Ho-chang Lee

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.

Diagnostic performance of CD66c in lung adenocarcinoma-associated malignant pleural effusion: comparison with CEA, CA 19-9, and CYFRA 21-1.

Summary Various tumour markers have been evaluated in malignant pleural effusions, but not CD66c. This study evaluated the diagnostic ability of CD66c in lung adenocarcinoma-associated malignant pleural effusions (LA-MPEs) and compared it with other known tumour markers. Forty-seven cases of LA-MPE and 52 cases of benign pleural effusions were collected. The levels of CD66c, CEA, CA 19-9, and CYFRA 21-1 were measured by enzyme immunoassay. The expression of CD66c, CEA, and CA 19-9 in cell blocks was measured by immunocytochemistry. CEA had the best diagnostic values, with a sensitivity of 87.2% and specificity of 92.3%. Both CD66c and CA 19-9 showed the highest specificity of 98.1%, with sensitivities of 63.8% and 55.3%, respectively. CYFRA 21-1 had a sensitivity of 83.0% and specificity of 76.9%. CEA combined with CA 19-9 reached a sensitivity of 91.5% and a specificity of 98.1%. The sensitivities of immunocytochemical staining for CD66c, CEA, and CA 19-9 were 72.5%, 75%, and 40%, respectively. CD66c showed a diagnostic performance comparable to CYFRA 21-1 and CA 19-9 by enzyme immunoassay. Immunocytochemical study showed that CD66c and CEA were more sensitive than CA19-9. Both studies support CD66c as a potential tumour marker to differentiate LA-MPE from benign effusions.

Comparison of diagnostic accuracy between CellprepPlus® and ThinPrep® liquid‐based preparations in effusion cytology

Liquid‐based cytology (LBC) is being increasingly used for body fluid specimens and has improved diagnostic accuracy when compared to conventional smears. We compared the diagnostic accuracy and cellular morphologic features between CellprepPlus® LBC and ThinPrep® LBC in effusion cytology.

Novel monoclonal antibody against beta 1 integrin enhances cisplatin efficacy in human lung adenocarcinoma cells

Abstract The use of anti-beta 1 integrin monoclonal antibody in lung cancer treatment has proven beneficial. Here, we developed a novel monoclonal antibody (mAb), called P5, by immunizing mice with human peripheral blood mononuclear cells (PBMC). Its anti-tumor effect is now being tested, in a clinical phase III trial, in combinatorial treatments with various chemical drugs. To confirm that P5 indeed binds to beta 1 integrin, cell lysates were immunoprecipitated with commercial anti-beta 1 integrin mAb (TS2/16) and immunoblotted against P5 to reveal a 140 kDa molecular weight band, as expected. Immunoprecipitation with P5 followed by LC/MS protein sequence analysis further verified P5 antigen to be beta 1 integrin. Cisplatin treatment upregulated cell surface expression of beta 1 integrin in A549 cells, while causing inhibition of cell growth. When cells were co-treated with different concentrations of P5 mAb, the cisplatin-mediated inhibitory effect was enhanced in a dose-dependent manner. Our findings show that a combinatorial treatment of P5 mAb and cisplatin in A549 cells resulted in a 30% increase in apoptosis, compared to baseline, and significantly more when compared to either the cisplatin or P5 alone group. The entire peptide sequences in CDR from variable region of Ig heavy and light chain gene for P5 mAb are also disclosed. Together, these results provide evidence of the beneficial effect of P5 mAb in combinatorial treatment of human lung adenocarcinoma.

Generation of 1E8 Single Chain Fv-Fc Construct Against Human CD59.

Background Therapeutic approaches using monoclonal antibodies (mAbs) against complement regulatory proteins (CRPs:i.e.,CD46,CD55 and CD59) have been reported for adjuvant cancer therapy. In this study, we generated a recombinant 1E8 single-chain anti-CD59 antibody (scFv-Fc) and tested anti-cancer effect.by using complement dependent cytotoxicity (CDC). Methods We isolated mRNA from 1E8 hybridoma cells and amplified the variable regions of the heavy chain (VH) and light chain (VL) genes using reverse-transcriptase polymerase chain reaction (RT-PCR). Using a linker, the amplified sequences for the heavy and light chains were each connected to the sequence for a single polypeptide chain that was designed to be expressed. The VL and VH fragments were cloned into the pOptiVEC-TOPO vector that contained the human CH2-CH3 fragment. Then, 293T cells were transfected with the 1E8 single-chain Fv-Fc (scFv-Fc) constructs. CD59 expression was evaluated in the prostate cancer cell lines using flow cytometry. The enhancement of CDC effect by mouse 1E8 and 1E8 scFv-Fc were evaluated using a cytotoxicity assay. Results The scFv-Fc constructs were expressed by the transfected 293T cells and secreted into the culture medium. The immunoreactivity of the secreted scFv-Fc construct was similar to that of the mouse 1E8 for CCRF-CEM cells. The molecular masses of 1E8 scFv-Fc were about 120 kDa and 55 kDa under reducing and non-reducing conditions, respectively. The DNA sequence of 1E8 scFv-Fc was obtained and presented. CD59 was highly expressed by the prostate cancer cell line. The recombinant 1E8 scFv-Fc mAb revealed significantly enhanced CDC effect similar with mouse 1E8 for prostate cancer cells. Conclusion A 1E8 scFv-Fc construct for adjuvant cancer therapy was developed.

