Diffuse pleural thickening and thoracic contraction: An indistinguishable case from malignant pleural mesothelioma.

The differential diagnosis of reactive mesothelial hyperplasia and mesothelioma is difficult. We present a rare case of diffuse pleural thickening with thoracic contraction that was indistinguishable from mesothelioma. A 66-year-old woman with no history of asbestos exposure visited our hospital with a complaint of dyspnea. The clinical findings included circumferential pleural thickening on chest computed tomography image and a high concentration of hyaluronic acid in the pleural fluid. Pleural biopsies obtained by thoracoscopy under local anesthesia were pathologically consistent with mesothelioma, but the patient refused to take any kind of mesothelioma treatments. Four months later, she consented to a surgical pleural biopsy under general anesthesia to obtain larger tissue samples, which included typical proliferating polygonal cells positive for CAM5.2, calretinin, WT-1, D2-40, CK5/6, epithelial membrane antigen, and glucose transporter-1 and negative for carcinoembryonic antigen, BerEP4, and MOC31. The analysis was consistent with diagnosis of epithelioid mesothelioma. Fluorescence in situ hybridization, however, showed the presence of p16 gene, and the expression of BRCA1-associated protein-1 was detected by immunohistochemistry. Our final diagnosis was diffuse pleural thickening unrelated to asbestos exposure. Differential diagnosis of diffuse pleural thickening and malignant mesothelioma is thus difficult and routine immunohistochemical examinations are often insufficient for accurate diagnosis. Multiple diagnostic methods are required for correct diagnosis in a clinically marginal case.

Multidetector-row computed tomography management of acute pulmonary embolism.

BACKGROUND: The purpose of this study was to evaluate the usefulness and safety of multidetector-row computed tomography (MDCT) pulmonary angiography and indirect venography management of acute pulmonary embolism (PE), including indication for inferior vena cava (IVC) filter. METHODS AND RESULTS: Seventy-one consecutive patients who were clinically suspected of PE and underwent 16-slice MDCT pulmonary angiography and indirect venography were enrolled. Management included indication of IVC filter for patients with extensive deep venous thrombosis (DVT) in submassive or massive PE. A right ventricular to left ventricular short-axis diameter by MDCT>1.0 was judged as submassive PE. All patients were followed for 1 year. MDCT identified 50 patients with venous thromboembolism and 47 patients had acute PE: 4 were judged as massive, 14 as submassive, and 29 as non-massive by MDCT; 3 patients had DVT alone and 7 patients had caval or iliac DVT. Only 1 patient with massive PE and DVT near the right atrium died of recurrence. No other patients died of PE. CONCLUSION: Management based on MDCT pulmonary angiography combined with indirect venography is considered to be safe and reliable in patients with suspected acute PE.

Altered gene expression by cisplatin in a human squamous cell lung carcinoma cell line.

BACKGROUND: Substantial evidence has disclosed that some cytotoxic agents have complex activities in influencing signal transduction pathways in cells. MATERIALS AND METHODS: cDNA microarray analysis was performed after exposing a human squamous cell carcinoma cell line, RERF-LC-AI, to low-dose cisplatin for 5 days. Up-regulated gene expressions were suppressed by small interfering RNA to investigate phenotypic alteration of the cells. RESULTS: Among 30,000 genes screened, 42 genes showed increases or decreases in expression of more than 2-fold with cisplatin treatment. They included genes with functions involved in apoptosis, cell cycle regulation and DNA metabolism/repair. Suppression of the 5 most significantly altered genes by small interfering RNA resulted in partly reduced apoptosis without altering cytotoxicity of cisplatin. CONCLUSION: Besides direct cytotoxic effects on cells, cisplatin may have indirect effects involving drug resistance, and synergistic effects with other agents.

Effect of treatment schedule on the interaction of Cisplatin and radiation in human lung cancer cells.

