Pulmonary embolism (PE), which can originate as a consequence of deep vein thrombosis (DVT), is the most frequent and potentially fatal venous thromboembolic event. Despite the fact that the incidence of venous thromboembolism (VTE) in Asians is lower than that in the Western populations, a recent epidemiologic study demonstrates an increasing incidence of VTE in the Korean population. Anticoagulants, including low molecular weight heparin (LMWH) and vitamin K antagonist (VKAs), have been the main treatments for PE, however, recently new oral anticoagulants (NOACs) were introduced. We will review how well patients with PE can be managed with the existing anticoagulants and NOACs along with the time span of treatment, which still pose some challenges for clinicians.

Background: Small cell lung cancer (SCLC) transformation during epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment in lung cancer has been suggested as one of possible resistance mechanisms. Methods: We evaluated whether SCLC transformation or neuroendocrine (NE) differentiation can be found in the cell line model. In addition, we also investigated its effect on responses to conventional chemotherapeutic drugs of the SCLC treatment. Results: Resistant cell lines to various kinds of EGFR-TKIs such as gefitinib, erlotinib, CL-387,785 and ZD6474 with A549, PC-9 and HCC827 lung adenocarcinoma cell lines were established. Among them, two resistant cell lines, A549/GR (resistant to gefitinib) and PC-9/ZDR (resistant to ZD6474) showed increased expressions of CD56 while increased synaptophysin, Rb, p16 and poly(ADP-ribose) polymerase were found only in A549/GR in western blotting, suggesting that NE differentiation occurred in A549/GR. A549/GR cells were more sensitive to etoposide and cisplatin, chemotherapeutic drugs for SCLC, compared to parental cells. Treatment with cAMP and IBMX induced synaptophysin and chromogranin A expression in A549 cells, which also made them more sensitive to etoposide and cisplatin than parental cells. Furthermore, we found a tissue sample from a patient which showed increased expressions of CD56 and synaptophysin after development of resistance to erlotinib. Conclusion: NE differentiation can occur during acquisition of resistance to EGFR-TKI, leading to increased chemosensitivity.

Background: Osteopontin (OPN) and carbonic anhydrase IX (CAIX), which are expressed on the surface of tumor cells, are associated with hypoxia during tumor development and progression. However, the roles of these proteins in the plasma of patients with non-small cell lung cancer (NSCLC) are poorly understood. Herein, we hypothesized that plasma OPN and CAIX levels could be used as diagnostic and prognostic tumor markers in patients with NSCLC. Methods: Fifty-three patients with NSCLC and 50 healthy control subjects were enrolled. We selected controls without malignancy and matched them with NSCLC patient cases according to age and gender. Blood samples were collected at the time of diagnosis; the plasma levels of OPN and CAIX were measured by enzyme-linked immunosorbent assays. Results: The plasma levels of OPN in the patients with NSCLC were significantly elevated as compared to those in the controls (p=0.016). However, there was no difference in the plasma level of CAIX between the NSCLC patients and controls. NSCLC patients with a distant metastasis had a remarkable increase in plasma OPN compared with patients without metastasis (p=0.026), but no such correlation was found for CAIX. There was no difference in overall survival rates according to the plasma level of OPN between the two groups (by Kaplan-Meier survival analysis). Conclusion: Plasma OPN levels were elevated in patients with NSCLC as compared with the controls, with greater elevation of OPN levels in the advanced stages of disease. Therefore, plasma OPN may have utility as a diagnostic, but not prognostic, biomarker of advanced NSCLC.

Although the relationship between malignancy risk with systemic sclerosis (SSc) has been inconclusive, there are some previous studies for a positive correlation. Most patients with SSc have some degree of lung parenchymal involvement in the form of interstitial thickening and fibrosis. Interstitial lung disease is the most common pulmonary manifestation of SSc. Interstitial lung disease following chemotherapy (5-fluorouracil, leucovorin, and oxaliplatin [FOLFOX]) is an uncommon life-threatening complication and it is induced by oxaliplatin. We report a case of multiple cancers in a patient with SSc and aggravated interstitial lung disease by chemotherapy.

Sarcoidosis, a systemic granulomatous disease of unknown etiology. The presentation of sarcoidal granuloma in neck nodes without typical manifestations of systemic sarcoidosis is difficult to diagnose. We describe the case of a 37-year-old woman with an increasing mass on the right side of neck. The excisional biopsy from the neck mass showed noncaseating epithelioid cell granuloma of the lymph nodes. No evidence of mycobacterial or fungal infection was noted. Thoracic evaluations did not show enlargement of mediastinal lymph nodes or parenchymal abnormalities. Immunohistochemistry showed abundant expression of tumor necrosis factor-${\alpha}$ in the granuloma. However, transforming growth factor-${\beta}$ was not expressed, although interleukin-$1{\beta}$ was focally expressed. These immunohistochemical findings supported characterization of the granuloma and the diagnosis of sarcoidosis. Sarcoidosis can present with cervical lymph node enlargement without mediastinal or lung abnormality. Immunohistochemistry may support the diagnosis of sarcoidosis and characterization of granuloma.

Herein, we report a case of multiple systemic arteries to pulmonary artery fistulas without any underlying causes, presenting recurrent hemoptysis. Transcatheter embolization was successfully performed several times on multiple systemic feeding arteries. Multiple systemic arteries to pulmonary fistulas can be a source of uncontrolled bleeding, and embolization may be a reasonable therapeutic option to control the bleeding.

In this paper, we describe 72-year-old female patient without evidence of malignant disease presented with significantly elevated serum carbohydrate antigen (CA) 19-9 levels by respiratory infections. She was diagnosed with respiratory infections due to Mycobacterium avium complex and Pseudomonas aeruginosa. The serum CA 19-9 levels remarkably increased (1,453-5,300 U/mL; reference range, <37 U/mL) by respiratory infection and abruptly decreased (357-534 U/mL) whenever infection was controlled by specific treatments. This case suggests that serum CA 19-9 levels may be used as a diagnostic marker to indicate new or resistant infections to previous antibiotics in chronic lung diseases without significant changes in chest X-ray findings.