Min Jae Cha

Clinical impact of minimal micropapillary pattern in invasive lung adenocarcinoma: prognostic significance and survival outcomes.

Micropapillary subtype has recently been established to be a distinct marker for poor prognosis in lung adenocarcinomas. According to the current classification of lung adenocarcinomas, all subtypes are listed semiquantitatively in 5% increments. In other words, a minimal amount of the micropapillary pattern, precisely <5% of the entire tumor is disregarded. Therefore, we sought to assess the prognostic significance and survival outcomes in patients with a micropapillary pattern proportion of <5% of the entire tumor. A total of 525 patients with lung adenocarcinoma were classified into 3 subgroups according to the presence and proportion of micropapillary subtype: (1) ≥5% of the micropapillary pattern (n=114); (2) <5% of the micropapillary pattern (n=115); and (3) absence (<1%) of the micropapillary pattern (n=296). Sex, TNM stage, lymph node status (N status), tumor size, and predominant subtype demonstrated a significant difference among the 3 subgroups. Overall survival (OS) and disease-free survival (DFS) were significantly different among the 3 subgroups (P=0.009 and 0.001 for OS and DFS, respectively). Furthermore, OS was significantly better in patients without the micropapillary pattern (<1%) than in those with <5% (P=0.034). At multivariate analyses, age (P=0.005) and N status (P=0.005) were independent prognostic factors influencing OS. In conclusion, our results demonstrated that even a small proportion of the micropapillary pattern, specifically <5% of the entire tumor has a significant prognostic impact on OS. N status remained an independent prognostic factor that negatively influenced OS.

Prognosis in Resected Invasive Mucinous Adenocarcinomas of the Lung: Related Factors and Comparison with Resected Nonmucinous Adenocarcinomas

Introduction: In the 2015 World Health Organization classification, invasive mucinous adenocarcinoma (IMA) is categorized as one of various subtypes of lung invasive adenocarcinoma (ADC). However, no comprehensive analysis regarding the clinicoradiologic and prognostic features of IMA has been reported. We aimed to report prognostic factors in IMA and to compare the prognosis of IMAs with that of nonmucinous ADCs. Methods: We included 81 patients with a solitary IMA of the lung and analyzed them from the standpoint of clinicoradiologic presentation. Survival rates were assessed and compared with those of 646 resected solitary invasive nonmucinous ADCs. Results: Patients with IMA showed longer disease‐free survival (DFS) than did those with nonmucinous ADCs, whereas overall survival (OS) did not differ significantly (p = 0.023 and p = 0.824, respectively). The DFS of patients with IMA was between that of patients with lepidic predominant (low‐grade) and acinar/papillary predominant (intermediate‐grade) ADC. In terms of OS, the survival curve of IMA was similar to that of acinar/papillary predominant ADC. Multivariate analysis revealed that tumor size (hazard ratio [HR] = 1.370, 95% confidence interval [CI]: 1.141–1.645, p = 0.001) and maximum standardized uptake value (HR = 1.338, 95% CI: 1.160–1.544, p < 0.001) were independent poor prognostic predictors for DFS. Regarding OS, tumor size (HR = 1.309, 95% CI: 1.092–1.570; p = 0.004) was the only predictor of poor prognosis. Conclusion: Patients with IMA demonstrate a DFS between that of patients with low‐grade nonmucinous ADC and that of patients with intermediate‐grade nonmucinous ADC and an OS similar to that of patients with intermediate‐grade nonmucinous ADC. In IMA, tumor size and maximum standardized uptake value are the factors related to mitigating DFS and tumor size is the only predictor for reduced OS.

Diagnosis of neonatal ovarian torsion: Emphasis on prenatal and postnatal sonographic findings.

Our aim was to retrospectively review the imaging findings of patients with neonatal ovarian torsion, emphasizing prenatal and postnatal sonographic findings.

