This paper considers monitoring an anomaly from sequentially observed time series with heteroscedastic conditional volatilities based on the cumulative sum (CUSUM) method combined with support vector regression (SVR). The proposed online monitoring process is designed to detect a significant change in volatility of financial time series. The tuning parameters are optimally chosen using particle swarm optimization (PSO). We conduct Monte Carlo simulation experiments to illustrate the validity of the proposed method. A real data analysis with the S&P 500 index, Korea Composite Stock Price Index (KOSPI), and the stock price of Microsoft Corporation is presented to demonstrate the versatility of our model.

Mediastinal tuberculous lymphadenitis rarely mimics esophageal submucosal tumor, particularly in the case of multidrug-resistant tuberculosis (MDR-TB). Herein, we report the case of a 61-year-old woman who visited a local hospital complaining of odynophagia. An initial esophagogastroduodenoscopy revealed an esophageal submucosal tumor, and subsequent chest computed tomography showed subcarinal lymphadenopathy with an esophagomediastinal fistula. The patient was then referred to Samsung Medical Center, and a second esophagogastroduodenoscopy showed deep central ulceration, as well as a suspicious fistula in the esophageal submucosal tumor-like lesion. A biopsy examination of the ulcerative lesion confirmed focal inflammation only. Next, an endobronchial, ultrasound-guided lymph node biopsy was performed, and TB was confirmed. The patient initially began a course of isoniazid, rifampicin, ethambutol, and pyrazinamide. However, after a drug sensitivity test, she was diagnosed with MDR-TB, and second-line anti-TB medications were prescribed. She recovered well subsequently.

Background: The differential diagnosis of immunoglobulin G4-sclerosing cholangitis (IgG4-SC) from primary sclerosing cholangitis (PSC) or cholangiocarcinoma (CCA) is important. In this study, we aimed to find the best combinations of serum IgG subclasses and IgG4 levels for differentiating IgG4-SC from PSC or CCA. Methods: In total, 31 patients with IgG4-SC, 27 patients with PSC, and 40 patients with CCA were enrolled from 2003 to 2017 at a single tertiary referral center. We retrospectively assessed the IgG4, IgG4/IgG1, IgG4/(IgG1+IgG3), and (IgG4+IgG2)/(IgG1+IgG3) in each of the patients. ROC curves were established to obtain the optimal cutoff value for each parameter. McNemar’s test was used to compare the sensitivities, specificities, and accuracies of diagnostic algorithms. Results: In differentiating IgG4-SC from PSC, the accuracies of IgG4/IgG1 ≥ 0.087 and of IgG4/(IgG1+IgG3) ≥ 0.081 were significantly higher than that of IgG4 ≥ 135 mg/dL alone (78% vs. 66%, p = 0.025). Serum IgG4 ≥ 52 mg/dL showed the best accuracy for differentiation of IgG4-SC from CCA, with a sensitivity and specificity of 80% and 82%, respectively, but this was statistically not significant (p = 0.405). Conclusions: The serum IgG4/IgG1 or IgG4/(IgG1+IgG3) level may help to differentiate IgG4-SC from PSC. IgG4 alone is the most accurate serologic marker for the differentiation of IgG4-SC from CCA.

Background:Clonorchis sinensis (CS) infection is considered a group 1 carcinogen of cholangiocarcinoma (CCA). There were very few studies regarding clinical characteristics of CS-associated CCA (CACC). This study aimed to investigate clinical characteristics of patients with CCA with or without CS infection.Methods: A total of 367 patients diagnosed with CCA who underwent diagnostic tests for CS infection were enrolled. CS infection was defined as follows: at least one positive serum ELISA test, skin test, stool microscopy, or bile microscopy.Results: There were 95 (26%) patients with CS infections. The median follow-up duration was 14.9 months (range, 6.07–36.17). The following significant differences were noted among patients with CACC compared to non-CACC; diagnosis at younger age (median 62 years vs. 65 years, p = 0.018), higher male to female ratio (83.2 vs. 61.8%, p < 0.001), and residence in CS-endemic area (46.3 vs. 25.4%, p = 0.014). Univariate analysis of prognostic factors indicated that tumor location, curative resection, tumor stage, and laboratory tests including CA 19-9, CEA, and bilirubin were significantly associated with overall survival, but CS infection was not. In multivariate analysis, tumor location, CEA, curative resection and tumor stage were identified as independent prognostic factors. Among patients under age 64, CACC group had lower survival rate than non-CACC group (p = 0.022).Conclusions: CACC had the following significant characteristics compared to non-CACC; diagnosis at younger age, higher male to female ratio, higher prevalence in CS endemic areas and poorer overall survival in patients under age 64.

Since superior vena cava syndrome (SVCS) is a critical condition, immediate diagnostic approach and therapy are imperative to avoid potentially life-threatening complications. Here, we report a case of lung cancer with SVCS, which was diagnosed through intravascular tumor biopsy using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). EBUS-TBNA enabled us to obtain tissue sufficient for diagnosis, without significant complications. Prompt diagnosis was followed by appropriate anticancer treatment and improvement in the symptoms. For patients suspected of SVCS and requiring prompt pathologic diagnosis, we can consider EBUS-TBNA to diagnose intravascular or mediastinal tumors and provide an accurate diagnosis.

Here we describe a case of rapidly expanding ascending aortic aneurysm in a patient with relapsing polychondritis. To prevent aneurysm rupture, the patient underwent emergent surgical repair. Silent inflammation can progress in the aorta wall, even in asymptomatic patients with mild disease activity under immunosuppressive treatment, leading to the rapid growth of aortic aneurysms. Close monitoring with routine imaging is needed once a patient with relapsing polychondritis is diagnosed with an aortic aneurysm.