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D B Chang

Publications and source records attributed to D B Chang.

At least 19 recordsLinked to original sources
PubMed1998

Tumour-infiltrating lymphocytes in non-small cell lung cancer are activated T lymphocytes.

This study was carried out in order to investigate the local immune reaction of tumour-infiltrating lymphocytes (TILs) in the primary tumours of non-small cell lung carcinomas. Thirty non-small cell lung cancer (NSCLC) patients were included. The tumour tissue was taken at thoracotomy and monocellular suspension of the tumour was obtained by mechanical disaggregation. Dual-coloured flow cytometric analysis of TILs and their corresponding peripheral blood lymphocytes (PBLs) was performed. Tumour-infiltrating lymphocytes contained significantly higher proportions of CD3(+) T lymphocytes and CD8(+) T lymphocytes than the corresponding PBLs (82.0%+/-13.9% vs 66.3%+/-10.6% for CD3, P<0.001; 39.0%+/-18.4% vs 26.4%+/-5.2% for CD8, P<0.001). Tumour-infiltrating lymphocytes contained significantly higher proportions of activated memory lymphocytes than PBLs did (9.8%+/-8.6% vs 1.3%+/-1.5% for CD25, P<0.001; 40.5%+/-30.2% vs 10.2%+/-14.8% for CD71, P<0.001; 75.5%+/-11.9% vs 28.6%+/-9.8% for HLA-DR, P<0.001). These findings were also found in both CD4(+) TILs and CD8(+) TILs. The TILs of NSCLC contained higher proportions of T lymphocytes and CD8(+) lymphocytes than their corresponding peripheral bloods. The proportions of activated memory lymphocytes were also significantly higher in the TILs, both in CD4(+) TILs and CD8(+) TILs, than the corresponding PBLs.

Adult↗
PubMed1996

Nucleolar organizer regions as a prognostic factor in surgically treated lung cancer patients.

The prognostic value of the number of nucleolar organizer regions (NORs) (DNA loops in the nucleus) in tumor cells from various kinds of malignancies has been widely studied in recent years. During the period 1989 to 1992, a total of 73 primary lung tumors was examined for the number of NORs by silver staining AgNOR proteins on the stump smear of resected specimens in this hospital. The relations of the mean number of AgNOR per cell with other factors such as sex, age, habit of smoking, performance status, tumor location, tumor size, pathological stage, histological type, degree of differentiation, and whether histologically vascular or lymphatic invasion were analysed. It was found that the mean number of AgNOR was significantly different between positives and negatives of histologically vascular or lymphatic invasion (6.4 +/- 0.4 vs 5.5 +/- 0.2) (p < 0.05). Both single and multiple-variate analysis of patient survival revealed that the mean number of AgNOR was a significant prognostic factor, as were pathological stage, histological type, and performance status of the patient. Patients with a higher mean number of AgNOR (> 7) had a significantly worse prognosis compared with those with less AgNOR (< or = 7) (median survival 28 versus 43 months) (p < 0.05). It was concluded that the mean number of AgNOR of tumor cells is a significant prognostic factor in surgically treated lung cancer patients.

Adult↗
PubMed1995

Clinical spectrum of tuberculosis in older patients.

OBJECTIVE: To investigate the clinical differences between old and young patients infected with Mycobacterium tuberculosis in a developing country. DESIGN: Retrospective chart and chest radiograph review. SETTING: A university-affiliated teaching hospital. PATIENTS: The medical records of patients with documented tuberculosis (TB) from January 1990 through December 1991 were analyzed. Clinical assessment included sex, age, diagnosis at first visit, past history, symptoms and signs, laboratory data, X-ray findings, bacteriological examinations, outcome, time elapsed from first visit to initiation of anti-TB therapy and the major determinants for starting anti-TB therapy. Statistical significances were analyzed by Student's t test and chi 2 tests. RESULTS: Among 205 patients with culture-proven TB, 57 were 65 years of age and older (range, 65 to 91; mean, 73) and 148 under 65 years of age (range, 16 to 64; mean, 41). There was a higher incidence of previous TB (26.3% vs. 16.2%) and diabetes mellitus (24.5% vs. 14.3%) in the elderly patients. Initial diagnosis of TB at first visit was less frequent in the elderly than in the young group (38.6% vs. 47.3%), although symptoms and signs at first visit were similar in each of the age groups. Radiographic presentation with mass lesions was more frequently encountered in elderly patients (10.5% vs. 2.1%, P < .05). Elapsed time from the first visit to suspicion of TB and the initiation of anti-TB therapy was frequently delayed in elderly patients (22 +/- 23 vs. 13 +/- 20 days, P < .05). The incidence of drug-resistance (39% vs. 16%, P < .05) and unfavorable response to anti-TB therapy (17.5% vs. 3.4%, P < .05) were significantly higher in the older patients. CONCLUSIONS: Although clinical presentation of TB in the elderly did not differ significantly from that in younger patients, this study showed that diagnosis and treatment were more often delayed in the elderly, and there was a higher incidence of treatment failure.