Improvement in imaging diagnosis technique and modalities for solitary pulmonary nodules: from ground-glass opacity nodules to part-solid and solid nodules

SUMMARY With advances in CT technology and the popularity of low-dose CT as a device for lung cancer screening, the detection rate of sub-solid pulmonary nodules as well as solid nodules has been increased. Distinguishing solid from sub-solid features is an essential step in the CT evaluation of solitary pulmonary nodules (SPNs) because strategies for nodule characterization and guidelines for management are different for each category. In addition to conventional CT parameters, numerous novel concepts and modalities have been developed. Although there is currently no single effective method for differentiating malignant from benign nodules, growth rate measurement using volumetry, evaluation of tumor vascularity on dynamic helical CT, dual-energy CT and MRI and physiologic evaluation with PET/CT can all be useful for nodule characterization. New techniques such as tomosynthesis can improve detection over radiography alone. The purpose of this article is to enhance our understanding of the evidence-based strategies involved in diagnosing SPNs.

Triple rule-out CT angiography protocol with restricting field of view for detection of pulmonary thromboembolism and aortic dissection in emergency department patients: simulation of modified CT protocol for reducing radiation dose.

Background Triple rule-out computed tomography (TRO CT) is a CT protocol designed to simultaneously evaluate the coronary, aorta, and pulmonary arteries. Purpose To evaluate potential diagnostic performance of TRO CT with restricted volume coverage for detection of pulmonary thromboembolism (PTE) and aortic dissection (AD). Material and Methods This study included 1224 consecutive patients with acute chest pain who visited the emergency department and underwent TRO CT using a 128-slice dual-source CT. Image data were reconstructed according to the display field of view (DFOV) of coronary CT angiography (CCTA) and TRO CT protocols in each patient. The presence of PTE and AD was evaluated by independent observers in each DFOV. The radiation dose was calculated to evaluate the potential benefits by restricting z-axis coverage to cardiac scan range instead of the whole thorax. Results Among all patients, 22 cases with PTE (1.9%) and nine cases with AD (0.8%) were found. Except for one PTE case, all cases were detected on both DFOV of TRO CT and CCTA. Mean effective dose for evaluation of entire thorax and cardiac scan coverage were 5.9 ± 1.1 mSv and 3.5 ± 0.7 mSv, respectively. Conclusion Isolated PTE and AD outside the CCTA DFOV rarely occur. Therefore, modified TRO CT protocol using cardiac scan coverage can be adopted to detect PTE and AD with reduced radiation dose.

Pulmonary Intravascular Lymphomatosis: Clinical, CT, and PET Findings, Correlation of CT and Pathologic Results, and Survival Outcome

Purpose To describe clinical, computed tomographic (CT), and positron emission tomographic (PET) features, correlation of CT and pathologic results, and survival of patients with pulmonary intravascular lymphomatosis. Materials and Methods The institutional review board approved this retrospective study with waiver of patient consent. Forty-two patients with pulmonary intravascular lymphomatosis were identified, 11 (26%) of whom showed lung involvement. CT features were correlated with histopathologic results. Clinical and survival outcomes were compared between patients with and those without pulmonary involvement by adopting the χ(2), Student t, or Kaplan-Meier analysis with log-rank tests. Results At clinical presentation, all 11 patients showed B symptoms (systemic symptoms of fever, night sweats, and weight loss), 10 had respiratory and four had neurologic symptoms, and two had skin lesions. Patients received cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy with (n = 5) or without (n = 6) rituximab, and seven (64%) patients died. Patients with lung involvement showed reduced overall and recurrence-free survival (median; 10.8 and 18.9 months, respectively) compared with those without lung involvement (median, 18.4 and 31.0 months, respectively) (P = .338 and .065, respectively). The most common CT abnormality was bilateral ground-glass opacity (GGO, n = 10), with increased fluorodeoxyglucose uptake at PET/CT (seven of seven patients). GGO correlated histopathologically with the expanded alveolar septal vasculatures and perivascular spaces filled with neoplastic lymphoid cells. Conclusion Pulmonary intravascular lymphomatosis appeared as bilateral GGO on CT images, with increased fluorodeoxyglucose uptake on PET/CT images. GGO on CT images correlated with the area of expanded alveolar septae because of distended vessels filled with neoplastic lymphoid cells. (©) RSNA, 2016 Online supplemental material is available for this article.

