Browsing by Author "Roa J.C."

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    Gastrointestinal bleeding due to vascular malformation secondary to mesenteric-gonadal portosystemic shunt in pre-transplant chronic liver disease
    (Springer, 2023) Moya Abuhadba R.; Steffens Venegas E.; Iglesias Bettini A.; Roa J.C.; Besa C.; Espino A.; Larach J.T.; CEDEUS (Chile)
    © The Author(s), under exclusive license to Springer Nature Switzerland AG 2021. All rights reserved.This chapter addresses the study of the validity of high-stakes assessments, such as those used in the admissions to higher education and professional certification. This study requires, as an initial stage, making explicit the uses that will be given to the scores obtained in those instruments. The specification of the uses can be done through the study of the program theory or logic model. The chapter discusses and gives examples of validity studies that examine the most frequent uses for these types of measures: predictive validity studies and the validity of performance standards. It is argued that the adequate use of high-stakes assessments requires measures that do not present irrelevant variance of the construct. Methodologies for those analyses are presented. It is also proposed that the validity argument should not be limited to the empirical verification of the measures intended goals, but it should also include the possible occurrence of unexpected consequences. Some of the most frequent unexpected consequences in the literature are discussed.
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    Intracholecystic tubular non-mucinous neoplasm (ICTN) of the gallbladder: a clinicopathologically distinct, invasion-resistant entity
    (2021) Pehlivanoglu B.; Balci S.; Memis B.; Dursun N.; Saka B.; Reid M.D.; Basturk O.; Bagci P.; Erbarut Seven I.; Jang K.T.; Ohike N.; Tajiri T.; Roa J.C.; Sarmiento J.M.; Adsay V.; Adsay V.
    © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.Preinvasive tumor-forming gallbladder neoplasms that are composed of small, non-mucinous tubules with complex architecture remain a poorly characterized group. Here, we evaluated the clinicopathological characteristics of this entity. Twenty-eight examples were analyzed. Tumors were invariably pedunculated polyps with thin stalks, often presented as loosely attached intraluminal nodules, with cauliflower architecture (akin to cholesterol polyps) comprised of compact, back-to-back acinar-like, small tubular units with minimal/no cytoplasm showing variable complexity, creating a picture distinct from the other tubular type dysplasia in the gallbladder. Their limited stroma showed distinctive amorphous amyloid-like hyalinization (39%). While some had round nuclei with single prominent nucleoli, others exhibited slightly more elongated nuclei with washed out chromatin reminiscent of papillary thyroid carcinoma. Squamoid/meningothelial-like morules (71%) and subtle neuroendocrine cell clusters (39%) were frequent. The level of cytoarchitectural atypia qualified as high-grade dysplasia (HGD) in all cases, but none were invasive. The background mucosa showed no dysplasia, but cholesterolosis. The majority (n = 8/12) showed diffuse MUC6 expression and lacked MUC5AC expression. Based on these observations, 635 gallbladder carcinomas were re-analyzed for residual/adjacent lesions with entity-defining characteristics disclosed here, and none could be identified. Preinvasive tubular non-mucinous neoplasm of the gallbladder, which we propose to classify as intracholecystic tubular non-mucinous neoplasm, is a clinicopathologically discrete entity, which tends to occur in uninjured gallbladders and in association with cholesterol polyps. By being tubular, non-mucinous and MUC6-positive, it is akin to intraductal tubulopapillary neoplasms of pancreatobiliary tract, but it is also different in many other aspects. Although their cytoarchitectural complexity warrants an HGD/carcinoma classification, they do not show invasion and their distinct characteristics warrant their separate classification.
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    ThyroidPrint®: clinical utility for indeterminate thyroid cytology
    (2023) Olmos R.; Dominguez J.M.; Vargas-Salas S.; Mosso L.; Fardella C.E.; Gonzalez G.; Baudrand R.; Guarda F.; Valenzuela F.; Arteaga E.; Forenzano P.; Nilo F.; Lustig N.; Martinez A.; Lopez J.M.; Cruz F.; Loyola S.; Leon A.; Droppelmann N.; Montero P.; Dominguez F.; Camus M.; Solar A.; Zoroquiain P.; Roa J.C.; Munoz E.; Bruce E.; Gajardo R.; Miranda G.; Riquelme F.; Mena N.; Gonzalez H.E.; NCD Risk Factor Collaboration (NCD-RisC)
    Molecular testing contributes to improving the diagnosis of indeterminate thyroid nodules (ITNs). ThyroidPrint® is a ten-gene classifier aimed to rule out malignancy in ITN. Post-validation studies are necessary to determine the real-world clinical benefit of ThyroidPrint® in patients with ITN. A single-center, prospective, noninterventional clinical utility study was performed, analyzing the impact of ThyroidPrint® in the physicians' clinical decisions for ITN. Demographics, nodule characteristics, benign call rates (BCRs), and surgical outcomes were measured. Histopathological data were collected from surgical biopsies of resected nodules. Of 1272 fine-needle aspirations, 109 (8.6%) were Bethesda III and 135 (10.6%) were Bethesda IV. Molecular testing was performed in 155 of 244 ITN (63.5%), of which 104 were classified as benign (BCR of 67.1%). After a median follow-up of 15 months, 103 of 104 (99.0%) patients with a benign ThyroidPrint® remained under surveillance and one patient underwent surgery which was a follicular adenoma. Surgery was performed in all 51 patients with a suspicious for malignancy as per ThyroidPrint® result and in 56 patients who did not undergo testing, with a rate of malignancy of 70.6% and 32.1%, respectively. A higher BCR was observed in follicular lesion of undetermined significance (87%) compared to atypia of undetermined significance (58%) (P < 0.05). False-positive cases included four benign follicular nodules and six follicular and four oncocytic adenomas. Our results show that, physicians chose active surveillance instead of diagnostic surgery in all patients with a benign ThyroidPrint® result, reducing the need for diagnostic surgery in 67% of patients with preoperative diagnosis of ITN.