Adolescent↗
PubMed1995

Direct determination of cryptococcal antigen in transthoracic needle aspirate for diagnosis of pulmonary cryptococcosis.

Pulmonary cryptococcosis causes significant morbidity and mortality in immunocompromised patients. Definitive diagnosis of pulmonary cryptococcosis is usually difficult. The use of direct determination of cryptococcal antigen in transthoracic needle aspirate to diagnose pulmonary cryptococcosis was investigated. Over a 2-year period, we studied a total of 41 patients with respiratory symptoms and pulmonary infiltrates of unknown etiology who were suspected of having pulmonary cryptococcosis. Twenty-two patients were immunocompetent patients and 19 patients were immunocompromised. A diagnosis of pulmonary cryptococcosis was based on cytological examination, culture for Cryptococcus neoformans, histopathologic examination, and clinical response to antifungal therapy. All patients underwent chest ultrasound and ultrasound-guided percutaneous transthoracic needle aspiration to obtain specimens for cryptococcal antigen determination. The presence of cryptococcal antigen was determined by the latex agglutination system (CALAS; Meridian Diagnostics, Cincinnati, Ohio). An antigen titer equal to or greater than 1:8 was considered positive. The specimens were also sent for cytological examination, fungal culture, and/or histopathologic examination. A final diagnosis of pulmonary cryptococcosis was made in eight patients. Direct determinations of cryptococcal antigen in lung aspirate were positive in all eight patients with pulmonary cryptococcosis (100% sensitivity, 97% specificity, a positive predictive value of 89%, and negative value of 100%), and there was only one false-positive in noncryptococcosis patients. The diagnostic accuracy was 97.5%. Serum cryptococcal antigen was positive in only three patients with pulmonary cryptococcosis (sensitivity, 37.5%). This study showed that direct measurement of cryptococcal antigen in lung aspirate can be a rapid and useful test for diagnosis of pulmonary cryptococcosis.

Adolescent↗
PubMed1995

Transthoracic needle biopsy of thoracic tumours by a colour Doppler ultrasound puncture guiding device.

BACKGROUND: Ultrasound guided transthoracic needle aspiration biopsy has recently been used to obtain specimens for histological diagnosis of pulmonary and mediastinal tumours. Conventional real time, grey scale puncture guiding devices cannot differentiate vascular structures, and clear visualisation of the needle shaft or tip within a desired target is not always possible. This study describes a new built-in colour Doppler ultrasound puncture guiding device and assesses the relative safety of transthoracic needle aspiration biopsy of thoracic tumours by grey scale or colour Doppler ultrasound guidance. METHODS: Thirty patients with radiographic evidence of pulmonary (22 patients) or mediastinal tumours (eight patients) underwent ultrasonographic evaluation and transthoracic needle aspiration biopsy by using the colour Doppler ultrasound puncture guiding device (Aloka UST 5045P-3.5). These tumours were initially examined by grey scale ultrasound, and colour Doppler imaging was then used to evaluate the number of blood vessels surrounding and within the target tumour and the possibility of visualisation of the needle shaft or needle tip during the aspiration biopsy procedure. RESULTS: The colour Doppler ultrasound guiding device was far superior to the grey scale device for identification of the number of vessels surrounding or within the target tumour (83% v 20%) and for visualisation of the needle shaft or needle tip (80% v 17%). CONCLUSIONS: By using the colour Doppler ultrasound puncture device, vascular structures surrounding or within the target tumour can be verified. Visualisation of the needle shaft or tip is also better. Biopsy routes can be selected to avoid puncturing vessels. This approach should be particularly helpful for guiding biopsies of mediastinal tumours, where puncturing the heart or great vessels is a potential complication.

