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Jessica W T Leung

Publications and source records attributed to Jessica W T Leung.

14 recordsLinked to original sources
PubMed2007

Performance parameters for screening and diagnostic mammography in a community practice: are there differences between specialists and general radiologists?

OBJECTIVE: The purpose of this study was to compare the performance of general radiologists in interpretation of mammograms with that of breast imaging specialists in a high-volume community hospital-based private practice. MATERIALS AND METHODS: A retrospective observational study was conducted with data prospectively collected over a 5-year period in a community hospital-based practice in which 106,405 screening and 52,149 diagnostic mammograms were performed. The performance of three radiologists specializing in breast imaging was compared with that of six general radiologists. The following data were extracted and analyzed: recall rate, biopsy recommendation rate, and cancer detection rate. Statistical analysis was performed with a chi-square test and two-tailed calculation of p values. RESULTS: The recall rates of the specialists and generalists were nearly the same at 6.5% and 6.7%, respectively. The biopsy recommendation rate at recall from screening examinations was nearly the same for generalists and specialists (1.2% and 1.1%, respectively; p = 0.4504). This rate also was similar for diagnostic examinations (8.5% for generalists; 8.4% for specialists; p = 0.4086). The cancer detection rate in the screening setting was slightly higher for specialists than for generalists: 2.5 and 2.0 cancers per 1,000 cases, respectively (p = 0.0614). The cancer detection rate in the diagnostic setting was 24.2% higher among specialists (20.0 cancers per 1,000 cases) compared with generalists (16.1 cancers per 1,000 cases) (p = 0.0177). CONCLUSION: The only statistically significant difference between generalists and specialists was in cancer detection rate among patients undergoing diagnostic mammography. No statistically significant difference was identified between the two groups in terms of recall rate, biopsy recommendation rate, or percentage of favorable-prognosis cases of cancer detected. There was a trend toward greater cancer detection by specialists in the screening setting.

Breast Neoplasms↗
PubMed2006

Lymphoepithelioma-like carcinoma of the lung: radiologic features of an uncommon primary pulmonary neoplasm.

OBJECTIVE: The purpose of this study was to review the chest radiographic, CT, and MRI appearances of primary pulmonary lymphoepithelioma-like carcinoma (LELC). CONCLUSION: Primary pulmonary LELC is histopathologically identical to nasopharyngeal carcinoma. The radiographic, CT, and MRI features of primary pulmonary LELC are nonspecific, often resembling those of bronchogenic carcinoma. Primary pulmonary LELC usually presents as a poorly circumscribed, enhancing, peripheral solitary pulmonary nodule on CT; necrosis may be present and is considered a poor prognostic sign. MRI shows isointense to low-intensity signal on T1-weighted images and mildly increased signal on T2-weighted images; enhancement of abnormal tissue is typical. Most patients present with early-stage disease. Primary pulmonary LELC should be suspected in selected patients and requires differentiation from bronchogenic carcinoma and metastatic nasopharyngeal carcinoma.

Carcinoma↗
PubMed2005

Differences in screening mammography outcomes among White, Chinese, and Filipino women.

BACKGROUND: The accuracy of screening mammography among Asian women in the United States has received little attention. We determined whether the accuracy of screening mammography for Chinese and Filipino women differs from that of white women. METHODS: We examined a cohort of white, Chinese, and Filipino women 40 years and older who underwent 200,402, 72,604, and 19,087 screening examinations, respectively, between January 1986 and December 2001 in San Francisco County, California, of whom 2177 were diagnosed with breast cancer within 12 months of a screening examination. By linking screening examinations to the regional Surveillance, Epidemiology and End Results program and the California Cancer Registry, we identified the occurrence of any invasive cancer or ductal carcinoma in situ and then calculated the rate of cancer per 1000 screenings and the sensitivity of mammography. RESULTS: The rate of invasive breast cancer per 1000 screenings was 45% lower for Chinese than for white women aged 50 to 69 years (3.8 vs 6.9; P<.001) and 29% lower for Filipino than for white women (4.9 vs 6.9; P = .03). Rates of ductal carcinoma in situ were similar across all ethnic groups (1.6-1.7 per 1000 screenings; P>or=.60). The sensitivity of mammography was similar for white, Chinese, and Filipino women (81.6%-84.3%; P>.30). CONCLUSIONS: Screening mammography has similar accuracy among white, Chinese, and Filipino women, although the absolute benefit of screening, in terms of breast cancer deaths averted, is likely to be less among Asian women because the rates of invasive cancer are lower compared with white women of similar age. Overdiagnosis of ductal carcinoma in situ with screening mammography among Asian women is likely to be comparable to that of white women because the rate of ductal carcinoma in situ was similar in all the examined ethnic groups.

