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Biomedical subjects

G C Ooi

Publications and source records attributed to G C Ooi.

At least 55 records · Page 3Linked to original sources
PubMed2002

Computed tomography characteristics of advanced primary pulmonary lymphoepithelioma-like carcinoma.

Our objectives were to document CT features of advanced primary pulmonary lymphoepithelioma-like carcinoma (LELC) and to determine features that may assist differentiation from other non-small cell lung cancers (NSCLC). Imaging and clinical data of all patients with biopsy-proven pulmonary LELC ( n=12) were retrieved from a database of all NSCLC patients over a 2-year period. Twenty-five controls were recruited from other inoperable non-LELC NSCLC patients from the database. Pre-treatment CT scans of the thorax of both study and control patients were reviewed for lobe involved; tumour site, borders and size; and pleural, vascular or pulmonary involvement. Presence of lymphangitis carcinomatosis was noted. Lymph node metastasis was characterised as ipsilateral or contralateral enlarged (>1 cm) mediastinal or hilar nodes, or as peribronchovascular nodal spread. Differences between the two groups were tested using Mann-Whitney rank-sum test. The LELC tumours were significantly larger (45.67 vs 17.71 cm(2)) than controls and were closely associated with the mediastinum. There were more LELC tumours with well-defined borders ( p<0.001) and fewer with spiculated borders ( p<0001) than non-LELC tumours. There was increased peribronchovascular nodal spread ( p=0.01) and vascular encasement ( p=0.02) in LELC compared with non-LELC tumours. Advanced primary pulmonary LELC has distinct radiological features, and can appear as well-defined tumour closely associated with the mediastinum, with peribronchovascular spread and vascular encasement.

Adenocarcinoma↗
PubMed2002

Pulmonary iron overload in thalassemia major presenting as small airway disease.

Lung function abnormalities that are associated with thalassemia major are variable with etiology that is yet undetermined. Some studies have suggested that pulmonary iron deposition is a probable cause for these lung defects although there has been no antemortem histopathological and radiological evidence for this. We report a case of thalassemia major with biopsy-proven pulmonary iron overload, in which thoracic high-resolution computed tomography revealed a morphological-functional correlation consistent with small airway disease.

Adult↗
PubMed2002

Overexpression of matrix metalloproteinase-8 and -9 in bronchiectatic airways in vivo.

The progressive bronchial dilatation in bronchiectasis is likely to be the result of continued airway matrix destruction, although little is known about the role of neutrophil matrix metalloproteinases (MMPs) in this process. Immunohistochemistry has been used to investigate the expression and cellular localisation of MMP-8 and MMP-9 in bronchiectatic airways in vivo. Endobronchial biopsies were taken from 25 bronchiectatic patients, and from the right lower lobe in 14 control subjects. MMP-8, MMP-9, neutrophils and macrophages were stained with monoclonal antibodies and quantified as positive cell x mm(-2) of the lamina propria by using an image analysis system. There were significantly higher densities of MMP-8 and MMP-9 positive cells in the lamina propria of bronchiectatic than control airways. In bronchiectatic airways, the densities of MMP-8 and MMP-9 positive cells correlated with each other and with neutrophil density, but not with macrophage density. In control airways, a significant correlation was found between MMP-8 with neutrophil and MMP-9 with macrophage densities. An overexpression of neutrophil matrix metalloproteinases in bronchiectatic airways could help explain the continuation of airway destruction in bronchiectasis. In view of the clinical availability of matrix metalloproteinase antagonists, the results presented here could have a significant impact on the development of novel therapies of this untreatable disease.

Aged↗
PubMed2001

Pulmonary sequelae of treatment for breast cancer: a prospective study.

PURPOSE: To prospectively study the effects of loco-regional radiotherapy in women with breast cancer. METHODS AND MATERIALS: Thirty consecutive patients with breast resection underwent clinical, lung function, radiographic, and thoracic high-resolution computed tomography evaluation before and at 1, 3, 6, and 12 months after adjuvant radiotherapy. Chemotherapy was also administered to 15 patients. RESULTS: Nineteen patients reported mild respiratory symptoms at 1 month, which resolved completely at 6 months after radiotherapy. Opacities were present on 80% of chest radiographs and in all patients on high-resolution computed tomography by 3 months. These opacities became compact and persisted on high-resolution computed tomography at 12 months. Lung function indices, including FEV1, FVC, TLC, and DLCO, progressively declined after radiotherapy, and was irreversible at 12 months (p < 0.05). Patients who received chemotherapy did not have significantly different lung function indices compared with their counterparts at all time points (p > 0.05). CONCLUSIONS: Our results have shown that adjuvant loco-regional radiotherapy, a common practice in breast cancer treatment, is associated with irreversible reduction in lung function parameters. These changes are accompanied by radiological evidence of persistent lung injury. Further studies should be performed to evaluate the incidence and long-term pulmonary sequelae of current treatment for breast cancer.