Adult↗
PubMed1995

Midbrain hemorrhage presenting as bilateral ptosis without hemiplegia: a case report.

A 66-year-old man suddenly developed bilateral ptosis after awaking from a nap. He did not experience nausea, vomiting or headache. In the emergency room, high blood pressure was noted. On examination, his consciousness was clear. Ptosis was present bilaterally and worse on the right side. The pupils promptly constricted to light. He could fully adduct his eyes during conjugate gaze movements, but convergence was impaired in the right eye. There was no diplopia or nystagmus. The assessment of the motor and sensory systems revealed no significant findings. Computed tomographic scanning and magnetic resonance imaging of the brain showed a small hematoma in the midbrain. Six months later, ptosis improved; however, the convergence deficit remained.

Blepharoptosis↗
PubMed1995

Systemic lupus erythematosus presenting as pleural effusion: report of a case.

Systemic lupus erythematosus (SLE) presenting as a pleural effusion in a young male is not common. This paper describes a 20-year-old man who was admitted to hospital with a spiking fever, chills and cough. A chest x-ray showed alveolar infiltration and a moderate right-sided pleural effusion. The patient was treated for parapneumonic effusion. Thoracentesis was performed and cytology of the aspirated fluid was initially interpreted as showing only numerous polymorphonuclear (PMN) leukocytes. However, in spite of antibiotic treatment the symptoms persisted. A careful review of the cytology specimen showed classic lupus erythematosus (LE) cells in addition to PMN cells. Subsequent investigation, including antinuclear antibodies titer, confirmed the diagnosis of LE pleurisy. Therapy with antibiotics was discontinued and treatment with prednisolone 20 mg daily was begun. There was a rapid clinical response including resolution of the fever and pleural effusion.

Adult↗
PubMed1994

Carcinoid tumours of the thymus.

BACKGROUND: Carcinoid tumours of the thymus are rare. The clinical manifestations, radiographic findings, and cytological features of eight histopathologically verified thymic carcinoid tumours have been assessed. METHODS: One hundred and sixty two patients of mean age 52 (range 31-68) years with malignant mediastinal tumours were reviewed retrospectively and eight cases of thymic carcinoid were identified. Four of the eight patients were diagnosed by percutaneous ultrasound guided fine needle aspiration biopsy via a parasternal approach. RESULTS: Two patients had Cushing's syndrome at presentation and four had symptoms and signs secondary to mediastinal compression. Two were asymptomatic. Local extension of the tumour to pleura, pericardium, great vessels, phrenic nerve or regional lymph nodes, or both, were found in seven patients. Only one had the tumour confined to the thymus at diagnosis. Distant metastases were found in two patients, one to both lungs and the other in the iliac bone. Local recurrence or distant metastases developed 15-60 months after surgery in four of the five patients who underwent radical resection of the thymic tumour. Three patients died at 17 months, 34 months, and 10 years after diagnosis. The other five patients are alive at 9-51 months. CONCLUSION: Thymic carcinoid is a slow growing tumour with a poor prognosis because of its tendency to local and distant spread. Cytological examination of samples obtained by ultrasound guided fine needle aspiration may provide a useful method for diagnosis in selected patients.

Adult↗
PubMed1994

Ultrasound guided pericardial drainage and intrapericardial instillation of mitomycin C for malignant pericardial effusion.

BACKGROUND: Conservative treatment of malignant pericardial effusion by intrapericardial instillation of a sclerosing agent may be an alternative to surgery. METHODS: Twenty patients with malignant pericardial effusion were treated by ultrasound guided pericardiocentesis and the intrapericardial instillation of mitomycin C. RESULTS: Mitomycin C was effective in controlling the pericardial effusion in 70% of patients without causing side effects, except for pericardial constriction seven months later in one subject. CONCLUSIONS: Ultrasound guided intrapericardial instillation of mitomycin C is a suitable alternative in the management of malignant pericardial effusion.

Adult↗
PubMed1994

Superior vena cava syndrome. Rapid histologic diagnosis by ultrasound-guided transthoracic needle aspiration biopsy.