Adult↗
PubMed2005

High-resolution CT of the lung: patterns of disease and differential diagnoses.

High-resolution CT (HRCT) of the lung is a powerful tool for the investigation of patients with acute or chronic respiratory symptoms or diffuse parenchymal lung disease. Detailed knowledge of normal pulmonary anatomy and an understanding of how normal anatomy is altered in disease states are required to appreciate fully HRCT findings in patients with pulmonary disease. Detailed knowledge of the technical aspects of HRCT examinations is required for optimal image quality. With the proper foundation, a pattern approach to HRCT interpretation may then be used successfully to provide accurate and reproducible interpretation.

Diagnosis, Differential↗
PubMed2005

Performance benchmarks for diagnostic mammography.

PURPOSE: To evaluate a range of performance parameters pertinent to the comprehensive auditing of diagnostic mammography examinations, and to derive performance benchmarks therefrom, by pooling data collected from large numbers of patients and radiologists that are likely to be representative of mammography practice in the United States. MATERIALS AND METHODS: Institutional review board approval was met, informed consent was not required, and this study was Health Insurance Portability and Accountability Act compliant. Six mammography registries contributed data to the Breast Cancer Surveillance Consortium (BCSC), providing patient demographic and clinical information, mammogram interpretation data, and biopsy results from defined population-based catchment areas. The study involved 151 mammography facilities and 646 interpreting radiologists. The study population included women 18 years of age or older who underwent at least one diagnostic mammography examination between 1996 and 2001. Collected data were used to derive mean performance parameter values, including abnormal interpretation rate, positive predictive value (for abnormal interpretation, biopsy recommended, and biopsy performed), cancer diagnosis rate, invasive cancer size, and the percentages of minimal cancers, axillary node-negative invasive cancers, and stage 0 and I cancers. Additional benchmarks were derived for these performance parameters, including 10th, 25th, 50th (median), 75th, and 90th percentile values. RESULTS: The study involved 332,926 diagnostic mammography examinations. Mean performance parameter values were abnormal interpretation rate, 8.0%; positive predictive value for abnormal interpretation, 31.4%; positive predictive value for biopsy recommended, 31.5%; positive predictive value for biopsy performed, 39.5%; cancer diagnosis rate, 25.3 per 1000 examinations; invasive cancer size, 20.2 mm; percentage of minimal cancers, 42.0%; percentage of axillary node-negative invasive cancers, 73.6%; and percentage of stage 0 and I cancers, 62.4%. CONCLUSION: The presented BCSC outcomes data and performance benchmarks may be used by mammography facilities and individual radiologists to evaluate their own performance for diagnostic mammography as determined by means of periodic comprehensive audits.

Adult↗
PubMed2005

Screening mammography reduces morbidity of breast cancer treatment.

OBJECTIVE: This commentary discusses the retrospective cohort study by Barth et al. studying the effect of screening mammography on morbidity of breast cancer treatment. CONCLUSION: Barth et al. found that cancers identified at screening mammography (versus those detected by physical examination) were smaller and more frequently node-negative. Hence, the former group of breast cancer patients was more likely to be treated with less morbid therapy. This evidence-based study contributes to the clinical practice of screening mammography.

