnostic. (C) 2016 The Authors. Published by Elsevier Ltd. on behalf of IJS Publishing Group Ltd.Item Bilateral renal cell carcinoma with leiomyomatous stroma: A rare entity diagnosed synchronously and treated surgically in a staged fashion(AVES, 2017-01-01) Kiremit, Murat Can; Acar, Omer; Saglican, Yesim; Esen, TarikRenal cell carcinoma (RCC) accounts for approximately 3\% of adult malignancies and 90-95\% of kidney neoplasms. Renal cell carcinoma with leiomyomatous stroma (RCCLS) is an extremely rare histopathological entity based on available literature data. Herein, we report a 31-year-old male with incidentally detected synchronous bilateral renal masses who was eventually found to harbor RCCLS after being operated sequentially via nephron-sparing surgery.