Geewon Lee

Clinical Implication of PET/MR Imaging in Preoperative Esophageal Cancer Staging: Comparison with PET/CT, Endoscopic Ultrasonography, and CT

This was a study to compare the diagnostic efficacies of endoscopic ultrasonography (EUS), CT, PET/MR imaging, and PET/CT for the preoperative local and regional staging of esophageal cancer, with postoperative pathologic stage used as the reference standard. Methods: During 1 y, 19 patients with resectable esophageal cancer were enrolled and underwent preoperative EUS, CT, PET/CT, and PET/MR imaging. A chest radiologist and nuclear medicine physician retrospectively reviewed the images and assigned tumor and lymph node stages according to the seventh version of the TNM system and the American Joint Committee on Cancer staging system. Four patients who were treated nonsurgically were excluded from data analysis. The efficacies of EUS, CT, PET/CT, and PET/MR imaging were compared. Results: Primary tumors were correctly staged in 13 (86.7%), 10 (66.7%), and 5 (33.3%) patients at EUS, PET/MR imaging, and CT, respectively (P value ranging from 0.021 to 0.375). The accuracy of determining T1 lesions was 86.7%, 80.0%, and 46.7% for EUS, PET/MR imaging, and CT, respectively. For distinguishing T3 lesions, the accuracy was 93.3% for EUS and 86.7% for both PET/MR imaging and CT. For lymph node staging, the accuracy was 83.3%, 75.0%, 66.7%, and 50.0% for PET/MR imaging, EUS, PET/CT, and CT, respectively. In addition, area-under-the-curve values were 0.800, 0.700, 0.629, and 0.543 for PET/MR imaging, EUS, PET/CT, and CT, respectively. Conclusion: PET/MR imaging demonstrated acceptable accuracy for T staging compared with EUS and, although not statistically significant, even higher accuracy than EUS and PET/CT for prediction of N staging. With adjustments in protocols, PET/MR imaging may provide an important role in preoperative esophageal cancer staging in the future.

Nodular Bronchiectatic Mycobacterium avium Complex Pulmonary Disease. Natural Course on Serial Computed Tomographic Scans

RATIONALE Existing literature is inconclusive regarding how the nodular bronchiectatic form of Mycobacterium avium complex (MAC) disease will progress without treatment and when treatment initiation should be considered. OBJECTIVES To assess the natural course of MAC pulmonary disease by serial thin-section computed tomography (CT). METHODS Of 339 patients with nodular bronchiectatic form of MAC disease, we selected 265 untreated patients who had serial CTs (mean observation period, 32 ± 21 mo). Two independent chest radiologists reviewed retrospectively all CT scans for the presence and extent of lung abnormalities (maximal total score, 30). MEASUREMENTS AND MAIN RESULTS Of 265 patients, 126 patients (48%) had disease that had progressed and that needed treatment owing to radiologic deterioration or worsening symptoms, and the remaining 139 patients (52%) did not. On multivariate analysis, the presence of cavity (adjusted hazard ratio, 2.06; P = 0.004) and consolidation (adjusted hazard ratio, 1.55; P = 0.019) at initial CT remained as independent factors associated with disease progression and treatment requirement. The presence of cavitary lesions demonstrated the highest positive predictive value (61%) and significant correlation (P = 0.005) with smear positivity. Differences in the extent of each pattern and total CT score in the serial studies were significantly larger (P < 0.05) in patients requiring treatment. The total CT score increased by 2.41 in the treatment-requiring group compared with 0.25 in the group that did not receive treatment. CONCLUSIONS Without treatment, about half of patients demonstrate progressive disease on serial CT over a mean follow-up period of 32 months and, thus, required treatment. Patients showing cavities or consolidation on initial CT are more likely to have progressive disease and thus to require treatment eventually.

The development of rapid real-time PCR detection system for Vibrio parahaemolyticus in raw oyster

Aims:  To develop a new rapid real‐time polymerase chain reaction (PCR) based detection system for Vibrio parahaemolyticus (V. parahaemolyticus) applicable to raw oyster samples.