We prospectively analyzed the diagnostic yield and safety of ultrasound (US)-guided transthoracic needle aspiration biopsy in the histologic diagnosis of 40 patients with superior vena cava (SVC) syndrome. During a 4-yr period, 40 patients with SVC obstruction were admitted to National Taiwan University Hospital. Of these patients 10 had histologic confirmation by sputum cytology (3 patients), fiberoptic bronchoscopy with biopsy (2 patients), or lymph node biopsy (5 patients) at admission. A total of 30 undiagnosed patients underwent real-time ultrasonographic (US) evaluation as well as color Doppler imaging. Patients with tumor detectable by US underwent US-guided transthoracic needle aspiration biopsy. Of the 30 patients who received US chest examination, 29 had widening of the upper mediastinal shadows in the chest radiographs. In 27 patients tumors were detected by chest US. After assessment of collateral vessels by color Doppler US, these 27 patients underwent US-guided transthoracic needle aspiration biopsies; histologic diagnoses were confirmed in 25. The diagnostic yield was 83.3%. The mean duration from admission to histologic diagnosis was 2.1 days. None of the patients developed complications. We conclude that chest US and color Doppler images are useful tools for evaluation of patients with SVC syndrome. US-guided transthoracic needle aspiration biopsy appears to be a safe, effective, and rapid approach for obtaining an accurate histologic diagnosis. Specific treatment can thus be initiated without delay.

Adult↗
PubMed1994

The bacteriology of obstructive pneumonitis. A prospective study using ultrasound-guided transthoracic needle aspiration.

Obstructive pneumonitis, the opacity that develops distal to an obstructing endobronchial lesion or external compression, is actually a combination of atelectasis, bronchiectasis with mucus plugging, and true parenchymal inflammation. In the majority of cases, it is usually not possible to determine whether infection is present or not from the radiographic findings alone. The aim of this study was to evaluate the bacteriology of obstructive pneumonitis and the influence of this result on the treatment of patients. From March 1992 to February 1993, 26 consecutive patients (20 men and six women) with obstructive pneumonitis were investigated. The obstructive pneumonitis had been caused by malignant tumors in 24 and benign lesions in two. Chest ultrasound (US) and US-guided percutaneous transthoracic aspirations were undergone to obtain specimens for microbiologic examination. Microorganisms were isolated from seven of nine febrile patients and two of 17 nonfebrile patients. A total of 16 bacterial strains are detected in obstructive pneumonitis (Pseudomonas aeruginosa, Klebsiella pneumoniae, viridant streptococci, Bacteroides fragilis, two Peptostreptococcus species, Mycobacterium tuberculosis, Pseudomonas maltophilia, Streptococcus sanguis, Staphylococcus aureus, Bacteroides thetaiotamomicrons, Bacteroides intermedius, Bacteroides species, Veillonella species, aerobic gram-positive bacilli, and Escherichia coli). In five cases the isolates were monobacteriae, and in the remaining four cases, cultures yielded more than one bacteria. The results of aspirate cultures led to changes in the initial antibiotic trial in seven of nine patients, and fever subsided thereafter. Pneumothorax occurred in one cases as the sole complication. The pathogen causing obstructive pneumonitis is very heterogeneous, and polymicrobial infection is common.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Image comparison of real-time gray-scale ultrasound and color Doppler ultrasound for use in diagnosis of minimal pleural effusion.

To assess the value of color Doppler ultrasound in distinguishing minimal pleural effusion from pleural thickening, a prospective analysis was done on the ultrasonographic findings in 51 patients. Real-time, gray-scale, and color Doppler chest ultrasound examinations were carried out by different sonographers who had no clinical information concerning the patients. The sonographer evaluated the images for internal echogenicity of the effusion, pleural lesions that change shape with respiration, and movable septa and echo-densities in pleural space in conventional gray-scale as well as color signal in color Doppler ultrasound. Of the 35 patients with true effusion, 33 had positive color signal (sensitivity 94.3%, 95% confidence intervals [CI] 89 to 98.6%); in 16 patients without effusion, none had color signal (specificity 100%, 95% CI 83 to 100%). Although real-time, gray-scale ultrasound is also sensitive for detecting minimal effusion (sensitivity 100%, 95% CI 92 to 100%), it is less specific (specificity 68.7%, 95% CI 46 to 91.5%). Five of 16 examinations showing fluid-like lesions were found to be deceptive. With relatively high sensitivity and specificity, this method proved to be a useful diagnostic aid to real-time, gray-scale ultrasound for diagnosis of minimal or loculated effusion.

