Yazar "Dursun, Nevra" seçeneğine göre listele
Listeleniyor 1 - 7 / 7
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Calculation of the Ki67 index in pancreatic neuroendocrine tumors: A comparative analysis of four counting methodologies(Nature Publishing Group, 2015) Reid, Michelle Dian; Bağcı, Pelin; Ohike, Nobuyuki; Saka, Burcu; Erbarut Seven, İpek; Dursun, Nevra; Balcı, Serdar; Gucer, Hasan; Jang, Kee-Taek; Tajiri, Takuma; Baştürk, Olca; Kong, So Yeon; Goodman, Michael; Akkaş, Gizem; Adsay, VolkanKi67 index is now an essential part of classification of pancreatic neuroendocrine tumors. However, its adaptation into daily practice has been fraught with challenges related to counting methodology. In this study, three reviewers used four counting methodologies to calculate Ki67 index in 68 well-differentiated pancreatic neuroendocrine tumors: (1) 'eye-ball' estimation, which has been advocated as reliable and is widely used; (2) automated counting by image analyzer; (3) manual eye-counting (eye under a microscope without a grid); and (4) manual count of camera-captured/printed image. Pearson's correlation (R) was used to measure pair-wise correlation among three reviewers using all four methodologies. Average level of agreement was calculated using mean of R values. The results showed that: (1) 'eye-balling' was least expensive and fastest (average time <1 min) but had poor reliability and reproducibility. (2) Automated count was the most expensive and least practical with major impact on turnaround time (limited by machine and personnel accessibility), and, more importantly, had inaccuracies in overcounting unwanted material. (3) Manual eye count had no additional cost, averaged 6 min, but proved impractical and poorly reproducible. (4) Camera-captured/printed image was most reliable, had highest reproducibility, but took longer than 'eye-balling'. In conclusion, based on its comparatively low cost/benefit ratio and reproducibility, camera-captured/printed image appears to be the most practical for calculating Ki67 index. Although automated counting is generally advertised as the gold standard for index calculation, in this study it was not as accurate or cost-effective as camera-captured/printed image and was highly operator-dependent. 'Eye-balling' produces highly inaccurate and unreliable results, and is not recommended for routine use.Öğe Can the use of reference pictures improve the interobserver variability on assessment of liver steatosis percentage: A digital platform based approach(Springer, 2017) Türkmen Çetinaslan, İlknur; Çakır, Aslı; Çapar, Aslı Gizem; Saka, Burcu; Kahraman, Zuhal; Erkan, Sengiz; Özkan, Yücel; Kepil, Nuray; Keser, Sevinç Hallaç; Güçin, Zuhal; Ceyran, Bahar; Çoban, Ganime; Yılmaz Seğmen, Müberra; Arıcı, Sema; Dursun, Nevra; Doğusoy, Gülen Bülbül; Tuncel, Dilek; Özgüven Yılmaz, Banu; Paşaoğlu, Esra; Kamalı Harman, Gülçin; Kırımlıoğlu, Hale; Erdamar, Sibel; Yıldız, Şemsi; Erdoğan Yıldırım, Nilsen; Armutlu, Ayşe[Abstract Not Available]Öğe Field risk ("field-effect"/"field-defect") in the gallbladder and biliary tree: An under-recognized phenomenon with major implications for management and carcinogenesis(Nature Publishing Group, 2019) Reid, Michelle; Losada, Hector; Muraki, Takashi; Pehlivanoğlu, Burçin; Memiş, Bahar; Koshiol, Jill; Bağcı, Pelin; Seven, İpek Erbarut; Balcı, Serdar; Saka, Burcu; Dursun, Nevra; Jang, Keetaek; Ohike, Nobuyuki; Tajiri, Takuma; Goodman, Michael; Carlos Roa, Juan; Araya, Juan; Bellolio, Enrique; Sarmiento, Juan; Xue, Yue; Baştürk, Olca; Adsay, Volkan[Abstract Not Available]Öğe Field risk ("field-effect"/"field-defect") in the gallbladder and biliary tree: An under-recognized phenomenon with major implications for management and carcinogenesis(Nature Publishing Group, 2019) Reid, Michelle; Losada, Hector; Muraki, Takashi; Pehlivanoğlu, Burçin; Memiş, Bahar; Koshiol, Jill; Bağcı, Pelin; Seven, İpek Erbarut; Balcı, Serdar; Saka, Burcu; Dursun, Nevra; Jang, Keetaek; Ohike, Nobuyuki; Tajiri, Takuma; Goodman, Michael; Carlos