Seung Taik Kim

EGFR Mutation Status in Primary Lung Adenocarcinomas and Corresponding Metastatic Lesions: Discordance in Pleural Metastases

UNLABELLED We evaluated EGFR and KRAS mutations between 37 paired primary tumors and corresponding metastases in lung adenocarcinoma. A substantial discordance was found in EGFR mutation status between primary tumors and corresponding metastases including pleural metastases. Moreover, the responsiveness to EGFR tyrosine kinase inhibitors tend to be correlated with EGFR mutation status in metastatic lesions than in primary tumors. INTRODUCTION The aim of this study was to compare epidermal growth factor receptor (EGFR) and KRAS mutations between primary tumors and corresponding metastases including pleural metastases in lung adenocarcinoma. METHODS Thirty-seven paired primary lung adenocarcinomas and corresponding metastatic tumors were analyzed for EGFR and KRAS mutations. In addition, 21 pleural metastases including malignant pleural effusion or pleural biopsy were used in performing these mutation analyses. RESULTS EGFR mutations were detected in 18 primary lung adenocarcinomas (48.6%) and in 16 corresponding metastases (43.2%). EGFR mutations showed a discordance rate of 16.2% (6 of 37 patients) between primary lung adenocarcinomas and corresponding metastases. Among 21 pleural metastases, 3 patients (14.3%) showed that the EGFR mutation was discordant. KRAS mutations were detected in one primary tumor and in two metastatic tumors. Eighteen patients were treated with EGFR tyrosine kinase inhibitors. One of seven patients who experienced partial response had EGFR mutations only in the metastasis, and two of seven patients who experienced progressive disease carried wild-type EGFR only in the metastasis. CONCLUSIONS EGFR mutations were discordant between primary tumors and corresponding metastases in a significant portion of lung adenocarcinomas. Furthermore, these discordance was also observed in metastases to the pleura, the nearest metastatic site.

Detection of EGFR Mutation Status in Lung Adenocarcinoma Specimens with Different Proportions of Tumor Cells Using Two Methods of Differential Sensitivity

Introduction: To evaluate epidermal growth factor receptor (EGFR) mutation status in lung adenocarcinoma specimens with different proportions of tumor cells using two methods with different sensitivities. Methods: EGFR mutation status was determined by peptide nucleic acid (PNA) clamping and direct sequencing. The samples consisted of 41 cell blocks of malignant pleural effusions with various proportions of tumor cells, as well as 23 lung biopsy specimens containing more than 20% tumor cells and the corresponding surgically resected tumors. Results: In the analysis of malignant pleural effusions, EGFR mutations were detected only by PNA clamping in four of nine patients who exhibited partial response to EGFR tyrosine kinase inhibitors; all the cell blocks of these four patients contained less than 20% tumor cells. Direct sequencing revealed wild-type EGFR, whereas PNA clamping revealed mutant EGFR, in one of five patients who exhibited progressive disease in response to EGFR tyrosine kinase inhibitor; the cell block of this patient contained a high proportion of tumor cells. A comparison of biopsy specimens containing sufficient tumor cells and the corresponding surgically resected tumors revealed discordance in the EGFR mutation status in four patients based on PNA clamping, whereas no discrepancies were observed by direct sequencing. Conclusions: Highly sensitive methods, such as PNA clamping, may be superior to direct sequencing for the detection of EGFR mutations in diagnostic specimens with a low proportion of tumor cells. Direct sequencing may be more representative when diagnostic specimens with a high proportion of tumor cells are available.

Plasminogen activator inhibitor‐1 is an independent diagnostic marker as well as severity predictor of hepatic veno‐occlusive disease after allogeneic bone marrow transplantation in adults conditioned with busulphan and cyclophosphamide

Summary. We attempted to identify the diagnostic markers and severity predictors of hepatic veno‐occlusive disease (VOD) in 115 adult patients who were uniformly conditioned with busulphan and cyclophosphamide and who underwent allogeneic bone marrow transplantation (BMT). A diagnosis of VOD was made according to clinical criteria. Severity of VOD was classified as mild, moderate or severe. Various haemostatic parameters were determined at five time points (d −7, 0, 7, 14 and 21). Using clinical and haemostatic parameters, we developed multivariate models to identify diagnostic markers as well as severity predictors of VOD. Of the 115 patients included in the study, 50 (43·5%) developed VOD. Twenty‐nine had mild VOD, 13 moderate and 8 severe. Multiple logistic regression models showed that plasminogen activator inhibitor‐1 (PAI‐1) antigen (P = 0·029), percentage change of body weight (P = 0·001) and bilirubin (P < 0·001) were independent marker variables for the occurrence of VOD, and PAI‐1 antigen (P = 0·030) and bilirubin (P = 0·049) were independent marker variables for the occurrence of severe VOD. Our study suggests that PAI‐1 antigen can be used as a diagnostic marker as well as a severity predictor of VOD after allogeneic BMT.

