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Yih-Leong Chang

Publications and source records attributed to Yih-Leong Chang.

At least 19 recordsLinked to original sources

Clonality and prognostic implications of p53 and epidermal growth factor receptor somatic aberrations in multiple primary lung cancers.

PURPOSE: For treatment decision and prognostic applications, we evaluated p53/epidermal growth factor receptor (EGFR) somatic aberrations in multiple primary lung cancers to differentiate multifocal tumors from intrapulmonary metastasis. EXPERIMENTAL DESIGN: Fifty-eight multiple primary lung cancers of 1,037 patients in a 10-year period were identified to investigate somatic mutations and altered expression of p53 and EGFR for clonality assessment. Genomic DNA was extracted from microdissected cells of paraffin-embedded multiple primary lung cancer tissues. Overexpression and somatic mutations in exons of p53 (exons 5-8) and tyrosine kinase domain of EGFR (exons 18-22) were examined by immunohistochemical staining and DNA sequencing, respectively. RESULTS: High frequency of somatic mutations in p53 (33 of 58, 56.9%) and/or EGFR (44 of 58, 75.9%) resulted in high discrimination rate of tumor clonality (50 of 58, 86.2%) of multiple primary lung cancers. Twenty-two cases (37.9%) were assessed as having the same clonality and 28 cases (48.3%) were determined as having different clonality, which further supported the carcinogenic theory of field cancerization. Notably, the occurrence of lymph node metastasis was more commonly observed in tumors with the same clonality (P = 0.045) and was associated with poor patient 5-year survival rate (P = 0.001). However, no correlation was found between tumor clonality and patient survival (P = 0.630). The EGFR somatic aberrations in 58 multiple primary lung cancers, including vascular invasion associated with EGFR overexpression (P = 0.012) and mutation (P = 0.025), further suggested the potential benefits of target therapy of inoperable multiple primary lung cancers. CONCLUSIONS: Our results suggest that analysis of somatic alterations in p53 and EGFR can significantly improve the clonality assessment and impact management of multiple primary lung cancer patients.

DNA Mutational Analysis↗

Prognostic factors for pulmonary metastasectomy in hepatocellular carcinoma.

PURPOSE: To identify the prognostic factors for pulmonary metastasectomy (PM-ectomy) in hepatocellular carcinoma (HCC). PATIENTS AND METHODS: We conducted a retrospective review of patients with pulmonary metastases (PM) from HCC who had undergone curative PM-ectomy at National Taiwan University Hospital between 1990 and 2004. Univariate (log-rank) and multivariate (Cox's model) analyses of survival were used to identify the significant prognostic factors. RESULTS: In total, 34 patients were eligible for curative PM-ectomy. The overall survival rates (Kaplan-Meier) after PM-ectomy were 65.2% and 27.5% at 2 and 5 years, respectively. High alpha-fetoprotein level, positive hepatic resection margin, and short disease-free interval (DFI) were unfavorable factors for overall survival from univariate analysis, however, only DFI (P = 0.028) was identified as an independently prognostic factor by multivariate analysis. Bilateral distribution and more PMs were unfavorable factors for PM-free survival from univariate analysis, with only PM number identified as an independent prognostic factor by multivariate analysis (P = 0.017). CONCLUSION: Patients with longer DFIs and fewer PMs can benefit from PM-ectomy in HCC.

Adult↗

Excellent survival of pediatric dermatofibrosarcoma protuberans in Taiwanese.

The purpose of this study was to explore the clinical outcome of pediatric dermatofibrosarcoma protuberans (DFSP) in Taiwan. Patients with DFSP diagnosed before 18 years and treated in our institute from 1977 to 2002 were identified through institutional cancer registry. After approved by institutional research ethic committee, active patient contact and linkage with National Residency Registry were done to explore their clinical outcome (Clinical Trials gov Identifier: NCT00173355). Twelve patients were identified. Pathological review confirmed DFSP for all of them. All of them underwent wide excision and none of them underwent neoadjuvant or adjuvant therapy. Nine patients underwent operation as initial therapy and three of them underwent salvage therapy. We recognized only one uncontrollable local recurrence and subsequent death. The 10-year and 15-year overall survival rates were 100 and 83%, respectively, without obvious complications. The prognosis of pediatric DFSP in Taiwanese was excellent.

Adolescent↗

Epidermal growth factor receptor mutations in needle biopsy/aspiration samples predict response to gefitinib therapy and survival of patients with advanced nonsmall cell lung cancer.