Positive Response to Trastuzumab in a Case of HER2-Overexpressing Metastatic Gastric Cancer that Presented as Severe Thrombocytopenia

Background: Trastuzumab, a humanized monoclonal antibody directed against human epidermal growth factor receptor 2 (HER2), has been shown to be active against metastatic gastric cancers that overexpress HER2. Case Report: A 47-year-old man presented with a headache and visual disturbance. He was subsequently found to have an intracranial hemorrhage. Laboratory testing showed severe thrombocytopenia, and a bone marrow biopsy revealed aggregates of malignant tumor cells. Endoscopic biopsy of an ulcerative lesion of the gastric antrum confirmed signet ring cell carcinoma based on the results of H&E staining. Immunohistochemistry of the tumor cells revealed HER2 overexpression with an intensity of 3+, and silver in situ hybridization showed HER2 gene amplification. The patient was treated with trastuzumab because of the presence of severe thrombocytopenia. After 2 months of trastuzumab therapy, gastric wall thickening and ascites were diminished and thrombocytopenia was markedly improved. Trastuzumab was continued for an additional 3 months. Conclusion: This is the first report of a positive response to trastuzumab in a patient with HER2-overexpressing metastatic gastric cancer that was accompanied by bone marrow involvement and severe thrombocytopenia. This finding is of considerable relevance for difficult cases of metastatic gastric cancer that preclude the administration of aggressive antineoplastic regimens.

Diagnostic benefits of the combined use of liquid-based cytology, cell block, and carcinoembryonic antigen immunocytochemistry in malignant pleural effusion

Background Malignant pleural effusion (MPE) is a common complication of cancer cell metastasis to the pleura. Discrimination between MPE and benign pleural effusion is necessary to design treatment strategies. Cytology is important for the diagnosis of MPE. Carcinoembryonic antigen (CEA) is an epithelial biomarker with a strong staining pattern in adenocarcinomas. Here, the diagnostic performances of liquid-based cytology (LBC), cell block (CB) preparation, and CEA immunostaining for the detection of malignancy in effusion cytology were compared in a large case series. Methods In a single institution, 1,014 cytology samples from 862 patients were retrospectively collected and reviewed between January 2013 and November 2015. Ethanol-fixed, paraffin embedded CB of pleural effusions was analyzed by CEA immunostaining. Diagnostic values were compared among LBC, CB, CEA immunostaining, and the combination of two methods. Results The sensitivity and specificity of the CB preparation were 94.3% and 98.7%, respectively, compared with 81.3% and 99.4% for LBC preparations, respectively. Combination of LBC and CB increased sensitivity by 98.3%. Although the accuracy of CEA staining itself was moderate (sensitivity, 89.8%), the combined use of CB and CEA tumor marker increased the detection rate of malignancy (sensitivity, 100%; specificity, 100%), compared with that of cytology (LBC or CB) alone. Conclusions The sensitivity and specificity for the diagnosis of MPE could be improved by integrating the CB and CEA staining into LBC in routine clinical practice to improve diagnostic accuracy.

Extra-articular tenosynovial giant cell tumor of diffuse type in the temporal area with brain parenchymal invasion: a case report

Abstract Tenosynovial giant cell tumor of diffuse type is a locally aggressive neoplasm that most commonly arises in the lower extremities. Herein, we report for the first time a case of an extra-articular tenosynovial giant cell tumor of diffuse type in the temporal region with brain parenchymal invasion. Imaging studies revealed an intracranial expansile mass in the temporal bone without involvement of the temporomandibular joint. The unusual location of the tumor without involvement of the joint and the presence of brain parenchymal invasion made this case challenging to diagnose.

Synchronous double primary renal cell carcinoma and duodenal adenocarcinoma

ogy, the incidence of double primary cancer is increasing. In case that one primary cancer was identified by pathologic finding and has suggestive multiple metastatic lesions of the cancer, it is often difficult that the lesions are considered as another synchronous primary malignancy, not as metastasis of primary cancer. Here, we report a rare case of synchronous double primary renal cell carcinoma that was diagnosed initially as metastatic duodenal adenocarcinoma. A 66-year-old man presented with a palpable abdominal mass. Abdominal computed tomography showed duodenal wall thickening and hypervascular masses in the liver and left kidney. Esophagogastroduodenoscopy revealed an ulcerative lesion in the duodenal bulb, and endoscopic biopsy identified moderately-differentiated adenocarcinoma. We regarded the findings as duodenal adenocarcinoma with metastasis to liver and kidney. So he was treated with fluoropyrimidine-based chemotherapy for the diagnosis of duodenal adenocarcinoma with liver and renal metastases. After 10 months, he developed a right forearm mass. Morphological and immunohistochemical analysis of an incisional biopsy of the forearm mass were consistent with a diagnosis of metastatic renal cell carcinoma. Even when there is a pathologically confirmed malignancy, clinicians must consider the possibility of synchronous double primary malignancy in metastatic lesions.