Adult↗
PubMed2001

Pulmonary cryptococcosis: a case report and review of the Asian-Pacific experience.

Pulmonary cryptococcosis is a very rare form of pneumonia, which is seldom seen among immunocompetent patients. We report the case of a 36-year-old man who presented with indolent pneumonia that was subsequently diagnosed to be pulmonary cryptococcosis without other systemic involvement. Contrary to formal belief, there was evidence of residual lung fibrosis 12 months after initial presentation. The features of pulmonary cryptococcosis reported in the Asian Pacific region are also reviewed.

Adult↗
PubMed2001

Macrophages, neutrophils and tumour necrosis factor-alpha expression in bronchiectatic airways in vivo.

Bronchiectasis is increasingly being recognized as an inflammatory condition of the airways in which pathological permanent dilation occurs. We have obtained endobronchial biopsies in 14 patients with stable bronchiectasis and 15 control subjects. Airway neutrophils, macrophages and tumour necrosis factor-alpha (TNFalpha)-positive cells were stained with monoclonal antibodies and the densities of positive cells in the lamina propria were determined by using a computer image analyser. There was significantly higher neutrophil, macrophage and TNFalpha-positive cell densities in the lamina propria of bronchiectatic than control airways (P < 0.001, P < 0.001 and P=0.0002, respectively). Airway neutrophil density in bronchiectasis but not in controls, correlated with TNFalpha-positive cell density (r=0.71, P=0.004). A significant correlation between airway macrophage and TNFalpha-positive cell densities was demonstrated in both control and bronchiectatic airways (r=0.63, P=0.016 and r=0.60, P=0.02 respectively). Neutrophil density negatively correlated with per cent forced vital capacity (FVC%) predicted among patients with bronchiectasis (r=-0.53, P=0.04). Bronchiectasis patients who were regular sputum producers had a significantly higher macrophage, but not neutrophil density than their counterparts (P=0.02 and P=0.48 respectively). Our original findings suggest that airway macrophages could contribute to neutrophil influx into airway walls through their production of TNFalpha and therefore play an important role in the pathogenesis of bronchiectasis.

Aged↗
PubMed2001

Adenocarcinoma of the lung in Chinese patients: a revisit and some perspectives from the literature.

AIM: To establish an updated clinical profile of adenocarcinoma of the lung. DESIGN: Retrospective review of clinical charts, chest radiography, and computed tomography of consecutive patients who attended Queen Mary Hospital in Hong Kong between June 1995 and December 1997. RESULTS: In the 115 patients studied, 13% were <40 years of age (33.3% ever smokers). Haemoptysis is more common among patients with early disease, while finger clubbing was detected more commonly among smokers and ex-smokers. Most (98.3%) patients had abnormal chest radiology including presence of mass lesion, pleural effusion, collapse/consolidation, and effusion. Patients with adenocarcinoma were significantly more likely to be younger, female, in advanced disease (stage IIIB and IV), non-smoker, and symptomatic on presentation (p<0.05) than those with squamous cell lung cancer (n=128). CONCLUSION: The clinical profile of Chinese adenocarcinoma patients should help clinicians in the diagnosis and management of these patients.

Adenocarcinoma↗
PubMed2001

Radiologic manifestations of granulocytic sarcoma in adult leukemia.

OBJECTIVE: This study was conducted to summarize the clinical and radiologic presentations including pertinent imaging features of granulocytic sarcoma, a rare extramedullary tumor of acute myeloid leukemia, in 11 adult patients. CONCLUSION: In patients in our study, the clinical and radiologic manifestations of granulocytic sarcoma were variable and occurred most commonly as disease progression in acute myeloid leukemia (73% of the patients). Granulocytic sarcoma lesions were multiple soft-tissue masses with variable enhancement, recurring in nearly 50% of patients at different sites and points of time during the course of the disease. Lesions in the central nervous system, subcutaneous tissues, and genitourinary system accounted for nearly 52% of all lesions. In general, granulocytic sarcoma masses were isodense to muscle on CT scans, and isointense and hyperintense (mild to moderate) on T1- and T2-weighted MR images, respectively. The presence of peripheral rim enhancement with hypodense or hypointense centers on T1-weighted images may, however, mimic an abscess.

Acute Disease↗
PubMed2001

Primary hepatic lymphoma.

We report the histologic and CT imaging findings of a patient with primary Burkitt's lymphoma of the liver. She presented with a massive, painless abdominal mass. The tumor responded to chemotherapy but the patient died of neutropenic sepsis.

Aged↗
PubMed2001

Absence of gallium uptake in multicentric Castleman's disease of plasma cell type.

Multicentric Castleman's disease (MCD) of plasma cell type is a reactive lymphoproliferative disease. While 67Ga scanning is useful in the detection of malignant lymphomas, its role in reactive lymphadenopathy is unknown. We report the absence of 67Ga uptake in three patients with MCD of plasma cell type and present a review of the English literature on this condition.

Castleman Disease↗