Recently, mutations in the epidermal growth factor receptor (EGFR) gene in nonsmall cell lung cancer (NSCLC) patients were reported to correlate with gefitinib response. Less than 30% of NSCLC patients are surgically resectable; however, molecular analysis has to rely on nonsurgical diagnostic tissue samples. The objective of this study is to investigate EGFR mutation analysis on needle biopsy/aspiration samples and its correlations with gefitinib response and patients' survival. EGFR mutation was assessed from DNA of 63 paraffin-embedded small needle biopsy/aspiration specimens from 62 patients with NSCLC treated with gefitinib. The peripheral blood lymphocyte DNA of the patients was sequenced to verify the EGFR mutation. EGFR mutations were found in 47% of 62 patients (60% of 20 CT-guided biopsies, 44% of 18 ultrasound-guided biopsies, 31% of 16 endoscopic biopsies and 44% of 9 effusion cell blocks). EGFR mutations were frequently present in females (p = 0.006) and never smokers (p = 0.04). Patients with EGFR mutations had a significantly better response rate compared to that of the nonmutation group (p < 0.001). Multivariate analysis showed that EGFR mutation (p < 0.001) and PS 0-1 (p = 0.02) were independently associated with a better response rate. Cox regression analysis showed that EGFR mutation was the independent prognostic factor for progression-free survival (p = 0.008) and overall survival (p = 0.03). In conclusion, EGFR mutation analysis is feasible in needle biopsy/aspiration paraffin-fixed specimens. EGFR mutation is an independent predictor of gefitinib response and survival in patients of advanced NSCLC treated by gefitinib.

Aged↗

Desmoid tumor of the head and neck.

BACKGROUND: [corrected] Desmoid tumors are rare benign tumors but have a tendency toward local recurrence after resection because of their infiltrative growth and frequent entrapment of vital structures in the head and neck region. We report 24 desmoid tumors of the head and neck and propose a reasonable approach in the management of such cases. METHODS: Twenty-four patients (9 male and 15 female; median age, 33 years; range, 0-66 years) with a desmoid tumor of the head and neck (neck, 15 patients; head, 9 patients) treated from 1990 to 2004 were retrospectively analyzed. The size ranged from 0.5 to 13 cm in diameter (mean, 3.6 cm). In the neck, 8 tumors were around the superficial layer of deep cervical fascia, whereas 4 tumors of the neck involved the prevertebral fascia and 2 involved brachial plexus. RESULTS: Twenty patients received complete resection of the tumor, but the section margin was positive in 8 patients, of which 6 patients remained free of disease in a period of 13 to 105 months. Three patients, including 2 with positive section margin and 1 with negative margin, developed recurrences, which were successfully removed again. Two patients underwent partial resection of the tumor because of brachial plexus involvement. One of them achieved regression after postoperative radiotherapy and the other had spontaneous regression. The hypopharygneal tumor in a newborn had spontaneously complete regression, and tracheostomy was closed at the age of 6 years. One patient remained with stable disease for 14 months after biopsy of the tumor without excision. CONCLUSION: The overall prognosis is still good despite frequent incomplete resection. Surgical resection of the tumor with close observation is suggested even if the section margin is positive. If a desmoid tumor cannot be removed grossly, regression or arrested growth of the remaining tumor is expected. Radiotherapy might be reserved for a growing tumor.

Adolescent↗

Photodynamic therapy with topical 5-aminolevulinic acid as a post-operative adjuvant therapy for an incompletely resected primary nasopharyngeal papillary adenocarcinoma: a case report.

BACKGROUND AND OBJECTIVES: Surgical excision of primary nasopharyngeal papillary adenocarcinoma is sometimes incomplete with remaining microscopic disease. Post-operative radiotherapy only has limited efficacy but may cause many complications. STUDY DESIGN/MATERIALS AND METHODS: Photodynamic therapy (PDT) was used as a post-operative adjuvant therapy for an incompletely resected primary nasopharyngeal papillary adenocarcinoma. A special form of 20% topical 5-aminolevulinic acid (5-ALA), which was originally a liquid form and became a gel form after applied on the nasopharynx, was used as the photosensitizer. A 2-mm optic fiber delivered the light (633 nm wavelength) to the lesion with a fluence rate of 100 mW/cm2 generated by a diode laser under 5 mm 0 degrees endoscope assistance. The total energy delivered was 150 joules/cm2. RESULTS: No significant acute side effect was noted and the nasopharyngeal wound healed rapidly. The patient is alive without locoregional recurrence or distant metastasis for 5 years. Articulation, salivation, and swallowing functions are all well preserved. CONCLUSION: Post-operative adjuvant PDT can successfully cure an otherwise difficult to treat disease with preservation of good life quality of the patient. Potential complications of PDT (e.g., photosensitivity) can be prevented by a special formulation of topical 5-ALA preparation.