Iterative reconstruction: comparison of techniques for reduced-dose liver computed tomography following transarterial chemoembolization for hepatocellular carcinoma

Background Adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) algorithms have the potential to reduce dose while maintaining image quality. Purpose To compare computed tomography (CT) image quality and diagnostic performance among three reconstruction techniques – ASIR, MBIR, and filtered back projection (FBP) – after transcatheter arterial chemoembolization (TACE) of hepatocellular carcinomas (HCC). Material and Methods Of 60 patients that underwent initial TACE for HCCs, half underwent dynamic liver CT with conventional scanning protocol, and the other half with dose reduction to approximately 60% of conventional exposure. All images were reconstructed using three algorithms: FBP, ASIR, and MBIR. For objective analysis, image noise and signal-to-noise ratio (SNR) were compared. For subjective analysis, three radiologists independently assessed image quality. Ability to detect viable HCCs was also evaluated. Results MBIR and ASIR produced images with less noise and higher SNR compared with FBP regardless of radiation dosage (P < 0.017). However, in terms of subjective parameters, such as image blotchiness, artifacts, and overall quality, MBIR was inferior to FBP and ASIR (P < 0.001). Regarding diagnostic performance, there were no significant differences among reviewers in the detection of viable HCCs depending on the reconstruction algorithm, regardless of the dose reduction protocol (P > 0.017). Conclusion Although subjective evaluations suggest that MBIR images are of lower quality compared with FBP and ASIR regardless of radiation dosage, there were no significant differences among reconstruction algorithms in diagnosis of viable HCC after TACE.

Unrecognized myocardial infarction detected on cardiac magnetic resonance imaging: Association with coronary artery calcium score and cardiovascular risk prediction scores in asymptomatic Asian cohort

Background To investigate the association between unrecognized myocardial infarction (UMI) assessed with cardiac magnetic resonance (CMR) and coronary artery calcium (CAC) and cardiovascular risk prediction scores in asymptomatic Asian subjects. Materials and methods Total 872 asymptomatic subjects without prior cardiovascular event (male:female, 817:55; age, 53.88 ± 5.91) who underwent both CMR and CAC scoring CT were included. UMI were accessed and framingham risk score (FRS) and ASCVD (atherosclerotic cardiovascular disease) risk score by ACC/AHA were calculated. Results Late gadolinium enhancement indicating UMI was noted in 23 of 872 subjects (2.64%), but only three of them showed ECG abnormality (13.04%). Subjects with UMI showed higher CAC scores, FRS, and ASCVD scores than those without UMI (p < .001, p = .011 and p = .024, respectively). The prevalence of UMI differed significantly according to the CAC scores as follows: 1% in CAC = 0 (4/403), 1% in 1 ≤ CAC <100 (2/293), 6.1% in 100 ≤ CAC < 400 (7/114) and 14.5% in CAC ≥ 400 (9/62), respectively (p < .001). Receiver operating characteristics (ROC) analysis by using CAC score demonstrated an area under the curve (AUC) of 0.816 (95% confidence interval (CI), 0.780–0.848; p < .0001) for predicting UMI, which is superior to FRS [AUC, 0.712; 95% CI, 0.671–0.751; p = .009] and ASCVD risk score [AUC, 0.689; 95% CI, 0.648–0.729; p = .036]. Conclusion The prevalence of UMI increases with increasing burden of CAC and FRS. CAC score is a good discriminator for UMI, superior to FRS and ASCVD score, in asymptomatic population.