This study was designed to determine the effects of the treatment schedule on the interaction between cisplatin and radiation. Cells of a human squamous cell lung cancer cell line were treated with cisplatin and radiation using three treatment protocols: 1-h exposure to cisplatin immediately followed by irradiation (A), 4-day continuous exposure to cisplatin immediately followed by irradiation (B), and 1-h exposure to cisplatin followed by irradiation after a 4-day interval (C). The interactions were assessed by isobologram, cell cycle distribution and apoptosis. The combination resulted in a additive effect in every protocol. Cell cycle accumulation at G(2)/M phase before irradiation was observed in Protocols B and C, whereas no cell cycle shift in the limited time course was noted in Protocol A. Although a 4-day continuous exposure to cisplatin and a 1-h exposure to cisplatin followed by a 4-day interval before irradiation caused significantly increased apoptosis, an additional increase in apoptosis after irradiation was not observed in Protocols B and C, whereas Protocol A showed an additional increase. Despite a cell cycle shift favoring radiation sensitivity, the drug-radiation interactions in Protocols B and C were additive, possibly because of negative effects including induction of a durable G(2)/M-phase arrest and suppression of apoptosis by cisplatin.

Sequential gene expression changes in cancer cell lines after treatment with the demethylation agent 5-Aza-2'-deoxycytidine.

BACKGROUND: 5-Aza-2'-deoxycytidine (5-AzaC) is known well for its demethylation effect and is a promising anticancer agent. However, to the authors' knowledge, serial changes in gene expression over time after 5-AzaC treatment have not been studied to date. To clarify the categories of genes that are up-regulated or down-regulated after 5-AzaC treatment, the authors surveyed the genes that had expression levels changed by 5-AzaC treatment in 6 hepatoma cell lines (Hep3B, HLE, Huh7, HepG2, PLC/PRF/5, and Huh6). METHODS: Cell lines were grown in medium that contained 1 microM of 5-AzaC. Changes in messenger RNA levels were monitored from 24 hours up to 120 hours after 5-AzaC treatment using an in-house microarray that consisted of 4608 combinational DNAs. Using clustering analysis to identify the genes that had gradually changed expression levels and to exclude the substantial experimental noise by microarray analysis, the authors focused on 206 up-regulated genes and 248 down-regulated genes. RESULTS: According to their functional characterization, genes that were involved in the cytoskeleton and the extracellular matrix were enriched significantly in the up-regulated genes. Conversely, genes that were involved in metabolism were enriched significantly in the down-regulated genes. CONCLUSIONS: The current results demonstrated that 5-AzaC can regulate the expression of groups of genes with characteristic functions.

Basaloid squamous-cell carcinoma of the lung in a young woman.

We report a rare case of basaloid squamous cell carcinoma of the lung in a young Japanese woman. An 18-year-old woman presented with productive cough. Chest radiogram and computed tomography (CT) revealed a tumor in the left hilum accompanied by partial atelectasis of the left upper lobe and pleural effusion. Transbronchial fine-needle aspiration cytology supported a tentative diagnosis of primary squamous-cell carcinoma of the lung. The clinical stage was T4N2M1, with multiple bone metastases. Despite a transient response to chemotherapy consisting of carboplatin and paclitaxel, the patient died because of tumor progression 2 months after the start of the chemotherapy. Necropsy established the diagnosis of basaloid squamous-cell carcinoma of the lung. Immunohistochemical studies of the necropsy specimen indicated that the tumor was positive for keratin, vimentin, and S100, and negative for chromogranin A, cytokeratin CAM5.2, and bcl-2. Besides the rarity of the disease itself, the present case seemed to have additional uniqueness in that the patient was 18 years old and female. This is the youngest patient with a case of basaloid squamous cell carcinoma of the lung ever reported.

[A case of fatal MALT lymphoma of pulmonary origin with systemic metastasis and manifesting macroglobulinemia].

The patient was a 61-year-old man whose chest radiography showed infiltration in both lung fields. MALT lymphoma was diagnosed from transbronchial lung biopsy (TBLB) specimens. The serum monoclonal IgM level then increased, and plasma cells and lymphoplasmacytoid cells were found in a bone marrow examination, indicating macroglobulinemia as a complication. Despite chemotherapy, systemic metastasis led to the patient's death. Our report is accompanied with a review of literature, because no report of MALT lymphoma of pulmonary origin complicated with macroglobulinemia exists, and it is considered that the macroglobulinemia in this case was related to the MALT lymphoma.