Roa, Juan; Araya, Juan; Bellolio, Enrique; Sarmiento, Juan; Xue, Yue; Baştürk, Olca; Adsay, Volkan[Abstract Not Available]Öğe Follicular cholecystitis: Reappraisal of incidence, definition, and clinicopathologic associations in an analysis of 2550 cholecystectomies(SAGE Publications Inc, 2020) Saka, Burcu; Memiş, Bahar; Erbarut Seven, İpek; Pehlivanoğlu, Burçin; Balcı, Serdar; Bağcı, Pelin; Reid, Michelle; Dursun, Nevra; Tapia Escalano, Oscar; Carlos Roa, Juan; Carlos Araya, Juan; Kong, So Yeon; Baştürk, Olca; Koshiol, Jill; Adsay, N. VolkanContext.Follicular cholecystitis (FC) is a poorly characterized entity.Objective.To determine its frequency/clinicopathologic associations.Design.A total of 2550 cholecystectomy specimens were examined. Two hundred three of these were consecutive routine cholecystectomies submitted entirely for microscopic examination to determine the relative frequency of incidental pathologies in gallbladders (GBs). The remainder had representative sampling. Underlying conditions were nonobstructive pathologies (1270 nonspecific cholecystitis), obstructive (62 distal biliary tract tumors, 35 primary sclerosing cholangitis, and 31 autoimmune pancreatitis), and neoplastic (n = 949). FC was defined as 3 distinct lymphoid follicles (LFs)/centimeter.Results.In the GBs totally submitted for microscopic examination, the true frequency of FC was found to be 2.5% (5/203), and in the representatively sampled group, it was 1.9%, with similar frequencies in nonobstructive, obstructive, and neoplastic cases (2.3%, 3.1%, and 1.3%, respectively, P = .77). When the 39 FC in nonneoplastic GBs contrasted with ordinary chronic cholecystitis, they were associated with older age (68 vs 49 years, P < .0001), similar gallstone frequency (68 vs 81%), female/male ratio (2.7 vs 2.6), and wall thickness (4 mm for both). None had lymphoma/parasites/Salmonella infection. Of 17 cases who had undergone gastric biopsy, 5 had chronic gastritis (2 with Helicobacter pylori). Microscopically, the LFs were the main inflammatory process often with minimal intervening inflammation. IgG4-positive plasma cell density was low (<10/high-power field) in 21/24(87.5%) cases.Conclusions.Follicular cholecystitis is seen in 2% of cholecystectomies, typically in significantly older patients, suggesting a deranged immune response. A third of the patients reveal biopsy-proven gastritis. FC does not seem to be associated with autoimmunity, lymphoma, or obstructive pathologies.Öğe Gallbladder polyps: Correlation of size and clinicopathologic characteristics based on updated definitions(Public Library of Science, 2020) Taşkın, Orhun C.; Baştürk, Olca; Reid, Michelle D.; Dursun, Nevra; Bağcı, Pelin; Saka, Burcu; Balcı, Serdar; Memiş, Bahar; Bellolio, Enrique; Araya, Juan Carlos; Roa, Juan Carlos; Tapia, Oscar; Losada, Hector; Sarmiento, Juan; Jang, Kee-Taek; Jang, Jin-Young; Pehlivanoğlu, Burçin; Erkan, Mert; Adsay, VolkanBackground Different perspectives exist regarding the clinicopathologic characteristics, biology and management of gallbladder polyps. Size is often used as the surrogate evidence of polyp behavior and size of >= 1cm is widely used as cholecystectomy indication. Most studies on this issue are based on the pathologic correlation of polyps clinically selected for resection, whereas, the data regarding the nature of polypoid lesions from pathology perspective -regardless of the cholecystectomy indication- is highly limited. Methods In this study, 4231 gallbladders -606 of which had gallbladder carcinoma- were reviewed carefully pathologically by the authors for polyps (defined as >= 2 mm). Separately, the cases that were diagnosed as "gallbladder polyps" in the surgical pathology databases were retrieved. Results 643 polyps identified accordingly were re-evaluated histopathologically. Mean age of all patients was 55 years (range: 20-94); mean polyp size was 9 mm. Among these 643 