Relationship between cardiovascular risk factors and myocardial strain values of both ventricles in asymptomatic Asian subjects: measurement using cardiovascular magnetic resonance tissue tracking

The purpose of this study was to evaluate the association between myocardial deformation parameters and cardiovascular risk factors in asymptomatic Asian subjects and to provide reproducibility for deformation parameters of both ventricles using cardiovascular magnetic resonance (CMR) tissue tracking (TT). We enrolled 129 asymptomatic healthy adults who underwent CMR and assessed the cardiovascular risk factors in all individuals. All subjects had normal left ventricular systolic function. Commercial software was used to derive myocardial deformation parameters of both ventricles from short-axis cine images and long-axis cine images with two-, three-, and four-chamber views. Linear regression analysis was performed for evaluation of the association with all strain parameters for each age and systolic blood pressure. Intra class correlation was also calculated in CMR-TT to determine interobserver variability. In all 129 patients, the strain values for the left ventricle (LV) were 48.90 ± 9.05 for radial strain (RS, %), − 22.30 ± 2.33 for circumferential strain (CS, %), and − 19.76 ± 2.22 for longitudinal strain (LS, %). The strain values for the right ventricle (RV) were 18.63 ± 6.52 for RS, − 10.60 ± 3.33 for CS, and − 25.06 ± 3.01 for LS. In all 129 patients (male, n = 105), all strain parameters of LV and RV was significantly different among males and females (all p values < 0.05). The LV strain parameters were significantly associated with age by univariate linear regression analysis: RS, beta = 0.219, p = 0.002; CS, beta = − 0.668, p = 0.014 (except for LS, beta = − 0.104, p = 0.720). With regard to hypertension, diabetes mellitus and dyslipidemia, the values of all strain parameters in both ventricles were not significantly different between individuals with or without risk factors. Inter-observer agreement for three strain variables of LV and RV was 0.915 and 0.715 by iota index, and intra-observer agreement of LV and RV was 0.955 and 0.959 by iota index. The strain parameters by CMR-TT showed an association with age and significant difference in gender, on the other hands, not significantly different between with or without of the other conventional cardiovascular risk factors. The reproducibility of three LV strain parameters was higher than that of the respective RV strain parameters.

Clinical implication of radiographic scores in acute Middle East respiratory syndrome coronavirus pneumonia: Report from a single tertiary-referral center of South Korea

Abstract The aim of this study is to determine the earliest cutoff of radiographic score as a potential prognostic indicator of fatal outcomes in patients with acute Middle East respiratory syndrome coronavirus (MERS-CoV) pneumonia. The institutional review board approved this retrospective study. Serial chest radiographies (CXRs) were obtained from viral exposure until death or discharge in 35 patients with laboratory confirmed MERS-CoV infection. Radiographic scores were calculated by multiplying a four-point scale of involved lung area and three-point scale of abnormal opacification, in each of the six lung zones. Receiver operating characteristics (ROC) analyses were performed to identify optimal day and radiographic score for the prediction of respiratory distress, and univariate and multivariate logistic regression analyses were performed to assess significant predictive factors for intubation or tracheostomy. Among 35 patients (22 men, 13 women; median age: 48 years), 25 demonstrated abnormal opacity on CXR (MERS pneumonia), whereas no abnormality was detected in 10 patients (MERS upper respiratory tract infection). Seven patients required ventilator support (intubation group) and three of them eventually expired. The average incubation period was 5.4 days (standard deviation, ±2.8; range, 2–11). Patients in the intubation group had a higher incidence of diffuse lung involvement, higher radiographic scores, and fibrosing sequela on follow up study compared with those in the non-intubation group. However, patients’ age and comorbidity did not differ significantly between the two groups. The ROC analysis revealed an area under curve of 0.726 for the radiographic score on day 10 with an optimal cutoff score of 10 for prediction of intubation, with a sensitivity of 71% and specificity of 67%. Our study suggest that MERS patients with radiographic score > 10 on day 10 from viral exposure require aggressive therapy with careful surveillance and follow-up evaluation.