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We examine the connection between firm performance and a CEO's previous position (inside or outside the firm), using Covid-19 as an exogenous shock. Firms led by insider CEOs outperformed those led by outsider CEOs in terms of return on assets during the Covid-19 crisis period in 2020, but there was no performance differential in the period before the crisis. Additional tests indicate that outperformance under insider CEOs is observed in firms holding more cash and firms with a higher proportion of internally promoted non-CEO executives. These findings have important implications for boards of directors making CEO appointments.
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Ultrasonography (US) is a useful diagnostic modality for evaluation of the size and features of thyroid nodules. Tumor size is a key indicator of the surgical extent of thyroid cancer. We evaluated the difference in tumor sizes measured by preoperative US and postoperative pathologic examination in papillary thyroid carcinoma (PTC). We reviewed the medical records of 172 consecutive patients, who underwent thyroidectomy for PTC treatment. We compared tumor size, as measured by preoperative US, with that in postoperative specimens. And we analyzed a number of factors potentially influencing the size measurement, including cancer size, calcification and coexisting thyroiditis. The mean size of the tumor measured by preoperative US was 11.4, and 10.2 mm by postoperative pathologic examination. The mean percentage difference (US-pathology/US) of tumor sizes measured by preoperative US and postoperative pathologic examination was 9.9 ± 19.3%, which was statistically significant (p < 0.001). When the effect of tumor size (≤10.0 vs. 10.1-20.0 vs. >20.0 mm) and the presence of calcification or coexisting thyroiditis on the tumor size discrepancy between the two measurements was analyzed, the mean percentage differences according to tumor size (9.1 vs. 11.2% vs. 9.8%, p = 0.842), calcification (9.2 vs. 10.2%, p = 0.756) and coexisting thyroiditis (17.6 vs. 9.5%, p = 0.223) did not show statistical significance. Tumor sizes measured in postoperative pathology were ~90% of those measured by preoperative US in PTC; this was not affected by tumor size, the presence of calcification or coexisting thyroiditis. When the surgical extent of PTC treatment according to tumor size measured by US is determined, the relative difference between tumor sizes measured by preoperative US and postoperative pathologic examination should be considered.
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Carcinoma Papilar/diagnóstico por imagen , Neoplasias de la Tiroides/diagnóstico por imagen , Carga Tumoral/fisiología , Adolescente , Adulto , Anciano , Biopsia con Aguja Fina , Calcinosis/diagnóstico por imagen , Calcinosis/patología , Calcinosis/cirugía , Carcinoma Papilar/patología , Carcinoma Papilar/cirugía , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estadística como Asunto , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/patología , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Tiroiditis/diagnóstico por imagen , Tiroiditis/patología , Tiroiditis/cirugía , Ultrasonografía Intervencional , Adulto JovenRESUMEN
ABSTRACT: estrogen receptor (ER)+/human epithelial growth factor receptor 2 (HER2)- breast cancers have less aggressive traits and a favorable prognosis when treated early. Prediction of prognosis for treatment outcome or survival in ER+/HER2- cancer is important. Ultrasound (US) is an effective and easy technique for breast cancer diagnosis and tumor characterization. Positron emission tomography/computed tomography (PET/CT) is widely used for diagnosis, staging, and therapeutic response in cancer evaluation, and a high maximum standardized uptake value (SUVmax) is associated with poor prognosis. The study aim was to compare the prognostic value of US features with that of the SUVmax assessed by PET/CT in ER+/HER- breast cancer patients. We retrospectively identified breast cancer patients in our institutional database who had undergone preoperative US and PET/CT, and 96 patients with invasive ductal carcinoma and ductal carcinoma in situ were included in this study. The US features of mass shape, margin, echo pattern, orientation, posterior features, boundary, and calcification in the mass were analyzed. We then analyzed the US features to look for correlations with SUVmax and associations with margins, boundaries, posterior features, histological grade, and ki-67 expression. High SUVmax was correlated with irregular shape, not-circumscribed margin, posterior acoustic enhancement, echogenic halo, and calcification in the mass (P < 0.05, all). Posterior acoustic enhancement was correlated with high ki-67 expression. Many US features of ER+/HER- breast cancer showed associations with SUVmax. Some US features of ER+/HER- breast cancer were useful for predicting prognosis.
