Prediction of the risk of developing hepatocellular carcinoma in health screening examinees: a Korean cohort study.

BACKGROUND: Almost all Koreans are covered by mandatory national health insurance and are required to undergo health screening at least once every 2 years. We aimed to develop a machine learning model to predict the risk of developing hepatocellular carcinoma (HCC) based on the screening results and insurance claim data. METHODS: The National Health Insurance Service-National Health Screening database was used for this study (NHIS-2020-2-146). Our study cohort consisted of 417,346 health screening examinees between 2004 and 2007 without cancer history, which was split into training and test cohorts by the examination date, before or after 2005. Robust predictors were selected using Cox proportional hazard regression with 1000 different bootstrapped datasets. Random forest and extreme gradient boosting algorithms were used to develop a prediction model for the 9-year risk of HCC development after screening. After optimizing a prediction model via cross validation in the training cohort, the model was validated in the test cohort. RESULTS: Of the total examinees, 0.5% (1799/331,694) and 0.4% (390/85,652) in the training cohort and the test cohort were diagnosed with HCC, respectively. Of the selected predictors, older age, male sex, obesity, abnormal liver function tests, the family history of chronic liver disease, and underlying chronic liver disease, chronic hepatitis virus or human immunodeficiency virus infection, and diabetes mellitus were associated with increased risk, whereas higher income, elevated total cholesterol, and underlying dyslipidemia or schizophrenic/delusional disorders were associated with decreased risk of HCC development (p < 0.001). In the test, our model showed good discrimination and calibration. The C-index, AUC, and Brier skill score were 0.857, 0.873, and 0.078, respectively. CONCLUSIONS: Machine learning-based model could be used to predict the risk of HCC development based on the health screening examination results and claim data.

The Effect of Lung Volume on the Size and Volume of Pulmonary Subsolid Nodules on CT: Intraindividual Comparison between Total Lung Capacity and Tidal Volume.

Purpose: To examine the effect of lung volume on the size and volume of pulmonary subsolid nodules (SSNs) measured on CT. Materials and Methods: A total of 42 SSNs from 31 patients were included. CT examination was first performed at total lung capacity (TLC), and a section containing the nodule was additionally scanned at tidal volume (TV). The diameter and volume of each SSN, as well as the cross-sectional lung area containing the nodule, were measured. The significance of the changes in measurements between TLC and TV within the same individuals was evaluated. Results: The lung area and the diameter and volume of SSNs decreased significantly at TV by 12.7 cm2, 0.5 mm, and 46.4 mm3 on average, respectively (p < 0.001), compared to those at TLC. Changes in lung area between TV and TLC were positively correlated with the change in SSN diameter (p = 0.027) and volume (p = 0.014). However, after correction (by considering the change in lung area), the changes in SSN diameter (p = 0.124) and volume (p = 0.062) were not significantly different. Conclusion: SSN size and volume can be significantly affected by lung volume during CT scans of the same individuals.

Primary pulmonary meningioma: an unusual cause of a nodule with strong and homogeneous enhancement.

We report a case of a 61-year-old female with atypical chest pain. The chest CT scan revealed a well-circumscribed large intrapulmonary nodule that showed vigorous and homogeneous contrast enhancement. The nodule was diagnosed as a meningioma after surgery. Metastatic meningioma was excluded by brain and spine MRI scans. Primary pulmonary meningioma usually appears as a solitary well-defined round or lobulated nodule with variable enhancement on CT; this case is unique because of the intense and homogeneous enhancement. Although rare, primary pulmonary meningioma should be considered in the differential diagnosis of a well-defined pulmonary nodule with dense and homogeneous enhancement.

Inferior phrenic artery: anatomy, variations, pathologic conditions, and interventional management.

The inferior phrenic artery (IPA) is the most common source of extra-hepatic collateral blood supply for hepatocellular carcinoma (HCC) and frequently supplies HCCs located in the bare area of the liver. Other pathologic conditions including hemoptysis, diaphragmatic or hepatic bleeding due to trauma or surgery, and bleeding caused by gastroesophageal problems (eg, Mallory-Weiss tear or gastroesophageal cancer) may be related to the IPA. Over a 4-year period, the authors performed 383 interventional procedures related to the IPA. The right and left IPAs originate with almost equal frequency from the aorta and celiac axis and with lesser frequency from the renal arteries. Various other sites of origin-such as the left gastric, hepatic, superior mesenteric, spermatic, and adrenal arteries-are also seen. Radiologists must be familiar with the normal spectrum of IPA anatomy so that detection and adequate interventional management can be achieved when pathologic conditions related to the IPA are present.

Endobronchial metastasis of hepatocellular carcinoma.

Endobronchial metastasis (EBM) secondary to extrathoracic malignancies is rare among the various modes of pulmonary metastases. Of the many types of extrathoracic tumors capable of EBM, only one case of EBM from hepatocellular carcinoma has been reported, but radiologic findings were not described. We present the radiologic findings of surgically proven EBM in a patient with hepatocellular carcinoma. A chest radiograph revealed a tubular mass-like opacity in the right suprahilar region combined with mild volume decrease of the right upper lobe. Fiberoptic bronchoscopy had erroneously led to a diagnosis of endobronchial aspergilloma. The metastatic lesion was manifested as a branching pattern of enhanced endobronchial mass at the anterior segment of the right upper lobe on computed tomography.

Evaluation of the post-shunt status with electron beam computed tomography in cyanotic congenital heart disease.

The assessment of the accuracy of Electron Beam Computed Tomography (EBCT) for the follow-up of pulmonary vascular system after the shunt operation in cyanotic congenital heart diseases was purpose of the study. The study group consists of 16 consecutive patients with cyanotic congenital heart disease who had Blalock-Taussig (BT) shunt (n=7), bi- directional cavo-pulmonary shunt (BCPS, n=7) and unifocalization (n=2). EBT images were obtained on systolic phase under EKG gating and after intravenous administration of contrast agent. We evaluated the shunt patency, anatomy of intrapericardial pulmonary artery, parenchymal pulmonary vessels and background lung attenuation for the pulmonary blood flow, and the presence of systemic arterial and venous collaterals. Angiography (n=12) and echocardiography (n=16) were used as the gold standards. EBCT was consistent with angiogram in detecting the shunt patency and in depicting the anatomy of the intrapericardial pulmonary artery. Occlusion of the BT shunts was not detected in 2 patients by echocardiography. Diffuse or focally decreased pulmonary flow on EBCT in 8 patients was consistent with the pulmonary hemodynamics pattern revealed by cardiac catheterization. Uneven attenuation between lobes was related with multifocal supply of pulmonary flow or occlusion of lobar pulmonary arteries. Systemic collateral arteries were observed in 5 at the corresponding site of the decreased pulmonary flow. Systemic venous collaterals seen in all patients following BCPS were eventually draining to the inferior vena cava in 5 and to the left atrium in 2. EBCT provided accurate information of the pulmonary vascular system after shunt and has unique advantage over echocardiography in assessing patency of BT shunt or unifocalization tubes within the pleural space, the estimation of regional difference in pulmonary hemodynamics, and the detection of systemic collateral vessels. Therefore EBCT may provide useful information about the timing of definitive correction and the need for a second shunt or an interventional procedure prior to total repair.