Serial CT Findings of Nodular Bronchiectatic Mycobacterium avium Complex Pulmonary Disease With Antibiotic Treatment

OBJECTIVE The objective of our study was to analyze the serial CT findings of patients with the nodular bronchiectatic form of Mycobacterium avium complex (MAC) pulmonary disease treated with antibiotic therapy. MATERIALS AND METHODS Between January 2005 and December 2009, MAC lung disease was diagnosed in 475 patients at a single tertiary referral hospital. Of the 475 patients, 339 had a CT pattern of disease consistent with the nodular bronchiectatic form. Among these 339 patients, 110 patients treated with a combination of antibiotics for 1 year were selected for this study. Two independent chest radiologists reviewed retrospectively the chest CT scans of 101 patients (M. avium disease [n = 57] and M. intracellulare disease [n = 44]) in whom serial CT scans had been obtained at the beginning of and at 12 months after standardized therapy. Each CT study was assessed for the presence and extent of lung parenchymal abnormalities (maximum score, 30). RESULTS After 12 months of antibiotic therapy, 84 patients (83%) had a decrease in the overall CT score, three (3%) had an increase, and 14 (14%) had no change in disease extent. The decrease in total CT score was statistically significant (overall score difference, 2.54; p < 0.0001). Cellular bronchiolitis showed the largest decrease in extent (difference in mean pre and posttreatment scores, -1.02, -1.07, and -0.94 for MAC, M. avium, and M. intracellulare diseases, respectively). Before treatment, patients with M. intracellulare disease showed more extensive disease than patients with M. avium disease (total CT score, 13.31 vs 11.10; p = 0.025). CONCLUSION In the nodular bronchiectatic form of MAC pulmonary disease, lung parenchymal abnormalities show a significant decrease in extent on CT after antibiotic treatment and the decrease is mainly related to the improvement of cellular bronchiolitis.

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.

Thymic Epithelial Tumors: Prognostic Determinants Among Clinical, Histopathologic, and Computed Tomography Findings

BACKGROUND The Masaoka-Koga staging system has been known as the strongest prognostic factor for both survival and recurrence of thymic epithelial tumor (TET). The purpose of our study was to find prognostic determinants among computed tomography (CT), histopathologic, and clinical features of TET. METHODS Two radiologists reviewed retrospectively CT findings of 437 patients (male 242, female 195; mean age, 51 years) with TET. With medical record review, surgico-histopathologic results were subcategorized into Masaoka-Koga stages I through IV and World Health Organization histopathologic classifications A-B1, B2-B3, and carcinoma. Overall survival and progression-free survival were analyzed. Clinical, histopathologic, and CT features were correlated from each other. RESULTS In all, 437 tumors were in Masaoka-Koga stage I (n = 147, 33.6%), stage II (n = 121, 27.7%), stage III (n = 76, 17.4%), or stage IV (n = 93, 21.3%); A and B1 (n = 114, 26.1%) and B2 and B3 TET (n = 223, 51.0%); and thymic carcinoma (n = 100, 22.9%). In multivariable analyses, age, Masaoka-Koga stage IV, thymic carcinoma, and CT stages III and IV were significantly correlated with overall survival (p < 0.05), whereas adjuvant treatment, Masaoka-Koga stages III and IV, World Health Organization B2 and B3, thymic carcinoma, R2 resection, CT size, and CT stage IV were significantly associated with progression-free survival (p < 0.05). Computed tomography stages showed moderate association with Masaoka-Koga stages (K = 0.621). CONCLUSIONS For TET, CT staging is effective in distinguishing both overall survival and progression-free survival, and patients with Masaoka-Koga stage IV or thymic carcinoma or CT stage IV have the worst prognosis.

Effectiveness of Adaptive Statistical Iterative Reconstruction for 64-Slice Dual-Energy Computed Tomography Pulmonary Angiography in Patients With a Reduced Iodine Load: Comparison With Standard Computed Tomography Pulmonary Angiography.