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Neoplasias de la Mama , Fluorodesoxiglucosa F18 , Neoplasias de la Mama/diagnóstico por imagen , Receptor beta de Estrógeno , Femenino , Fluorodesoxiglucosa F18/metabolismo , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Pronóstico , Receptores de Estrógenos/metabolismo , Receptores de Factores de Crecimiento , Estudios RetrospectivosRESUMEN
OBJECTIVES: To describe how health care crisis resulting from the COVID-19 pandemic in South Korea has led to innovation and changes to government policy. This paper presents the significant cluster events, relevant developments of innovation, and economical impact in Korea that could inform policy makers on how to respond to health crises in the future. METHODS: Health care, economy, epidemiological data are collected from various sources including the Korea Centers for Disease Control and Prevention (KCDC) or other government sources. RESULTS: The KCDC jointly with medical professionals developed a series of innovations such as 1) Full contact tracing and rapid testing with a 12 h turnaround and 10 min movement tracking systems, 2) transparent disclosure of all contract tracing data to the public through a central database, 3) Drive-Through and Walk-Through testing methods, and 4) a 4 tier patient severity index and community treatment isolation centers. Korea moved from the 4th in the world for total confirmed cases in March down to 76th in August. CONCLUSIONS: Expedited enforcement of amended legislation acts to protect the healthcare workforce resulted in only 10 healthcare professionals contracting the virus while caring for Covid-19 patients. This has resulted in minimal human capital loss and the government was able to re-direct existing medical workforce to areas in need. The quarantine strategies implemented resulted in little need to lock down the whole economy but also limited the cost spent to gain a year of life to 193,848 Won (US$163).
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PURPOSE: To evaluate magnetic resonance (MR) imaging for the discrimination between low-grade chondrosarcoma and enchondroma. MATERIALS AND METHODS: MR images of 34 patients who were confirmed with low-grade chondrosarcoma or enchondroma were retrospectively reviewed. After review of medical records, MR findings in 18 patients with low-grade chondrosarcoma and 16 patients with enchondroma were compared. MR images were retrospectively reviewed for the lesion location (central or eccentric; epiphysis, metaphysic, or diaphysis), margin, contour, mineralized matrix, endosteal scalloping, cortical expansion, cortical destruction, soft tissue mass formation, and periosteal reaction. Signal intensity, the patterns of contrast enhancement (unilocular or multilobular), soft tissue mass, and adjacent abnormal bone marrow and soft tissue signal were also reviewed. Statistical analysis was performed with chi-square test. RESULTS: The patients with low-grade chondrosarcoma had a significantly higher incidence of MR findings (P<.05): predominantly intermediate signal on T1-weighted images [72% (13/18) in low-grade chondrosarcoma vs. 25% (4/16) in enchondroma], multilocular appearance on contrast-enhanced T1-weighted images [83% (15/18) vs. 44% (7/16)], cortical destruction [33% (6/18) vs. 0% (0/16)], a soft tissue mass [28% (5/18) vs. 0% (0/16)], adjacent bone marrow and soft tissue abnormal signal [22% (4/18) vs. 0% (0/16)], and an involvement of the epiphysis or flat bone [56% (10/18) vs. 19% (3/16)]. CONCLUSION: MR imaging shows helpful features for differentiating low-grade chondrosarcoma from enchondroma.
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Neoplasias Óseas/patología , Condroma/patología , Condrosarcoma/patología , Imagen por Resonancia Magnética/métodos , Neoplasias de los Tejidos Blandos/patología , Adolescente , Adulto , Anciano , Niño , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
CONTEXT: Few reports have determined whether preoperative detection of the BRAF V600E mutation in fine-needle aspiration biopsy (FNAB) may influence determination of surgical extent such as prophylactic central lymph node dissection (CLND) in patients with papillary thyroid carcinoma (PTC). OBJECTIVES: Our objectives were to investigate whether preoperative BRAF analysis may assist determination of surgical extent, including prophylactic CLND with variable clinicopathological risk factors for central lymph node metastasis, in patients with PTC and clinically node-negative neck. PATIENTS AND METHODS: From July 2009 to May 2011, we prospectively enrolled 148 PTC patients with clinically node-negative neck who received a total thyroidectomy and prophylactic CLND. BRAF mutation by pyrosequencing was tested on preoperative FNAB specimens. The relationships between occult central lymph node metastasis and preoperative BRAF mutation or clinicopathological factors were analyzed. Additionally, we assessed the associations between preoperative BRAF mutation status and various clinicopathological characteristics of PTC revealed postoperatively. RESULTS: The prevalence of the BRAF V600E mutation was 53.4%, and the rate of occult central lymph node metastasis was 25.7%. Multivariate analysis showed that tumor size over 1 cm [P = 0.006; odds ratio (OR) = 3.559], perithyroidal invasion (P = 0.023; OR = 2.893), and preoperative positive BRAF mutation (P = 0.029; OR = 2.727) were independent risk factors for the presence of occult central lymph node metastasis. BRAF mutation examined in FNAB specimens, compared with the wild-type allele, strongly predicted perithyroidal invasion (48 vs. 29%; P = 0.017), extracapsular spread (65 vs. 45%; P = 0.017), occult central lymph node metastasis (35 vs. 15%; P = 0.004), and advanced TNM stage (44 vs. 28%; P = 0.035). In the multivariate analysis, patients with preoperative positive BRAF mutation were significantly more likely (P = 0.023; OR = 2.848) to have occult central lymph node metastasis. CONCLUSION: Preoperative BRAF analysis by FNAB and primary tumor size based on ultrasonography may assist in predicting occult central lymph node metastasis in patients with PTC and clinically node-negative neck.