Adolescent↗
PubMed1994

Differentiation of benign and malignant cervical lymph nodes with color Doppler sonography.

OBJECTIVE: This study proposed to evaluate the efficacy of color Doppler sonography in detecting possible differences in blood flow patterns between malignant and benign cervical lymph nodes. SUBJECTS AND METHODS: During a period of 12 months, the palpable cervical lymph nodes of 48 untreated patients were prospectively evaluated with color Doppler sonography and Doppler flow wave analysis. Histopathologic diagnoses were obtained by sonographically guided fine-needle aspiration biopsy and/or excisional biopsy. RESULTS: We found 16 benign lymph nodes (four were tuberculous lymphadenitis, four were reactive hyperplasia, and eight were unspecified) and 32 malignant lymph nodes (13 were squamous cell carcinomas, nine were adenocarcinomas, four were small-cell carcinomas, three were lymphomas, and three were miscellaneous). Color Doppler flow patterns were seen in six (38%) of the 16 benign lymph nodes and in 29 (91%) of the 32 malignant lymph nodes. Twenty-six (81%) of the 32 malignant lymph nodes had abnormal flow patterns, with resistance indexes less than 0.6. However, three (19%) of the 16 benign lymph nodes also had abnormal flow patterns, and only seven (54%) of 13 squamous cell carcinomas had abnormal flow patterns. CONCLUSION: Color Doppler sonography has limited clinical value in differentiating malignant from benign cervical lymph nodes and in obviating biopsy.

Adenocarcinoma↗
PubMed1994

Color Doppler sonography of benign and malignant pulmonary masses.

OBJECTIVE: The purpose of this study was to compare blood flow in benign and malignant pulmonary masses by assessing the spectral waveforms obtained during color Doppler sonography. SUBJECTS AND METHODS: Fifty lung cancers in 46 patients and 28 benign lung lesions in 28 patients were evaluated with color Doppler sonography. Spectral wave analysis of blood flow (specifically, the Doppler variables of pulsatility index, resistive index, peak systolic velocity, and end diastolic velocity) was used to determine the distal impedance of vessels in malignant and benign pulmonary lesions. RESULTS: The flow signal detection rates for lung cancers and benign pulmonary lesions were 64% and 79%, respectively. All lung cancers with detectable flow signals had either relatively low-impedance flows or arteriovenous shunting, unlike the benign lesions, which usually had relatively high-impedance flows. For lung cancers, the pulsatility index was 1.43 +/- 0.31, the resistive index was 0.52 +/- 0.13, peak systolic velocity was 0.17 +/- 0.07 m/sec, and end diastolic velocity was 0.07 +/- 0.03 m/sec. For benign lung lesions, the pulsatility index was 3.32 +/- 0.68, the resistive index was 0.90 +/- 0.06, peak systolic velocity was 0.28 +/- 0.09 m/sec, and end diastolic velocity was 0.03 +/- 0.01 m/sec. All four variables were significantly different (p < .001) between lung cancers and benign lung lesions. When a cutoff value of mean +/- 2 SD was used, the resistive index and pulsatility index were shown to be sensitive and specific for the diagnosis of lung cancer (sensitivity, specificity = 100%, 95% for resistive index; 97%, 95% for pulsatility index). Flow was detected less often in squamous cell carcinoma than in adenocarcinoma and small-cell carcinoma. CONCLUSION: We conclude that color Doppler sonography is useful for showing vascularity in pulmonary masses, and may be helpful in differentiating malignant from benign lung tumors.

Blood Flow Velocity↗
PubMed1993

Diagnosis of pulmonary cryptococcosis by ultrasound guided percutaneous aspiration.