Adenocarcinoma, Papillary↗

Treatment of mediastinal immature teratoma in a child with precocious puberty and Klinefelter's syndrome.

Teratoma is the most common germ cell tumor, which can be divided into the mature and the immature histologically. Concurrent Klinefelter's syndrome may be overlooked in a patient with a germ cell tumor. This is because the tumor that secrets alpha-fetoprotein and beta human chorionic gonadotropin can mimic puberty in a patient with Klinefelter's syndrome, masking the usual clinical signs. In reviewing the literature on the subject, the role of neoadjuvant and adjuvant chemotherapy remains ill-defined for the immature teratoma. Age-dependent prognosis seems to demonstrate that children with immature teratomas have a better outcome. We share the experience of treating a child with immature teratoma with surgical excision alone, and it ended in a local recurrence.

Antineoplastic Combined Chemotherapy Protocols↗

Video-assisted thoracoscopic excision of intradiaphragmatic bronchogenic cysts: two cases.

We report two cases of bronchogenic cyst in the diaphragm. Case 1 was a female patient with hepatocellular carcinoma. Computed tomography showed a tumor in the right lower lung and metastasis was suspected initially because of underlying disease and imaging findings. Case 2 was a female patient who presented with prolonged intermittent cough. Computed tomography showed a tumor in the left lower lung. Both tumors were excised by video-assisted thoracoscopic surgery, and the diagnosis was confirmed by histopathology.

Aged↗

Transcription repressor slug promotes carcinoma invasion and predicts outcome of patients with lung adenocarcinoma.

PURPOSE: In a previous genome-wide gene expression profiling analysis using an invasion cancer cell lines model, we have identified Slug as selectively overexpressed in the highly invasive cancer cells. Here, we investigated the clinical significance of Slug in lung adenocarcinoma and the role of Slug in the process of cancer cell invasion and metastasis. EXPERIMENTAL DESIGN: Real-time quantitative reverse transcription-PCR was used to investigate Slug mRNA in surgically resected lung adenocarcinoma of 54 patients and its correlation with survival. We overexpressed Slug in a lung adenocarcinoma cell line with very low Slug levels and investigated the in vitro and in vivo effects of Slug expression. RESULTS: High expression of Slug mRNA in lung cancer tissue was significantly associated with postoperative relapse (P = 0.03) and shorter patient survival (P < 0.001). The overexpression of Slug enhanced xenograft tumor growth and increased microvessel counts in angiogenesis assay. Both inducible and constitutive overexpression of Slug suppressed the expression of E-cadherin and increased the in vitro invasive ability. Zymography revealed increased matrix metalloproteinase-2 activity in Slug overexpressed cells. ELISA, reverse transcription-PCR, and immunohistochemistry confirmed the increase of matrix metalloproteinase-2 proteins and mRNA in Slug overexpressed cells and xenograft tumors. CONCLUSIONS: Slug expression can predict the clinical outcome of lung adenocarcinoma patients. Slug is a novel invasion-promoting gene in lung adenocarcinoma.

Adenocarcinoma↗

An esophageal mass with coexistent Mycobacterium chelonae and Candida albicans infections in an immunocompetent adult.

Mycobacteria chelonae was originally included in group IV of Runyon's classification of atypical mycobacteria. This rapidly growing environmental organism often caused infections in immunocompromised hosts. Candida albicans is a ubiquitous micro-organism and frequently isolated from the gastrointestinal tract. These two micro-organisms seldom cause esophageal diseases in healthy humans. We report a case of a fruit farmer with a submucosa tumor of distal esophagus caused by coexistence of M. chelonae and C. albicans infections, which was successfully treated by surgical resection and following antimicrobial regimens postoperatively.

Adult↗

Expression of the estrogen receptor beta in 37 surgically treated pulmonary sclerosing hemangiomas in comparison with non-small cell lung carcinomas.