Adult↗
PubMed2005

Imaging findings in Takayasu's arteritis.

OBJECTIVE: The objective of our study was to evaluate the clinical usefulness of cross-sectional imaging for establishing the diagnosis of Takayasu's arteritis (TA), an inflammatory vascular disorder that produces arterial stenoses and aneurysms primarily involving the thoracoabdominal aorta and its branches and the pulmonary arteries. CONCLUSION: CT and MRI findings of TA include vascular wall thickening and enhancement early in the disease, and arterial stenoses, occlusions, and aneurysms later in the disease. Cross-sectional imaging is useful for establishing the diagnosis of TA and for showing response to nonsurgical therapy or for planning a surgical intervention.

Adult↗
PubMed2002

New modalities in breast imaging: digital mammography, positron emission tomography, and sestamibi scintimammography.

Digital mammography, PET, and sestamibi scintimammography are three new modalities in breast imaging. DM has advantages over film-screen mammography in image storage, retrieval, and processing and may lower the recall rate. Computer-aided detection may increase the sensitivity of mammographic screening without a substantial reduction in specificity. Whereas PET and sestambi scintimammography are not useful in breast cancer screening, PET may play a role in detecting nodal metastases and monitoring treatment response, and sestamibi scintimammography in selected cases may serve as an adjunct to conventional imaging. The cost-effectiveness of these new modalities remains to be evaluated, but all have the potential to significantly advance the diagnosis and management of women with breast cancer.

Breast Neoplasms↗
PubMed2002

Thoracic complications of illicit drug use: an organ system approach.

Illicit drug use constitutes a major health problem and may be associated with various thoracic complications. These complications vary depending on the specific drug used and the route of administration. Commonly abused drugs that may play a role in causing thoracic disease include cocaine, opiates, and methamphetamine derivatives. Intravenously abused oral medications may contain filler agents that may be responsible for disease. Thoracic complications may be categorized as pulmonary, pleural, mediastinal, cardiovascular, and chest wall complications. Pulmonary complications of drug abuse include pneumonia, cardiogenic edema, acute lung injury, pulmonary hemorrhage, and aspiration pneumonia. Filler agents such as talc may result in panacinar emphysema or high-attenuation upper-lobe conglomerate masses. The primary pleural complication of illicit drug use is pneumothorax. Mediastinal and cardiovascular complications of illicit drug use include pneumomediastinum, cardiomyopathy, myocardial infarction, aortic dissection, and injection-related pseudoaneurysms. Chest wall complications include diskitis and vertebral osteomyelitis, epidural abscess, necrotizing fasciitis, costochondritis, and septic arthritis. Categorization of thoracic complications of illicit drug use may facilitate understanding of these disorders and allow accurate diagnosis.

Aortic Dissection↗
PubMed2002

Utility of targeted sonography in the evaluation of focal breast pain.

OBJECTIVE: To determine the utility of targeted sonography in the evaluation of patients with focal breast pain. METHODS: From January 1995 through December 1999, 110 targeted sonographic examinations were performed in 99 patients for evaluation of focal breast pain in the absence of an associated palpable mass. The sonographic, mammographic, and clinical findings were reviewed. The hospital pathology database was searched to identify any interval cancers and false-negative interpretations. RESULTS: No cancer was identified in any of the 110 examinations. Eighty-five (77.3%) of the examinations had negative findings. Cysts were identified in 15 cases (13.6%), and 3 solid masses (2.7%) were identified. Two of these 3 solid masses had biopsies and were shown to be benign, whereas the third mass was followed for 29 months without change. Most patients were premenopausal, had no family or personal history of breast cancer, and were not taking exogenous hormones. Eighty-five patients (77%) were referred by primary care physicians. CONCLUSIONS: In patients with focal breast pain without an associated palpable mass, sonography may be more useful for patient reassurance than for cancer detection.

Adult↗