Downregulation of cell-free miR-198 as a diagnostic biomarker for lung adenocarcinoma-associated malignant pleural effusion.

Circulating cell‐free microRNAs (miRNAs) are potential cancer biomarkers. The aim of this study was to identify miRNAs that are differentially expressed between benign pleural effusion (BPE) and lung adenocarcinoma‐associated malignant pleural effusion (LA‐MPE). The expression level of cell‐free miRNA was investigated in 107 patients with pleural effusion. Microarrays were used to screen 160 miRNAs in a discovery set comprising 20 effusion samples (ten BPEs and ten LA‐MPEs). Real‐time quantitative reverse transcription polymerase chain reaction (qRT‐PCR) was used to validate the profiling results obtained for the discovery set and those obtained for a validation set comprising 42 BPEs and 45 LA‐MPEs. The area under the receiver operating characteristic curve (AUC) was used to evaluate the diagnostic performance of the identified miRNAs and other common tumor markers, such as carcinoembryonic antigen (CEA) and cytokeratin fragment (CYFRA) 21‐1. Microarray profiling showed that miR‐198 was significantly downregulated in LA‐MPE compared with BPE (p = 0.002). The miRNA microarray analysis results were confirmed by qRT‐PCR (p < 0.001) using the validation set. The AUCs for miR‐198, CEA and CYFRA 21‐1 in the validation set were 0.887, 0.898 and 0.836, respectively. The diagnostic performance of miR‐198 was comparable with that of CEA, but better than that of CYFRA 21‐1. The AUC for all three markers combined was 0.926 (95% confidence interval, 0.843–0.973) with a sensitivity of 89.2% and a specificity of 85.0%. The present study suggests that cell‐free miR‐198 from patients with pleural effusion might have diagnostic potential for differentiating LA‐MPE from BPE.

Correction of anemia in uremic rats by intramuscular injection of lentivirus carrying an erythropoietin gene

Background: Anemia is an inevitable consequence of chronic renal failure. Gene therapy using lentiviral vector (LV) would be an effective tool to treat anemia associated with renal failure. Methods: A LV carrying the erythropoietin (EPO) cDNA was administered to skeletal muscle of partially nephrectomized rats, which is a model of uremia. The red blood cell production and serum EPO levels were temporally monitored in these rats. Polymerase chain reaction assays were done to validate the presence of the LV in the experimental rats. Results: After a single intramuscular injection of LV at a dose of 55 µg p24 Gag antigen (∼5 × 107 transducing units), blood hematocrit (Hct) levels increased and peaked at 3 weeks (47.8 ± 4.2%, p < 0.01, n = 8) with the levels being maintained for at least 20 weeks (duration of study; 44.9 ± 3.3%, p < 0.01, n = 3). The control rats receiving LV expressing lacZ had Hct levels of 36.9 ± 4.1% (n = 8) at 3 weeks and 33.1 ± 3.7% (n = 4) at 20 weeks, respectively. The serum EPO levels in the rats injected with the LV expression EPO significantly increased (p < 0.01) to 156.3 ± 3.0 mU/ml compared to the control rats (63.9 ± 1.7 mU/ml). Polymerase chain reaction analysis of the isolated genomic DNA from the LV-injected rats showed specific positive detection of the LV in only the skeletal muscle tissue at the site of injection, whereas the other tissues, including the liver, spleen, and kidney, were negative. Conclusions: This study demonstrates that intramuscular injection of LV can produce highly efficient and sustained EPO secretion in uremic rats, and suggests that this approach could be an effective tool to deliver secretable proteins at therapeutic levels in various animal disease models.

Pneumatosis intestinalis and portal venous gas secondary to Gefitinib therapy for lung adenocarcinoma

BackgroundPneumatosis intestinalis (PI), defined as the presence of gas in the bowel wall, and portal venous gas (PVG) are relatively rare radiological findings. Although several chemotherapeutic agents and anti-vascular endothelial growth factor agents are reported to be associated with PI and PVG, an association with anti-epidermal growth factor receptor (EGFR) agents has not been described previously.Case presentationThe present report describes a case of PI and PVG secondary to treatment with an EGFR tyrosine kinase inhibitor. A 66-year-old woman who had been diagnosed with metastatic lung adenocarcinoma presented with nausea, vomiting and abdominal distension after commencing gefitinib. A computed tomography (CT) scan of the abdomen revealed PI extending from the ascending colon to the rectum, hepatic PVG, and infarction of the liver. Gefitinib therapy was discontinued immediately and the patient was managed conservatively. A follow-up CT scan 2 weeks later revealed that the PI and hepatic PVG had completely resolved.ConclusionThis is the first report of PI and PVG caused by EGFR tyrosine kinase inhibitor. Although these complications are extremely rare, clinicians should be aware of the risk of PI and PVG in patients undergoing targeted molecular therapy.