Sclerosing hemangioma (SH) of the lung is an uncommon tumor with a predilection for middle-aged women. This special phenomenon prompted us to examine SH for the expression of ERalpha (human estrogen receptor) and ERbeta (a second isoform of estrogen receptor). To investigate the staining pattern of these tumors, we also stained lung tissues from patients with non-small cell lung carcinomas and nonneoplastic type II pneumocytes for comparison. Thirty-seven pulmonary SHs and 301 non-small cell lung cancers specimens were explored. Expression of ERalpha and ERbeta was immunohistochemically measured. The overall frequency of overexpression for ERbeta was 91.9%. It was detected in both female (in 91.4% of 35 cases) and male (in 100.0% of 2 tumors from men) patients. There was ERbeta overexpression in all 9 tumors of solid pattern, 6 of 7 tumors of papillary pattern, all 4 tumors of sclerotic pattern, 12 of 13 tumors of hemorrhagic pattern, and 3 of 4 tumors of mixed pattern. The staining pattern of the neoplastic cells of the SH was similar to that of type II pneumocytes adjacent to the tumor rather than that of non-small cell lung cancers, in which the frequency of ERbeta overexpression was 45.8%. However, there was no ERalpha detectable in these neoplasms. Estrogen receptor beta overexpression is very frequent in pulmonary SHs, which is similar to that of alveolar cells but quite different from non-small cell carcinoma.

Adult↗

Surgical lung biopsy for diffuse pulmonary disease: experience of 196 patients.

OBJECTIVE: Surgical lung biopsy is considered the final method of diagnostic modality in patients with undiagnosed diffuse pulmonary disease. Nevertheless, the effect of surgical lung biopsy on the diagnosis, treatment, and outcome of the patient still remains controversial. This study reviewed the experiences of surgical lung biopsies in 196 consecutive patients during the past 7 years. METHODS: Surgical lung biopsy was performed after achievement of general anesthesia through video-assisted thoracoscopic surgery or a 7-cm minithoracotomy. Biopsy specimens were swabbed for aerobic and anaerobic bacterial, fungal, and mycobacterial cultures. The sections of specimens were routinely stained with hematoxylin and eosin, and acid-fast, Gomori methenamine silver, Gram stain, or other special stains were added if necessary. RESULTS: The pathologic diagnosis after surgical lung biopsy included infection (30.6%), interstitial pneumonia or fibrosis (21.9%), diffuse alveolar damage (17.3%), neoplasm (13.3%), autoimmune diseases (8.2%), and others (8.2%). After surgical lung biopsy, 165 (84.2%) patients had changes in their therapy, 124 (63.3%) patients had clinical improvement of their conditions, and 119 (60.7%) patients survived to hospital discharge. Comparison between immunocompromised and immunocompetent patients showed that diagnosis of infection was significantly higher ( P < .01) in the former group (41.2% vs 20.2%). In addition, there was no significant difference in the distribution of diagnosis and rate of change in therapy between the respiratory failure and nonrespiratory failure groups. However, the rates of response to therapy and patient survival were significantly lower in the respiratory failure group (51.2% and 41.5%) than in the nonrespiratory failure group (71.9% and 78.1%, P < .05). There was no surgical mortality directly related to the procedure. The surgical morbidity rate was 6.6%. CONCLUSION: Surgical lung biopsy is a safe and accurate diagnostic tool for diffuse pulmonary disease. For a large proportion of the patients, change of therapy and then clinical improvement can be achieved after surgical lung biopsy. Surgical lung biopsy should be considered earlier in patients with undiagnosed diffuse pulmonary disease, especially when the respiratory condition is deteriorating.

Adolescent↗

The morphology of diaphragmatic defects in hepatic hydrothorax: thoracoscopic finding.

BACKGROUND: Until now, the pathophysiology of hepatic hydrothorax has been moot. We discuss (on the basis of gross videothoracoscopy findings in 11 cases and the literature) the pathogenesis and clinical presentation of this complex condition. METHODS: We prospectively studied 11 patients (age, 31-73 years; 6 men and 5 women) with refractory hepatic hydrothorax (Child-Pugh class B-C) who underwent thoracoscopic repair of diaphragmatic defects. The diaphragmatic defects were examined intraoperatively. RESULTS: The diaphragmatic defects stemming from hepatic hydrothorax were classified into 4 morphologic types: type I, no obvious defect (1 patient); type II, blebs lying on the diaphragm (4 patients); type III, broken defects (fenestrations) in the diaphragm (8 patients); and type IV, multiple gaps in the diaphragm (1 patient). The type of diaphragmatic defect did not correlate with the volume occupied by the pleural effusion in the preoperative chest radiograms. CONCLUSIONS: The finding of this study allowed hepatic hydrothorax pathophysiology to be directly visualized, and further studies concerning the treatment of hepatic hydrothorax might be based on these mechanisms.

Aged↗