polyps, 223 (34.6%) were neoplastic: I. Non-neoplastic polyps (n = 420; 65.4%) were smaller (mean: 4.1 mm), occurred in younger patients (mean: 52 years). This group consisted of fibromyoglandular polyps (n = 196) per the updated classification, cholesterol polyps (n = 166), polypoid pyloric gland metaplasia (n = 41) and inflammatory polyps (n = 17). II. Neoplastic polyps were larger (mean: 21 mm), detected in older patients (mean: 61 years) and consisted of intra-cholecystic neoplasms (WHO's "adenomas" and "intracholecystic papillary neoplasms", >= 1 cm; n = 120), their "incipient" version (<1 cm) (n = 44), polypoid invasive carcinomas (n = 26) and non-neoplastic polyps with incidental dysplastic changes (n = 33). In terms of size cut-off correlations, overall, only 27% of polyps were >= 1 cm, 90% of which were neoplastic. All (except for one) >= 2 cm were neoplastic. However, 14% of polyps <1 cm were also neoplastic. Positive predictive value of >= 1 cm cut-off -which is widely used for cholecystectomy indication-, was 94.3% and negative predictive value was 85%. Conclusions Approximately a third of polypoid lesions in the cholecystectomies (regardless of the indication) prove to be neoplastic. The vast majority of (90%) of polyps >= 1 cm and virtually all of those >= 2 cm are neoplastic confirming the current impression that polyps >= 1 cm ought to be removed. However, this study also illustrates that 30% of the neoplastic polyps are <1 cm and therefore small polyps should also be closely watched, especially in older patients.Öğe Non-neoplastic polyps of the gallbladder: A clinicopathologic analysis of 447 cases(2020) Taşkın, Orhun; Bellolio, Enrique; Dursun, Nevra; Erbarut Seven, İpek; Roa, Juan C.; Araya, Juan C.; Villaseca, Miguel; Tapia, Oscar; Vance, Courtney; Saka, Burcu; Balcı, Serdar; Bağcı, Pelin; Losada, Hector; Sarmiento, Juan; Memis, Bahar; Pehlivanoğlu, Burçin; Baştürk, Olca; Reid, Michelle D.; Koshiol, Jill; Cheng, Jeanette; Kapran, Yersu; Adsay, VolkanThere is no systematic histopathologic analysis of non-neoplastic polyps in the gallbladder. In this study, in addition to a computer search for cases designated as "polyp," a systematic review of 2533 consecutive routinely sampled archival and 203 totally submitted prospective cholecystectomies were analyzed for >2?mm polyps (cut-off was based on radiologic sensitivity). A total of 447 non-neoplastic polyps were identified. The frequency was 3% in archival cases and 5% in totally submitted cases. Only 21 (5%) were ?1?cm. The average age was 52 years, and the female to male ratio was 3.1. Two distinct categories were delineated: (1) injury-related polyps (n=273): (a) Fibro(myo)glandular polyps (n=214) were small (mean=0.4?cm), broad-based, often multiple (45%), almost always (98%) gallstone-associated, and were composed of a mixture of (myo)fibroblastic tissue/lobular glandular units with chronic cholecystitis. Dysplasia seen in 9% seemed to be secondary involvement. (b) Metaplastic pyloric glands forming polypoid collections (n=42). (c) Inflammatory-type polyps associated with acute/subacute injury (11 granulation tissue, 3 xanthogranulomatous, 3 lymphoid). (2) Cholesterol polyps (n=174) occurred in uninjured gallbladders, revealing a very thin stalk, edematous cores devoid of glands but with cholesterol-laden macrophages in 85%, and cholesterolosis in the uninvolved mucosa in 60%. Focal low-grade dysplasia was seen in 3%, always confined to the polyp, unaccompanied by carcinoma. In conclusion, non-neoplastic polyps are seen in 3% of cholecystectomies and are often small. Injury-related fibromyoglandular polyps are the most common. Cholesterol polyps have distinctive cauliflower architecture, often in a background of uninjured gallbladders with cholesterolosis and may lack the cholesterol-laden macrophages in the polyp itself. Although dysplastic changes can involve non-neoplastic polyps, they do not seem to be the cause of invasive carcinoma by themselves.