Objective The aim of the study was to assess the effectiveness of the adaptive statistical iterative reconstruction (ASIR) for dual-energy computed tomography pulmonary angiography (DE-CTPA) with a reduced iodine load. Materials and Methods One hundred forty patients referred for chest CT were randomly divided into a DE-CTPA group with a reduced iodine load or a standard CTPA group. Quantitative and qualitative image qualities of virtual monochromatic spectral (VMS) images with filtered back projection (VMS-FBP) and those with 50% ASIR (VMS-ASIR) in the DE-CTPA group were compared. Image qualities of VMS-ASIR images in the DE-CTPA group and ASIR images in the standard CTPA group were also compared. Results All quantitative and qualitative indices, except attenuation value of pulmonary artery in the VMS-ASIR subgroup, were superior to those in the VMS-FBP subgroup (all P < 0.001). Noise and signal-to-noise ratio of VMS-ASIR images were superior to those of ASIR images in the standard CTPA group (P < 0.001 and P = 0.007, respectively). Regarding qualitative indices, noise was significantly lower in VMS-ASIR images of the DE-CTPA group than in ASIR images of the standard CTPA group (P = 0.001). Conclusions The ASIR technique tends to improve the image quality of VMS imaging. Dual-energy computed tomography pulmonary angiography with ASIR can reduce contrast medium volume and produce images of comparable quality with those of standard CTPA.

Imaging Phenotyping Using Radiomics to Predict Micropapillary Pattern within Lung Adenocarcinoma

Introduction Lung adenocarcinomas (ADCs) with a micropapillary pattern have been reported to have a poor prognosis. However, few studies have reported on the imaging‐based identification of a micropapillary component, and all of them have been subjective studies dealing with qualitative computed tomography variables. We aimed to explore imaging phenotyping using a radiomics approach for predicting a micropapillary pattern within lung ADC. Methods We enrolled 339 patients who underwent complete resection for lung ADC. Histologic subtypes and grades of the ADC were classified. The amount of micropapillary component was determined. Clinical features and conventional imaging variables such as tumor disappearance rate and maximum standardized uptake value on positron emission tomography were assessed. Quantitative computed tomography analysis was performed on the basis of histogram, size and shape, Gray level co‐occurrence matrix–based features, and intensity variance and size zone variance–based features. Results Higher tumor stage (OR = 3.270, 95% confidence interval [CI]: 1.483–7.212), intermediate grade (OR = 2.977, 95% CI: 1.066–8.316), lower value of the minimum of the whole pixel value (OR = 0.725, 95% CI: 0.527–0.98800), and lower value of the variance of the positive pixel value (OR = 0.961, 95% CI: 0.927–0.997) were identified as being predictive of a micropapillary component within lung ADC. On the other hand, maximum standardized uptake value and tumor disappearance rate were not significantly different in groups with a micropapillary pattern constituting at least 5% or less than 5% of the entire tumor. Conclusion A radiomics approach can be used to interrogate an entire tumor in a noninvasive manner. Combining imaging parameters with clinical features can provide added diagnostic value to identify the presence of a micropapillary component and thus, can influence proper treatment planning.

Isolated Left Ventricular Apical Hypoplasia with Infundibular Pulmonary and Aortic Stenosis: a Rare Combination

Isolated left ventricular (LV) apical hypoplasia is a rare congenital cardiac anomaly which is not accompanied by other cardiac abnormalities, with the exception of two cases. We report a case of a 33-year-old male patient with isolated LV apical hypoplasia combined with infundibular pulmonary stenosis and aortic stenosis. We review a literature focusing on the characteristic magnetic resonance features and combined cardiac abnormalities.

New-onset malignant pleural effusion after abscess formation of a subcarinal lymph node associated with endobronchial ultrasound-guided transbronchial needle aspiration.

We present a case of an unusual infectious complication of a ruptured mediastinal abscess after endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), which led to malignant pleural effusion in a patient with stage IIIA non-small-cell lung cancer. EBUS-TBNA was performed in a 48-year-old previously healthy male, and a mediastinal abscess developed at 4 days post-procedure. Video-assisted thoracoscopic surgery was performed for debridement and drainage, and the intraoperative findings revealed a large volume pleural effusion that was not detected on the initial radiographic evaluation. Malignant cells were unexpectedly detected in the aspirated pleural fluid, which was possibly due to increased pleural permeability and transport of malignant cells originating in a ruptured subcarinal lymph node from the mediastinum to the pleural space. Hence, the patient was confirmed to have squamous cell lung carcinoma with malignant pleural effusion and his TNM staging was changed from stage IIIA to IV.