Publications by authors named "John Kwok-Cheung Chan"

Background: Cell free RNA (cfRNA) contains transcript fragments from multiple cell types, making it useful for cancer detection in clinical settings. However, the pathophysiological origins of cfRNAs in plasma from colorectal cancer (CRC) patients remain unclear.

Methods: To identify the tissue-specific contributions of cfRNAs transcriptomic profile, we used a published single-cell transcriptomics profile to deconvolute cell type abundance among paired plasma samples from CRC patients who underwent tumor-ablative surgery.

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Background: Colorectal cancer (CRC) is the second leading cause of cancer deaths in Hong Kong. We tested the hypothesis that circulating tumor cell (CTC) analysis by ARB101 antibody could be used as a tool for CRC detection, progression, and therapy response.

Research Methods: ARB101 antibody was used for investigation of CDH17 expression in formalin-fixed, paraffin-embedded (FFPE) tissue sections and circulating tumor cells (CTCs) of CRC patients.

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Background: Cytokeratin 20-positive cells in lymph nodes from pN0 colorectal cancer (CRC) patients were detected previously by us. The aims of this study were to investigate which tumor metastasis-related genes were involved and their potential clinical significance.

Results: Fourteen of 84 (17%) genes were differentially expressed by at least 2-fold.

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Aims: The vast majority of type A thymomas are diagnosed in tumour stages 1 or 2, and metastatic cases are exceedingly rare. The histological and genetic features of such metastatic type A thymomas have not been described in detail.

Methods And Results: Five metastatic type A thymomas in tumour stage Masaoka IVb that had been reviewed by a panel of expert pathologists were analysed using comparative genomic hybridization (CGH).

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Thymic neuroendocrine tumors (TNET) are rare primary epithelial neoplasms of the thymus. This study aimed to determine clinically relevant parameters for their classification and for therapeutic decisions. We performed a comprehensive histological, clinical, and genetic study of 73 TNET cases (13 thymic typical carcinoids [TTC], 40 thymic atypical carcinoids [TAC], and 20 high-grade neuroendocrine carcinomas [HGNEC] of the thymus), contributed by multiple institutions.

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China is undergoing a recent outbreak of a novel H7N9 avian influenza virus (nH7N9) infection that has thus far involved 132 human patients, including 37 deaths. The nH7N9 virus is a reassortant virus originating from the H7N3, H7N9 and H9N2 avian influenza viruses. nH7N9 isolated from humans contains features related to adaptation to humans, including a Q226L mutation in the hemagglutinin cleavage site and E627K and D701N mutations in the PB2 protein.

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Micrometastases in lymph nodes and blood may provide important prognostic information. In this study, cytokeratin 20 (CK20) positive cells in lymph nodes and circulating CK20 mRNA were studied using 57 paraffin-embedded lymph node specimens and blood from 24 patients with pN0 colorectal cancer (CRC), respectively. Results showed that 29 out of 56 (52%) lymph node specimens had CK20-positive cells (range: 1-35).

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Background: Systemic anaplastic large cell lymphoma (ALCL) is predominantly a nodal disease, but extranodal involvement can occur during the disease course or as the primary presentation. We report two rare cases of ALCL presenting with a pleural effusion, mimicking primary effusion lymphoma (PEL).

Cases: Two patients, a 47-year-old woman and an 81-year-old man, presented with a pleural effusion for investigation.

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Aberrant methylation of promoter CpG regions is a putative mechanism whereby tumor suppressor genes are inactivated. We used a candidate gene approach to investigate the patterns and significance of this epigenetic change in natural killer (NK) cell malignancies. Thirty-three patients were studied for promoter methylation in five putative tumor suppressor genes by methylation-specific polymerase chain reaction (MSP), which has a sensitivity of 10(-3).

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