BACKGROUND: Ultrasound is useful for locating thoracic lesions and guiding biopsy procedures. The use of sonographic appearances and ultrasound guided needle aspiration has led to the diagnosis of pulmonary cryptococcosis at this hospital. METHODS: Six hundred and eight patients who had ultrasound guided lung aspirations were reviewed retrospectively and nine with documented pulmonary cryptococcosis were collected. All patients had nodules or infiltrates on the chest radiograph. The needle aspirates obtained under ultrasound guidance were stained by Riu's or Papanicolaou's method or with India ink, and six were sent for culture. Five patients also underwent bronchoscopy and biopsy. RESULTS: The nine patients had 18 pulmonary lesions, of which 15 were nodules and three infiltrates. Fifteen lesions were detectable by ultrasound, which showed the nodules to be hypoechoic with eccentrically located air echoes. In eight of the nine cases cryptococci were detected after the lung aspirates had been stained with Riu's or Papanicolaou stain or with India ink. In five of the six aspirates sent for fungal culture Cryptococcus neoformans was isolated. The diagnostic yield was higher than that of bronchoscopy. None developed post-aspiration pneumothorax or any evidence of late dissemination. CONCLUSIONS: Because they tend to be subpleural pulmonary cryptococcal lesions seem to be identifiable by ultrasound. Ultrasound guided lung aspiration is an effective, rapid, and safe method for diagnosis.

Adult↗
PubMed1993

Ultrasound guided aspiration biopsy for pulmonary tuberculosis with unusual radiographic appearances.

BACKGROUND: Pulmonary tuberculosis can produce unusual radiographic appearances and negative results of sputum and bronchoscopic examinations are common. This study assessed the value of ultrasound guided aspiration biopsy in the diagnosis of pulmonary tuberculosis with unusual radiographic appearances. METHODS: Thirteen patients, ultimately diagnosed as having tuberculosis, underwent a chest ultrasonographic examination between June 1984 and August 1991. All had sputum available for examination and nine were also examined by bronchoscopy. Ten patients who had a negative sputum smear and negative bronchoscopic brushing smears underwent ultrasound guided aspiration or biopsy. Percutaneous aspiration was performed with a 22 gauge needle. If the smear did not reveal acid fast bacilli, a biopsy sample was taken with a 16 gauge Tru-cut needle to obtain a histological diagnosis. RESULTS: The ultrasonographic examination delineated the more complex nature of the lesions better than the chest radiograph. Ultrasound guided aspiration biopsy provided the diagnosis in nine of 10 patients, while the sputum smear and culture provided diagnosis in five of 13, and bronchoscopy in four of nine. In terms of rapid diagnosis, ultrasound guided aspiration biopsy gave the diagnosis in eight of 10 cases. No patient developed a major complication. CONCLUSION: Ultrasonography can direct the needle to the most suitable part of a lesion to obtain the relevant specimens. The diagnostic yield is high and the procedure is relatively safe. It is especially helpful in patients with negative results of sputum and bronchoscopic examinations.

Adolescent↗
PubMed1993

Ultrasound study in unilateral hemithorax opacification. Image comparison with computed tomography.

The diagnostic capability of chest ultrasonography was assessed for use in evaluation of patients presenting with opacification of unilateral hemithorax on chest radiography. Hemithorax opacification provided an "ultrasonic window" for ultrasonic wave penetration to detect any underlying diseases. Fifty patients were included over a study period of 24 months. All had received both chest ultrasonography (US) and computed tomography (CT) examinations, and their underlying diseases had been confirmed by various methods. Comparisons between the findings of chest US and of CT were made in three compartments: pleura, parenchyma, and mediastinum. Diagnostic sensitivity and specificity of chest US was defined by using CT as the "gold standard." The ability of US to detect underlying diseases was comparable to that of CT in pleural and parenchymal lesions. But US was inferior to CT for demonstration of mediastinal lesions. The diagnostic sensitivity of US was 95.1% in pleural lesions, 82.8% in parenchymal lesions, and only 30% in mediastinal lesions. US missed 14 lesions demonstrated by CT (seven mediastinal lesions, five parenchymal tumors, and two pleural nodules), but it showed six lesions that CT had failed to detect (four focal pleural thickening and two parenchymal tumors). US-related procedures were performed (thoracentesis in 33 patients, pleural biopsy in 10 patients, and US-guided aspiration/cutting biopsy in 11 patients) with a high diagnostic yield and no complications. The conclusion was that chest ultrasonography is useful, particularly as a first-step examination for patients with total or nearly total opacification of the hemithorax.

Adolescent↗