Extranodal Interdigitating Dendritic Cell Sarcoma Presenting in the Pleura: A Case Report

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare neoplasm arising from the antigen-presenting cells of the immune system. This disease usually involves the lymph nodes, and rarely, extranodal sites may be affected. The authors report a case of extranodal IDCS presenting in the pleura. A 32-yr-old man presented with progressive chest pain. Imaging studies showed diffuse pleural thickening with pleural effusion. Morphological and immunohistochemical analysis of an incisional biopsy of the pleura were consistent with a diagnosis of IDCS; tumor cells were positive for S100 and CD45, but negative for CD1a, CD21, CD35, B cell and T cell markers. The patient was administered chemotherapy, but died of progressive disease. Although its incidence is extremely rare, this case suggests that extranodal IDCS should be considered in the differential diagnosis of undifferentiated neoplasms and that immunohistochemical staining be performed using appropriate markers.

Korean patients with superwarfarin intoxication and their outcome.

This observational study aimed at evaluating recent superwarfarin intoxication of Korean patients. Ten patients were diagnosed as or highly suspicious for superwarfarin intoxication. Case report forms described by attending hematologists of the patients were collected and analyzed. Bleeding symptoms were varied among the patients. Patients uniformly showed prolonged prothrombin time (PT) and activated thromboplastin time (aPTT) with decreased activity of vitamin K dependent coagulation factors. Positive serum brodifacoum test results in 4 of 5 requested patients contributed to confirmatory diagnosis. Psychiatric interview revealed an attempted ingestion in one patient. High dose vitamin K1 therapy promptly corrected prolonged PT and aPTT, but hasty discontinuation caused repeated bleeding diathesis in 6 patients. Route of intoxication was unknown or not definite among 8 of 10 patients. Three patients had a possibility of environmental exposure considering their occupations: there might be intoxication by transdermal absorption or inhalation. Therefore, high dose and prolonged use of vitamin K1 therapy is necessary for effective detoxification. Further detailed investigation on environmental exposure and efforts to improve availability of the blood level test in clinic are requested.

Delivery of Factor VIII Gene into Skeletal Muscle Cells Using Lentiviral Vector

Purpose This study was designed to investigate whether transduction of lentiviral vectors (LV) carrying human coagulation factor VIII (hFVIII) cDNA into skeletal muscle could increase circulating hFVIII concentrations. Materials and Methods A LV containing bacterial LacZ gene as a control or human FVIII gene was intramuscularly administered into the thigh muscle of 5 weeks old Sparague-Dawley rats. The plasma human FVIII concentration and neutralizing anti-FVIII antibodies were measured for up to 12 weeks in these experimental animals. Results The plasma human FVIII levels in the rats injected with LV carrying FVIII cDNA peaked at post-injection 1st week (5.19 ± 0.14 ng/mL vs. 0.21 ± 0.05 ng/mL in control rats , p < 0.05). Elevated hFVIII concentrations were maintained for 4 weeks (2.52 ± 0.83 ng/mL vs. 0.17 ± 0.08 ng/mL in control rats, p < 0.05) after a single intramuscular injection. In the Bethesda assay, neutralizing antibodies for FVIII protein were detected only in FVIII-LV injected rats by the 10th week, but not in control rats. Conclusion This study suggested that a single administration of an advanced generation LV carrying the human FVIII cDNA resulted in elevation of FVIII level in immune competent rats, and that this gene transfer approach to the skeletal muscle could be an effective tool in treatment of hemophilia A.

Metastatic Renal Cell Carcinoma in a Supraclavicular Lymph Node with No Known Primary: A Case Report

Although metastasis is relatively frequent in cases of renal cell carcinoma (RCC), metastasis in the cervical or supraclavicular lymph node (LN) is relatively rare. Moreover, cases of metastatic RCC with a non-identifiable kidney mass are extremely rare. Here, the authors report a case of metastatic RCC in a supraclavicular LN without a primary kidney lesion. A 69-year-old man presented with a progressively enlarging right supraclavicular mass. Incisional biopsy of the affected supraclavicular LN was performed, and histological examination revealed metastatic RCC. However, no tumor was found in either kidney, despite various examinations. The patient was treated with radiotherapy followed by sunitinib. After three months on sunitinib, a follow-up computed tomography scan revealed that the supraclavicular LN had markedly decreased, and after 20 months, the disease had not progressed. This case suggests that, even when there is no primary kidney lesion, clinicians must consider the possibility of metastatic RCC when evaluating patients with clear cell carcinoma with an unknown primary site.